CN105009656A - Method and device for clock synchronization - Google Patents

Abstract

Provided are a method and device for clock synchronization. The method comprises: a second base station receives a clock synchronization state of at least a first base station, the second base station determines a synchronization source base station on the basis of the clock synchronization state of the first base station; and, the second base station synchronizes on the basis of clock information of the synchronization source base station, where the clock synchronization state comprises whether or not clock synchronization is reliable and/or a clock synchronization type, and the clock synchronization type of the first base station comprises at least one among a clock synchronization source of the first base station, an operator to which the first base station belongs, a base station type of the first base station, and an identity of the first base station. The provided method and device for clock synchronization are capable of ensuring the accuracy of clock synchronization.

Description

Clock synchronization method and device

technical field

The present invention relates to communication technologies, and in particular to a clock synchronization method and device. Background technique

In a communication system, in order to ensure normal data transmission between the macro base station and each micro base station, and between each micro base station, clock synchronization needs to be implemented between each micro base station and between the micro base station and the macro base station. Clock synchronization includes time synchronization and/or frequency synchronization. When frequency synchronization is achieved between micro base stations and between micro base stations and macro base stations, it means that the frequency error of each micro base station or macro base station is within the set threshold range; when micro base stations and between micro base stations and macro base stations Realizing time synchronization between each micro base station refers to the deviation between the transmission timings of each micro base station, or the deviation between the transmission timings of each micro base station and the receiving timing of the same user equipment end, or the difference between the transmission timings of each micro base station and the macro base station or, the deviations between the sending timings of the micro base stations and the receiving timings of the macro base station reaching the same user equipment end are within the set threshold range. In the prior art, clock synchronization is implemented through network listening, that is, some micro base stations obtain clock synchronization through a clock synchronization signal provided by an external synchronization source, and provide clock synchronization for other micro base stations as a synchronization source. The clock synchronization signal enables other micro base stations to also realize clock synchronization, that is, inter-station synchronization. Wherein, the external synchronization source may be: a Global Navigation Satellite System (Global Navigation Satellite System, GNSS) such as a Global Positioning System (Global Positioning System, GPS for short), a wired network clock, a macro base station with a coverage overlapping area with a micro base station, etc. .

1 is a schematic structural diagram of a multi-hop synchronization system. In order to identify the synchronization state of each micro base station, the synchronization level of each micro base station is predetermined. The multi-hop synchronization scenario is especially common in densely deployed micro base stations. It can be seen from FIG. 1 that the macro base station obtains timing synchronization information through the Global Positioning System (Global Positioning System, GPS for short), that is, sets the synchronization level to 0; the micro base station 1 obtains the timing synchronization information through the macro base station, namely The synchronization level is set to 1; the micro base station 2 obtains timing synchronization information through the micro base station 1, that is, the synchronization level is set to 2; FIG. 1 shows a 3-hop synchronization system. The micro base station M in FIG. 1 is a base station deployed in isolation. When the micro base station M-1 obtains synchronization information through the micro base station M deployed in isolation, it is easy to lead to Inaccurate synchronization.

Usually, the base station that needs to be synchronized determines the synchronization source base station according to the received signal strength of other base stations and/or the synchronization level of other base stations. For example, the synchronization base station may determine the signal sending base station corresponding to the strongest received signal as the synchronization source base station.

However, in this synchronization method in the prior art, since some base stations are deployed in isolation, there is no need to consider the relationship with other base stations. Therefore, the clock synchronization of such base stations belongs to free configuration, and the timing reference point is random. larger. If the synchronization base station determines this type of base station as the synchronization source base station, the synchronization will be inaccurate. What's more serious is that in a multi-hop synchronization system, if the base station with inaccurate synchronization will serve as the synchronization source base station of other base stations, the clock synchronization error will propagate infinitely, thus causing the clock synchronization error to be impossible. control. Contents of the invention

Embodiments of the present invention provide a clock synchronization method and device to ensure the accuracy of clock synchronization. In a first aspect, an embodiment of the present invention provides a clock synchronization device, including: a receiving module, configured to receive a clock synchronization state of at least one first base station;

a determining module, configured to determine a synchronization source base station according to the clock synchronization state of the first base station; a synchronization module, configured to perform synchronization according to clock information of the synchronization source base station;

Wherein, the clock synchronization state includes whether the clock synchronization is reliable and/or the clock synchronization type, and the clock synchronization type of the first base station includes the clock synchronization source of the first base station, the operator to which the first base station belongs, At least one of the base station type of the first base station and the identity of the first base station.

In a first possible implementation manner of the first aspect, the receiving module is specifically configured to: receive the clock synchronization state of the first base station by means of air interface signaling.

In a second possible implementation manner of the first aspect, the receiving module is specifically configured to: receive the clock synchronization state of the first base station through a backhaul link; or, receive the clock synchronization state of the first base station through a centralized controller. A clock synchronization state of the first base station, where the clock synchronization state of the first base station is reported to the centralized controller by the first base station; or,

The clock synchronization state of the first base station is received by the macro base station, and the clock synchronization state of the first base station is reported to the macro base station by the first base station.

According to the first aspect, the first or the second possible implementation manner of the first aspect, in a third possible implementation manner, the receiving module is specifically configured to: receiving a cell identity of at least one first base station;

Judging the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule.

According to the first possible implementation manner of the first aspect, in a fourth possible implementation manner, the receiving module is specifically configured to:

receiving the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS sent by the first base station;

According to the master synchronization sequence? 88 and/or the secondary synchronization sequence SSS and the sixth preset rule to determine the cell identity of the first base station.

According to the first possible implementation manner of the first aspect, in a fifth possible implementation manner, the receiving module is specifically configured to:

receiving the sequence sent by the first base station, and judging the clock synchronization state of the first base station according to the sequence and a second preset rule.

According to the fifth possible implementation manner of the first aspect, in the sixth possible implementation manner, the receiving module is specifically configured to:

The second base station receives the primary synchronization sequence sent by the first base station? 88 and\or secondary synchronization sequence

SSS, and at least one sequence, there is a preset time interval between the sending time position of the sequence and the PSS or the SSS sending time position, and/or the sending frequency position of the sequence is the same as the PSS or the SSS There is a preset frequency interval between the SSS sending frequency positions.

According to the sixth or seventh possible implementation manner of the first aspect, in the seventh possible implementation manner, the receiving module is specifically configured to:

Judging the clock synchronization state of the first base station according to the format of the sequence and a third preset rule.

According to the first possible implementation manner of the first aspect, in an eighth possible implementation manner, the receiving module is specifically configured to:

Read the preset bits in the physical broadcast channel PBCH sent by the first base station;

Judging the clock synchronization state of the first base station according to preset bits in the PBCH and a fourth preset rule.

According to the first possible implementation manner of the first aspect, in a ninth possible implementation manner, the receiving module is specifically configured to:

reading the synchronization level sent by the first base station in the physical layer channel; Judging the clock synchronization state of the first base station according to the synchronization level and a fifth preset rule. According to the first possible implementation manner of the first aspect, in a tenth possible implementation manner, the receiving module is specifically configured to:

The clock synchronization state of the first base station sent by the UE is received through an uplink transmission channel, and the clock source synchronization state of the first base station is sent to the UE by the first base station through a physical layer channel.

According to the ninth or tenth possible implementation manner of the first aspect, in an eleventh possible implementation manner, the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, a bearer system The channel of the information block SIB, the paging channel, the physical downlink control channel PDCCH, the enhanced physical downlink control channel EPDCCH, and the physical downlink shared channel PDSCH.

In a second aspect, an embodiment of the present invention provides a clock synchronization device, including:

A determination module, configured to determine its own clock synchronization status, where the clock synchronization status of the first base station includes whether the clock synchronization of the first base station is reliable and/or the type of clock synchronization, where the clock synchronization status of the first base station The synchronization type includes at least one of the clock synchronization source of the first base station, the operator to which the first base station belongs, the base station type of the first base station, and the identity of the first base station;

A sending module, configured to send the clock synchronization state of the first base station to a second base station, so that the second base station determines a synchronization source base station according to the clock synchronization state of the first base station, and according to the first base station The clock information is synchronized.

In a first possible implementation manner of the second aspect, the sending module is specifically configured to: send the clock synchronization state of the first base station in an air interface signaling manner.

In a second possible implementation manner of the second aspect, the sending module is specifically configured to: send the clock synchronization status of the first base station through a backhaul link; or, send the clock synchronization status of the first base station to reporting the synchronization state to the centralized controller, so that the centralized controller sends the clock synchronization state of the first base station to the second base station; or,

reporting the clock synchronization state of the first base station to the macro base station, so that the macro base station sends the clock synchronization state of the first base station to the second base station.

According to the second aspect, the first or the second possible implementation manner of the second aspect, in a third possible implementation manner, the sending module is specifically configured to:

sending the cell identity of the first base station to the second base station, so that the second base station judges the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule state.

According to the first possible implementation manner of the second aspect, in a fourth possible implementation manner, the sending module is specifically configured to:

Determine the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS according to its own clock synchronization state and the sixth preset rule;

sending the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS to the second base station, so that the second base station determines the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS The cell identifier of the first base station.

According to the first possible implementation manner of the second aspect, in a fifth possible implementation manner, the sending module is specifically configured to:

Determine at least one sequence according to its own clock synchronization state and a second preset rule;

The sequence is sent by way of air interface signaling, so that the second base station judges the clock synchronization state of the first base station according to the sequence and the second preset rule.

According to the fifth possible implementation of the second aspect, in the sixth possible implementation, there is a preset time interval between the sending time position of the sequence and the sending time position of the PSS or the SSS , and\or there is a preset frequency interval between the sending frequency position of the sequence and the sending frequency position of the PSS or the SSS;

The sending module is specifically used for:

Sending the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS, and at least one sequence to the second base station.

According to the sixth or seventh possible implementation manner of the second aspect, in the seventh possible implementation manner, the sending module is specifically configured to:

determining the format of the sequence according to its own clock synchronization state and a third preset rule; sending the sequence to the second base station according to the format, so that the second base station judges the sequence according to the format of the sequence Describe the clock synchronization state of the first base station.

According to the first possible implementation manner of the second aspect, in an eighth possible implementation manner, the sending module is specifically configured to:

Carrying the clock synchronization state of itself in the preset bit in the physical broadcast channel PBCH; sending the physical broadcast channel PBCH to the second base station, so that the second base station according to the preset bit in the physical broadcast channel PBCH Set the bit and the fourth preset rule to judge the time of the first base station Clock synchronization status.

According to the first possible implementation manner of the second aspect, in a ninth possible implementation manner, the sending module is specifically configured to:

Determine the synchronization level of the first base station according to its own clock synchronization state and a fifth preset rule;

sending the synchronization level of the first base station to the second base station on a physical layer channel, so that the second base station judges the clock of the first base station according to the synchronization level and the fifth preset rule sync state.

According to the first possible implementation manner of the second aspect, in a tenth possible implementation manner, the sending module is specifically configured to:

Sending the clock synchronization state of the first base station to the UE through a physical layer channel, so that the UE sends the clock synchronization state of the first base station to the second base station through an uplink transmission channel.

According to the ninth or tenth possible implementation manner of the second aspect, in an eleventh possible implementation manner, the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, a bearer system The channel of the information block SIB, the paging channel, the physical downlink control channel PDCCH, the enhanced physical downlink control channel EPDCCH, and the physical downlink shared channel PDSCH.

In a third aspect, an embodiment of the present invention provides a base station, including:

a receiver, configured to receive a clock synchronization state of at least one first base station,

a processor, configured to determine a synchronization source base station according to the clock synchronization state of the first base station; the processor is also configured to perform synchronization according to clock information of the synchronization source base station;

Wherein, the clock synchronization state includes whether the clock synchronization is reliable and/or the clock synchronization type, and the clock synchronization type of the first base station includes the clock synchronization source of the first base station, the operator to which the first base station belongs, At least one of the base station type of the first base station and the identity of the first base station.

In a first possible implementation manner of the third aspect, the receiver is specifically configured to: receive the clock synchronization state of the first base station in an air interface signaling manner.

In a second possible implementation manner of the third aspect, the receiver is specifically configured to: receive the clock synchronization status of the first base station through a backhaul link; or, receive the first base station clock synchronization status through a centralized controller. A clock synchronization state of a base station, the clock synchronization state of the first base station is reported to the centralized controller by the first base station; or,

The macro base station receives the clock synchronization state of the first base station, and the clock synchronization state of the first base station The step state is reported by the first base station to the macro base station.

According to the third aspect, the first or the second possible implementation manner of the third aspect, in the third possible implementation manner, the receiver is specifically used for:

receiving a cell identity of at least one first base station;

Judging the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule.

According to the first possible implementation manner of the third aspect, in a fourth possible implementation manner, the receiver is specifically configured to:

receiving the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS sent by the first base station;

According to the master synchronization sequence? 88 and/or the secondary synchronization sequence SSS and the sixth preset rule to determine the cell identity of the first base station.

According to the first possible implementation manner of the third aspect, in a fifth possible implementation manner, the receiver is specifically configured to:

receiving the sequence sent by the first base station, and judging the clock synchronization state of the first base station according to the sequence and a second preset rule.

According to a fifth possible implementation manner of the third aspect, in a sixth possible implementation manner, the receiver is specifically configured to:

receiving the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS, and at least one sequence sent by the first base station, and there is a preset interval between the sending time position of the sequence and the PSS or the SSS sending time position and/or there is a preset frequency interval between the sending frequency position of the sequence and the sending frequency position of the PSS or the SSS.

According to the sixth or seventh possible implementation manner of the third aspect, in the seventh possible implementation manner, the receiver is specifically configured to:

Judging the clock synchronization state of the first base station according to the format of the sequence and a third preset rule.

According to the first possible implementation manner of the third aspect, in an eighth possible implementation manner, the receiver is specifically configured to:

Read the preset bits in the physical broadcast channel PBCH sent by the first base station;

Judging the clock synchronization state of the first base station according to preset bits in the PBCH and a fourth preset rule. According to the first possible implementation manner of the third aspect, in a ninth possible implementation manner, the receiver is specifically configured to:

reading the synchronization level sent by the first base station in the physical layer channel;

Judging the clock synchronization state of the first base station according to the synchronization level and a fifth preset rule. According to the first possible implementation manner of the third aspect, in a tenth possible implementation manner, the receiver is specifically configured to:

The clock synchronization state of the first base station sent by the UE is received through an uplink transmission channel, and the clock source synchronization state of the first base station is sent to the UE by the first base station through a physical layer channel.

According to the ninth or tenth possible implementation manner of the third aspect, in an eleventh possible implementation manner, the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, a bearer system The channel of the information block SIB, the paging channel, the physical downlink control channel PDCCH, the enhanced physical downlink control channel EPDCCH, and the physical downlink shared channel PDSCH.

In a fourth aspect, an embodiment of the present invention provides a clock synchronization base station, including:

A processor, configured to determine its own clock synchronization state, where the clock synchronization state of the first base station includes whether the clock synchronization of the first base station is reliable and/or the type of clock synchronization, where the clock synchronization state of the first base station The synchronization type includes at least one of the clock synchronization source of the first base station, the operator to which the first base station belongs, the base station type of the first base station, and the identity of the first base station;

A transmitter, configured to send the clock synchronization state of the first base station to a second base station, so that the second base station determines a synchronization source base station according to the clock synchronization state of the first base station, and according to the first base station The clock information is synchronized.

In a first possible implementation manner of the fourth aspect, the transmitter is specifically configured to: transmit the clock synchronization state of the first base station in an air interface signaling manner.

In a second possible implementation manner of the fourth aspect, the transmitter is specifically configured to: transmit the clock synchronization status of the first base station through a backhaul link; or, transmit the clock synchronization status of the first base station to reporting the synchronization state to the centralized controller, so that the centralized controller sends the clock synchronization state of the first base station to the second base station; or,

reporting the clock synchronization state of the first base station to the macro base station, so that the macro base station sends the clock synchronization state of the first base station to the second base station.

According to the fourth aspect, the first or second possible implementation of the fourth aspect, in the third In a possible implementation manner, the transmitter is specifically used for:

sending the cell identity of the first base station to the second base station, so that the second base station judges the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule.

According to the first possible implementation manner of the fourth aspect, in a fourth possible implementation manner, the transmitter is specifically configured to:

Determine the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS according to its own clock synchronization state and the sixth preset rule;

Sending the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS to the second base station, so that the second base station uses the primary synchronization sequence? 88 and/or the secondary synchronization sequence SSS to determine the cell identity of the first base station.

According to the first possible implementation manner of the fourth aspect, in a fifth possible implementation manner, the transmitter is specifically configured to:

Determine at least one sequence according to its own clock synchronization state and a second preset rule;

The sequence is sent by way of air interface signaling, so that the second base station judges the clock synchronization state of the first base station according to the sequence and the second preset rule.

According to the fifth possible implementation of the fourth aspect, in the sixth possible implementation, there is a preset time interval between the sending time position of the sequence and the sending time position of the PSS or the SSS , and\or there is a preset frequency interval between the sending frequency position of the sequence and the sending frequency position of the PSS or the SSS.'

The transmitter is specifically used for:

Sending the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS, and at least one sequence to the second base station.

According to the sixth or seventh possible implementation manner of the fourth aspect, in the seventh possible implementation manner, the transmitter is specifically configured to:

determining the format of the sequence according to its own clock synchronization state and a third preset rule; sending the sequence to the second base station according to the format, so that the second base station judges the sequence according to the format of the sequence Describe the clock synchronization state of the first base station.

According to the first possible implementation manner of the fourth aspect, in an eighth possible implementation manner, the transmitter is specifically configured to: Carrying the clock synchronization state of itself in the preset bit in the physical broadcast channel PBCH; sending the physical broadcast channel PBCH to the second base station, so that the second base station according to the preset bit in the physical broadcast channel PBCH Set the bit and the fourth preset rule to judge the clock synchronization state of the first base station.

