CN104066166B

CN104066166B - A kind of time synchronization method and small base station

Info

Publication number: CN104066166B
Application number: CN201310093045.3A
Authority: CN
Inventors: 张兴炜; 万蕾; 马莎; 李强; 郑娟
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2013-03-21
Filing date: 2013-03-21
Publication date: 2018-03-09
Anticipated expiration: 2033-03-21
Also published as: WO2014146601A1; CN104066166A

Abstract

The embodiment of the present invention discloses a timing synchronization method and a small base station, which are used to avoid the problem that the small base station needs to search for a synchronization source again when a superior synchronization base station cannot be used for timing synchronization. The embodiment of the present invention includes: determining a first upper-level synchronization base station for timing synchronization; determining at least one second upper-level synchronization base station; if the second upper-level synchronization base station is used as a candidate for timing synchronization, when the first upper-level synchronization base station During timing synchronization, the second upper-level synchronization base station is used for timing synchronization; if the second upper-level synchronization base station is also used for timing synchronization, the first upper-level synchronization base station and/or the second upper-level synchronization base station are used for timing synchronization.

Description

Timing synchronization method and small base station

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a timing synchronization method and a small base station.

Background

In Long Term Evolution LTE (Long Term Evolution) -a Rel-12 release, enhancement for hot spot areas is a hot issue. The hot spot area is formed by covering a plurality of low-power Small base stations (Pico eNB, Pico eNodeB) to form a plurality of Small Cell Networks (SCN).

Since the coverage area of the small base station is smaller than that of a Macro base station (MeNB), the number of served User Equipments (UEs) is also smaller than that of the MeNB, and thus, the overhead of pilot and control signaling can be reduced. In addition, because the small base station serves a small number of UEs, there are sometimes even no UEs that need to provide services, and because the small base station functions to improve system throughput, unlike a macro base station that needs to ensure coverage, the small base station may be turned off or put into a sleep state for power saving, and the small base station that is put into the sleep state no longer provides services for the UEs.

In LTE Time Division Duplex (TDD) and LTE Frequency Division Duplex (FDD) systems, precise synchronization between cells is required in order to reduce interference between cells. For scenarios without macro coverage, it is difficult for the small cell to acquire timing synchronization. The most common synchronization method for a Home Evolved NodeB (HeNB) is a Network Listening Mechanism (NLM). In NLM, small base station uses network monitor to obtain synchronization from another base station, and keeps synchronization with the upper synchronous base station, if small base station can not obtain synchronization from another base station, it needs to obtain synchronization from distant base station through multiple nodes; however, in the process of timing synchronization, when the upper synchronization base station cannot be used for timing synchronization, the small base station needs to spend a certain time to search for the synchronization source again, and cannot provide service for the UE during this time, and the base stations using the small base station as the upper synchronization base station cannot perform timing synchronization to obtain a stable synchronization source.

Disclosure of Invention

The embodiment of the invention provides a timing synchronization method and a small base station, which are used for avoiding the problem that the small base station needs to search a synchronization source again when a synchronization base station cannot be used for timing synchronization.

In view of the above, a first aspect of the present invention provides a timing synchronization method, including:

determining a first superior synchronous base station for timing synchronization;

determining at least one second superior synchronous base station;

if the second superior synchronous base station is used for the alternative of timing synchronization, the second superior synchronous base station is utilized to carry out timing synchronization when the first superior synchronous base station cannot be used for timing synchronization;

and if the second superior synchronous base station is also used for timing synchronization, the first superior synchronous base station and/or the second superior synchronous base station are/is used for timing synchronization.

In a first possible implementation manner of the first aspect, if the second superordinate synchronization base station is used as a candidate for timing synchronization, the second superordinate synchronization base station determines based on the following manner:

determining a base station having the same synchronization level as the first superior synchronization base station as a second superior synchronization base station;

or determining the base station with the highest synchronization grade as a second superior synchronization base station;

or determining the base station with the maximum signal strength as a second superior synchronous base station.

With reference to the first possible implementation manner of the first aspect, in a second possible implementation manner, the determining that the base station with the highest synchronization level is a second superior synchronization base station includes:

if the base station with the same synchronization level as the first superior synchronization base station is determined to be absent, determining the base station with the highest synchronization level as a second superior synchronization base station;

the determining that the base station with the maximum signal strength is the second superior synchronous base station includes:

if it is determined that there is no base station having the same synchronization level as the first superior synchronization base station or there are a plurality of base stations having the same synchronization level as the first superior synchronization base station, determining the base station having the largest signal strength as a second superior synchronization base station; or

And if the base station with the same synchronization grade with the first superior synchronization base station is determined to be absent and a plurality of base stations with the highest synchronization grade exist, determining the base station with the maximum signal intensity as a second superior synchronization base station.

With reference to the first possible implementation manner of the first aspect, in a third possible implementation manner, if the second superior synchronization base station is used as an alternative to timing synchronization, the method further includes:

and if the second superior synchronous base station cannot be used for timing synchronization or the second superior synchronous base station is upgraded to the current superior synchronous base station for timing synchronization, determining a new alternative superior synchronous base station based on the determination mode of the second superior synchronous base station.

In a fourth possible implementation manner of the first aspect, if the second superordinate synchronization base station is used as an alternative for timing synchronization, the method further includes:

if the first superior synchronous base station and the second superior synchronous base station have different synchronous grades, and the second superior synchronous base station is upgraded to the superior synchronous base station currently used for timing synchronization, the self synchronous grade is adjusted to be lower than the synchronous grade of the second superior synchronous base station by one grade, and the base station taking the first superior synchronous base station as the superior synchronous base station is controlled to correspondingly adjust the synchronous grade.

With reference to any one of the first to fourth possible implementation manners of the first aspect, in a fifth possible implementation manner, if the second superordinate synchronization base station is used as a candidate for timing synchronization, before the determining at least one second superordinate synchronization base station, the method includes:

setting and maintaining a list of alternative superior synchronous base stations, wherein the alternative superior synchronous base stations in the list of alternative superior synchronous base stations have the same synchronous grade and are the same as the synchronous grade of the first superior synchronous base station, or the alternative superior synchronous base stations in the list of alternative superior synchronous base stations have different synchronous grades;

the determining at least one second superior synchronization base station is:

and determining at least one candidate superior synchronous base station in the candidate superior synchronous base station list as the second superior synchronous base station based on the determination mode of the second superior synchronous base station.

In a sixth possible implementation manner of the first aspect, if the second superordinate synchronization base station is used for timing synchronization, the first superordinate synchronization base station and the second superordinate synchronization base station are determined based on the following manner:

and determining a group of at least two base stations with the same synchronization level as a first superior synchronous base station and a second superior synchronous base station, wherein the error between the first superior synchronous base station and the second superior synchronous base station is within a preset threshold range.

With reference to the sixth possible implementation manner of the first aspect, in a seventh possible implementation manner, if the second superior synchronization base station is used for timing synchronization, the first superior synchronization base station and the second superior synchronization base station are further determined based on the following manner:

if a plurality of groups of base stations with the same synchronization level are determined and the error between the base stations is within a preset threshold range, determining that the group of base stations with the highest synchronization level is a first superior synchronization base station and a second superior synchronization base station;

or if a plurality of groups of base stations with the same synchronization level are determined and the error between the base stations is within the preset threshold range, determining that at least two base stations with the maximum signal intensity are a first superior synchronization base station and a second superior synchronization base station;

or if a plurality of groups of base stations with the same synchronization grade are determined and the error between the base stations is within the preset threshold range, determining that the group of base stations with at least two same superior synchronization base stations are the first superior synchronization base station and the second superior synchronization base station.

With reference to the seventh possible implementation manner of the first aspect, in an eighth possible implementation manner, the determining that the group of base stations with the largest signal strength is the first superior synchronization base station and the second superior synchronization base station includes:

if a plurality of groups of base stations with the same synchronization level are determined, the error between the base stations is within a preset threshold range, and a plurality of groups of base stations with the highest synchronization level exist, determining that at least two base stations with the highest signal intensity are a first superior synchronization base station and a second superior synchronization base station;

the determining that the group of at least two base stations having the same superior synchronization base station are the first superior synchronization base station and the second superior synchronization base station includes:

if a plurality of groups of base stations with the same synchronization level are determined, the error between the base stations is within a preset threshold range, and a plurality of groups of base stations with the highest synchronization level are determined, the group of base stations with at least two same superior synchronization base stations are determined as a first superior synchronization base station and a second superior synchronization base station; or

And if a plurality of groups of base stations with the same synchronization level are determined, the error between the base stations is within the preset threshold range, and a plurality of groups of base stations with the maximum signal intensity are arranged in the base stations with the highest synchronization level, determining that the group of base stations with at least two same superior synchronization base stations are the first superior synchronization base station and the second superior synchronization base station.