According to the first possible implementation manner of the fourth aspect, in a ninth possible implementation manner, the transmitter is specifically configured to:

Determine the synchronization level of the first base station according to its own clock synchronization state and a fifth preset rule;

sending the synchronization level of the first base station to the second base station on a physical layer channel, so that the second base station judges the clock of the first base station according to the synchronization level and the fifth preset rule sync state.

According to the first possible implementation manner of the fourth aspect, in a tenth possible implementation manner, the transmitter is specifically configured to:

Sending the clock synchronization state of the first base station to the UE through a physical layer channel, so that the UE sends the clock synchronization state of the first base station to the second base station through an uplink transmission channel.

According to the ninth or tenth possible implementation manner of the fourth aspect, in an eleventh possible implementation manner, the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, a bearer system The channel of the information block SIB, the paging channel, the physical downlink control channel PDCCH, the enhanced physical downlink control channel EPDCCH, and the physical downlink shared channel PDSCH.

In a fifth aspect, an embodiment of the present invention provides a clock synchronization method, including:

the second base station receives at least one clock synchronization status of the first base station,

The second base station determines the synchronization source base station according to the clock synchronization state of the first base station;

The second base station performs synchronization according to the clock information of the synchronization source base station;

Wherein, the clock synchronization state includes whether the clock synchronization is reliable and/or the clock synchronization type, and the clock synchronization type of the first base station includes the clock synchronization source of the first base station, the operator to which the first base station belongs, At least one of the base station type of the first base station and the identity of the first base station.

In a first possible implementation manner of the fifth aspect, the second base station receiving at least one clock synchronization state of the first base station includes:

The second base station receives the clock synchronization state of the first base station through air interface signaling. In a second possible implementation manner of the fifth aspect, the second base station receives at least one first The clock synchronization status of a base station includes:

The second base station receives the clock synchronization state of the first base station through a backhaul link; or,

The second base station receives the clock synchronization state of the first base station through a centralized controller, and the clock synchronization state of the first base station is reported to the centralized controller by the first base station; or, the The second base station receives the clock synchronization state of the first base station through the macro base station, and the clock synchronization state of the first base station is reported to the macro base station by the first base station.

According to the fifth aspect, or the first or second possible implementation manner of the fifth aspect, in a third possible implementation manner, the second base station receiving the clock synchronization state of at least one first base station includes:

The second base station receives at least one cell identity of the first base station;

The second base station judges the clock synchronization status of the first base station according to the cell identity of the first base station and a first preset rule.

According to the first possible implementation manner of the fifth aspect, in a fourth possible implementation manner, the second base station receiving at least one cell identity of the first base station includes:

The second base station receives the primary synchronization sequence sent by the first base station? 88 and\or secondary synchronization sequence

SSS;

The second base station according to the primary synchronization sequence? 88 and/or the secondary synchronization sequence SSS and the sixth preset rule determine the cell identity of the first base station.

According to the first possible implementation manner of the fifth aspect, in a fifth possible implementation manner, receiving the clock synchronization state of the first base station by the second base station through air interface signaling includes: the The second base station receives the sequence sent by the first base station, and judges the clock synchronization state of the first base station according to the sequence and a second preset rule.

In a fifth possible implementation manner according to the fifth aspect, in a sixth possible implementation manner, reading the sequence sent by the first base station by the second base station includes:

The second base station receives the primary synchronization sequence sent by the first base station? 88 and/or a secondary synchronization sequence SSS, and at least one sequence, there is a preset time interval between the sending time position of the sequence and the sending time position of the PSS or the SSS, and/or the sending of the sequence There is a preset frequency interval between the frequency position and the PSS or the SSS sending frequency position.

According to the sixth or seventh possible implementation of the fifth aspect, in the seventh possible implementation In the manner, the second base station judges the clock synchronization state of the first base station according to the sequence and a second preset rule, including:

The second base station judges the clock synchronization state of the first base station according to the format of the sequence and a third preset rule.

According to the first possible implementation manner of the fifth aspect, in an eighth possible implementation manner, the receiving, by the second base station, the clock synchronization state of the first base station through air interface signaling includes: the The second base station reads preset bits in the physical broadcast channel PBCH sent by the first base station;

The second base station judges the clock synchronization state of the first base station according to preset bits in the PBCH and a fourth preset rule.

According to the first possible implementation manner of the fifth aspect, in a ninth possible implementation manner, the second base station receives the clock source synchronization status of the first base station through air interface signaling, including: the The second base station reads the synchronization level sent by the first base station in the physical layer channel; the second base station judges the clock synchronization state of the first base station according to the synchronization level and a fifth preset rule.

According to the first possible implementation manner of the fifth aspect, in a tenth possible implementation manner, receiving the clock synchronization state of the first base station by the second base station through air interface signaling includes: the first base station The second base station receives the clock synchronization state of the first base station sent by the UE through an uplink transmission channel, and the information about the clock synchronization state of the first base station is sent to the UE by the first base station through a physical layer channel .

According to the ninth or tenth possible implementation manner of the fifth aspect, in an eleventh possible implementation manner, the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, a bearer system The channel of the information block SIB, the paging channel, the physical downlink control channel PDCCH, the enhanced physical downlink control channel EPDCCH, and the physical downlink shared channel PDSCH.

In a sixth aspect, an embodiment of the present invention provides a clock synchronization method, including:

The first base station determines its own clock synchronization state, the clock synchronization state of the first base station includes whether the clock synchronization of the first base station is reliable and/or the type of clock synchronization, and the clock synchronization state of the first base station The type includes at least one of the clock synchronization source of the first base station, the operator to which the first base station belongs, the base station type of the first base station, and the identity of the first base station;

The first base station sends the clock synchronization state of the first base station to the second base station, so that the second The base station determines a synchronization source base station according to the clock synchronization state of the first base station, and performs synchronization according to the clock information of the first base station.

In a first possible implementation manner of the sixth aspect, the first base station sending the clock synchronization state of the first base station to the second base station includes:

The first base station sends the clock synchronization state of the first base station by way of air interface signaling. In a second possible implementation manner of the sixth aspect, the first base station sending the clock synchronization state of the first base station to the second base station includes:

The first base station sends the clock synchronization state of the first base station through a backhaul link; or,

The first base station reports the clock synchronization state of the first base station to a centralized controller, so that the centralized controller sends the clock synchronization state of the first base station to the second base station; or, The first base station reports the clock synchronization state of the first base station to the macro base station, so that the macro base station sends the clock synchronization state of the first base station to the second base station.

According to the sixth aspect, or the first or second possible implementation manner of the sixth aspect, in a third possible implementation manner, the first base station sends the clock synchronization information of the first base station to the second base station. status, including:

The first base station sends the cell identity of the first base station to the second base station, so that the second base station judges the cell identity of the first base station according to the cell identity of the first base station and a first preset rule Clock synchronization status.

According to the first possible implementation manner of the sixth aspect, in a fourth possible implementation manner, sending the cell identity of the first base station by the first base station to the second base station includes:

The first base station determines the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS according to its own clock synchronization state and a sixth preset rule;

The first base station sends the primary synchronization sequence to the second base station? 88 and/or the secondary synchronization sequence SSS, so that the second base station determines the cell identity of the first base station according to the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS.

According to the first possible implementation manner of the sixth aspect, in a fifth possible implementation manner, the first base station sending the clock synchronization status of the first base station through air interface signaling includes: the The first base station determines at least one sequence number according to its own clock synchronization state and a second preset rule. The first base station sends the sequence through air interface signaling, so that the second base station judges the clock synchronization state of the first base station according to the sequence and the second preset rule.

In the fifth possible implementation manner according to the sixth aspect, in the sixth possible implementation manner, there is a preset time interval between the sending time position of the sequence and the sending time position of the PSS or the SSS , and\or there is a preset frequency interval between the sending frequency position of the sequence and the sending frequency position of the PSS or the SSS;

The first base station sends the sequence through air interface signaling, including:

The first base station sends the primary synchronization sequence to the second base station? 88 and\or secondary synchronization sequence SSS, and at least one of said sequences.

According to the sixth or seventh possible implementation manner of the sixth aspect, in the seventh possible implementation manner, the first base station sends the clock synchronization status of the first base station through air interface signaling, include:

The first base station determines the format of the sequence according to its own clock synchronization state and a third preset rule;

The first base station sends the sequence to the second base station according to the format, so that the second base station judges the clock synchronization state of the first base station according to the format of the sequence.

According to the first possible implementation manner of the sixth aspect, in an eighth possible implementation manner, the first base station sending the clock synchronization status of the first base station through air interface signaling includes: first The base station carries its own clock synchronization state in the preset bits in the physical broadcast channel PBCH,

The first base station sends the physical broadcast channel PBCH to the second base station, so that the second base station judges the physical broadcast channel PBCH according to preset bits in the physical broadcast channel PBCH and a fourth preset rule Clock synchronization status.

According to the first possible implementation manner of the sixth aspect, in a ninth possible implementation manner, the first base station sending the clock synchronization state of the first base station through air interface signaling includes: the The first base station determines the synchronization level of the first base station according to its own clock synchronization state and a fifth preset rule;

The first base station sends the synchronization level of the first base station to the second base station on a physical layer channel, so that the second base station judges the synchronization level according to the synchronization level and the fifth preset rule. The clock synchronization state of the first base station. According to the first possible implementation manner of the sixth aspect, in a tenth possible implementation manner, the first base station sending the clock synchronization state of the first base station through air interface signaling includes: the The first base station sends the clock synchronization state of the first base station to the UE through a physical layer channel, so that the UE sends the clock synchronization state of the first base station to the second base station through an uplink transmission channel.

According to the ninth or tenth possible implementation manner of the sixth aspect, in an eleventh possible implementation manner, the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, a bearer system The channel of the information block SIB, the paging channel, the physical downlink control channel PDCCH, the enhanced physical downlink control channel EPDCCH, and the physical downlink shared channel PDSCH.

In the clock synchronization method and device provided in the embodiments of the present invention, after the first base station determines its own clock synchronization state, it sends the clock synchronization state to the second base station, and the second base station synchronizes the clock synchronization state according to the clock synchronization state of the first base station. The state determines the synchronization source base station, and then performs synchronization based on the synchronization source base station, that is, the second base station can first confirm the clock synchronization state of the first base station before performing synchronization, and only after determining the clock synchronization state of the first base station Reliable and/or the clock synchronization type of the first base station has a high priority before the first base station is determined as the synchronization source base station, thereby avoiding the synchronization of the second base station due to inaccurate clock information of the first base station For the problem of inaccuracy, ensuring that the second base station performs synchronization according to correct clock information can improve the accuracy of clock synchronization of the entire system. Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings according to these drawings without any creative effort.

Fig. 1 is a schematic structural diagram of a multi-hop synchronization system;

FIG. 2 is a schematic structural diagram of Embodiment 1 of the clock synchronization device of the present invention;

FIG. 3 is a schematic structural diagram of Embodiment 2 of the clock synchronization device of the present invention;

FIG. 4 is a schematic structural diagram of Embodiment 1 of the base station of the present invention;

FIG. 5 is a schematic structural diagram of Embodiment 2 of the base station of the present invention;

FIG. 6 is an interactive flowchart of Embodiment 1 of the clock synchronization method of the present invention; Fig. 7 is a schematic diagram of the time-frequency distribution of PSS and SSS in the FDD system. Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

In this paper, unless otherwise specified, the smaller the synchronization level, the higher the synchronization accuracy, or the smaller the number of synchronization hops experienced between the base station and the external synchronization source. The base stations described in the embodiments of the present invention include macro base stations and micro base stations. In each of the following embodiments, the first base station is used to indicate a base station that provides synchronization information, and the second base station is used to indicate a base station to be synchronized (synchronization information needs to be updated). base station. The second base station executes the synchronization source base station search process, which may be performed when the second base station is just powered on, or may be performed when the second base station searches for the synchronization source again after it has been running for a period of time after being powered on.

FIG. 2 is a schematic structural diagram of Embodiment 1 of the clock synchronization device of the present invention. The device of this embodiment can be set on a base station, and the base station can be used as a second base station, that is, a base station that needs to update synchronization information. As shown in FIG. 2, the device 200 of this embodiment may include: a receiving module 11, a determining module 12, and a synchronizing module 13, wherein,

The receiving module 11 may be configured to receive a clock synchronization state of at least one first base station; the determining module 12 may be configured to determine a synchronization source base station according to the clock synchronization state of the first base station;

The synchronization module 13 may be configured to perform synchronization according to the clock information of the synchronization source base station; wherein, the clock synchronization state includes whether the clock synchronization is reliable and/or the clock synchronization type, and the clock synchronization status of the first base station The clock synchronization type includes at least one of a clock synchronization source of the first base station, an operator to which the first base station belongs, a base station type of the first base station, and an identity of the first base station.

The clock synchronization source included in the above clock synchronization state can be, for example: Clock synchronization comes from Global Navigation Satellite System (Global Navigation Satellite System, GNSS for short), such as GPS, Beidou satellite navigation system, or a cable network (such as IEEE1588 clock synchronization synchronous protocol, Ethernet clock synchronization protocol), or the clock synchronization provided by the macro base station with the coverage overlapping area of the micro base station synchronization, or clock synchronization provided by the femtocell.

The base station type of the first base station may be: a macro base station, a micro base station, a micro base station is characterized by low transmission power and a small coverage area, and a micro base station may specifically include a metro cell (Metro cell), a micro cell (Micro cell), and a pico cell (Pico cell), Femto cell (Femto cell).

The identity of the first base station may be: a base station that directly implements clock synchronization through an external synchronization source (for example, a header), a base station that does not directly implement clock synchronization through an external synchronization source (for example, a non-header), and the external synchronization source may be Clock synchronization provided by GNSS; Clock synchronization provided by cable network; Clock synchronization provided by macro base station; The base station that does not directly realize clock synchronization through an external synchronization source can be: a base station that obtains clock synchronization through a header.

It should be noted that the identity of a base station is usually for a cluster of base stations, a cluster of base stations may be multiple base stations densely deployed within a certain geographical area, and the division of clusters may be defined by operators during deployment. The header in the base station may be a base station that obtains clock synchronization through an external clock synchronization source in the cluster base station, and the non-header is a base station that obtains clock synchronization through the header in the cluster base station.

Whether the clock synchronization is reliable can be defined as: a base station that can obtain clock information directly through an external synchronization source or indirectly through an external synchronization source is regarded as a base station with reliable clock synchronization, wherein the clock is obtained directly through an external synchronization source The information means that the base station can directly obtain clock information from GNSS, such as GPS, Beidou satellite navigation system, or wired network (such as IEEE1588 clock synchronization protocol, Ethernet clock synchronization protocol); indirectly obtain the clock through an external synchronization source The information refers to the clock information obtained by the base station from an external synchronization source through other base stations. For example, base station A directly obtains clock synchronization through an external synchronization source, and base station B obtains clock synchronization through base station A, then the clock synchronization of base station B belongs to Synchronization information obtained indirectly through an external synchronization source, SP, can also be considered reliable.

The definition of whether the clock synchronization is reliable can also be: the clock synchronization of the base station that takes into account the relative clock synchronization relationship with other base stations is considered reliable, and the clock synchronization of the base station that does not consider the relative clock synchronization relationship with other base stations Synchronization is considered unreliable.

The definition of whether clock synchronization is reliable can also be: the clock synchronization of synchronized base stations is considered reliable, and the clock synchronization of unsynchronized (or out-of-synchronization) base stations is considered unreliable.

The definition of whether the clock synchronization is reliable can also be: the clock synchronization of the base station directly or indirectly through the GNSS or wired network timing is considered reliable, and the clock synchronization of the base station not directly or indirectly passed through the GNSS or wired network timing is considered to be unsafe. Reliable, such as an isolated base station or any one of a cluster of isolated base stations. The definition of whether the clock synchronization is reliable can also be: clock synchronization of a base station whose clock source is GNSS, a cable network, and at least one synchronous base station is considered reliable; otherwise, it is considered unreliable, such as a base station deployed in isolation or Any base station in a cluster of base stations deployed in isolation.

Whether the clock synchronization is reliable can also be defined according to other rules. For example, it can also be defined as: as long as the base station meets any of the above-mentioned definitions of "unreliable clock synchronization", it is considered unreliable; or as long as it meets the above-mentioned Any base station defined by "reliable clock synchronization" is considered to be reliable. This embodiment of the present invention does not limit this.

It should be noted that the definition of whether the clock synchronization is reliable can be defined by a standard protocol specification, or can be implemented by network side configuration, for example, by OAM configuration, can also be implemented by macro base station configuration, or can be implemented by the base station side. Make the first base station and/or the second base station aware of each other.

The first base station may include a macro base station and a micro base station, and the second base station is preferably a micro base station, but may also include a macro base station. The first base station and the second base station may belong to the same operator, or may belong to different operators.

Optionally, in a manner, the receiving module 11 may specifically be used for:

Receive the clock synchronization state of the first base station by way of air interface signaling.

Optionally, in another manner, the receiving module 11 may specifically be used for:

Receiving the clock synchronization state of the first base station through a backhaul link; or receiving the clock synchronization state of the first base station through a centralized controller, where the clock synchronization state of the first base station is determined by the reported by the first base station to the centralized controller; or,

The clock synchronization state of the first base station is received by the macro base station, and the clock synchronization state of the first base station is reported to the macro base station by the first base station.

Wherein, the backhaul link backhaul may be an S1/X2 interface.

Specifically, when the clock synchronization state of the first base station indicates that the clock synchronization of the first base station is reliable and/or indicates that the clock synchronization type of the first base station has a high priority, the clock synchronization of this embodiment The synchronization device may use the first base station as a candidate synchronization source base station or directly determine the first base station as the synchronization source base station.

Since the receiving module 11 may receive the clock synchronization states of multiple first base stations, and there may be multiple first base stations with the same clock synchronization state, for example, there are multiple first base stations with reliable clock synchronization, and these reliable clock synchronization All the first base stations can be used as candidate synchronization source base stations, and the determination module 12 can select one of the first base stations as the synchronization source base station according to preset rules, for example, according to the synchronization level To select, select the first base station with the smallest synchronization level as the synchronization source base station; or, select according to the priority of the clock synchronization type, which can provide high synchronization accuracy, small synchronization error, and facilitate communication between different operators. The clock synchronization type of the first base station that is inter-synchronized has a high priority, and the priority of the clock synchronization type can be reflected as follows: the priority of the clock source being GNSS is greater than the priority of the clock source being wired network or wireless synchronization, clock The priority of the first base station whose source is GNSS or wired network is higher than that of the first base station whose clock source is wireless synchronization, and the clock source is the first base station of wireless synchronization, which means that the first base station receives the synchronization signal sent by other base stations Synchronization is achieved; the priority of the macro base station is higher than that of the micro base station, and the priority of the first base station belonging to the same operator as the second base station is higher than that of the first base station not belonging to the same operator as the second base station (in some scenarios It may also be set that the priority of the first base station belonging to the same operator as the second base station is lower than that of the first base station not belonging to the same operator as the second base station); or, if it is determined that the first base station is the synchronization source base station, the Other synchronized base stations have the least impact, then such a first base station may be considered to have a high-priority clock synchronization type, and the first base station may be used as a synchronization source base station. The least impact may refer to For the base stations that have been synchronized, the number of base stations that need to readjust the clock synchronization is the least; or, the clock synchronization type priority of the first base station as a header is greater than the clock synchronization type priority of the first base station as a non-header, as The header and/or the first base station as a non-header may be marked by the clock synchronization source of the first base station, or directly marked by whether the first base station is a header or a non-header.

For the case of multiple candidate synchronization source base stations, the second base station may also select according to other rules, which is not limited in this embodiment of the present invention.

It should be noted that the priorities corresponding to different clock synchronization types can be defined by standard protocol specifications, or can be implemented by network side configuration, for example, by OAM configuration, or by macro base station configuration, or by the base station side. The behavior is not limited here, so that the first base station and/or the second base station can know each other.

In the clock synchronization device of this embodiment, after the clock synchronization state of the first base station is received by the receiving module, the determination module determines the synchronization source base station according to the clock synchronization state of the first base station, and then the synchronization module then based on the synchronization The source base station performs synchronization, that is, it is possible to confirm the clock synchronization state of the first base station before performing synchronization, and only when it is determined that the clock synchronization of the first base station is reliable and/or the clock synchronization type of the first base station has a high priority The first base station is determined as the synchronization source base station only after the stage, so that the problem of inaccurate synchronization of the second base station caused by inaccurate clock information of the first base station can be avoided, and the second base station can be ensured to perform synchronization based on correct clock information. Synchronization, which can improve the clock synchronization of the entire system accuracy.

Further, the receiving module 11 can be configured in the following six ways.

In a first optional implementation manner, a cell identity (cell identity, cell ID for short) is used to indicate the clock synchronization state.

Therefore, the receiving module 11 can specifically be used for:

receiving a cell identity of at least one first base station;

Judging the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule.

In a second optional implementation manner, the clock synchronization state of the first base station may be indicated by a primary synchronization sequence PSS and/or a secondary synchronization sequence SSS.

The receiving module 11 can specifically be used for:

receiving the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS sent by the first base station;

According to the master synchronization sequence? 88 and/or the secondary synchronization sequence SSS and the sixth preset rule to determine the cell identity of the first base station.

It should be noted that the second optional implementation manner may include two situations:

One case is to use both the PSS and the SSS to indicate the clock synchronization state of the first base station. This case may correspond to the solution of determining the clock synchronization state according to the cell identifier in the first optional implementation manner, that is, in After receiving the PSS and SSS of the first base station, the receiving module 11 may determine the cell identity of the first base station according to the PSS and/or SSS, and then determine the clock synchronization of the first base station according to a first preset rule Synchronization state; Of course, PSS and SSS may also be used to directly indicate the clock synchronization state, that is, after the receiving module 11 receives the PSS and SSS of the first base station, it directly determines the clock synchronization state of the first base station according to the sixth preset rule .

Another situation is to use only one of PSS and SSS to indicate the clock synchronization state of the first base station, that is, the receiving module 11 receives the PSS and SSS of the first base station, but only determines the first base station according to the PSS or SSS clock synchronization status.

In a third optional implementation manner, one or more sequences may be introduced to indicate the clock synchronization state of the first base station. The sequence can be sent through air interface signaling.

Therefore, the receiving module 11 can specifically be used for:

receiving the sequence sent by the first base station, and judging the clock synchronization state of the first base station according to the sequence and a second preset rule. Wherein, there is a preset time interval between the transmission time position of the sequence and the PSS or the SSS transmission time position, and/or the transmission frequency position of the sequence and the PSS or the SSS transmission frequency position There is a preset frequency interval between them. Therefore, further specifically, the receiving module 11 may receive the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS, and at least one sequence sent by the first base station.

In the above-mentioned third optional implementation manner, the second base station may detect at a preset sending position and/or a preset frequency position to determine whether the sequence exists, or determine what sequence the received sequence is to determine the first sequence. Clock synchronization status of a base station.

Optionally, in addition to using the imported sequence to indicate the clock synchronization state of the first base station, a pattern (pattern) of the sequence may also be used to indicate the clock synchronization state of the first base station. For example, a first sequence with multiple formats is introduced, and when the first sequence is sent at the first frequency position, it indicates that the clock synchronization of the first base station is reliable; when the first sequence is sent at the second frequency position, it indicates that the clock synchronization of the first base station is reliable. The clock synchronization of a base station is unreliable; or, for example, when the first sequence is sent at different time positions or frequency positions, it indicates different clock synchronization types of the first base station. During specific implementation, the first sequence may be an NLRS sequence.

Therefore, the receiving module 11 is specifically used for:

Judging the clock synchronization state of the first base station according to the format of the sequence and a third preset rule.

In the fourth optional implementation manner, the clock synchronization status can be indicated through the preset bits of the PBCH, for example, the reliability or unreliability of the clock synchronization can be indicated through 1 bit information, or a bitmap (bitmap) can be used through X bit information ) to indicate the clock synchronization type, or to indicate the clock synchronization type in binary form through y-bit information, where X and y are integers.

Therefore, the receiving module 11 can specifically be used for:

Read the preset bits in the physical broadcast channel PBCH sent by the first base station;

Judging the clock synchronization state of the first base station according to preset bits in the PBCH and a fourth preset rule.

In a fifth optional implementation manner, a predefined synchronization level may be used to indicate a clock synchronization state. For example, the maximum synchronization level that can be supported in the system or the reserved synchronization level can be used to indicate whether the clock synchronization is reliable; or the different synchronization levels that can be supported in the system can correspond to different clock synchronization types . Further, the synchronization level can be passed through different cell identities, Different sequence formats are represented by preset bits in the PBCH.

Therefore, the receiving module 11 can specifically be used for:

reading the synchronization level sent by the first base station in the physical layer channel;

Judging the clock synchronization state of the first base station according to the synchronization level and a fifth preset rule. In a sixth optional implementation manner, the clock state information of the first base station may be obtained in a UE-assisted manner.

Therefore, the receiving module 11 can specifically be used for:

The clock synchronization state of the first base station sent by the UE is received through an uplink transmission channel, and the clock synchronization state of the first base station is sent to the UE by the first base station through a physical layer channel.

During specific implementation, one can select a signal that can simultaneously receive signals from the first base station and the second base station

As an auxiliary UE, the first base station may notify the auxiliary UE of the clock state information of the first base station through a physical layer channel, and the auxiliary UE may use an uplink transmission channel to notify the second base station of the clock state information of the first base station, wherein The time resources, frequency resources, and sequence resources occupied by the clock state information of the first base station in the uplink transmission channel may be defined in advance. Therefore, the receiving module 11 can detect whether the energy on the fixed time resource and frequency resource exceeds the set threshold to judge the clock synchronization status of the first base station, for example, whether the clock synchronization is reliable, or by checking whether the energy on the fixed time resource and frequency resource exceeds the set threshold. Different sequences are detected on frequency resources to distinguish the clock synchronization state of the first base station. The specific format of the physical layer channel occupied by the first base station notifying the assisting UE of the clock state information may also be defined in advance, or obtained through UE blind detection.

Wherein, in the fifth and sixth implementation manners, the physical layer channel may include at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, a channel carrying a system information block SIB, a paging channel, and a physical downlink control channel PDCCH, enhanced physical downlink control channel EPDCCH, physical downlink shared channel PDSCH.

FIG. 3 is a schematic structural diagram of Embodiment 2 of the clock synchronization device of the present invention. The device of this embodiment can be set on a base station, and the base station can be used as a first base station, that is, a base station that needs to update synchronization information. As shown in FIG. 3, the device 300 of this embodiment may include: a determining module 21 and a sending module 22, wherein,

The determination module 21 is configured to determine its own clock synchronization status, the clock synchronization status of the first base station includes whether the clock synchronization of the first base station is reliable and/or the clock synchronization type, and the first base station The clock synchronization type of the station includes at least one of the clock synchronization source of the first base station, the operator to which the first base station belongs, the base station type of the first base station, and the identity of the first base station;

The sending module 22 is configured to send the clock synchronization state of the first base station to the second base station, so that the second base station determines the synchronization source base station according to the clock synchronization state of the first base station, and according to the first base station The clock information of the base station is synchronized.

The clock synchronization source included in the above clock synchronization state can be, for example: the clock synchronization comes from the Global Navigation Satellite System (Global Navigation Satellite System, GNSS for short), such as GPS, Beidou satellite navigation system, or a wired network (such as IEEE1588 clock Synchronization protocol, Ethernet clock synchronization protocol), or the clock synchronization provided by the macro base station having a coverage overlapping area with the micro base station, or the clock synchronization provided by the micro base station.

The base station type of the first base station may be: a macro base station, a micro base station, a micro base station is characterized by low transmission power and a small coverage area, and a micro base station may specifically include a metro cell (Metro cell), a micro cell (Micro cell), and a pico cell (Pico cell), Femto cell (Femto cell).

The identity of the first base station may be: a base station that directly implements clock synchronization through an external synchronization source (for example, a header), a base station that does not directly implement clock synchronization through an external synchronization source (for example, a non-header), and the external synchronization source may be Clock synchronization provided by GNSS; Clock synchronization provided by cable network; Clock synchronization provided by macro base station; The base station that does not directly realize clock synchronization through an external synchronization source can be: a base station that obtains clock synchronization through a header.

It should be noted that the identity of a base station is usually for a cluster of base stations. A cluster of base stations may be a plurality of base stations densely deployed within a certain geographical area. The division of a cluster may be defined by an operator during deployment. The header in the cluster base station may be a base station that obtains clock synchronization through an external clock synchronization source in the cluster base station, and the non-header is a base station that obtains clock synchronization through the header in the cluster base station.

Whether the clock synchronization is reliable can be defined as: a base station that can obtain clock information directly through an external synchronization source or indirectly through an external synchronization source is regarded as a base station with reliable clock synchronization, wherein the clock is obtained directly through an external synchronization source The information means that the base station can directly obtain clock information from GNSS, such as GPS, Beidou satellite navigation system, or wired network (such as IEEE1588 clock synchronization protocol, Ethernet clock synchronization protocol); indirectly obtain the clock through an external synchronization source The information refers to the clock information obtained by the base station from an external synchronization source through other base stations. For example, base station A directly obtains clock synchronization through an external synchronization source, and base station B obtains clock synchronization through base station A, then the clock synchronization of base station B belongs to Synchronization information obtained indirectly through an external synchronization source, SP, can also be considered reliable. The definition of whether the clock synchronization is reliable can also be: the clock synchronization of the base station that takes into account the relative clock synchronization relationship with other base stations is considered reliable, and the clock synchronization of the base station that does not consider the relative clock synchronization relationship with other base stations Synchronization is considered unreliable.

The definition of whether clock synchronization is reliable can also be: the clock synchronization of synchronized base stations is considered reliable, and the clock synchronization of unsynchronized (or out-of-synchronization) base stations is considered unreliable.

The definition of whether the clock synchronization is reliable can also be: the clock synchronization of the base station directly or indirectly through the GNSS or wired network timing is considered reliable, and the clock synchronization of the base station not directly or indirectly passed through the GNSS or wired network timing is considered to be unsafe. Reliable, such as base stations deployed in isolation.

The first base station may include a macro base station and a micro base station, and the second base station is preferably a micro base station, but may also include a macro base station. The first base station and the second base station may belong to the same operator, or may belong to different operators.

Optionally, in a manner, the sending module 22 may specifically be used for:

Sending the clock synchronization state of the first base station by way of air interface signaling.

Optionally, in another manner, the sending module 22 may specifically be used for:

Sending the clock synchronization state of the first base station through a backhaul link; or, reporting the clock synchronization state of the first base station to a centralized controller, so that the centralized controller sends the first The clock synchronization status of the base station is sent to the second base station; or,

reporting the clock synchronization state of the first base station to the macro base station, so that the macro base station sends the clock synchronization state of the first base station to the second base station.

Wherein, the backhaul link backhaul may be an S1/X2 interface.

When the sending module 22 sends the clock synchronization state of the first base station to indicate that the clock synchronization of the first base station is reliable and/or the clock synchronization type of the first base station has a high priority, the second base station may send the second base station A base station serves as a candidate synchronization source base station or directly determines the first base station as the synchronization source base station.

The clock synchronization device in this embodiment determines its own clock synchronization state through the determining module, and sends the clock synchronization state of the first base station to the second base station through the sending module, so that the second base station to be synchronized can be in Confirm the clock synchronization state of the first base station before performing synchronization, and only after determining that the clock synchronization of the first base station is reliable and/or the clock synchronization type of the first base station has a high priority, the first base station is determined as Synchronize the source base stations, so as to avoid the problem of inaccurate synchronization of the second base station due to inaccurate clock information of the first base station, ensure that the second base station performs synchronization according to correct clock information, and improve the clock synchronization of the entire system step accuracy. Further, the sending module 22 in the above embodiment can be configured in the following six ways.

In the first optional implementation manner, the clock synchronization status is indicated by the cell ID. Therefore, the sending module 22 can specifically be used for:

sending the cell identity of the first base station to the second base station, so that the second base station judges the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule.

In a second optional implementation manner, the clock synchronization state of the first base station may be indicated by a primary synchronization sequence PSS and/or a secondary synchronization sequence SSS.

Therefore, the sending module 22 can specifically be used for:

Determine the main synchronization sequence according to its own clock synchronization state and the sixth preset rule? 88 and\or secondary synchronization sequence SSS;

sending the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS to the second base station, so that the second base station determines the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS Describe the clock synchronization state of the first base station.

In a third optional implementation manner, one or more sequences may be introduced to indicate the clock synchronization state of the first base station. The sequence can be sent through air interface signaling.

Therefore, the sending module 22 can specifically be used for:

Determine at least one sequence according to its own clock synchronization state and a second preset rule;

The sequence is sent by way of air interface signaling, so that the second base station judges the clock synchronization state of the first base station according to the sequence and the second preset rule.

Wherein, there is a preset time interval between the transmission time position of the sequence and the PSS or the SSS transmission time position, and/or the transmission frequency position of the sequence and the PSS or the SSS transmission frequency position There is a preset frequency interval between them; therefore, further specifically, the sending module 22 may be specifically configured to: send the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS to the second base station, and at least one of said sequences.

In the above-mentioned third optional implementation manner, the second base station may detect at a preset sending position and/or a preset frequency position to determine whether the sequence exists, or determine what sequence the received sequence is to determine the first sequence. Clock synchronization status of a base station.

Optionally, in addition to using the introduced sequence to indicate the clock synchronization status of the first base station, it may also be used The pattern of the sequence indicates the clock synchronization state of the first base station. For example, a first sequence with multiple formats is introduced, and when the first sequence is sent at the first frequency position, it indicates that the clock synchronization of the first base station is reliable; when the first sequence is sent at the second frequency position, it indicates that the clock synchronization of the first base station is reliable. The clock synchronization of a base station is unreliable; or, for example, when the first sequence is sent at different time positions or frequency positions, it indicates different clock synchronization types of the first base station. During specific implementation, the first sequence may be an NLRS sequence.

Therefore, the sending module 22 can specifically be used for:

determining the format of the sequence according to its own clock synchronization state and a third preset rule; sending the sequence to the second base station according to the format, so that the second base station judges the sequence according to the format of the sequence Describe the clock synchronization state of the first base station.

In a fourth optional implementation manner, the clock synchronization status may be indicated by a preset bit of the PBCH, for example, 1-bit information may be used to indicate whether the clock synchronization is reliable or unreliable, and X-bit information may be used to indicate the clock synchronization status using a bitmap (bitmap) The format indicates the clock synchronization type, or indicates the clock synchronization type in binary form through y-bit information, where X and y are integers.

Therefore, the sending module 22 can specifically be used for:

Carrying the clock synchronization state of itself in the preset bit in the physical broadcast channel PBCH; sending the physical broadcast channel PBCH to the second base station, so that the second base station according to the preset bit in the physical broadcast channel PBCH Set the bit and the fourth preset rule to judge the clock synchronization state of the first base station.

In a fifth optional implementation manner, a predefined synchronization level may be used to indicate a clock synchronization state. For example, the maximum synchronization level that can be supported in the system or the reserved synchronization level can be used to indicate whether the clock synchronization is reliable; or the different synchronization levels that can be supported in the system can correspond to different clock synchronization types . Further, the synchronization level can be represented by different cell identities, different sequence formats, and preset bits in the PBCH.

Therefore, the sending module 22 can specifically be used for:

Determine the synchronization level of the first base station according to its own clock synchronization state and a fifth preset rule;

sending the synchronization level of the first base station to the second base station on a physical layer channel, so that the second base station judges the clock of the first base station according to the synchronization level and the fifth preset rule sync state. In a sixth optional implementation manner, the clock state information of the first base station may be obtained in a UE-assisted manner.