With reference to the eighth possible implementation manner of the first aspect, in a ninth possible implementation manner, if the second superior synchronization base station is used for timing synchronization, the method further includes:

acquiring the position of the second superior synchronous base station for sending the synchronous signal;

and setting the MBSFN subframe as a Multimedia Broadcast Single Frequency Network (MBSFN) subframe at a corresponding position of the MBSFN subframe.

With reference to the eighth possible implementation manner of the first aspect, in a tenth possible implementation manner, if the second superior synchronization base station is used for timing synchronization, the method further includes:

acquiring the position of the second superior synchronous base station for receiving the synchronous signal sent by the superior synchronous base station;

and setting the MBSFN subframe at the corresponding position of the MBSFN subframe.

In an eleventh possible implementation manner of the first aspect, the performing timing synchronization by using the second superior synchronization base station includes:

when the link with the first superior synchronous base station fails, judging that the first superior synchronous base station cannot be used for timing synchronization; or,

and when the link between the first superior synchronous base station and the superior synchronous base station fails, judging that the first superior synchronous base station cannot be used for timing synchronization.

In a twelfth possible implementation form of the first aspect, the timing synchronization includes an initial timing synchronization and a synchronization tracking.

A second aspect of the present invention provides a small cell, including:

the device comprises a determining module, a synchronization module and a synchronization module, wherein the determining module is used for determining a first superior synchronization base station for timing synchronization;

the determining module is further configured to determine at least one second superior synchronization base station;

a processing module, configured to perform timing synchronization by using the second superior synchronization base station when the first superior synchronization base station cannot be used for timing synchronization if the second superior synchronization base station is used for a candidate for timing synchronization;

the processing module is further configured to perform timing synchronization by using the first superior synchronization base station and/or the second superior synchronization base station if the second superior synchronization base station is also used for timing synchronization.

In a first possible implementation manner of the second aspect, if the second superordinate synchronization base station is used as a candidate for timing synchronization, the determining module specifically determines the second superordinate synchronization base station based on the following manner: determining a base station having the same synchronization level as the first superior synchronization base station as a second superior synchronization base station; or determining the base station with the highest synchronization grade as a second superior synchronization base station; or determining the base station with the maximum signal strength as a second superior synchronous base station.

With reference to the first possible implementation manner of the second aspect, in a second possible implementation manner, the determining module is configured to determine that the base station with the highest synchronization level is the second superior synchronization base station, specifically, if it is determined that there is no base station with the same synchronization level as the first superior synchronization base station, determine that the base station with the highest synchronization level is the second superior synchronization base station;

the determining module is configured to determine that the base station with the largest signal strength is the second superior synchronization base station, and specifically, if it is determined that there is no base station with the same synchronization level as the first superior synchronization base station or there are multiple base stations with the same synchronization level as the first superior synchronization base station, determine that the base station with the largest signal strength is the second superior synchronization base station; or if the base station with the same synchronization grade with the first superior synchronization base station is determined not to exist and a plurality of base stations with the highest synchronization grade exist, determining the base station with the maximum signal intensity as a second superior synchronization base station.

With reference to the first possible implementation manner of the second aspect, in a third possible implementation manner, if the second superior synchronization base station is used as a candidate for timing synchronization, the determining module is further configured to:

In a fourth possible implementation manner of the second aspect, if the second superordinate synchronization base station is used as a candidate for timing synchronization, the small cell further includes:

the adjusting module is used for adjusting the synchronization level of the first superior synchronization base station to be lower than that of the second superior synchronization base station by one level when the first superior synchronization base station and the second superior synchronization base station have different synchronization levels and the second superior synchronization base station is upgraded to the current superior synchronization base station for timing synchronization;

and the control module is used for controlling the base station taking the small base station as a superior synchronous base station to correspondingly adjust the synchronous grade.

With reference to any one of the first to fourth possible implementation manners of the second aspect, in a fifth possible implementation manner, if the second superior synchronization base station is used as a candidate for timing synchronization, the small cell further includes:

a setting module, configured to set and maintain a list of alternative superior synchronization base stations, where the alternative superior synchronization base stations in the list of alternative superior synchronization base stations have the same synchronization level and are the same as the synchronization level of the first superior synchronization base station, or the alternative superior synchronization base stations in the list of alternative superior synchronization base stations have different synchronization levels;

the determining module is configured to determine that at least one second superordinate synchronization base station is specifically a second superordinate synchronization base station based on a determination manner of the second superordinate synchronization base station, and determine that at least one candidate superordinate synchronization base station in the candidate superordinate synchronization base station list is the second superordinate synchronization base station.

In a sixth possible implementation manner of the second aspect, if the second superordinate synchronization base station is used for timing synchronization, the determining module determines the first superordinate synchronization base station and the second superordinate synchronization base station based on the following manner: and determining a group of at least two base stations with the same synchronization level as the first superior synchronous base station and the second superior synchronous base station, wherein the error between the first superior synchronous base station and the second superior synchronous base station is within a preset threshold range.

With reference to the sixth possible implementation manner of the second aspect, in a seventh possible implementation manner, if the second superior synchronization base station is used for timing synchronization, the determining module further determines the first superior synchronization base station and the second superior synchronization base station based on the following manners: if a plurality of groups of base stations with the same synchronization level are determined and the error between the base stations is within a preset threshold range, determining that the group of base stations with the highest synchronization level is a first superior synchronization base station and a second superior synchronization base station; or if a plurality of groups of base stations with the same synchronization level are determined and the error between the base stations is within the preset threshold range, determining that at least two base stations with the maximum signal intensity are a first superior synchronization base station and a second superior synchronization base station; or if a plurality of groups of base stations with the same synchronization grade are determined and the error between the base stations is within the preset threshold range, determining that the group of base stations with at least two same superior synchronization base stations are the first superior synchronization base station and the second superior synchronization base station.

With reference to the seventh possible implementation manner of the second aspect, in an eighth possible implementation manner, the determining module is configured to determine that the group of base stations with the largest signal strengths is the first superior synchronization base station and the second superior synchronization base station, specifically, if it is determined that there are multiple groups of base stations with the same synchronization level and errors between the multiple groups of base stations are within a preset threshold range and there are multiple groups of base stations with the highest synchronization level, determine that the group of base stations with the largest signal strengths is the first superior synchronization base station and the second superior synchronization base station;

the determining module is configured to determine that the group of base stations with the same upper synchronization base station is a first upper synchronization base station and a second upper synchronization base station, and specifically, if it is determined that there are multiple groups of base stations with the same synchronization level and an error between the multiple groups of base stations is within a preset threshold range and there is a multiple group of base stations with the highest synchronization level, determine that the group of base stations with the same upper synchronization base station is the first upper synchronization base station and the second upper synchronization base station;

or if a plurality of groups of base stations with the same synchronization level are determined, the error between the base stations is within the preset threshold range, and a plurality of groups of base stations with the maximum signal intensity exist in the base stations with the highest synchronization level, the base stations with the same upper synchronization level are determined to be the first upper synchronization base station and the second upper synchronization base station.

With reference to the eighth possible implementation manner of the second aspect, in a ninth possible implementation manner, if the second superior synchronization base station is used for timing synchronization, the small base station further includes:

the acquisition module is used for acquiring the position of the second superior synchronous base station for sending the synchronous signal;

the setting module is used for setting multimedia broadcast single frequency network MBSFN subframes at the corresponding position of the small base station.

With reference to the eighth possible implementation manner of the second aspect, in a tenth possible implementation manner, if the second superior synchronization base station is used for timing synchronization, the small base station further includes:

the acquisition module is used for acquiring the position of the second superior synchronous base station for receiving the synchronous signal sent by the superior synchronous base station;

and the setting module is used for setting the MBSFN subframe at the corresponding position of the small base station.

In an eleventh possible implementation manner of the second aspect, the small cell further includes:

the judging module is used for judging that the first superior synchronous base station cannot be used for timing synchronization when the link with the first superior synchronous base station fails; or, when the link between the first superior synchronization base station and its superior synchronization base station fails, it is determined that the first superior synchronization base station cannot be used for timing synchronization.

It can be seen from the foregoing technical solutions that, in the timing synchronization method and the small base station provided in the embodiments of the present invention, not only the first superior synchronization base station currently used for timing synchronization but also the second superior synchronization base station are determined, and the alternative for timing synchronization or timing synchronization is also determined, so as to avoid the problem that when the current superior synchronization base station cannot be used for timing synchronization, synchronization source search needs to be performed again.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic flowchart of a timing synchronization method according to an embodiment of the present invention;

fig. 2 is another schematic flow chart of a timing synchronization method according to an embodiment of the present invention;

fig. 3 is another schematic flow chart of a timing synchronization method according to an embodiment of the present invention;

fig. 4 is another schematic flow chart of a timing synchronization method according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a small cell provided in an embodiment of the present invention;

fig. 6 is another schematic structural diagram of a small cell base station according to an embodiment of the present invention;

fig. 7 is another schematic structural diagram of a small cell base station according to an embodiment of the present invention.

Detailed Description

The embodiment of the invention provides a timing synchronization method and a small base station, which are used for avoiding the problem that the small base station needs to search a synchronization source again when an upper-level synchronization base station cannot be used for timing synchronization.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The following are detailed below.

Referring to fig. 1, fig. 1 is a schematic flow chart of a timing synchronization method according to an embodiment of the present invention, where the method includes:

s101, determining a first superior synchronous base station for timing synchronization;

the main executing body of the method is a small base station needing timing synchronization, such as a micro base station pico eNB, a home small base station femto eNB, a home base station HeNB and the like, and for convenience of description and understanding, the main executing body can be simply called a target base station; the timing synchronization method can be suitable for a long-term evolution time division duplex (LTE) TDD system and a long-term evolution frequency division duplex (LTE) FDD system;

s102, determining at least one second superior synchronous base station;

it can be understood that the first superior synchronization base station and the second superior synchronization base station are neighboring base stations of the target base station, wherein the first superior synchronization base station is a base station currently used by the target base station for timing synchronization; it is also easy to think that the first superior synchronization Base Station and the second superior synchronization Base Station may be small Base stations, such as pico, femto, HeNB, etc., or may be other types of Base stations, such as Base stations (BS, Base Station, BTS, Base Transceiver Station) in Global System for mobile communications (GSM) or Code Division Multiple Access (CDMA), or may be Base stations (NodeB) in Wideband Code Division Multiple Access (WCDMA), or may be evolved Node BS (eNB or e-NodeB, evolution B) in LTE and LTE-a, which is not specifically limited by the present invention.

In the embodiment of the present invention, the determination order of the first superior synchronization base station and the second superior synchronization base station may be determined according to a specific application scenario, in some embodiments, the first superior synchronization base station may be determined first, and then the second superior synchronization base station may be determined, in some embodiments, the first superior synchronization base station and the second superior synchronization base station may be determined at the same time, which is not limited herein.

S103a, if the second superordinate synchronization base station is used as a candidate for timing synchronization, performing timing synchronization by using the second superordinate synchronization base station when the first superordinate synchronization base station cannot be used for timing synchronization;

in this embodiment, the first upper synchronization base station is a base station currently used by the target base station for timing synchronization, and the second upper synchronization base station is an alternative base station used for timing synchronization when the first upper synchronization base station cannot be used for timing synchronization;

s103b, if the second upper synchronization base station is also used for timing synchronization, performing timing synchronization by the first upper synchronization base station and/or the second upper synchronization base station.

In this embodiment, the first superior synchronization base station and the second superior synchronization base station are both base stations currently used by the target base station for timing synchronization, and the first superior synchronization base station and the second superior synchronization base station may provide timing synchronization for the target base station at the same time or at different times.

As can be seen from the above, the timing synchronization method provided in the embodiment of the present invention determines not only the first superior synchronization base station currently used for timing synchronization, but also the second superior synchronization base station, and is also used for timing synchronization or an alternative for timing synchronization, so as to avoid a problem that the small base station needs to perform synchronization source search again when the current superior synchronization base station cannot be used for timing synchronization.

For convenience of understanding and description, the following embodiments specifically analyze the timing synchronization method provided by the embodiments of the present invention with respect to two cases, that is, an alternative case where the second superior synchronization base station is used for timing synchronization and a case where the second superior synchronization base station is used for timing synchronization, respectively:

if it is assumed that in the embodiment of the present invention, the second superordinate synchronization base station is used as a candidate for timing synchronization, that is, when the target base station searches for a synchronization source, it needs to determine a first superordinate synchronization base station currently used for timing synchronization and determine at least one second superordinate synchronization base station used as a candidate for timing synchronization; referring to fig. 2, fig. 2 is another schematic flow chart of a timing synchronization method according to an embodiment of the present invention, where the method includes:

s201, determining a first superior synchronous base station for timing synchronization;

s202, determining a base station with the same synchronization level as the first superior synchronous base station as a second superior synchronous base station; or determining the base station with the highest synchronization grade as a second superior synchronization base station; or determining the base station with the maximum signal strength as a second superior synchronous base station.

It is understood that the signal strength in the embodiment of the present invention may be a signal strength of a synchronization signal, a reference signal, a control signal, a data signal, or a signal strength superposition of a combination of these signals, which is not limited herein.

Optionally, in this embodiment, the second upper synchronization base station may determine based on the method of S202, or may determine based on the following method:

further, the determining that the base station with the highest synchronization level is the second superior synchronization base station may include:

the determining that the base station with the largest signal strength is the second superior synchronization base station may include:

if it is determined that there is no base station having the same synchronization level as the first superior synchronization base station or there are a plurality of base stations having the same synchronization level as the first superior synchronization base station, determining the base station having the largest signal strength as a second superior synchronization base station; or, if it is determined that there are no base stations having the same synchronization level as the first superior synchronization base station and there are a plurality of base stations having the highest synchronization level, determining the base station having the highest signal strength as the second superior synchronization base station.

It can be understood that, the base stations having the same synchronization level as the first superior synchronization base station are preferentially selected, so that when the first superior synchronization base station cannot be used for timing synchronization, the target base station can directly use the second superior synchronization base station to perform timing synchronization, and the synchronization level of the target base station itself and the synchronization levels of those base stations using the target base station as the superior synchronization base station are not required to be adjusted during timing synchronization;

in some embodiments, the target base station may determine the second superior synchronization base station directly according to the level of the synchronization level; further, in a case where it is determined that there is no base station having the same synchronization level as the first upper synchronization base station, it is preferable to select a base station having the highest synchronization level as the second upper synchronization base station; in addition, it can be understood that the base station with the highest synchronization level can be understood as the base station with the least hop count or the least node forwarding times, and such base station can ensure the smallest accumulation of synchronization precision errors;

in some embodiments, the target base station may determine the second superior synchronization base station directly according to the strength of the signal strength; further, when it is determined that there is no base station having the same synchronization level as the first upper synchronization base station or there are a plurality of base stations having the same synchronization level as the first upper synchronization base station, determining the base station having the largest signal strength as the second upper synchronization base station; or if the base station with the same synchronization grade with the first superior synchronization base station is determined not to exist and a plurality of base stations with the highest synchronization grade exist, determining the base station with the highest signal intensity as the second superior synchronization base station.

S203, when the first superior synchronous base station can not be used for timing synchronization, the second superior synchronous base station is used for timing synchronization;

alternatively, if the target base station determines a first superior synchronization base station for timing synchronization and a second superior synchronization base station for timing synchronization, the alternative superior synchronization base station (i.e. the second superior synchronization base station) may be used based on the following manner:

in an application scenario, if the synchronization level of the second superior synchronization base station is the same as the synchronization level of the first superior synchronization base station, when the first superior synchronization base station cannot be used for timing synchronization, the alternative second superior synchronization base station is upgraded to the current superior synchronization base station, so that the target base station can quickly obtain a new superior synchronization base station. Since the synchronization level of the new upper synchronization base station (i.e., the second upper synchronization base station) is the same as the synchronization level of the original upper synchronization base station (i.e., the first upper synchronization base station), the change of the upper synchronization base station does not cause the change of the synchronization level of the target base station, and the target base station can directly use the new upper synchronization base station (i.e., the second upper synchronization base station) to perform timing synchronization without adjusting its own synchronization level or adjusting the synchronization levels of those base stations using the target base station as the upper synchronization base station.