Therefore, the sending module 22 can specifically be used for:

Sending the clock synchronization state of the first base station to the UE through a physical layer channel, so that the UE sends the clock synchronization state of the first base station to the second base station through an uplink transmission channel.

During specific implementation, a UE capable of simultaneously receiving signals from the first base station and the second base station may be selected as the auxiliary UE, and the first base station may notify the auxiliary UE of the clock state information of the first base station through a physical layer channel, and the auxiliary UE may The clock state information of the first base station is notified to the second base station by using the uplink transmission channel, wherein the time resources, frequency resources, and sequence resources occupied by the clock state information of the first base station in the uplink transmission channel may be defined in advance. Therefore, the receiving module 11 can detect whether the energy exceeds a set threshold on a fixed time resource and frequency resource, and judge the clock synchronization state of the first base station, for example, whether the clock synchronization is reliable, or it can also determine whether the clock synchronization status is reliable by using a fixed time resource and frequency resource. Different sequences are detected on the resource to distinguish the clock synchronization state of the first base station. The specific format of the physical layer channel occupied by the first base station notifying the assisting UE of the clock state information may also be defined in advance, or obtained through UE blind detection.

Wherein, in the fifth and sixth implementation manners, the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, a channel carrying a system information block SIB, a paging channel, and a physical downlink control channel PDCCH , Enhanced Physical Downlink Control Channel EPDCCH, Physical Downlink Shared Channel PDSCH.

Of course, since each base station can be used not only as a second base station to be synchronized, but also as a first base station that provides synchronization information for other base stations, the clocks used to update the synchronization information in the above-mentioned various device embodiments The synchronizing device and the clock synchronizing device for providing synchronous information can be set on a base station at the same time.

FIG. 4 is a schematic structural diagram of Embodiment 1 of a base station according to the present invention. The base station in this embodiment can be used as a second base station, that is, a base station that needs to update synchronization information. As shown in FIG. 4, the base station 400 of this embodiment may include: a receiver 401 and a transmitter 402, and a processor 403, a memory 404, and a bus 405 are also shown in the figure. The receiver 401, the transmitter 402, the processor 403 and the memory 404 are connected through the bus 405 and complete mutual communication.

The bus 405 may be an Industry Standard Architecture (Industry Standard Architecture, ISA) bus, a Peripheral Component (PCI) bus or an extended industry standard quasi-architecture (Extended Industry Standard Architecture, EISA) bus, etc. the bus

The 405 can be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, only one thick line is used in FIG. 4, but it does not mean that there is only one bus or one type of bus.

The memory 404 is used to store executable program codes including computer operation instructions. The memory 404 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

The processor 403 may be a central processing unit (Central Processing Unit, CPU), or a specific integrated circuit (Application Specific Integrated Circuit, ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention.

Wherein, the receiver 401 is configured to receive a clock synchronization state of at least one first base station; the processor 403 is configured to determine a synchronization source base station according to the clock synchronization state of the first base station; the processor 403 also uses performing synchronization according to the clock information of the synchronization source base station; wherein, the clock synchronization status includes whether the clock synchronization is reliable and/or a clock synchronization type, and the clock synchronization type of the first base station includes the first At least one of the clock synchronization source of the base station, the operator to which the first base station belongs, the base station type of the first base station, and the identity of the first base station.

The clock synchronization sources included in the above clock synchronization state can be, for example: Clock synchronization comes from Global Navigation Satellite System (Global Navigation Satellite System, GNSS for short), such as GPS, Beidou satellite navigation system, or wired network (such as IEEE1588 clock synchronization Synchronization protocol, Ethernet clock synchronization protocol), or clock synchronization provided by a macro base station that has a coverage overlapping area with a micro base station, or clock synchronization provided by a micro base station.

The base station type of the first base station may be: a macro base station, a micro base station, a micro base station is characterized by low transmission power and a small coverage area, and a micro base station may specifically include a metro cell (Metro cell), a micro cell (Micro cell), and a pico cell (Pico cell), Femto cell (Femto cell).

The identity of the first base station may be: a base station that directly implements clock synchronization through an external synchronization source (for example, a header), a base station that does not directly implement clock synchronization through an external synchronization source (for example, a non-header), and the external synchronization source may be : Clock synchronization provided by GNSS; Clock synchronization provided by wired network; Clock synchronization provided by macro base station; The base station that does not directly realize clock synchronization through an external synchronization source can be: a base station that obtains clock synchronization through a header.

It should be noted that the identity of the base station is usually for a cluster of base stations, a cluster of base stations may be multiple base stations densely deployed within a certain geographical area, and the division of the cluster may be through the operator department As defined at the time, the header in a cluster of base stations may be the base station in the cluster that acquires clock synchronization through an external clock synchronization source, and the non-header is the base station in the cluster that acquires clock synchronization through the header.

Whether the clock synchronization is reliable can be defined as: a base station that can obtain clock information directly through an external synchronization source or indirectly through an external synchronization source is regarded as a base station with reliable clock synchronization, wherein the clock is obtained directly through an external synchronization source Information means that the base station can directly obtain clock information from GNSS, such as GPS, Beidou satellite navigation system, or wired network (such as IEEE1588 clock synchronization protocol, Ethernet clock synchronization protocol); indirectly obtain the clock through an external synchronization source The information refers to the clock information obtained by the base station from an external synchronization source through other base stations. For example, base station A directly obtains clock synchronization through an external synchronization source, and base station B obtains clock synchronization through base station A, then the clock synchronization of base station B belongs to Synchronization information obtained indirectly through an external synchronization source, SP, can also be considered reliable.

The definition of whether the clock synchronization is reliable can also be: the clock synchronization of the base station that takes into account the relative clock synchronization relationship with other base stations is considered reliable, and the clock synchronization of the base station that does not consider the relative clock synchronization relationship with other base stations Synchronization is considered unreliable.

The definition of whether clock synchronization is reliable can also be: the clock synchronization of synchronized base stations is considered reliable, and the clock synchronization of unsynchronized (or out-of-synchronization) base stations is considered unreliable.

The definition of whether the clock synchronization is reliable can also be: the clock synchronization of the base station directly or indirectly through the GNSS or wired network timing is considered reliable, and the clock synchronization of the base station not directly or indirectly passed through the GNSS or wired network timing is considered to be unsafe. Reliable, such as base stations deployed in isolation.

Optionally, in a manner, the receiver 401 may specifically be used for:

Receive the clock synchronization state of the first base station by way of air interface signaling.

Optionally, in another manner, the receiver 401 may specifically be used for:

Receiving the clock synchronization state of the first base station through a backhaul link; or receiving the clock synchronization state of the first base station through a centralized controller, where the clock synchronization state of the first base station is determined by the reported by the first base station to the centralized controller; or,

The clock synchronization state of the first base station is received by the macro base station, and the clock synchronization state of the first base station is reported to the macro base station by the first base station.

Wherein, the backhaul link backhaul may be an S1/X2 interface.

Specifically, when the clock synchronization state of the first base station indicates that the clock synchronization of the first base station is reliable and/or the clock synchronization type has a high priority, the clock synchronization device in this embodiment may use the first base station The base station serves as a candidate synchronization source base station or directly determines the first base station as the synchronization source base station. Since the receiver 401 may receive the clock synchronization states of multiple first base stations, and there may be multiple first base stations with reliable clock synchronization, all of these first base stations with reliable clock synchronization can be used as candidate synchronization source base stations, and the processing The module 403 may select one of the first base stations as the synchronization source base station according to a preset rule.

Since the receiver 401 may receive the clock synchronization states of multiple first base stations, and there may be multiple first base stations with the same clock synchronization state, for example, there are multiple first base stations with reliable clock synchronization, and these reliable clock synchronization All the first base stations can be used as candidate synchronization source base stations, and the processor 403 can select one of the first base stations as the synchronization source base station according to preset rules, for example, the selection can be made according to the synchronization level, and the first base station with the smallest synchronization level is selected. The base station is used as the synchronization source base station; or, it can be selected according to the priority of the clock synchronization type, which can provide clock synchronization of the first base station with high synchronization accuracy, small synchronization error, and convenience for synchronization between different operators The type has a high priority, and the priority of the clock synchronization type can be reflected as follows: the priority of the clock source being GNSS is higher than the priority of the clock source being wired network or wireless synchronization, and the clock source being GNSS or the first base station of the wired network The priority is higher than the first base station whose clock source is wireless synchronization, and the first base station whose clock source is wireless synchronization means that the first base station realizes synchronization by receiving synchronization signals sent by other base stations; the priority of the macro base station is higher than that of the micro The priority of the base station, the priority of the first base station belonging to the same operator as the second base station is higher than that of the first base station not belonging to the same operator as the second base station (in some scenarios, it can also be set to belong to the same operator as the second base station) The priority of the first base station of the quotient is lower than that of the first base station that does not belong to the same operator as the second base station); or, if the first base station is determined to be the synchronization source base station and has the least impact on other synchronized base stations, Then such a first base station can be considered to have a high-priority clock synchronization type, and the first base station can be used as a synchronization source base station, and the impact is the least, which can mean that for a synchronized base station, it is necessary to readjust the clock synchronization The number of base stations synchronized is the least; or, the clock synchronization type priority of the first base station as header is greater than the clock synchronization type priority of the first base station as non-header, as header and/or as the first base station of non-header It may be indicated by the clock synchronization source of the first base station, or directly indicated by whether the first base station is a header or not.

For the case of multiple candidate synchronization source base stations, the second base station may also select according to other rules, which is not limited in this embodiment of the present invention.

It should be noted that the priorities corresponding to different clock synchronization types can be defined by standard protocol specifications, or can be implemented by network side configuration, for example, by OAM configuration, or by macro base station configuration, or by the base station side. The behavior of is not limited here, so that the first base station and\or the second base station can know each other.

In the base station of this embodiment, after the receiver receives the clock synchronization state of the first base station, the processor determines the synchronization source base station according to the clock synchronization state of the first base station, and then performs synchronization based on the synchronization source base station, that is It can be realized that the clock synchronization state of the first base station is first confirmed before synchronization, and only after determining that the clock synchronization of the first base station is reliable and/or the type of clock synchronization has a high priority, the first base station is determined as Synchronize the source base stations, so as to avoid the problem of inaccurate synchronization of the second base station due to inaccurate clock information of the first base station, ensure that the second base station performs synchronization according to correct clock information, and improve the clock synchronization of the entire system step accuracy.

Further, the receiver 401 may be configured in the following six ways.

In the first optional implementation manner, the clock synchronization status is indicated by the cell ID. Therefore, the receiver 401 can specifically be used for:

receiving a cell identity of at least one first base station;

Judging the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule.

In a second optional implementation, the primary synchronization sequence PSS and/or the secondary synchronization sequence

The SSS is used to indicate the clock synchronization state of the first base station.

Therefore, the receiver 401 can specifically be used for:

receiving the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS sent by the first base station;

According to the master synchronization sequence? 88 and/or the secondary synchronization sequence SSS to determine the cell identity of the first base station.

In a third optional implementation manner, one or more sequences may be introduced to indicate the clock synchronization state of the first base station. The sequence can be sent through air interface signaling.

Therefore, the receiver 401 can specifically be used for:

receiving the sequence sent by the first base station, and judging the clock synchronization state of the first base station according to the sequence and a second preset rule.

During specific implementation, the receiver 401 may specifically be used for:

The second base station receives the primary synchronization sequence sent by the first base station? 88 and/or a secondary synchronization sequence SSS, and at least one sequence, there is a preset time interval between the sending time position of the sequence and the sending time position of the PSS or the SSS, and/or the sending of the sequence There is a preset frequency interval between the frequency position and the PSS or the SSS sending frequency position. Optionally, in addition to using the imported sequence to indicate the clock synchronization state of the first base station, the format of the sequence may also be used to indicate the clock synchronization state of the first base station.

Therefore, the receiver 401 can specifically be used for:

Judging the clock synchronization state of the first base station according to the format of the sequence and a third preset rule.

In the fourth optional implementation, the clock synchronization status can be indicated through the preset bit of the PBCH, for example, the reliability or unreliability of the clock synchronization can be indicated through lbit information, or a bitmap (bitmap) can be used through X bit information The form of indicates the clock synchronization type, or indicates the clock synchronization type in binary form through y-bit information, where X and y are integers.

Therefore, the receiver 401 can specifically be used for:

Read the preset bits in the physical broadcast channel PBCH sent by the first base station;

Judging the clock synchronization state of the first base station according to preset bits in the PBCH and a fourth preset rule.

In a fifth optional implementation manner, a predefined synchronization level may be used to indicate a clock synchronization state. For example, the maximum synchronization level that can be supported in the system or the reserved synchronization level can be used to indicate whether the clock synchronization is reliable; or the different synchronization levels that can be supported in the system can correspond to different clock synchronization types . Further, the synchronization level can be represented by different cell identities, different sequence formats, and preset bits in the PBCH.

Therefore, the receiver 401 can specifically be used for:

reading the synchronization level sent by the first base station in the physical layer channel;

Judging the clock synchronization state of the first base station according to the synchronization level and a fifth preset rule. In a sixth optional implementation manner, the clock state of the first base station may be learned in a UE-assisted manner.

Therefore, the receiver 401 can specifically be used for:

The clock synchronization state of the first base station sent by the UE is received through an uplink transmission channel, and the clock source synchronization state of the first base station is sent to the UE by the first base station through a physical layer channel.

During specific implementation, a UE capable of simultaneously receiving signals from the first base station and the second base station may be selected as the auxiliary UE, and the first base station may notify the auxiliary UE of the clock state information of the first base station through a physical layer channel, and the auxiliary UE may Using the uplink transmission channel, the clock state of the first base station The information is notified to the second base station, wherein the time resources, frequency resources, and sequence resources occupied by the clock state information of the first base station in the uplink transmission channel may be defined in advance. Therefore, the receiver 401 can detect whether the energy exceeds a set threshold on a fixed time resource and frequency resource to judge the clock synchronization status of the first base station, for example, whether the clock synchronization is reliable, or can be determined by using a fixed time resource and frequency resource. Different sequences are detected on the resource to distinguish the clock synchronization state of the first base station. The specific format of the physical layer channel occupied by the first base station notifying the assisting UE of the clock state information may also be defined in advance, or obtained through UE blind detection.

Wherein, in the fifth and sixth implementation manners, the physical layer channel may include at least one of the following: a physical broadcast channel PBCH, a channel carrying a system information block SIB, a paging channel, a physical downlink control channel PDCCH, an enhanced physical Downlink Control Channel EPDCCH, Physical Downlink Shared Channel PDSCH.

FIG. 5 is a schematic structural diagram of Embodiment 2 of the base station of the present invention. The base station in this embodiment can be used as the first base station, that is, the base station that provides synchronization information. As shown in FIG. 5, the base station 500 of this embodiment may include: a receiver 501 and a transmitter 502, and a processor 503, a memory 504, and a bus 505 are also shown in the figure. The receiver 501, the transmitter 502, the processor 503 and the memory 504 are connected through the bus 505 and complete mutual communication.

The bus 505 may be an Industry Standard Architecture (Industry Standard Architecture, ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (Extended Industry Standard Architecture, EISA) bus, etc. The bus 505 can be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, only one thick line is used in Fig. 5, but it does not mean that there is only one bus or one type of bus.

The memory 504 is used to store executable program codes including computer operation instructions. The memory 504 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

The processor 503 may be a central processing unit (Central Processing Unit, CPU), or a specific integrated circuit (Application Specific Integrated Circuit, ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention.

Wherein, the processor 503 may be configured to determine its own clock synchronization state, where the clock synchronization state of the first base station includes whether the clock synchronization of the first base station is reliable and/or a clock synchronization type, and the first base station The clock synchronization type of a base station includes the clock synchronization source of the first base station, the slave station of the first base station At least one of the operator of the first base station, the base station type of the first base station, and the identity of the first base station; the transmitter 502 may be configured to send the clock synchronization status of the first base station to the second base station, so that the second base station Determine a synchronization source base station according to the clock synchronization state of the first base station, and perform synchronization according to clock information of the first base station.

The clock synchronization source included in the above clock synchronization state can be, for example: the clock synchronization comes from the Global Navigation Satellite System (Global Navigation Satellite System, GNSS for short), such as GPS, Beidou satellite navigation system, or a wired network (such as IEEE1588 clock Synchronization protocol, Ethernet clock synchronization protocol), or the clock synchronization provided by the macro base station having a coverage overlapping area with the micro base station, or the clock synchronization provided by the micro base station.

The base station type of the first base station may be: a macro base station, a micro base station, a micro base station is characterized by low transmission power and a small coverage area, and a micro base station may specifically include a metro cell (Metro cell), a micro cell (Micro cell), and a pico cell (Pico cell), Femto cell (Femto cell).

The identity of the first base station may be: a base station that directly implements clock synchronization through an external synchronization source (for example, a header), a base station that does not directly implement clock synchronization through an external synchronization source (for example, a non-header), and the external synchronization source may be Clock synchronization provided by GNSS; Clock synchronization provided by cable network; Clock synchronization provided by macro base station; The base station that does not directly realize clock synchronization through an external synchronization source can be: a base station that obtains clock synchronization through a header.

It should be noted that the identity of a base station is usually for a cluster of base stations, a cluster of base stations may be multiple base stations densely deployed within a certain geographical area, and the division of clusters may be defined by operators during deployment. The header in the base station may be a base station that obtains clock synchronization through an external clock synchronization source in the cluster base station, and the non-header is a base station that obtains clock synchronization through the header in the cluster base station.