In another application scenario, if the first superior synchronization base station and the second superior synchronization base station have different synchronization levels and the second superior synchronization base station is upgraded to a superior synchronization base station currently used for timing synchronization, the target base station adjusts its own synchronization level to be one level lower than the synchronization level of the second superior synchronization base station, and controls the base station taking the target base station as the superior synchronization base station to correspondingly adjust the synchronization level.

That is, in the application scenario, when the original upper synchronization base station (i.e., the first upper synchronization base station) cannot be used for timing synchronization, the alternative second upper synchronization base station is also upgraded to the current upper synchronization base station, and the target base station can quickly obtain a new upper synchronization base station. However, since the synchronization level of the new upper synchronization base station (i.e., the second upper synchronization base station) is different from the synchronization level of the original upper synchronization base station (i.e., the first upper synchronization base station), the change of the upper synchronization base station will cause the level of the target base station to change, and at this time, the target base station can directly use the new upper synchronization base station (i.e., the second upper synchronization base station) to perform timing synchronization, but the synchronization level of the target base station itself needs to be adjusted one level lower than the synchronization level of the new upper synchronization base station, and the base stations using the target base station as the upper synchronization base station also need to correspondingly adjust the synchronization levels.

It should be understood that, in this embodiment, the use of the alternative upper synchronization base station (i.e. the second upper synchronization base station) may be applied to a scenario where a plurality of second upper synchronization base stations are provided, and this embodiment only takes one second upper synchronization base station as an example of the alternative upper synchronization base station, and does not limit the present invention.

Optionally, in an alternative implementation manner that the second superior synchronization base station is used for timing synchronization, the timing synchronization method further includes:

It is understood that in this embodiment of the present invention, the target base station always maintains at least one alternative superordinate synchronization base station (i.e. the second superordinate synchronization base station). And when the alternative superior synchronous base station cannot be used for timing synchronization or is upgraded to the superior synchronous base station currently used for timing synchronization, selecting a new alternative superior synchronous base station again according to the selection rule of the alternative superior synchronous base station.

In this embodiment, optionally, before the target base station performs timing synchronization with the second superior synchronization base station (S203), the method may further include: when the link with the first superior synchronous base station fails, judging that the first superior synchronous base station cannot be used for timing synchronization; or, when the link between the first superior synchronization base station and its superior synchronization base station fails, it is determined that the first superior synchronization base station cannot be used for timing synchronization.

It can be understood that, when a link between the target base station and the first upper synchronous base station fails, for example, it is determined that the target base station and the first upper synchronous base station are not synchronized when detecting out-of-synchronization for N consecutive times, where N is a preset value; the link failure between the target base station and the first upper synchronous base station may be caused by the random closing of the first upper synchronous base station, or the poor channel quality between the target base station and the first upper synchronous base station; the link failure of the first superordinate synchronization base station and its superordinate synchronization base station may be caused by the superordinate synchronization base station of the first superordinate synchronization base station being randomly turned off, or the channel quality between the first superordinate synchronization base station and its superordinate synchronization base station being poor, and the like, which is not specifically limited in the present invention.

In addition, in the embodiment of the present invention, the timing Synchronization may include initial timing Synchronization and Synchronization tracking, where the initial timing Synchronization refers to that a target base station or a target terminal initially obtains timing when accessing a network, and at this time, the timing Synchronization needs to be obtained by scanning a Primary/Secondary Synchronization Signal (PSS/SSS); synchronization tracking refers to maintaining synchronization on the basis that timing has been obtained, and fine adjustment of timing is achieved by detecting a Common Reference Signal (CRS) to maintain synchronization.

It can be seen from the foregoing that, in the timing synchronization method provided in the embodiment of the present invention, not only the first superior synchronization base station currently used for timing synchronization is determined, but also the second superior synchronization base station is determined as an alternative for timing synchronization, so as to avoid a problem that the small base station needs to perform synchronization source search again when the current superior synchronization base station cannot be used for timing synchronization, so that the second superior synchronization base station can be used to continue to maintain synchronization, and interference between the base station and the base station, and between the User Equipment (UE) and the UE is reduced.

If it is assumed that in this embodiment of the present invention, the second superordinate synchronization base station is used as an alternative for timing synchronization, which is different from the previous embodiment, in this embodiment, before determining at least one second superordinate synchronization base station, the method further includes setting and maintaining an alternative superordinate synchronization base station list; that is, when a target base station searches for a synchronization source, it needs to determine a first superior synchronization base station currently used for timing synchronization, and also needs to maintain a list of alternative superior synchronization base stations, and it is easy to think that the list of alternative superior synchronization base stations includes a plurality of alternative superior synchronization base stations; referring to fig. 3, fig. 3 is another schematic flow chart of a timing synchronization method according to an embodiment of the present invention, where the method includes:

s301, determining a first superior synchronous base station for timing synchronization;

s302, setting and maintaining a list of alternative superior synchronous base stations;

the synchronization levels of the alternative superior synchronous base stations in the alternative superior synchronous base station list are the same and are the same as the synchronization level of the first superior synchronous base station, or the synchronization levels of the alternative superior synchronous base stations in the alternative superior synchronous base station list are different;

s303, determining at least one alternative superior synchronous base station in the alternative superior synchronous base station list as a second superior synchronous base station;

it can be understood that, in this embodiment, at least one candidate upper synchronization base station in the candidate upper synchronization base station list may be determined to be the second upper synchronization base station based on the determination manner of the second upper synchronization base station in the previous embodiment; that is, in this embodiment, the method of determining the second upper synchronization base station is as follows: determining a base station having the same synchronization level as the first superior synchronization base station as a second superior synchronization base station; or determining the base station with the highest synchronization grade as a second superior synchronization base station; or determining the base station with the maximum signal strength as a second superior synchronous base station.

It is understood that, in this embodiment, no matter in a scenario where the synchronization levels of the alternative upper synchronization base stations in the alternative upper synchronization base station list are the same, or in a scenario where the synchronization levels of the alternative upper synchronization base stations in the alternative upper synchronization base station list are different, when at least one candidate superior synchronous base station is selected and determined as a second superior synchronous base station in the candidate superior synchronous base station list, it is possible to preferentially select a base station having the same synchronization level as the first superior synchronization base station, thus, when the first superior synchronous base station can not be used for timing synchronization, the target base station can directly use the alternative second superior synchronous base station for timing synchronization, when the timing synchronization is carried out, the synchronization grade of the target base station does not need to be adjusted, and the synchronization grade of base stations taking the target base station as a superior synchronization base station does not need to be adjusted;

S304, when the first superior synchronous base station can not be used for timing synchronization, the second superior synchronous base station is used for timing synchronization;

alternatively, if the target base station determines a first superior synchronization base station for timing synchronization and determines an alternative second superior synchronization base station for timing synchronization from the alternative superior synchronization base station list, the second superior synchronization base station may be used based on the following manner:

in an application scenario, when a first superior synchronization base station cannot be used for timing synchronization, a second superior synchronization base station is upgraded to a current superior synchronization base station, so that a target base station can quickly obtain a new superior synchronization base station. If the synchronization level of the second superior synchronization base station is the same as the synchronization level of the first superior synchronization base station, the change of the superior synchronization base station does not cause the synchronization level of the target base station to change, and the target base station can directly use the new superior synchronization base station (i.e., the second superior synchronization base station) to perform timing synchronization without adjusting the synchronization level of the target base station itself or adjusting the synchronization levels of those base stations using the target base station as the superior synchronization base station.

In another application scenario, if the first superior synchronization base station and the second superior synchronization base station have different synchronization levels and the second superior synchronization base station is upgraded to the current superior synchronization base station for timing synchronization, the target base station adjusts its own synchronization level to be one level lower than the synchronization level of the second superior synchronization base station, and controls the base station taking the target base station as the superior synchronization base station to correspondingly adjust the synchronization level.

In this embodiment of the present invention, the determination of the second upper synchronization base station is specifically implemented by taking as an example only the determination method based on the second upper synchronization base station, and selecting at least one candidate upper synchronization base station from the candidate upper synchronization base station list as the second upper synchronization base station, but the present invention is not limited thereto, and in some embodiments, the candidate upper synchronization base stations in the candidate upper synchronization base station list may be arranged in order according to a certain rule, where the rule may refer to the determination method of the second upper synchronization base station, that is, base stations with the same synchronization level as the first upper synchronization base station are arranged in front of base stations with different synchronization levels from the first upper synchronization base station; the base station with small synchronization grade, namely high synchronization grade, is arranged in front of the base station, and the base station with large synchronization grade, namely low synchronization grade, is arranged behind the base station; base stations with large signal strength are arranged in front of the base station, and base stations with small signal strength are arranged behind the base station. If in this embodiment, after the candidate upper synchronization base stations in the candidate upper synchronization base station list are arranged according to the rule, the target base station may determine that at least one candidate upper synchronization base station in the candidate upper synchronization base station list is the second upper synchronization base station; and when the first superior synchronous base station cannot be used for timing synchronization, the second superior synchronous base station is utilized for timing synchronization.

It can be understood that in this embodiment of the present invention, the target base station always maintains a list of alternative upper synchronization base stations. For the optional manner, if the alternative upper synchronization base stations in the alternative upper synchronization base station list are well arranged according to the rule, when the first alternative upper synchronization base station in the alternative upper synchronization base station list is upgraded to the current upper synchronization base station, the second alternative upper synchronization base station in the alternative upper synchronization base station list is upgraded to the first alternative upper synchronization base station in the alternative upper synchronization base station list. It is also easy to think that, in this implementation, when an alternative upper synchronization base station in the alternative upper synchronization base station list cannot be used for timing synchronization, the alternative upper synchronization base station can be removed from the alternative upper synchronization base station list.

In this embodiment, optionally, the target base station performs timing synchronization by using the second superior synchronization base station (S304), and may further include: when the link with the first superior synchronous base station fails, judging that the first superior synchronous base station cannot be used for timing synchronization; or, when the link between the first superior synchronization base station and its superior synchronization base station fails, it is determined that the first superior synchronization base station cannot be used for timing synchronization.

In addition, in the embodiment of the present invention, the timing synchronization may include initial timing synchronization and synchronization tracking, where the initial timing synchronization refers to that a target base station or a target terminal initially obtains timing when accessing a network, and at this time, the initial timing synchronization needs to be obtained by scanning a primary/secondary synchronization signal; synchronization tracking refers to maintaining synchronization on the basis that timing has been obtained, with fine tuning of timing being achieved by detecting a common reference signal to maintain synchronization.

It can be seen from the foregoing that, in the timing synchronization method provided in the embodiment of the present invention, not only the first superior synchronization base station currently used for timing synchronization is determined, but also at least one candidate superior synchronization base station in the candidate superior synchronization base station list is determined as the second superior synchronization base station, which is used as a candidate for timing synchronization, so as to avoid a problem that a small base station needs to perform synchronization source search again when the current superior synchronization base station cannot be used for timing synchronization, so that the second superior synchronization base station can be used to continue to maintain synchronization, and interference between the base station and the base station, and between the UE and the UE is reduced.

If it is assumed that in the embodiment of the present invention, the second superordinate synchronization base station is also used for timing synchronization, that is, when the target base station searches for a synchronization source, it is necessary to determine at least two current superordinate synchronization base stations used for timing synchronization, which are a first superordinate synchronization base station and at least one second superordinate synchronization base station, respectively; referring to fig. 4, fig. 4 is another schematic flow chart of a timing synchronization method according to an embodiment of the present invention, where the method includes:

s401, determining a group of at least two base stations with the same synchronization level as a first superior synchronization base station and a second superior synchronization base station, wherein the error between the base stations is within a preset threshold range.

Optionally, in this embodiment, the first upper synchronization base station and the second upper synchronization base station may be determined based on the method of S401, or may be determined based on the following method:

further, if a plurality of groups of base stations with the same synchronization level are determined and the error between the base stations is within a preset threshold range, determining that the group of base stations with the highest synchronization level is a first superior synchronization base station and a second superior synchronization base station;

Further, the determining that the group of base stations with the largest signal strength is the first superordinate synchronization base station and the second superordinate synchronization base station may include: if a plurality of groups of base stations with the same synchronization level are determined, the error between the base stations is within a preset threshold range, and a plurality of groups of base stations with the highest synchronization level exist, determining that at least two base stations with the highest signal intensity are a first superior synchronization base station and a second superior synchronization base station;

the determining that the group of at least two base stations having the same superordinate synchronization base station are the first superordinate synchronization base station and the second superordinate synchronization base station may include: if a plurality of groups of base stations with the same synchronization level are determined, the error between the base stations is within a preset threshold range, and a plurality of groups of base stations with the highest synchronization level are determined, the group of base stations with at least two same superior synchronization base stations are determined as a first superior synchronization base station and a second superior synchronization base station; or if a plurality of groups of base stations with the same synchronization level are determined, the error between the base stations is within the preset threshold range, and a plurality of groups of base stations with the maximum signal intensity exist in the base stations with the highest synchronization level, the base stations with the same upper synchronization level are determined to be the first upper synchronization base station and the second upper synchronization base station.

It is understood that, in the embodiment of the present invention, the selection and determination of at least two upper synchronization base stations for timing synchronization may refer to the implementation procedure for alternative upper synchronization base stations in the above embodiment, that is, under the condition that it is determined that at least two base stations with the same synchronization level have an error within a preset threshold, the group of base stations with a high synchronization level is preferentially selected, and the group of base stations with a high signal strength is preferentially selected. In this embodiment, if there are a plurality of base stations having the same synchronization level and corresponding signal strengths, the base station having the same upper synchronization base station is preferentially selected.

S402, when the first superior synchronous base station can not be used for timing synchronization, the second superior synchronous base station is used for timing synchronization;

alternatively, if the target base station determines a first superordinate synchronization base station used for timing synchronization and determines a second superordinate synchronization base station also used for timing synchronization, i.e. the target base station determines two superordinate synchronization base stations, the two superordinate synchronization base stations (i.e. the first superordinate synchronization base station and the second superordinate synchronization base station) may be used based on the following ways:

the target base station performs timing synchronization on two superior synchronous base stations at the same time, and receives synchronous signals of the two superior synchronous base stations, at this time, the method may further include: acquiring the position of the second superior synchronous base station for sending the synchronous signal; setting a Multimedia Broadcast Single Frequency Network (MBSFN) subframe at a corresponding position of the target base station, wherein the aim is to realize the synchronization of the target base station; in this embodiment, the method may further include: acquiring the position of the second superior synchronous base station for receiving the synchronous signal sent by the superior synchronous base station; setting MBSFN subframes at the corresponding position of the MBSFN subframe, wherein the purpose is to avoid interference on a second superior synchronous base station; that is to say, the MBSFN subframe of the target base station is the union of the receiving subframes of the two upper synchronous base stations; on the MBSFN subframe, the target base station does not send data, and the UE can also know that the subframe is the MBSFN subframe and does not receive data in the previous configuration information.

It is to be understood that, in this embodiment, the use of two upper synchronization base stations (i.e., a first upper synchronization base station and a second upper synchronization base station) may be applicable to a scenario of multiple upper synchronization base stations, and this embodiment only takes one upper synchronization base station and one second upper synchronization base station as an example of a current upper synchronization base station, and does not limit the present invention.

It should be noted that in this embodiment of the present invention, the target base station always maintains at least two upper synchronization base stations, i.e., a first upper synchronization base station and at least one second upper synchronization base station. When one superior synchronization base station of at least two superior synchronization base stations cannot be used for timing synchronization, the base station no longer serves as the superior synchronization base station. When the number of the upper synchronous base stations of the target base station is less than two, one base station is added according to the selection rule of the upper synchronous base stations, and the newly added base station is required to meet the condition that the synchronization grade is the same as that of the existing upper synchronous base station and the synchronization error is within the preset threshold range.

Optionally, the target base station performs timing synchronization by using the second superior synchronization base station (S402), before the performing, may further include: when the link with the first superior synchronous base station fails, judging that the first superior synchronous base station cannot be used for timing synchronization; or, when the link between the first superior synchronization base station and its superior synchronization base station fails, it is determined that the first superior synchronization base station cannot be used for timing synchronization.

It can be seen from the foregoing that, the timing synchronization method provided in the embodiment of the present invention determines not only the first superior synchronization base station currently used for timing synchronization, but also the second superior synchronization base station, and is also used for timing synchronization, so as to avoid a problem that the small base station needs to perform synchronization source search again when the first superior synchronization base station cannot be used for timing synchronization, so that the second superior synchronization base station can be used to continue to maintain synchronization, and interference between the base station and the base station, and between the UE and the UE is reduced.