Whether the clock synchronization is reliable can be defined as: a base station that can obtain clock information directly through an external synchronization source or indirectly through an external synchronization source is regarded as a base station with reliable clock synchronization, wherein the clock is obtained directly through an external synchronization source Information means that the base station can directly obtain clock information from GNSS, such as GPS, Beidou satellite navigation system, or wired network (such as IEEE1588 clock synchronization protocol, Ethernet clock synchronization protocol); indirectly obtain clock information through an external synchronization source It means that the base station obtains clock information of an external synchronization source through other base stations. For example, base station A directly obtains clock synchronization through an external synchronization source, and base station B obtains clock synchronization through base station A, so the clock synchronization of base station B belongs to indirect Synchronization information acquired through an external synchronization source, SP, can also be considered reliable.

Whether the clock synchronization is reliable can also be defined as: Will consider the relative clock synchronization with other base stations The clock synchronization of base stations with a synchronization relationship is considered reliable, and the clock synchronization of base stations that do not consider the relative clock synchronization relationship with other base stations is considered unreliable.

The definition of whether clock synchronization is reliable can also be: the clock synchronization of synchronized base stations is considered reliable, and the clock synchronization of unsynchronized (or out-of-synchronization) base stations is considered unreliable.

The definition of whether the clock synchronization is reliable can also be: the clock synchronization of the base station directly or indirectly through the GNSS or wired network timing is considered reliable, and the clock synchronization of the base station not directly or indirectly passed through the GNSS or wired network timing is considered to be unsafe. Reliable, such as base stations deployed in isolation.

Optionally, in a manner, the transmitter 502 may specifically be used for:

The first base station sends the clock synchronization state of the first base station by way of air interface signaling. Optionally, in another manner, the transmitter 502 may specifically be used for:

Sending the clock synchronization state of the first base station through a backhaul link; or, reporting the clock synchronization state of the first base station to a centralized controller, so that the centralized controller sends the first The clock synchronization status of the base station is sent to the second base station; or,

reporting the clock synchronization state of the first base station to the macro base station, so that the macro base station sends the clock synchronization state of the first base station to the second base station.

Wherein, the backhaul link backhaul may be an S1/X2 interface.

Specifically, when the clock synchronization status of the first base station indicates that the clock synchronization of the first base station is reliable and/or the clock synchronization type has a high priority, the base station in this embodiment may use the first base station as a candidate The synchronization source base station may directly determine the first base station as the synchronization source base station.

The base station in this embodiment sends its own clock synchronization state to the second base station after determining its own clock synchronization state, so that the second base station can determine the synchronization source base station according to the clock synchronization state of the first base station , then perform synchronization based on the synchronization source base station, that is, enable the second base station to confirm the clock synchronization state of the first base station before performing synchronization, so as to avoid the second For the problem of inaccurate synchronization of the base stations, ensuring that the second base station performs synchronization according to correct clock information can improve the accuracy of clock synchronization of the entire system.

Further, the transmitter 502 can be configured in the following six ways.

In the first optional implementation manner, the clock synchronization status is indicated by the cell ID. Therefore, the transmitter 502 can specifically be used for:

sending the cell identity of the first base station to the second base station, so that the second base station judges the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule state.

In a second optional implementation manner, the clock synchronization state of the first base station may be indicated by a primary synchronization sequence PSS and/or a secondary synchronization sequence SSS.

Therefore, the transmitter 502 can specifically be used for:

Determine the main synchronization sequence according to its own clock synchronization state and the sixth preset rule? 88 and\or secondary synchronization sequence SSS;

sending the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS to the second base station, so that the second base station determines the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS The cell identifier of the first base station.

In a third optional implementation manner, one or more sequences may be introduced to indicate the clock synchronization state of the first base station. The sequence can be sent through air interface signaling.

Therefore, the transmitter 502 can specifically be used for:

Determine at least one sequence according to its own clock synchronization state and a second preset rule;

The sequence is sent by way of air interface signaling, so that the second base station judges the clock synchronization state of the first base station according to the sequence and the second preset rule.

During specific implementation, a preset time interval can be set between the sending time position of the sequence and the sending time position of the PSS or the SSS, and/or the sending frequency position of the sequence and the PSS or the SSS There is a preset frequency interval between SSS transmission frequency positions;

The transmitter 502 can specifically be used for:

Sending the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS, and at least one sequence to the second base station.

Optionally, in addition to using the imported sequence to indicate the clock synchronization state of the first base station, the format of the sequence may also be used to indicate the clock synchronization state of the first base station.

Therefore, the transmitter 502 can specifically be used for:

determining the format of the sequence according to its own clock synchronization state and a third preset rule; sending the sequence to the second base station according to the format, so that the second base station judges the sequence according to the format of the sequence Describe the clock synchronization state of the first base station.

In the fourth optional implementation manner, the clock synchronization status can be indicated through the preset bit of the PBCH, for example, the reliability or unreliability of the clock synchronization can be indicated through 1 bit information, and the clock synchronization status can be indicated in the form of a bitmap through X bit information. Step type, or when indicated in binary form by y-bit information Clock synchronization type, x and y are integers respectively.

Therefore, the transmitter 502 can specifically be used for:

Carrying the clock synchronization state of itself in the preset bit in the physical broadcast channel PBCH; sending the physical broadcast channel PBCH to the second base station, so that the second base station according to the preset bit in the physical broadcast channel PBCH Set the bit and the fourth preset rule to judge the clock synchronization state of the first base station.

In a fifth optional implementation manner, a predefined synchronization level may be used to indicate a clock synchronization state. For example, the maximum synchronization level that can be supported in the system or the reserved synchronization level can be used to indicate whether the clock synchronization is reliable; or the different synchronization levels that can be supported in the system can correspond to different clock synchronization types . Further, the synchronization level can be represented by different cell identities, different sequence formats, and preset bits in the PBCH.

Therefore, the transmitter 502 can specifically be used for:

Determine the synchronization level of the first base station according to its own clock synchronization state and a fifth preset rule;

sending the synchronization level of the first base station to the second base station on a physical layer channel, so that the second base station judges the clock of the first base station according to the synchronization level and the fifth preset rule sync state.

In a sixth optional implementation manner, the clock state of the first base station may be learned in a UE-assisted manner.

Therefore, the transmitter 502 can specifically be used for:

Sending the clock synchronization state of the first base station to the UE through a physical layer channel, so that the UE sends the clock synchronization state of the first base station to the second base station through an uplink transmission channel.

During specific implementation, a UE capable of simultaneously receiving signals from the first base station and the second base station may be selected as the auxiliary UE, and the first base station may notify the auxiliary UE of the clock status information of the first base station through a physical layer channel, and the auxiliary UE may The clock state information of the first base station is notified to the second base station by using the uplink transmission channel, wherein the time resources, frequency resources, and sequence resources occupied by the clock state information of the first base station in the uplink transmission channel may be defined in advance. Therefore, the second base station can detect whether the energy exceeds the set threshold on fixed time resources and frequency resources to determine whether the clock synchronization of the first base station is reliable, or detect different sequences on fixed time resources and frequency resources , to distinguish the clock synchronization state of the first base station. The first base station notifies the secondary UE clock The specific format of the physical layer channel occupied by the state information can also be defined in advance, or through

Obtained by UE blind detection.

Wherein, in the fifth and sixth implementation manners, the physical layer channel may include at least one of the following: a physical broadcast channel PBCH, a channel carrying a system information block SIB, a paging channel, a physical downlink control channel PDCCH, an enhanced Physical downlink control channel EPDCCH, physical downlink shared channel PDSCH.

FIG. 6 is an interaction flowchart of Embodiment 1 of the clock synchronization method of the present invention. In this embodiment, the first base station is a base station that provides clock synchronization information, and the second base station is a base station to be synchronized. As shown in FIG. 6, the clock synchronization method in this embodiment may be as follows.

Step 601, the first base station determines its own clock synchronization status.

Wherein, the clock synchronization state includes whether the clock synchronization is reliable and/or the clock synchronization type, and the clock synchronization type of the first base station may include the clock synchronization source of the first base station, the operator to which the first base station belongs , at least one of the base station type of the first base station, and the identity of the first base station.

The clock synchronization source included in the above clock synchronization state can be, for example: the clock synchronization comes from the global navigation satellite system GNSS, such as GPS, Beidou satellite navigation system, or a wired network (such as IEEE1588 clock synchronization protocol, Ethernet clock synchronization protocol ), or clock synchronization provided by a macro base station that has a coverage overlapping area with a micro base station, or clock synchronization provided by a micro base station. The base station type of the first base station can be: macro base station, micro base station, and micro base station. The transmission power is low and the coverage area is small, and the micro base station may specifically include a metro cell (Metro cell), a micro cell (Micro cell), a pico cell (Pico cell), and a femto cell (Femto cell).

The identity of the first base station may be: a base station that directly implements clock synchronization through an external synchronization source (for example, a header), a base station that does not directly implement clock synchronization through an external synchronization source (for example, a non-header), and the external synchronization source may be Clock synchronization provided by GNSS; Clock synchronization provided by cable network; Clock synchronization provided by macro base station; The base station that does not directly realize clock synchronization through an external synchronization source can be: a base station that obtains clock synchronization through a header.

It should be noted that the identity of a base station is usually for a cluster of base stations, a cluster of base stations may be multiple base stations densely deployed within a certain geographical area, and the division of clusters may be defined by operators during deployment. The header in the base station may be a base station that obtains clock synchronization through an external clock synchronization source in the cluster base station, and the non-header is a base station that obtains clock synchronization through the header in the cluster base station.

Whether the clock synchronization is reliable can be defined as: Will be able to directly pass through an external synchronization source or indirectly A base station that obtains clock information through an external synchronization source is considered to be a base station with reliable clock synchronization. The clock information directly obtained through an external synchronization source means that the base station can directly obtain clock information from GNSS, such as GPS, Beidou satellite navigation system, or A wired network (such as IEEE1588 clock synchronization protocol, Ethernet clock synchronization protocol) obtains clock information; indirectly obtaining clock information through an external synchronization source means that the base station obtains clock information of an external synchronization source through other base stations, such as base station A The clock synchronization is obtained directly through the external synchronization source, and the base station B obtains the clock synchronization through the base station A, then the clock synchronization of the base station B belongs to the synchronization information obtained indirectly through the external synchronization source, and the SP can also be considered reliable .

The definition of whether the clock synchronization is reliable can also be: the clock synchronization of the base station that takes into account the relative clock synchronization relationship with other base stations is considered reliable, and the clock synchronization of the base station that does not consider the relative clock synchronization relationship with other base stations Synchronization is considered unreliable.

The definition of whether clock synchronization is reliable can also be: the clock synchronization of synchronized base stations is considered reliable, and the clock synchronization of unsynchronized (or out-of-synchronization) base stations is considered unreliable.

The definition of whether the clock synchronization is reliable can also be: the clock synchronization of the base station directly or indirectly through the GNSS or wired network timing is considered reliable, and the clock synchronization of the base station not directly or indirectly passed through the GNSS or wired network timing is considered to be unsafe. Reliable, such as base stations deployed in isolation.

The first base station may include a macro base station and a micro base station, and the second base station is preferably a micro base station, but may also include a macro base station. The first base station and the second base station may belong to the same operator, or may belong to different operators.

Step 602. The first base station sends the clock synchronization state of the first base station to the second base station. Correspondingly, the second base station receives the clock synchronization state of the first base station.

In step 602, the manner in which the second base station receives the clock synchronization status of the first base station may be implemented by the second base station through network listening (network listening), or through a backhaul link (backhaul), or It may be in a manner assisted by user equipment (User Equipment, UE for short).

Optionally, in an implementation manner, step 602 may be: the first base station sends the clock synchronization state of the first base station through air interface signaling.

This manner may be applicable to a scenario where the first base station and the second base station belong to different operators, and is also applicable to a scenario where the first base station and the second base station belong to the same operator.

Optionally, in another implementation manner, the first base station sends the clock synchronization state of the first base station by means of a backhaul link backhaul; or, The first base station reports the clock synchronization state of the first base station to a centralized controller, so that the centralized controller sends the clock synchronization state of the first base station to the second base station; or, The first base station reports the clock synchronization state of the first base station to the macro base station, so that the macro base station sends the clock synchronization state of the first base station to the second base station.

When the clock synchronization state is sent by the macro base station, the following two situations may occur:

In the first case, a macro base station is used for transmission between the first base station and the second base station. Specifically, the first base station reports the clock synchronization state of the first base station to a macro base station that has a wireless interface or a wired interface with the first base station, for example, it may be a macro base station that has a coverage overlapping area with the first base station, so that the macro base station sends the clock synchronization state of the first base station to the second base station.

In the second case, the transmission between the first base station and the second base station passes through two macro base stations. Specifically, the first base station reports the clock synchronization state of the first base station to a first macro base station that has a wireless interface or a wired interface with the first base station, for example, it may be the first macro base station that has a coverage overlapping area with the first base station. A macro base station, so that the first macro base station sends the clock synchronization status of the first base station to the second macro base station, so that the second macro base station synchronizes the clock of the first base station The status is sent to the second base station. During this process, the data transmission between the first macro base station and the second macro base station may also be forwarded by the centralized controller.

Wherein, sending the clock synchronization state of the first base station through the backhaul link may be applicable to a scenario where the first base station and the second base station belong to the same operator; sending the clock synchronization state of the first base station through the centralized controller may be applicable In a scenario where the first base station and the second base station belong to different operators.

Wherein, the backhaul link backhaul may be an S1/X2 interface.

Step 603, the second base station determines the synchronization source base station according to the clock synchronization state of the first base station. Specifically, when the clock synchronization state of the first base station indicates that the clock synchronization of the first base station is reliable and/or indicates that the clock synchronization type of the first base station has a high priority, the second base station may set the The first base station serves as a candidate synchronization source base station or directly determines the first base station as the synchronization source base station.

Because in step 602, the second base station may receive the clock synchronization states of multiple first base stations, and there may be multiple first base stations with reliable clock synchronization, these first base stations with reliable clock synchronization can all be used as candidates for synchronization. The second base station may select a first base station as the synchronization source base station according to a preset rule, for example, it may select according to the synchronization level, and select the first base station with the smallest synchronization level as the synchronization source base station; or, It can be selected according to the priority of the clock synchronization type, and the first base station that can provide high synchronization accuracy, small synchronization error, and facilitate synchronization between different operators The clock synchronization type has a high priority, and the priority of the clock synchronization type can be reflected as follows: The clock source is

The priority of GNSS is higher than the priority of the clock source being wired network or wireless synchronization, the priority of the first base station whose clock source is GNSS or wired network is higher than the first base station whose clock source is wireless synchronization, and the clock source is wireless synchronization The first base station means that the first base station realizes synchronization by receiving synchronization signals sent by other base stations; the priority of the macro base station is higher than the priority of the micro base station, and the priority of the first base station belonging to the same operator as the second base station Greater than the first base station that does not belong to the same operator as the second base station (in some scenarios, it can also be set that the priority of the first base station that belongs to the same operator as the second base station is lower than that of the first base station that does not belong to the same operator as the second base station a base station); or, if it is determined that the first base station is the synchronization source base station and has the least impact on other synchronized base stations, then the first base station may be used as the synchronization source base station, and the impact is the smallest, which may be It means that for the synchronized base stations, the number of base stations that need to readjust the clock synchronization is the least; or, the priority of the first base station as a header is higher than the priority of the first base station as a non-header, as a header and/or as a non-header The first base station of the header may be marked by the clock synchronization source of the first base station, or directly marked by whether the first base station is a header or not. It can also be selected according to other rules, which is not limited in this embodiment of the present invention.

It should be noted that the priorities corresponding to different clock synchronization types can be configured by the network side, or can be implemented by the base station side, which is not limited here, so that the first base station and/or the second base station can know each other .

Step 604, the second base station performs synchronization according to the clock information of the synchronization source base station.

In this embodiment, after the first base station determines its own clock synchronization state, it sends the clock synchronization state to the second base station, and the second base station determines the synchronization source base station according to the clock synchronization state of the first base station, and then Synchronization is performed based on the synchronization source base station, that is, the second base station can first confirm the clock synchronization state of the first base station before performing synchronization, and only when it is determined that the clock synchronization of the first base station is reliable and/or the clock of the first base station The first base station is determined as the synchronization source base station only after the synchronization type has a high priority, thereby avoiding the problem of inaccurate synchronization of the second base station due to inaccurate clock information of the first base station, and ensuring that the second base station Performing synchronization according to correct clock information can improve the accuracy of clock synchronization of the entire system.

Further, in step 602 of the first embodiment above, the first base station sends the clock synchronization state of the first base station to the second base station, and the following six implementation manners may be adopted.

In a first optional implementation manner, through a cell identity (cell identity, cell ID for short), to indicate the clock synchronization status.

Specifically, the above step 602 may include:

The first base station sends the cell identity of the first base station to the second base station; the second base station judges the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule . That is, the cell ID of the first base station carries information about whether clock synchronization is reliable. The cell ID may be represented by a PCI (Physical Cell Identification), or an Evolved UMTS Terrestrial Radio Access Network (Evolved UMTS Terrestrial Radio Access Network) cell global identification ECGI (E-UTRAN Cell Global Identifier) ), or in other ways, as long as the cell identity of the first base station can be used to ensure that the first base station can be uniquely determined in scenarios of the same operator and/or different operators. . For example, assuming that the set of all cell IDs is N, some cell IDs are taken from the set N to form a set M, obviously, M is a proper subset of N. The cell ID included in M is used to indicate that the clock synchronization of the first base station is unreliable, and the cell ID that does not belong to the set M is used to indicate that the clock synchronization of the first base station is reliable; or, the cell ID included in M is used to indicate that the clock synchronization of the first base station is not reliable; The clock synchronization of a base station is reliable, and the cell ID that does not belong to the set M is used to indicate that the clock synchronization of the first base station is unreliable.