In order to better implement the technical solution of the embodiment of the present invention, the embodiment of the present invention further provides a related apparatus for implementing the timing synchronization method. The terms are the same as those in the above timing synchronization method, and details of implementation may refer to the description in the method embodiment.

Referring to fig. 5, fig. 5 is a schematic structural diagram of a small base station 500 according to an embodiment of the present invention, where the small base station 500 may be applied to an LTE TDD system and an LTE FDD system, the small base station 500 may be a micro base station pico eNB, a home small base station femto eNB, a home base station HeNB, and the small base station 500 includes:

a determining module 501, configured to determine a first superior synchronization base station for timing synchronization;

the determining module 501 is further configured to determine at least one second superior synchronization base station;

a processing module 502, configured to, if the second superordinate synchronization base station is used as an alternative for timing synchronization, perform timing synchronization by using the second superordinate synchronization base station when the first superordinate synchronization base station cannot be used for timing synchronization;

in this embodiment, the first upper synchronization base station is a base station currently used for timing synchronization by a small base station (i.e., a target base station) that needs synchronization, and the second upper synchronization base station is an alternative base station used for timing synchronization when the first upper synchronization base station cannot be used for timing synchronization;

the processing module 502 is further configured to perform timing synchronization by using the first superior synchronization base station and/or the second superior synchronization base station if the second superior synchronization base station is also used for timing synchronization.

As can be seen from the above description, the small base station 500 provided in the embodiment of the present invention determines not only the first superior synchronization base station currently used for timing synchronization, but also the second superior synchronization base station, and is also used for timing synchronization or an alternative for timing synchronization, so as to avoid a problem that the small base station needs to perform synchronization source search again when the current superior synchronization base station cannot be used for timing synchronization, so that alternative or other base stations used for timing synchronization can be used to continue to maintain synchronization, and interference between the base station and the base station, and between the UE and the UE can be reduced.

For convenience of understanding and description, the following embodiments respectively analyze the small cell provided by the embodiments of the present invention for two cases, that is, an alternative case where the second superior synchronization base station is used for timing synchronization and a case where the second superior synchronization base station is used for timing synchronization:

if it is assumed that in the embodiment of the present invention, the second superordinate synchronization base station is used as a candidate for timing synchronization, that is, when the target base station searches for a synchronization source, it needs to determine a first superordinate synchronization base station currently used for timing synchronization and determine at least one second superordinate synchronization base station used as a candidate for timing synchronization;

optionally, the determining module 501 determines the second superior synchronization base station specifically based on the following manners: determining a base station having the same synchronization level as the first superior synchronization base station as a second superior synchronization base station; or determining the base station with the highest synchronization grade as a second superior synchronization base station; or determining the base station with the maximum signal strength as a second superior synchronous base station.

Further, the determining module 501 is configured to determine that the base station with the highest synchronization level is the second superior synchronization base station, specifically, if it is determined that there is no base station with the same synchronization level as the first superior synchronization base station, determine that the base station with the highest synchronization level is the second superior synchronization base station;

the determining module 501 is configured to determine that the base station with the largest signal strength is the second superior synchronization base station, and specifically, if it is determined that there is no base station with the same synchronization level as the first superior synchronization base station or there are multiple base stations with the same synchronization level as the first superior synchronization base station, determine that the base station with the largest signal strength is the second superior synchronization base station; or, if it is determined that there are no base stations having the same synchronization level as the first superior synchronization base station and there are a plurality of base stations having the highest synchronization level, determining the base station having the highest signal strength as the second superior synchronization base station.

It can be understood that, the determining module 501 preferentially selects the base stations having the same synchronization level as the first superior synchronization base station, so that when the first superior synchronization base station cannot be used for timing synchronization, the target base station can directly use the second superior synchronization base station to perform timing synchronization, and the synchronization level of the target base station itself does not need to be adjusted during timing synchronization, and the synchronization levels of those base stations using the target base station as the superior synchronization base stations do not need to be adjusted;

In some embodiments, if the second superior synchronization base station is used as an alternative for timing synchronization, when the target base station searches for a synchronization source, it needs to determine a first superior synchronization base station currently used for timing synchronization, and also needs to maintain a list of alternative superior synchronization base stations; referring to fig. 6, fig. 6 is a schematic structural diagram of a small cell 600 in this embodiment, where the small cell includes, in addition to a determining module 501 and a processing module 502, further includes: a setting module 503, configured to set and maintain a list of candidate upper synchronization base stations; the determining module 501 is configured to determine that at least one second superior synchronization base station is specifically a second superior synchronization base station based on a determination manner of the second superior synchronization base station, and determine that at least one candidate superior synchronization base station in the candidate superior synchronization base station list is the second superior synchronization base station. The alternative superior synchronous base stations in the alternative superior synchronous base station list have the same synchronous grade and are the same as the synchronous grade of the first superior synchronous base station, or the alternative superior synchronous base stations in the alternative superior synchronous base station list have different synchronous grades;

optionally, if the second superior synchronization base station is used for alternative timing synchronization, the determining module 501 in this embodiment may be further configured to:

Optionally, if the second superior synchronization base station is used as an alternative for timing synchronization, the small cell 600 may further include: the adjusting module is used for adjusting the synchronization level of the first superior synchronization base station to be lower than that of the second superior synchronization base station by one level when the first superior synchronization base station and the second superior synchronization base station have different synchronization levels and the second superior synchronization base station is upgraded to the current superior synchronization base station for timing synchronization; and the control module is used for controlling the base station taking the small base station as a superior synchronous base station to correspondingly adjust the synchronous grade.

Further optionally, the small cell base station 600 may further include: the judging module is used for judging that the first superior synchronous base station cannot be used for timing synchronization when the link with the first superior synchronous base station fails; or, when the link between the first superior synchronization base station and its superior synchronization base station fails, it is determined that the first superior synchronization base station cannot be used for timing synchronization.

It can be understood that, when a link between the target base station and the first upper synchronous base station fails, for example, it is determined that the target base station and the first upper synchronous base station are not synchronized when detecting out-of-synchronization for N consecutive times, where N is a preset value; the link failure between the target base station and the first upper synchronous base station may be caused by the random closing of the first upper synchronous base station, or the poor channel quality between the target base station and the first upper synchronous base station; the link failure of the first superordinate synchronization base station and its superordinate synchronization base station may be caused by the superordinate synchronization base station of the first superordinate synchronization base station being randomly turned off, or the channel quality between the first superordinate synchronization base station and its superordinate synchronization base station being poor, and the like, which is not specifically limited in the present invention. In addition, in the embodiment of the present invention, the timing synchronization may include initial timing synchronization and synchronization tracking.

As can be seen from the above description, the small cell 600 provided in the embodiment of the present invention determines not only the first superior synchronization base station currently used for timing synchronization, but also determines the second superior synchronization base station as an alternative for timing synchronization, or determines at least one alternative superior synchronization base station in the alternative superior synchronization base station list as the second superior synchronization base station as an alternative for timing synchronization, so as to avoid the problem that the small cell needs to perform synchronization source search again when the current superior synchronization base station cannot be used for timing synchronization, so that the second superior synchronization base station can be used to continue to maintain synchronization, and reduce interference between the base station and the base station, and between the UE and the UE.

If it is assumed that in the embodiment of the present invention, the second superordinate synchronization base station is also used for timing synchronization, that is, when the target base station searches for a synchronization source, it is necessary to determine at least two current superordinate synchronization base stations used for timing synchronization, which are a first superordinate synchronization base station and at least one second superordinate synchronization base station, respectively;

in this embodiment, the determining module 501 may determine the first superior synchronization base station and the second superior synchronization base station based on the following ways: and determining a group of at least two base stations with the same synchronization level as the first superior synchronous base station and the second superior synchronous base station, wherein the error between the first superior synchronous base station and the second superior synchronous base station is within a preset threshold range.

Optionally, the determining module 501 further determines the first superior synchronization base station and the second superior synchronization base station based on the following manners: if a plurality of groups of base stations with the same synchronization level are determined and the error between the base stations is within a preset threshold range, determining that the group of base stations with the highest synchronization level is a first superior synchronization base station and a second superior synchronization base station; or if a plurality of groups of base stations with the same synchronization level are determined and the error between the base stations is within the preset threshold range, determining that at least two base stations with the maximum signal intensity are a first superior synchronization base station and a second superior synchronization base station; or if a plurality of groups of base stations with the same synchronization grade are determined and the error between the base stations is within the preset threshold range, determining that the group of base stations with at least two same superior synchronization base stations are the first superior synchronization base station and the second superior synchronization base station.

Further, the determining module 501 is configured to determine that the group of base stations with the largest signal strengths is the first superior synchronization base station and the second superior synchronization base station, specifically, if it is determined that there are multiple groups of base stations with the same synchronization level and an error between the multiple groups of base stations is within a preset threshold range, and there are multiple groups of base stations with the highest synchronization level, determine that the group of base stations with the largest signal strengths is the first superior synchronization base station and the second superior synchronization base station; the determining module 501 is configured to determine that at least two groups of base stations with the same upper synchronization base station are a first upper synchronization base station and a second upper synchronization base station, and specifically, if it is determined that there are multiple groups of base stations with the same synchronization level and an error between the multiple groups of base stations is within a preset threshold range and there are multiple groups of base stations with the highest synchronization level, determine that at least two groups of base stations with the same upper synchronization base station are the first upper synchronization base station and the second upper synchronization base station; or if a plurality of groups of base stations with the same synchronization level are determined, the error between the base stations is within the preset threshold range, and a plurality of groups of base stations with the maximum signal intensity exist in the base stations with the highest synchronization level, the base stations with the same upper synchronization level are determined to be the first upper synchronization base station and the second upper synchronization base station.

Optionally, if the second superior synchronization base station is used for timing synchronization, the small base station 600 may further include:

the setting module 503 is configured to set an MBSFN subframe of a multimedia broadcast single frequency network at a corresponding position of the small cell.

the setting module 503 is configured to set an MBSFN subframe at a corresponding position of the small cell.

As can be seen from the above description, the small base station 600 provided in the embodiment of the present invention not only determines the first superior synchronization base station currently used for timing synchronization, but also determines the second superior synchronization base station, and is also used for timing synchronization, so as to avoid the problem that the small base station needs to perform synchronization source search again when the first superior synchronization base station cannot be used for timing synchronization, so that the second superior synchronization base station can be used to continue to maintain synchronization, and reduce interference between the base station and the base station, and between the UE and the UE.

It can be clearly understood by those skilled in the art that, for convenience and brevity of description, the specific working processes of the small cell and the unit modules in the small cell described above may refer to the corresponding processes in the foregoing embodiments of the timing synchronization method, and are not described herein again.

Referring to fig. 7, fig. 7 is a schematic structural diagram of another small base station 700 according to an embodiment of the present invention, where the small base station 700 may be applied to an LTE TDD system and an LTE FDD system, the small base station 500 may be a micro base station pico eNB, a home small base station femto eNB, a home base station HeNB, and the like, the small base station 700 includes an input device 701, an output device 702, and a processor 703, where the processor 703 executes the following steps:

determining a first superior synchronous base station for timing synchronization; determining at least one second superior synchronous base station; if the second superior synchronous base station is used for the alternative of timing synchronization, the second superior synchronous base station is utilized to carry out timing synchronization when the first superior synchronous base station cannot be used for timing synchronization; and if the second superior synchronous base station is also used for timing synchronization, the first superior synchronous base station and/or the second superior synchronous base station are/is used for timing synchronization.

In an embodiment, preferably, if the second superordinate synchronization base station is used as an alternative for timing synchronization, the processor 703 may further perform the following steps:

the second superior synchronization base station is determined based on the following manner: determining a base station having the same synchronization level as the first superior synchronization base station as a second superior synchronization base station; or determining the base station with the highest synchronization grade as a second superior synchronization base station; or determining the base station with the maximum signal strength as a second superior synchronous base station.

Preferably, the determining, by the processor 703, that the base station with the highest synchronization level is the second superior synchronization base station specifically includes:

wherein, the determining that the base station with the maximum signal strength is the second superior synchronous base station includes:

Preferably, if the second superior synchronization base station is used for alternative timing synchronization, the processor 703 may further perform the following steps:

Preferably, if the second superordinate synchronization base station is used for the alternative of timing synchronization, before determining at least one second superordinate synchronization base station, the processor 703 may further execute the following steps:

the determining at least one second superior synchronization base station is:

In another embodiment, preferably, if the second superordinate synchronization base station is used for timing synchronization, the processor 703 may further perform the following steps:

the first superior synchronous base station and the second superior synchronous base station are determined based on the following modes: and determining a group of at least two base stations with the same synchronization level as a first superior synchronous base station and a second superior synchronous base station, wherein the error between the first superior synchronous base station and the second superior synchronous base station is within a preset threshold range.

Preferably, if the second superior synchronization base station is used for timing synchronization, the processor 703 may further perform the following steps:

the first superior synchronous base station and the second superior synchronous base station are further determined based on the following modes: if a plurality of groups of base stations with the same synchronization level are determined and the error between the base stations is within a preset threshold range, determining that the group of base stations with the highest synchronization level is a first superior synchronization base station and a second superior synchronization base station;

Preferably, if the second superior synchronization base station is used for timing synchronization, the processor 703 determines that the group of base stations with the largest signal strength is the first superior synchronization base station and the second superior synchronization base station, and specifically includes:

acquiring the position of the second superior synchronous base station for sending the synchronous signal; and setting the MBSFN subframe as a Multimedia Broadcast Single Frequency Network (MBSFN) subframe at a corresponding position of the MBSFN subframe.

acquiring the position of the second superior synchronous base station for receiving the synchronous signal sent by the superior synchronous base station; and setting the MBSFN subframe at the corresponding position of the MBSFN subframe.

Preferably, the processor 703 performs timing synchronization by using the second superior synchronization base station, and may further perform the following steps before performing the timing synchronization:

when the link with the first superior synchronous base station fails, judging that the first superior synchronous base station cannot be used for timing synchronization; or, when the link between the first superior synchronization base station and its superior synchronization base station fails, it is determined that the first superior synchronization base station cannot be used for timing synchronization.

In the embodiment of the invention, the timing synchronization comprises initial timing synchronization and synchronization tracking, wherein the initial timing synchronization means that the target base station or the target terminal obtains timing for the first time when accessing the network, and the timing synchronization needs to be obtained by scanning a main/auxiliary synchronization signal; synchronization tracking refers to maintaining synchronization on the basis that timing has been obtained, with fine tuning of timing being achieved by detecting a common reference signal to maintain synchronization.

As can be seen from the above, in some embodiments, the small cell provided in the embodiment of the present invention determines not only the first superior synchronization base station currently used for timing synchronization, but also determines the second superior synchronization base station to be used as an alternative for timing synchronization; in some embodiments, not only the first superior synchronization base station currently used for timing synchronization is determined, but also at least one candidate superior synchronization base station in the candidate superior synchronization base station list is determined as the second superior synchronization base station for the candidate of timing synchronization; in some embodiments, not only the first superior synchronization base station currently used for timing synchronization but also the second superior synchronization base station is determined and used for timing synchronization, so as to avoid the problem that the small base station needs to perform synchronization source search again when the first superior synchronization base station cannot be used for timing synchronization, thereby being able to use the second superior synchronization base station to continue to maintain synchronization and reduce interference between the base station and the base station, and between the UE and the UE.

It can be clearly understood by those skilled in the art that, for convenience and brevity of description, the specific working process of the small base station described above may refer to the corresponding process in the foregoing timing synchronization method embodiment, and is not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

While the timing synchronization method and the small base station provided by the present invention have been described in detail, those skilled in the art will appreciate that the present invention is not limited thereto, and that the present invention is not limited to the foregoing description.

Claims

1. A timing synchronization method, characterized in that, comprising:

determining a first upper-level synchronization base station for timing synchronization;

determining at least one second superior synchronization base station;

If the second upper-level synchronization base station is used as a candidate for timing synchronization, when the first upper-level synchronization base station cannot be used for timing synchronization, use the second upper-level synchronization base station to perform timing synchronization;

If the second upper-level synchronization base station is also used for timing synchronization, use the first upper-level synchronization base station and/or the second upper-level synchronization base station to perform timing synchronization;

The use of the second superior synchronization base station to perform timing synchronization previously includes:

When the link with the first upper-level synchronization base station fails, it is determined that the first upper-level synchronization base station cannot be used for timing synchronization; or,

When the link between the first upper-level synchronization base station and its upper-level synchronization base station fails, it is determined that the first upper-level synchronization base station cannot be used for timing synchronization;

If the second upper-level synchronization base station is used for timing synchronization, the first upper-level synchronization base station and the second upper-level synchronization base station are determined based on the following method:

Determining at least two groups of base stations with the same synchronization level as the first upper-level synchronization base station and the second upper-level synchronization base station, and the synchronization timing error between them is within a preset threshold range; the same synchronization level refers to the number of synchronization hops same.