The cell ID used to indicate that the clock synchronization is reliable and/or unreliable can be known by the second base station in a predefined manner, or by the first base station and the second base station, for example, it can be realized through factory settings; or through a centralized controller For example, it may be realized by configuration of Operations administration and maintenance (Operations administration and maintenance, OAM for short); or, it may be realized through configuration of a centralized controller such as a Mobility management entity (MME for short); or, it may also be realized through other centralized controllers such as coordinator or E-coordinator (Enhanced coordinator) configuration; or, it can also be implemented by configuring a macro base station with a wireless or wired interface with the first base station and the second base station, where the macro base stations can be the same or different , The "wireless interface" here means that the macro base station can notify the second base station, or the first base station and the second base station, of the cell ID indicating whether the clock synchronization is reliable or unreliable through air interface signaling, and the "wired interface" here "Interface" can be S1 interface, X2 interface.

If the first base station and/or the second base station know the set of cell IDs used to indicate reliable clock synchronization through the above predefined manner, the full set of cell IDs that the system can support can be used (for example, for the LTE system, if the cell ID uses PCI to means, then the full set of cell IDs includes 504 different cPCIs), and the set of cell IDs used to indicate unreliable clock synchronization is deduced; similarly, if the first base The station or the second base station obtains the set of cell IDs used to indicate unreliable clock synchronization through the above predefined manner, and can use the full set of cell IDs that the system can support (for example, for the LTE system, if the cell ID is represented by PCI, then the cell The full set of IDs includes 504 different PCIs, and a set of cell IDs used to indicate reliable clock synchronization is derived.

There are two methods for the first base station to determine its cell ID as follows:

In the first possible manner, the first base station may determine the cell ID according to its own clock synchronization state and the known set of cell IDs indicating that the clock synchronization state is reliable or unreliable;

In the second possible way, the first base station can be configured directly according to the clock synchronization state of the first base station through a centralized controller and a macro base station having a wireless or wired interface with the first base station. For the second possible way , Optionally, the centralized controller and the macro base station that has a wireless or wired interface with the first base station first need to know the clock synchronization status of the first base station. For example, the first base station may report the clock synchronization state of the first base station to the centralized controller and the macro base station having a wireless or wired interface with the first base station, so that it can learn the clock synchronization state of the first base station.

After the second base station receives the cell ID of the first base station, it can judge whether the cell ID of the first base station belongs to the cell ID indicating that the clock synchronization is reliable, and if so, it can judge that the clock synchronization state of the first base station is Reliable; if not, it can be judged that the clock synchronization state of the first base station is unreliable.

It should be noted that in this implementation manner, the second base station receives at least one cell identity of the first base station through air interface signaling or backhaul, which is not limited in this embodiment of the present invention.

Similarly, in the above first optional implementation manner, the clock synchronization type may also be indicated by the cell ID. Since the clock synchronization type may include at least one of the clock synchronization source, the operator to which the first base station belongs, the base station type of the first base station, and the identity of the first base station, specifically, it may be specified that the cell ID and various clock synchronization The corresponding relationship between step sources, or the corresponding relationship between the cell ID and the operator to which the base station belongs, or the corresponding relationship between the cell ID and the base station type, or the corresponding relationship between the cell ID and the first base station whether it is a header or a non-header relation.

During specific implementation, one method is: a part of the cell ID can be reserved to indicate that the clock synchronization source is GNSS, a part of the cell ID indicates that the clock synchronization source is a wired network, and a part of the cell ID indicates that the clock synchronization source is a macro base station. In this way, the first The second base station can determine the clock synchronization source of the first base station according to the cell ID of the first base station, thereby judging whether the first base station can be used as the synchronization source base station; one method is: assigning different cell IDs to different operators , for example, a base station belonging to the first operator Using the cell ID in the first range, in this way, the second base station can determine the operator to which the first base station belongs according to the cell ID of the first base station, thereby judging whether the first base station can be used as a synchronization source base station; The operator's base station uses the cell ID within the second range; another method is to use different types of base stations to allocate different cell IDs, so that the second base station can determine the type of the first base station according to the cell ID of the first base station, so that Judging whether the first base station can be used as a synchronization source base station;

Another method is: assigning different cell IDs to first base stations with different identities, for example, for a base station that directly implements clock synchronization through an external synchronization source or a header in a cluster of base stations, a cell ID within a first range is used , for a base station that does not directly implement clock synchronization through an external synchronization source or a non-header in a cluster of base stations, a cell ID in the second range is used, where a cluster of base stations can be densely deployed in a certain geographical area. A base station, the division of the cluster can be defined by the operator during deployment, the header here can be a base station that obtains clock synchronization through an external clock synchronization source in a cluster of base stations, and the non-header is a base station that obtains clock through a header in a cluster of base stations Synchronized base stations.

Because the cell identity can be composed of a primary synchronization sequence (Primary synchronization sequence, PSS for short) and/or a secondary synchronization sequence (Secondary synchronization sequence, SSS for short). In the existing LTE specification, there are a total of 504 PCIs, wherein the composition of the PCIs can be expressed in the form of physical cell identity=physical cell identity group (PCI group)×the number IDs in each identity group (the number IDs in each group), That is, the 504 physical cell identifiers can be divided into 168 physical cell identifier groups, and each physical cell identifier group includes three identification numbers. Therefore, the reservation of the cell ID (for example, PCI) can also be realized by reserving a cell ID group (for example, a physical cell identity group) or reserving the number IDs in each group. Equivalently, it can be indicated by reserving SSS for PCI group or PSS for indicating the number IDs in each group.

Specifically, the process of the first base station sending the cell identity of the first base station may be as follows:

Step 1. The first base station determines the cell identity of the first base station according to its own clock synchronization state and a first preset rule;

Step 2: The first base station determines a primary synchronization sequence PSS and/or a secondary synchronization sequence SSS according to the cell identity.

During specific implementation, the first base station may first determine its cell identity according to the above method, and then determine the primary synchronization sequence PSS and/or the secondary synchronization sequence sss according to the cell identity.

Step 3: The first base station sends the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS to the second base station. Step 4: The second base station determines the cell identity of the first base station according to the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS.

During the search process of the synchronization source base station, the second base station may determine the cell ID of the first base station by reading the PSS and/or SSS sent by the first base station, and then determine the cell ID between the predefined cell ID and the clock synchronization state. The corresponding relationship is to determine the clock synchronization status of the first base station. If the second base station determines that the clock synchronization of the first base station is reliable and/or the type of clock synchronization has a high priority, the second base station may use the first base station as Candidate synchronization source base stations, or directly use the first base station as the synchronization source base station.

In addition, for sending the cell ID of the first base station, in addition to using the air interface, a backhaul link may also be used. The cell identity can be ECGI marked by higher layers. When the backhaul link is adopted, the process in which the first base station interacts with the second base station and the second base station determines the clock synchronization state of the first base station may be as follows:

Step 1. The first base station determines the cell according to its own clock synchronization status and a first preset rule.

ID.

Step 2: The first base station sends the cell ID to the second base station through a backhaul link.

Step 3: The second base station determines the clock synchronization state of the first base station according to the cell ID.

Wherein, the cell ID is sent to the second base station by means of a backhaul link, and in specific implementation, the cell ID may be sent to the second base station through a centralized controller, or the cell ID may be sent to the second base station through a macro base station The second base station sends the cell ID.

It should be noted that, in the above two implementation manners, if the first base station and the second base station belong to different operators, optionally, different operators need to interact with each other through negotiation or paper agreement or other methods. Or it is determined to reserve the cell ID information, so that base stations of different operators have the same understanding of the corresponding relationship between the cell ID and the clock synchronization state.

In a second optional implementation manner, for step 602 of the first method embodiment above, the clock synchronization status of the first base station may be indicated directly by reserving the PSS and/or SSS.

In the first optional implementation above, it is also described that the clock synchronization type is indicated by PSS and SSS (constituting a cell ID), but in the second optional implementation, directly by PSS and \ or SSS indicates the clock synchronization state, and the cell identity is not involved here.

In specific implementation, it can be stipulated that only one of PSS and SSS is used to directly indicate the clock synchronization The clock synchronization type can also be indicated by both the PSS and the SSS. Specifically, the method for the second base station to determine the clock synchronization state of the first base station may be as follows (the description is made by specifying that only the PSS is used to indicate the clock synchronization type as an example):

Step 1. The first base station determines the primary synchronization sequence PSS of the first base station according to its own clock synchronization state and a sixth preset rule.

Step 2: The first base station sends the primary synchronization sequence PSS of the first base station to the second base station. It should be noted that, in the actual sending process, usually the first base station sends the PSS and the SSS together. Step 3: The second base station determines the clock synchronization state of the first base station according to the primary synchronization sequence PSS of the first base station.

When it is specified that SSS is used to indicate the clock synchronization type, or when both PSS and SSS are specified to indicate the clock synchronization type, the method is similar, and only the PSS in the above three steps needs to be changed to SSS, or to PSS and SSS is enough, so no more details are given here.

The method of using only one of PSS and SSS, or using PSS and SSS to directly indicate the clock synchronization type at the same time, can also be through the air interface or the backhaul link.

It should be noted that, in the above-mentioned second optional implementation manner, if the first base station and the second base station belong to different operators, optionally, the different operators need to be negotiated or through a paper agreement or In other manners, information about the reserved PSS or SSS is exchanged or determined, so that base stations of different operators have a consistent understanding of the corresponding relationship between the PSS or SSS and the clock synchronization state.

The second base station can judge whether the first base station can be used as the clock source base station according to the clock synchronization type. At this time, the clock synchronization type is indicated by PSS and SSS. The specific implementation method is the same as that introduced in the first optional implementation mode. The method of indicating the type of clock synchronization through the cell ID is similar, and will not be repeated here.

In a third optional implementation manner, for step 602 of the above method embodiment, one or more sequences may be introduced to indicate the clock synchronization state of the first base station. The sequence can be sent through air interface signaling.

Specifically, step 602 of the above method embodiment may include:

Step 1. The first base station determines at least one sequence according to its own clock synchronization state and a second preset rule;

Step 2. The first base station sends the sequence through air interface signaling;

Step 3, the second base station judges the first base station according to the sequence and the second preset rule The clock synchronization status of the base station.

There is a preset time interval between the sending time position of the sequence and the PSS or the SSS sending time position, and/or between the sending frequency position of the sequence and the PSS or the SSS sending frequency position With preset frequency intervals. On the one hand, the second base station may indicate the clock synchronization state by whether the sequence exists at the determined time position and the determined frequency position, for example, indicating whether the clock synchronization is reliable; on the other hand, the second base station may also determine the Different sequences of time positions and determined frequency positions exist to indicate clock synchronization status.

Therefore, the above step 2 may include: the first base station sending the primary synchronization sequence PSS and/or secondary synchronization sequence SSS, and at least one of the sequences to the second base station.

The transmission pattern (pattern) of the sequence may include a transmission time position, a transmission frequency position, and a sequence form, and the transmission format may be directly known to the first base station and the second base station in a predefined manner, and the predefined specific implementation manner may include any of the following One or a combination thereof: factory settings of the first base station and the second base station, a centralized controller such as OAM configuration, MME configuration, coordinator or Ε-coOTdinatOT configuration, or, a macro base with a wireless or wired interface with the first base station and the second base station station configuration.

The transmission frequency position of the sequence may be indicated by having a certain frequency interval with the PSS or SSS transmission frequency position, or may be determined by having a certain frequency separation and sequence transmission bandwidth with the PSS or SSS transmission frequency position, These parameters may also be known by the first base station and the second base station in a predefined manner. The form of the sequence can be obtained in at least one of the following ways, generated by a pseudo-random sequence, or generated by a Zadoff-Chu sequence, or generated by a machine-generated sequence, for example, the sequence form of the sequence can be different from that used in the existing LTE system The 4th PSS sequence out of the 3 PSS sequences. Specifically, the sending frequency position can be indicated by any one of the following methods: represented by an occupied subcarrier index; represented by an occupied resource block (RB, Resource Block) index. For example, the determined frequency interval can be expressed as a specific subcarrier index or a specific RB index relative to the PSS or SSS transmission frequency position, the number of offset subcarriers or the number of RBs, and the transmission bandwidth of the sequence can be an integer number of subcarriers It is represented by a carrier or an integer number of RBs.

The sending time position of the sequence may be indicated by having a certain time interval with the PSS or SSS sending time position; it may also be indicated by a specific period and a subframe offset within this period. Specifically, the sending time position of the sequence can be indicated by any of the following methods: represented by an OFDM index number; represented by a subframe index number and an OFDM index number; represented by a radio frame Indicated by an index number, a subframe index number, and an OFDM index number; Indicated by a time slot index number and an OFDM index number; Indicated by a radio frame index number, a time slot index number, and an OFDM index number. The determined time interval can be represented by N OFDM symbols. When this indication method is used, if the OFDM index number determined through the time interval is not within the range of OFDM index numbers (0~13) in a subframe or is no longer one The OFDM index number in the time slot indicates that the OFDM symbol determined by the time interval is not in the current subframe or in the current time slot.

The following uses a frequency division duplex (FDD, Frequency Division Duplex) system as an example to illustrate the specific implementation of the implementation method. It should be noted that the method can also be applied to the TDD system.

Figure 7 is a schematic diagram of the time-frequency distribution of PSS and SSS in the FDD system, as shown in Figure 7, the bearer

The primary synchronization channel (Primary synchronization channel, P-SCH for short) of the PSS and the secondary synchronization channel (Secondary synchronization channel, S-SCH for short) carrying the SSS are distributed in the middle 6 RBs of the entire system bandwidth in the frequency domain In terms of time, it is sent every 5ms. For the FDD system, P-SCH and S-SCH are sent in subframe 0 and subframe 5, and are respectively located in the 5th OFDM symbol and the 6th OFDM symbol in the subframe . In the LTE system, one RB is a time-frequency resource block composed of 12 subcarriers and 7 OFDM symbols.

Based on FIG. 7, the position with a certain time interval with the PSS transmission time position can be understood as the position with a certain time interval with the time position of the P-SCH carrying the PSS (that is, the fifth OFDM symbol). As mentioned above, if The time position of PSS transmission is represented by M (in this example, M=5), and the determined time interval is represented by N OFDM symbols, then M+N represents the transmission time position of the sequence, and N can be a positive integer or negative Integer, specifically, if the maximum value of the OFDM symbol index supported by the system is considered to be K, then the OFDM index number where the transmission time position of the sequence is determined can be determined by "(M+N) MOD K", using (M+N) /K Rounding down determines the relationship between the subframe index number where the OFDM symbol where the transmission time position of the sequence is located and the subframe index number where the PSS is located. The specific example is as follows: For example, M=5, N=3, K=14, then (M+N) MOD K=8, (M+N)/K rounded down=0, it means that the sending time position of the sequence Located in the #8th OFDM symbol in the same subframe as the PSS; another example is M=5, N=9, K=14, belj (M+N) MOD K=0, (M+N) /K is rounded down=1, which means that the sending time position of the sequence is at the 0th OFDM symbol of the next subframe of the subframe where the PSS is located.

Based on Figure 7, and the position of the PSS transmission frequency has a certain frequency interval, for example, the PSS transmission frequency The highest frequency point in the sending frequency position is used as the reference (indicated by A), and the frequency interval is represented by an integer number of subcarriers (indicated by B), then the highest frequency point in the sending frequency position of the sequence can be determined as A+B or the lowest frequency point It is determined as A+B, specifically indicating the highest frequency point or the lowest frequency point, which can be realized in a predefined manner. Then through the sending bandwidth, the sending frequency position of the sequence can be determined.

It should be noted that, in the above description, the PSS transmission is taken as an example, and the determination of the transmission time position and transmission frequency position of the sequence based on the SSS transmission time position and transmission frequency position is the same as the PSS description.

In addition, in the existing LTE system, the PSS and SSS are sent twice in each radio frame. In order to save the system overhead on the first base station side, the sequence is determined by having a certain time interval and frequency interval with the PSS or SSS The method for sending the time position and the frequency time position can further specify that the sequence only appears once in each radio frame.

It should be noted that, in the above-mentioned third optional implementation manner, the second base station may detect at a preset sending position and/or a preset frequency position, and determine whether the sequence exists, or determine whether the sequence received Why sequence to judge the clock synchronization state of the first base station.

Further, in addition to using the imported sequence to indicate the clock synchronization state of the first base station, a pattern of the sequence may also be used to indicate the clock synchronization state of the first base station. For example, a first sequence with multiple formats is introduced, and when the first sequence is sent at the first frequency position, it indicates that the clock synchronization of the first base station is reliable; when the first sequence is sent at the second frequency position, it indicates that the clock synchronization of the first base station is reliable. The clock synchronization of a base station is unreliable; or, for example, when the first sequence is sent at different time positions or frequency positions, it indicates different clock synchronization types of the first base station. Specifically, step 602 of the method embodiment may include:

Step 1. The first base station determines the format of the sequence according to its own clock synchronization state and a third preset rule;

Step 2, the first base station sends the sequence to the second base station according to the format; Step 3, the second base station judges the clock synchronization state of the first base station according to the format of the sequence .

The first base station may determine, according to its own clock synchronization state and a known sequence format, where the sequence format includes at least one of a transmission time position, a transmission frequency position, and a sequence form, whether to determine whether to transmit at a specified transmission time position and transmission frequency The location sending sequence, or different sending pattern forms of the sequence are determined to indicate the clock synchronization state. For example, if the clock synchronization of the first base station is reliable, the first base station can transmit the sequence according to a preset transmission pattern; on the contrary, if the first base station clock synchronization is unreliable, the first base station may not send the sequence according to the preset sending pattern. Of course, the preset sending pattern may also be used to indicate that the clock synchronization is unreliable. At this time, if the clock synchronization of the first base station is reliable, the first base station may not send the sequence according to the preset sending pattern.

The second base station can learn the correspondence between the clock synchronization state and the format of the sequence in a predefined manner. During the search process of the synchronization source base station, the second base station obtains the timing position of the first base station by reading the PSS and SSS sent by the first base station, and determines the cell ID of the first base station, and then detects the sequence according to the third preset rule . The second base station determines the clock synchronization state of the first base station by detecting whether there is a sequence or a different transmission pattern of the sequence. It should be noted that, since the second base station can only determine the frame boundary of the sending time of the first base station by reading the PSS and SSS sent by the first base station, that is, the 10ms boundary, therefore, if the sending period of the predefined indicated sequence exceeds 10ms The second base station also needs to read the physical broadcast channel (Physical broadcast channel, PBCH for short) sent by the first base station to determine the system frame number (System frame number, SFN for short) of the first base station, thereby determining the transmission time of the sequence Location.

It should be noted that, if the first base station and the second base station belong to different operators, optionally, different operators may determine the sequence to send the pattern information and the sequence to be synchronized with the clock through negotiation or paper agreement or other means. Correspondence between synchronization states, so that base stations of different operators have a consistent understanding of the correspondence between sequence transmission patterns and clock synchronization states.

During specific implementation, the format (NLRS pattern) of the predefined network listening reference signal NLRS may be used to indicate the clock synchronization status. The NLRS pattern includes a sending time position, a sending frequency position, and a sending sequence form of the NLRS. The sending time position, sending frequency position, and sending sequence form of the NLRS may adopt the method introduced in this implementation. For example, the NLRS sent in the Nth subframe in the Mth radio frame indicates that the clock synchronization is reliable, and the NLRS sent in the Kth subframe in the Mth radio frame indicates that the clock synchronization is unreliable, where M, N, K is an integer not less than 0, and N and K may be equal or unequal. If N and K are equal, then it can also be confirmed whether the clock synchronization is reliable through the frequency position sent by the NLRS in the N (or K) th subframe.

The first base station may determine the NLRS pattern to be sent according to the third preset rule according to its own synchronization state, or may also use a centralized controller (such as OAM, MME) and a macro base station having a wireless or wired interface with the first base station The station is directly configured according to the clock synchronization state of the first base station and implemented according to the third preset rule. When the method of implementing through configuration is adopted, the centralized controller and the macro base station that has a wireless or wired interface with the first base station first need to know that the second Clock synchronization status of a base station. For example, The first base station may report the clock synchronization state of the first base station to the centralized controller, and the macro base station having a wireless or wired interface with the first base station first learns the clock synchronization state of the first base station.

The second base station can learn the correspondence between the NLRS pattern and the clock synchronization state in a predefined manner. During the search process of the synchronization source base station, the second base station determines the timing information and frequency information of the signal sent by the first base station by reading the PSS and SSS sent by the first base station, and then, according to the predefined NLRS pattern, determines the possible existing The NLRS pattern sends the position, and detects whether the NLRS pattern used to indicate the clock synchronization state exists through blind detection. If the reserved transmission period of the NLRS pattern used to indicate whether the clock is synchronized exceeds 10ms, then the second base station also needs to read the PBCH of the first base station to determine the system frame number SFN of the first base station, thereby determining the reserved NLRS pattern sending time position. Then the second base station judges the clock synchronization state of the first base station according to the format of the sequence and a third preset rule.

In addition, in the above-mentioned third optional implementation manner, the clock synchronization type may also be indicated by a sequence or a sequence format. Since the clock synchronization type may include at least one of the clock synchronization source, the operator to which the first base station belongs, the base station type of the first base station, and the identity of the first base station, specifically, the sequence may be specified, or the The corresponding relationship between the format of the sequence and various clock synchronization sources, or specify the sequence, or the corresponding relationship between the format of the sequence and the operator to which the base station is subordinate, or specify the sequence, or the format of the sequence The corresponding relationship with the base station type.

During specific implementation, one method is: a first sequence may be introduced to represent that the source of clock synchronization is GNSS, a second sequence represents that the source of clock synchronization is a wired network, and a third sequence represents that the source of clock synchronization is a macro base station. In this way, the first sequence The second base station can determine the clock synchronization source of the first base station according to the sequence sent by the first base station. Of course, only one sequence can be introduced, and different clock synchronization sources can be distinguished through different formats of the sequence, so as to determine whether the clock synchronization source of the first base station can be The first base station is used as the synchronization source base station; one method is: assigning different sequences to different operators, for example, the base station subordinate to the first operator adopts the fourth sequence, so that the second base station can determine the second sequence according to the sequence An operator to which a base station belongs, thereby judging whether the first base station can be used as a synchronization source base station; a base station subordinate to a second operator adopts a cell ID within a second range; another method is to use different types of base stations to allocate Different sequences, in this way, the second base station can determine the type of the first base station according to the sequence of the first base station, so as to judge whether the first base station can be used as the synchronization source base station. Another method is: assigning different cell IDs to first base stations with different identities, for example, for a base station that directly implements clock synchronization through an external synchronization source or a header in a cluster of base stations, a cell ID within a first range is used , for indirect external The base station that realizes clock synchronization or the non-header in a cluster of base stations adopts the cell ID in the second range, where a cluster of base stations can be a plurality of base stations densely deployed in a certain geographical area, and the division of clusters can be It is defined by the operator during deployment. The header here may be a base station that obtains clock synchronization through an external clock synchronization source in a cluster of base stations, and the non-header is a base station that obtains clock synchronization through a header in a cluster of base stations.

In a fourth optional implementation manner, for step 602 of the above method embodiment, the bit carried by the PBCH can be used to indicate the clock synchronization status in the form of a bitmap (bitmap) or in a binary form, for example, the status can be indicated by The lbit information indicates the clock synchronization state.

Which bit contained in the PBCH and the corresponding relationship between the different content indicated by the bit and the clock synchronization state can be known by the first base station and the second base station in a predefined manner.

Specifically, step 602 of the above method embodiment may include:

Step 1. The first base station carries its own clock synchronization state in the preset bits in the physical broadcast channel PBCH;

Step 2, the first base station sends the physical broadcast channel PBCH to the second base station; Step 3, the second base station judges according to the preset bits in the physical broadcast channel PBCH and the fourth preset rule The clock synchronization state of the first base station.

The first base station can determine the specific indication content of the bit used to indicate whether the clock synchronization is reliable and/or the clock synchronization type in the PBCH according to its own clock synchronization state, for example, 1 represents reliable, 0 represents unreliable, or 1 It means unreliable, and 0 means reliable; or, the clock synchronization type can be indicated in the form of a bitmap (bitmap) through X-bit information, or the clock synchronization type can be indicated in binary form through y-bit information, where X, y are integer.

The second base station may learn in a predefined manner the correspondence between the indication content of the preset bit and the clock synchronization state, that is, the fourth preset rule. During the search process of the synchronization source base station, the second base station obtains the clock synchronization information of the first base station by reading the PSS and SSS sent by the first base station, and then obtains the clock synchronization information for the first base station by receiving and analyzing the PBCH sent by the first base station. Content indicated by the bit indicating the clock synchronization state, and then judge the clock synchronization state of the first base station. The second base station executes the synchronization source base station search process, which may be executed when the second base station is just turned on, or the second base station searches for the synchronization source again.

It should be noted that, if the first base station and the second base station belong to different operators, optionally, different operators also need to exchange or determine the PBCH through negotiation or paper agreement or other methods. The position of the bit used to indicate the clock synchronization state and the corresponding relationship between the content indicated by the bit and the clock synchronization state, so that the base stations of different operators have a unified understanding of the bit position and the content indicated by the bit.

In addition, in the above fourth optional implementation manner, the clock synchronization type may also be indicated through a preset bit carried by the PBCH. Since the clock synchronization type may include at least one of the source of clock synchronization, the operator to which the first base station belongs, the base station type of the first base station, and the identity of the first base station, specifically, it may be specified that the preset bits are related to each The corresponding relationship between the clock synchronization sources, or the corresponding relationship between the preset bits and the operator to which the base station belongs, or the corresponding relationship between the preset bits and the base station type.

During specific implementation, different clock synchronization types may be indicated in the form of a bitmap, or different clock synchronization types may be indicated in a binary form. For example, 2-bit information may be used to indicate 4 different clock synchronization states in binary form, or 2-bit information may be used to indicate 2 different clock synchronization states in the form of a bitmap. One method is: the first type indicated by the preset bit, such as 00, can be used, and the content indicates that the source of clock synchronization is GNSS; the second type of content indicated by the preset bit, such as 01, indicates that the source of clock synchronization is a wired network. The third content indicated by the preset bit, such as 11, represents that the clock synchronization source is the macro base station, so that the second base station can determine the clock synchronization source of the first base station according to the content of the preset bit, thereby judging whether the clock synchronization source can be The first base station is used as a synchronization source base station; one method is: use a preset bit to indicate the information of the operator to which the base station belongs, so that the second base station can determine the operator to which the first base station belongs according to the preset bit, thereby judging Whether the first base station can be used as the synchronization source base station; another method is to use a preset bit to indicate the type of the base station, so that the second base station can determine the type of the first base station according to the preset bit of the first base station, thereby judging Whether the first base station can be used as a synchronization source base station. Another method is to use preset bits to indicate the identity of the base station, such as 1 for header and 0 for non-header, or use 1 for non-header and 0 for header, and send PBCH.

In a fifth optional implementation manner, for step 602 of the above method embodiment, the clock synchronization status may be indicated by a predefined synchronization level. For example, the maximum synchronization level that can be supported in the system or the reserved synchronization level can be used to indicate whether the clock synchronization is reliable; or the different synchronization levels that can be supported in the system can correspond to different clock synchronization types . Further, the synchronization level can be represented by different cell identities, different sequence formats, and preset bits in the PBCH.

Specifically, step 602 of the above method embodiment may include: Step 1. The first base station determines the synchronization level of the first base station according to its own clock synchronization state and a fifth preset rule;

Step 2, the first base station sends the synchronization level of the first base station to the second base station on a physical layer channel;

Step 3: The second base station judges the clock synchronization state of the first base station according to the synchronization level and the fifth preset rule.

The first base station selects an appropriate synchronization level according to its own synchronization state and the corresponding relationship between the learned synchronization level and the indicated clock synchronization state (that is, the fifth preset rule). Alternatively, the centralized controller and the macro base station having a wireless or wired interface with the first base station may be used to directly configure the synchronization level of the first base station according to the clock synchronization state of the first base station. When this configuration is adopted, It is also required that the centralized controller and the macro base station having a wireless or wired interface with the first base station first obtain the clock synchronization status of the first base station. For example, the first base station may report the clock synchronization state of the first base station to the centralized controller, and the macro base station having a wireless or wired interface with the first base station first obtains the clock synchronization state of the first base station.

The first base station may add the synchronization level to an existing physical layer channel for transmission, and the physical layer channel may be any of the following: PBCH, a channel carrying a system information block (System Information Block, SIB for short), paging Channel (Paging), Physical Downlink Control Channel (Physical Downlink Control Channel, PDCCH for short), Enhanced PDCCH (Enhanced PDCCH), Physical Downlink Data Channel (Physical Downlink Data Channel, PDSCH for short), or can also be attached to different NLRS Among patterns, different NLRS patterns may represent different synchronization levels. Of course, other manners may also be used, which are not limited in this embodiment of the present invention.

The second base station may learn the correspondence between the clock synchronization state and the synchronization level in a predefined manner; further, the second base station may also learn in a predefined way how the first base station sends the synchronization level, What channel is used to send the synchronization level information as described above; or, the first base station may notify the second base station of the manner of sending the synchronization level by means of signaling.

During the search process of the synchronization source base station, the second base station judges the clock synchronization state of the first base station by reading the synchronization level sent by the first base station, and the learned correspondence between the synchronization level and the clock synchronization state .

It should be noted that, if the first base station and the second base station belong to different operators, optionally, different operators also need to determine the synchronization level and timing through negotiation or paper agreement or other methods. Correspondence between clock synchronization states, so that base stations of different operators understand which synchronization levels are used to indicate clock synchronization reliability and/or unreliability, and which synchronization levels are used to indicate which clock synchronization types unanimous.

In specific implementation, the current synchronization level can be extended, and different synchronization levels can be set for different clock synchronization sources; different levels can be set for different operators; different synchronization levels can be set for different base station types ; Or set different synchronization levels for base stations with different identities. And it can be set that the smaller the synchronization level, the higher the reliability of the clock synchronization.

In a sixth optional implementation manner, for step 602 of the above method embodiment, the second base station may also be informed of the clock status of the first base station in a UE-assisted manner.

Specifically, the above step 602 may include:

Step 1. The first base station sends the clock synchronization state of the first base station to the UE through a physical layer channel.

Wherein, the physical layer channels include: a synchronization channel SCH, a physical broadcast channel PBCH, a channel carrying a system information block SIB, a paging channel, a physical downlink control channel PDCCH, an enhanced physical downlink control channel EPDCCH, and a physical downlink shared channel PDSCH .

Step 2: The UE sends the clock synchronization state of the first base station to the second base station through an uplink transmission channel.

During specific implementation, a UE capable of simultaneously receiving signals from the first base station and the second base station may be selected as the auxiliary UE, and the first base station may notify the auxiliary UE of the clock state information of the first base station through a physical layer channel, and the auxiliary UE may The clock state information of the first base station is notified to the second base station by using the uplink transmission channel, wherein the time resources, frequency resources, and sequence resources occupied by the clock state information of the first base station in the uplink transmission channel may be defined in advance. Therefore, the second base station can detect whether the energy exceeds the set threshold on fixed time resources and frequency resources to judge the clock synchronization state of the first base station, or detect different sequences on fixed time resources and frequency resources, to distinguish the clock synchronization state of the first base station. The specific format of the physical layer channel occupied by the first base station notifying the assisting UE of the clock state information may also be defined in advance, or obtained through UE blind detection.

It should be noted that the predefined specific implementation manners described in each embodiment or various implementation manners of the present invention may include any one or combination of the following: factory settings of the first base station and the second base station, OAM configuration, MME configuration, other centralized controllers such as coordinator or E-coordinator configuration, or configuration of a macro base station having wireless or wired interfaces with the first base station and the second base station.

It should be noted that the information transmission between the first base station and the second base station in each embodiment or various implementation manners of the present invention, for example, when transmitting cdl ID, sequence, synchronization level and other information or other information, can be An air interface or a backhaul link is used. More specifically, the interaction may be performed directly through the air interface or the backhaul link, or may be transmitted through a centralized controller or through a macro base station.

It should be noted that the definition of whether the clock synchronization is reliable, the priority of different clock synchronization types, and various preset rules for determining the clock synchronization state (such as the first preset rule, the second preset rule, and Defined by a standard protocol specification, it may also be implemented by network side configuration, for example, by OAM configuration, or by macro base station configuration, or it may be a behavior implemented by the base station side, such as a factory setting, so that the first base station and/or the second base station Mutual knowledge. Different operators can define the above content through negotiation or paper agreement, so as to ensure that base stations belonging to different operators have a consistent understanding of the above content.

Those of ordinary skill in the art can understand that all or part of the steps for implementing the above-mentioned method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, Executing the steps of the above-mentioned method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk, and other various media that can store program codes.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (60)

Claims 1. A clock synchronization device, comprising: A receiving module, configured to receive a clock synchronization state of at least one first base station; a determining module, configured to determine a synchronization source base station according to the clock synchronization state of the first base station; a synchronization module, configured to perform synchronization according to clock information of the synchronization source base station; Wherein, the clock synchronization state includes whether the clock synchronization is reliable and/or the clock synchronization type, and the clock synchronization type of the first base station includes the clock synchronization source of the first base station, the operator to which the first base station belongs, At least one of the base station type of the first base station and the identity of the first base station. 2. The device according to claim 1, wherein the receiving module is specifically configured to: receive the clock synchronization status of the first base station through air interface signaling. 3. The device according to claim 1, wherein the receiving module is specifically configured to: receive the clock synchronization status of the first base station through a backhaul link; or receive the clock synchronization status of the first base station through a centralized controller. A clock synchronization state of the first base station, where the clock synchronization state of the first base station is reported to the centralized controller by the first base station; or, The clock synchronization state of the first base station is received by the macro base station, and the clock synchronization state of the first base station is reported to the macro base station by the first base station. 4. The device according to any one of claims 1 to 3, wherein the receiving module is specifically used for: receiving a cell identity of at least one first base station; Judging the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule. 5. The device according to claim 2, wherein the receiving module is specifically configured to: receive the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS sent by the first base station; According to the master synchronization sequence? 88 and/or the secondary synchronization sequence SSS and the sixth preset rule to determine the cell identity of the first base station. 6. The device according to claim 2, wherein the receiving module is specifically configured to: receive the sequence sent by the first base station, and judge the clock of the first base station according to the sequence and a second preset rule sync state. 7. The device according to claim 6, wherein the receiving module is specifically configured to: receive, by the second base station, the primary synchronization sequence sent by the first base station? 88 and\or secondary synchronization sequence SSS, and at least one sequence, there is a preset time interval between the sending time position of the sequence and the PSS or the SSS sending time position, and/or the sending frequency position of the sequence is the same as the PSS or the SSS There is a preset frequency interval between the SSS sending frequency positions. 8. The device according to claim 6 or 7, wherein the receiving module is specifically used for: Judging the clock synchronization state of the first base station according to the format of the sequence and a third preset rule. 9. The device according to claim 2, wherein the receiving module is specifically configured to: read preset bits in the physical broadcast channel PBCH sent by the first base station; Judging the clock synchronization state of the first base station according to preset bits in the PBCH and a fourth preset rule. 10. The device according to claim 2, wherein the receiving module is specifically configured to: read the synchronization level sent by the first base station in the physical layer channel; Judging the clock synchronization state of the first base station according to the synchronization level and a fifth preset rule. 11. The device according to claim 2, wherein the receiving module is specifically configured to: receive the clock synchronization state of the first base station sent by the UE through an uplink transmission channel, and the clock of the first base station The source synchronization state is sent to the UE by the first base station through a physical layer channel. 12. The device according to claim 10 or 11, wherein the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, and a bearer system information block Channels of the SIB, a paging channel, a physical downlink control channel PDCCH, an enhanced physical downlink control channel EPDCCH, and a physical downlink shared channel PDSCH. 13. A clock synchronization device, comprising: A determination module, configured to determine its own clock synchronization status, where the clock synchronization status of the first base station includes whether the clock synchronization of the first base station is reliable and/or the type of clock synchronization, where the clock synchronization status of the first base station The synchronization type includes at least one of the clock synchronization source of the first base station, the operator to which the first base station belongs, the base station type of the first base station, and the identity of the first base station; A sending module, configured to send the clock synchronization state of the first base station to a second base station, so that the second base station determines a synchronization source base station according to the clock synchronization state of the first base station, and according to the first base station The clock information is synchronized. 14. The device according to claim 13, wherein the sending module is specifically configured to: send the clock synchronization state of the first base station through air interface signaling. 15. The device according to claim 13, wherein the sending module is specifically configured to: send the clock synchronization status of the first base station through a backhaul link; or, send the clock synchronization status of the first base station to reporting the clock synchronization state to the centralized controller, so that the centralized controller sends the clock synchronization state of the first base station to the second base station; or, reporting the clock synchronization state of the first base station to the macro base station, so that the macro base station sends the clock synchronization state of the first base station to the second base station. 16. The device according to any one of claims 13-15, wherein the sending module is specifically used for: sending the cell identity of the first base station to the second base station, so that the second base station judges the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule. 17. The device according to claim 14, wherein the sending module is specifically configured to: determine the master synchronization sequence according to its own clock synchronization state and the sixth preset rule? 88 and\or secondary synchronization sequence SSS; sending the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS to the second base station, so that the second base station determines the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS The cell identifier of the first base station. 18. The device according to claim 14, wherein the sending module is specifically configured to: determine at least one sequence according to its own clock synchronization state and a second preset rule; The sequence is sent by way of air interface signaling, so that the second base station judges the clock synchronization state of the first base station according to the sequence and the second preset rule. 19. The device according to claim 18, characterized in that, There is a preset time interval between the sending time position of the sequence and the PSS or the SSS sending time position, and/or between the sending frequency position of the sequence and the PSS or the SSS sending frequency position with preset frequency intervals; The sending module is specifically used for: Sending the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS, and at least one sequence to the second base station. 20. The device according to claim 18 or 19, wherein the sending module is specifically used for: determining the format of the sequence according to its own clock synchronization state and a third preset rule; sending the sequence to the second base station according to the format, so that the second base station judges the sequence according to the format of the sequence Describe the clock synchronization state of the first base station. 21. The device according to claim 14, wherein the sending module is specifically configured to: carry its own clock synchronization state in preset bits in the physical broadcast channel PBCH; send to the second base station The physical broadcast channel PBCH, so that the second base station judges the clock synchronization state of the first base station according to preset bits in the physical broadcast channel PBCH and a fourth preset rule. 22. The device according to claim 14, wherein the sending module is specifically configured to: determine the synchronization level of the first base station according to its own clock synchronization state and a fifth preset rule; sending the synchronization level of the first base station to the second base station on a physical layer channel, so that the second base station judges the clock of the first base station according to the synchronization level and the fifth preset rule sync state. 23. The device according to claim 14, wherein the sending module is specifically configured to: send the clock synchronization state of the first base station to the UE through a physical layer channel, so that the UE passes through an uplink transmission channel sending the clock synchronization state of the first base station to the second base station. 24. The device according to claim 22 or 23, wherein the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, a channel carrying a system information block SIB, a paging channel, a physical Downlink control channel PDCCH, enhanced physical downlink control channel EPDCCH, physical downlink shared channel PDSCH. 25. A base station, comprising: a receiver, configured to receive a clock synchronization state of at least one first base station, a processor, configured to determine a synchronization source base station according to the clock synchronization state of the first base station; the processor is also configured to perform synchronization according to clock information of the synchronization source base station; Wherein, the clock synchronization state includes whether the clock synchronization is reliable and/or the clock synchronization type, and the clock synchronization type of the first base station includes the clock synchronization source of the first base station, the operator to which the first base station belongs, At least one of the base station type of the first base station and the identity of the first base station. 26. The base station according to claim 25, wherein the receiver is specifically configured to: receive the clock synchronization state of the first base station through air interface signaling. 27. The base station according to claim 25, wherein the receiver is specifically configured to: receive the clock synchronization status of the first base station through a backhaul link; or receive the clock synchronization status of the first base station through a centralized controller. A clock synchronization state of the first base station, where the clock synchronization state of the first base station is reported to the centralized controller by the first base station; or, The clock synchronization state of the first base station is received by the macro base station, and the clock synchronization state of the first base station is reported to the macro base station by the first base station. 28. The base station according to any one of claims 25-27, wherein the receiver is specifically used for: receiving a cell identity of at least one first base station; Judging the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule. 29. The base station according to claim 26, wherein the receiver is specifically configured to: receive the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS sent by the first base station; According to the master synchronization sequence? 88 and/or the secondary synchronization sequence SSS and the sixth preset rule to determine the cell identity of the first base station. 30. The base station according to claim 26, wherein the receiver is specifically configured to: receive the sequence sent by the first base station, and judge the clock of the first base station according to the sequence and a second preset rule sync state. 31. The base station according to claim 30, wherein the receiver is specifically configured to: receive a primary synchronization sequence PSS and/or a secondary synchronization sequence SSS sent by the first base station, and at least one sequence, There is a preset time interval between the sending time position of the sequence and the PSS or the SSS sending time position, and/or between the sending frequency position of the sequence and the PSS or the SSS sending frequency position With preset frequency intervals. 32. The base station according to claim 30 or 31, wherein the receiver is specifically used for: Judging the clock synchronization state of the first base station according to the format of the sequence and a third preset rule. 33. The base station according to claim 26, wherein the receiver is specifically used for: Read the preset bits in the physical broadcast channel PBCH sent by the first base station; Judging the clock synchronization state of the first base station according to preset bits in the PBCH and a fourth preset rule. 34. The base station according to claim 26, wherein the receiver is specifically configured to: read the synchronization level sent by the first base station in a physical layer channel; Judging the clock synchronization state of the first base station according to the synchronization level and a fifth preset rule. 35. The base station according to claim 26, wherein the receiver is specifically configured to: receive the clock synchronization state of the first base station sent by the UE through an uplink transmission channel, and the clock source of the first base station The synchronization state is sent by the first base station to the UE through a physical layer channel. 36. The base station according to claim 34 or 35, wherein the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, a channel carrying a system information block SIB, a paging channel, a physical Downlink control channel PDCCH, enhanced physical downlink control channel EPDCCH, physical downlink shared channel PDSCH. 37. A clock synchronization base station, comprising: A processor, configured to determine its own clock synchronization state, where the clock synchronization state of the first base station includes whether the clock synchronization of the first base station is reliable and/or the type of clock synchronization, where the clock synchronization state of the first base station The synchronization type includes at least one of the clock synchronization source of the first base station, the operator to which the first base station belongs, the base station type of the first base station, and the identity of the first base station; A transmitter, configured to send the clock synchronization state of the first base station to a second base station, so that the second base station determines a synchronization source base station according to the clock synchronization state of the first base station, and according to the first base station The clock information is synchronized. 38. The base station according to claim 37, wherein the sender is specifically configured to: send the clock synchronization state of the first base station by way of air interface signaling. 39. The base station according to claim 37, wherein the transmitter is specifically configured to: transmit the clock synchronization state of the first base station through a backhaul link; or, send the clock synchronization state of the first base station to reporting the clock synchronization state to the centralized controller, so that the centralized controller sends the clock synchronization state of the first base station to the second base station; or, reporting the clock synchronization state of the first base station to the macro base station, so that the macro base station sends the clock synchronization state of the first base station to the second base station. 40. The base station according to any one of claims 37-39, wherein the transmitter is specifically used for: sending the cell identity of the first base station to the second base station, so that the second base station judges the clock synchronization state of the first base station according to the cell identity of the first base station and a first preset rule. 41. The base station according to claim 38, wherein the transmitter is specifically configured to: determine the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS according to its own clock synchronization state and a sixth preset rule ; Sending the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS to the second base station, so that the second base station uses the primary synchronization sequence? 88 and/or the secondary synchronization sequence SSS to determine the cell identity of the first base station. 42. The base station according to claim 38, wherein the transmitter is specifically configured to: determine at least one sequence according to its own clock synchronization state and a second preset rule; The sequence is sent by way of air interface signaling, so that the second base station judges the clock synchronization state of the first base station according to the sequence and the second preset rule. 43. The base station according to claim 42, characterized in that, There is a preset time interval between the sending time position of the sequence and the PSS or the SSS sending time position, and/or between the sending frequency position of the sequence and the PSS or the SSS sending frequency position with preset frequency intervals; The transmitter is specifically used for: Sending the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS, and at least one sequence to the second base station. 44. The base station according to claim 42 or 43, wherein the transmitter is specifically used for: determining the format of the sequence according to its own clock synchronization state and a third preset rule; sending the sequence to the second base station according to the format, so that the second base station judges the sequence according to the format of the sequence Describe the clock synchronization state of the first base station. 45. The base station according to claim 38, wherein the transmitter is specifically configured to: carry its own clock synchronization state in preset bits in the physical broadcast channel PBCH; send to the second base station The physical broadcast channel PBCH, so that the second base station according to The preset bit and the fourth preset rule in the physical broadcast channel PBCH judge the clock synchronization state of the first base station. 46. The base station according to claim 38, wherein the transmitter is specifically configured to: determine the synchronization level of the first base station according to its own clock synchronization state and a fifth preset rule; sending the synchronization level of the first base station to the second base station on a physical layer channel, so that the second base station judges the clock of the first base station according to the synchronization level and the fifth preset rule sync state. 47. The base station according to claim 38, wherein the sender is specifically configured to: send the clock synchronization state of the first base station to the UE through a physical layer channel, so that the UE passes through an uplink transmission channel sending the clock synchronization state of the first base station to the second base station. 48. The base station according to claim 46 or 47, wherein the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, a channel carrying a system information block SIB, a paging channel, a physical Downlink control channel PDCCH, enhanced physical downlink control channel EPDCCH, physical downlink shared channel PDSCH. 49. A clock synchronization method, comprising: the second base station receives at least one clock synchronization status of the first base station, The second base station determines the synchronization source base station according to the clock synchronization status of the first base station; The second base station performs synchronization according to the clock information of the synchronization source base station; Wherein, the clock synchronization state includes whether the clock synchronization is reliable and/or the clock synchronization type, and the clock synchronization type of the first base station includes the clock synchronization source of the first base station, the operator to which the first base station belongs, At least one of the base station type of the first base station and the identity of the first base station. 50. The method according to claim 49, wherein the second base station receiving at least one clock synchronization state of the first base station includes: The second base station receives the clock synchronization state of the first base station through air interface signaling. 51. The method according to claim 49, wherein the second base station receiving at least one clock synchronization state of the first base station includes: The second base station receives the clock synchronization state of the first base station through a backhaul link; or, The second base station receives the clock synchronization status of the first base station through a centralized controller, the The clock synchronization state of the first base station is reported to the centralized controller by the first base station; or, the second base station receives the clock synchronization state of the first base station through the macro base station, and the first base station The clock synchronization state of the base station is reported to the macro base station by the first base station. 52. The method according to any one of claims 49-51, wherein the second base station receiving at least one clock synchronization state of the first base station includes: The second base station receives at least one cell identity of the first base station; The second base station judges the clock synchronization status of the first base station according to the cell identity of the first base station and a first preset rule. 53. The method according to claim 50, wherein the second base station receiving at least one cell identity of the first base station comprises: The second base station receives the primary synchronization sequence sent by the first base station? 88 and\or secondary synchronization sequence SSS; The second base station according to the primary synchronization sequence? 88 and/or the secondary synchronization sequence SSS and the sixth preset rule determine the cell identity of the first base station. 54. The method according to claim 50, wherein the second base station receives the clock synchronization state of the first base station through air interface signaling, comprising: The second base station receives the sequence sent by the first base station, and judges the clock synchronization state of the first base station according to the sequence and a second preset rule. 55. The method according to claim 54, wherein the second base station reads the sequence sent by the first base station, comprising: The second base station receives the primary synchronization sequence sent by the first base station? 88 and/or a secondary synchronization sequence SSS, and at least one sequence, there is a preset time interval between the sending time position of the sequence and the sending time position of the PSS or the SSS, and/or the sending of the sequence There is a preset frequency interval between the frequency position and the PSS or the SSS sending frequency position. 56. The method according to claim 54 or 55, wherein the second base station judges the clock synchronization state of the first base station according to the sequence and a third preset rule, including: The second base station judges the clock synchronization state of the first base station according to the format of the sequence and a third preset rule. 57. The method according to claim 50, wherein the second base station receives the clock synchronization state of the first base station through air interface signaling, comprising: The second base station reads preset bits in the physical broadcast channel PBCH sent by the first base station; The second base station judges the clock synchronization state of the first base station according to preset bits in the PBCH and a fourth preset rule. 58. The method according to claim 50, wherein the second base station receives the clock source synchronization state of the first base station through air interface signaling, comprising: The second base station reads the synchronization level sent by the first base station in the physical layer channel; the second base station judges the clock synchronization of the first base station according to the synchronization level and a fifth preset rule state. 59. The method according to claim 50, wherein the second base station receives the clock synchronization status of the first base station through air interface signaling, comprising: The second base station receives the clock synchronization state of the first base station sent by the UE through an uplink transmission channel, and the information about the clock synchronization state of the first base station is sent to the first base station through a physical layer channel by the first base station. described UE. 60. The method according to claim 50 or 59, wherein the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, and a bearer system information block Channels of the SIB, a paging channel, a physical downlink control channel PDCCH, an enhanced physical downlink control channel EPDCCH, and a physical downlink shared channel PDSCH. 61. A clock synchronization method, comprising: The first base station determines its own clock synchronization state, the clock synchronization state of the first base station includes whether the clock synchronization of the first base station is reliable and/or the type of clock synchronization, and the clock synchronization state of the first base station The type includes at least one of the clock synchronization source of the first base station, the operator to which the first base station belongs, the base station type of the first base station, and the identity of the first base station; The first base station sends the clock synchronization state of the first base station to the second base station, so that the second base station determines the synchronization source base station according to the clock synchronization state of the first base station, and according to the first base station The clock information is synchronized. 62. The method according to claim 61, wherein the first base station sends the clock synchronization state of the first base station to the second base station, comprising: The first base station sends the clock synchronization status of the first base station by way of air interface signaling. 63. The method according to claim 61, wherein the first base station sends a second base station The station sends the clock synchronization state of the first base station, including: The first base station sends the clock synchronization state of the first base station through a backhaul link; or, The first base station reports the clock synchronization state of the first base station to a centralized controller, so that the centralized controller sends the clock synchronization state of the first base station to the second base station; or, The first base station reports the clock synchronization state of the first base station to the macro base station, so that the macro base station sends the clock synchronization state of the first base station to the second base station. 64. The method according to any one of claims 61-63, wherein the first base station sends the clock synchronization state of the first base station to the second base station, comprising: The first base station sends the cell identity of the first base station to the second base station, so that the second base station judges the cell identity of the first base station according to the cell identity of the first base station and a first preset rule Clock synchronization status. 65. The method according to claim 62, wherein the first base station sends the cell identifier of the first base station to the second base station, comprising: The first base station determines the master synchronization sequence according to its own clock synchronization state and the sixth preset rule PSS and\or secondary synchronization sequence or SSS; The first base station sends the primary synchronization sequence PSS and/or the secondary synchronization sequence SSS to the second base station, so that the second base station transmits the primary synchronization sequence PSS and/or the secondary synchronization sequence The step sequence SSS determines the cell identity of the first base station. 66. The method according to claim 62, wherein the first base station sends the clock synchronization status of the first base station through air interface signaling, including: The first base station determines at least one sequence according to its own clock synchronization state and a second preset rule; The first base station sends the sequence through air interface signaling, so that the second base station judges the clock synchronization state of the first base station according to the sequence and the second preset rule. 67. The method according to claim 66, characterized in that, There is a preset time interval between the sending time position of the sequence and the PSS or the SSS sending time position, and/or between the sending frequency position of the sequence and the PSS or the SSS sending frequency position with preset frequency intervals; The first base station sends the sequence through air interface signaling, including: The first base station sends the primary synchronization sequence to the second base station? 88 and\or secondary synchronization sequence SSS, and at least one of said sequences. 68. The method according to claim 66 or 67, wherein the first base station sends the clock synchronization status of the first base station through air interface signaling, including: The first base station determines the format of the sequence according to its own clock synchronization state and a third preset rule; The first base station sends the sequence to the second base station according to the format, so that the second base station judges the clock synchronization state of the first base station according to the format of the sequence. 69. The method according to claim 62, wherein the first base station sends the clock synchronization state of the first base station through air interface signaling, comprising: The first base station carries its own clock synchronization state in the preset bits in the physical broadcast channel PBCH, The first base station sends the physical broadcast channel PBCH to the second base station, so that the second base station judges the physical broadcast channel PBCH according to preset bits in the physical broadcast channel PBCH and a fourth preset rule Clock synchronization status. 70. The method according to claim 62, wherein the first base station sends the clock synchronization state of the first base station through air interface signaling, comprising: The first base station determines the synchronization level of the first base station according to its own clock synchronization state and a fifth preset rule; The first base station sends the synchronization level of the first base station to the second base station on a physical layer channel, so that the second base station judges the synchronization level according to the synchronization level and the fifth preset rule. The clock synchronization state of the first base station. 71. The method according to claim 62, wherein the first base station sends the clock synchronization state of the first base station through air interface signaling, comprising: The first base station sends the clock synchronization state of the first base station to the UE through a physical layer channel, so that the UE sends the clock synchronization state of the first base station to the second base station through an uplink transmission channel. 72. The method according to claim 70 or 71, wherein the physical layer channel includes at least one of the following: a synchronization channel SCH, a physical broadcast channel PBCH, a channel carrying a system information block SIB, a paging channel, a physical Downlink control channel PDCCH, enhanced physical downlink control Channel EPDCCH, physical downlink shared channel PDSCH.