2. The method according to claim 1, wherein if the second upper-level synchronization base station is used as a candidate for timing synchronization, the second upper-level synchronization base station is determined based on the following method:

determining that a base station having the same synchronization level as the first upper-level synchronization base station is a second upper-level synchronization base station;

Or determine that the base station with the highest synchronization level is the second superior synchronization base station;

Or determine that the base station with the highest signal strength is the second superior synchronization base station.

3. The method according to claim 2, wherein the determining that the base station with the highest synchronization level is the second superior synchronization base station comprises:

If it is determined that there is no base station with the same synchronization level as the first upper-level synchronization base station, determine that the base station with the highest synchronization level is the second upper-level synchronization base station;

The base station with the largest determined signal strength is the second superior synchronization base station, including:

If it is determined that there is no base station with the same synchronization level as the first upper-level synchronization base station or there are multiple base stations with the same synchronization level as the first upper-level synchronization base station, determine that the base station with the highest signal strength is the second upper-level synchronization base station ;or

If it is determined that there is no base station with the same synchronization level as the first upper level synchronization base station and there are multiple base stations with the highest synchronization level, determine that the base station with the highest signal strength is the second upper level synchronization base station.

4. The method according to claim 2, wherein if the second superior synchronization base station is used as a candidate for timing synchronization, the method further comprises:

If the second upper-level synchronization base station cannot be used for timing synchronization or the second upper-level synchronization base station is upgraded to the current upper-level synchronization base station for timing synchronization, determine a new candidate based on the determination method of the second upper-level synchronization base station Superior synchronization base station.

5. The method according to claim 1, wherein if the second superior synchronization base station is used as a candidate for timing synchronization, the method further comprises:

If the first upper-level synchronous base station and the second upper-level synchronous base station have different synchronization levels, and the second upper-level synchronous base station is upgraded to the current upper-level synchronization base station used for timing synchronization, adjust the self-synchronization level ratio. The synchronization level of the second upper-level synchronization base station is one level lower, and controls the base station using it as the upper-level synchronization base station to adjust the synchronization level accordingly.

6. The method according to any one of claims 2 to 5, wherein if the second upper-level synchronization base station is used as a candidate for timing synchronization, before determining at least one second upper-level synchronization base station, it includes:

Setting and maintaining a list of candidate upper-level synchronization base stations, where the synchronization levels of the candidate upper-level synchronization base stations in the list of candidate upper-level synchronization base stations are all the same, and are the same as the synchronization levels of the first upper-level synchronization base station, or the candidate The synchronization levels of the candidate upper-level synchronization base stations in the selected upper-level synchronization base station list are different;

The determining at least one second upper-level synchronization base station is:

Based on the determining manner of the second upper-level synchronization base station, at least one candidate upper-level synchronization base station in the candidate upper-level synchronization base station list is determined as the second upper-level synchronization base station.

7. The method according to claim 6, wherein if the second upper-level synchronization base station is used for timing synchronization, the first upper-level synchronization base station and the second upper-level synchronization base station are also determined based on the following method:

If it is determined that there are multiple groups of base stations with the same synchronization level and the synchronization timing errors between them are within the preset threshold range, at least two base stations are determined from the group of base stations with the highest synchronization level as the first superior synchronization base station and the second synchronization base station. Two upper-level synchronous base stations;

Or if it is determined that there are multiple groups of base stations with the same synchronization level and the synchronization timing error between them is within the preset threshold range, at least two base stations from the group of base stations with the highest signal strength are determined to be the first superior synchronization a base station and a second superior synchronous base station;

Or if it is determined that there are multiple groups of base stations with the same synchronization level and the synchronization timing error between them is within the preset threshold range, at least two base stations are determined to be the first upper-level synchronization base station from the group of base stations with the same upper-level synchronization base station. The base station and the second superordinate synchronization base station.

8. The method according to claim 7, wherein the determining at least two base stations from the group of base stations with the largest signal strengths as the first upper-level synchronous base station and the second upper-level synchronous base station comprises:

If it is determined that there are multiple groups of base stations with the same synchronization level and the synchronization timing error between them is within the preset threshold range, and there are multiple groups of base stations with the highest synchronization level, determine at least two base stations from the group of base stations with the highest signal strength. The base stations are the first upper level synchronous base station and the second upper level synchronous base station;

The determining at least two base stations from the group of base stations having the same upper-level synchronization base station as the first upper-level synchronization base station and the second upper-level synchronization base station includes:

If it is determined that there are multiple groups of base stations with the same synchronization level and the synchronization timing error between them is within the preset threshold range, and there are multiple groups of base stations with the highest synchronization level, determine from the group of base stations with the same upper level synchronization base station The at least two base stations are a first superordinate synchronization base station and a second superordinate synchronization base station; or

If it is determined that there are multiple groups of base stations with the same synchronization level and the synchronization timing errors between them are within the preset threshold range, and there are multiple groups of base stations with the highest signal strength among the multiple groups of base stations with the highest synchronization level, the base stations with the same The at least two base stations in the group of upper-level synchronization base stations are determined as the first upper-level synchronization base station and the second upper-level synchronization base station.

9. The method according to claim 8, wherein if the second superior synchronization base station is used for timing synchronization, the method further comprises:

Acquiring the location where the second upper-level synchronization base station sends the synchronization signal;

It is set as a multimedia broadcast single frequency network (MBSFN) subframe at its corresponding position.

10. The method according to claim 8, wherein if the second superior synchronization base station is used for timing synchronization, the method further comprises:

Obtaining the location where the second upper-level synchronization base station receives the synchronization signal sent by its upper-level synchronization base station;

It is set as an MBSFN subframe at its corresponding position.

11. The method according to claim 1, wherein the timing synchronization comprises initial timing synchronization and synchronization tracking.

12. A small base station, comprising:

A determining module, configured to determine a first upper-level synchronization base station for timing synchronization;

The determining module is further configured to determine at least one second upper-level synchronization base station;

A processing module, configured to use the second upper-level synchronization base station to perform timing synchronization when the first upper-level synchronization base station cannot be used for timing synchronization if the second upper-level synchronization base station is used as a candidate for timing synchronization;

The processing module is further configured to use the first upper-level synchronization base station and/or the second upper-level synchronization base station to perform timing synchronization if the second upper-level synchronization base station is also used for timing synchronization;

A judging module, configured to determine that the first upper-level synchronization base station cannot be used for timing synchronization when the link with the first upper-level synchronization base station fails; or, when the first upper-level synchronization base station and its upper-level synchronization base station link When it fails, it is determined that the first upper-level synchronization base station cannot be used for timing synchronization;

If the second upper-level synchronization base station is used for timing synchronization, the determination module determines the first upper-level synchronization base station and the second upper-level synchronization base station based on the following method: determining at least two base stations with the same synchronization level as the The first upper-level synchronous base station and the second upper-level synchronous base station, and the mutual synchronization timing error is within a preset threshold range; the same synchronization level means that the number of synchronization hops is the same.

13. The small base station according to claim 12, wherein if the second upper-level synchronization base station is used as a candidate for timing synchronization, the determining module specifically determines the second upper-level synchronization base station based on the following method: determining and The base stations with the same synchronization level as the first upper-level synchronization base station are the second-level synchronization base stations; or the base station with the highest synchronization level is determined to be the second-level synchronization base station; or the base station with the highest signal strength is determined to be the second-level synchronization base station.

14. The small base station according to claim 13, wherein the determining module is configured to determine that the base station with the highest synchronization level is the second upper-level synchronization base station. When synchronizing the base stations of the level, it is determined that the base station with the highest level of synchronization is the second upper-level synchronous base station;

The determining module is configured to determine that the base station with the highest signal strength is the second upper-level synchronization base station, specifically if it is determined that there is no base station with the same synchronization level as the first upper-level synchronization base station or there are multiple base stations that are synchronized with the first-level synchronization base station When the base station has base stations with the same synchronization level, determine that the base station with the highest signal strength is the second superior synchronization base station; or if it is determined that there is no base station with the same synchronization level as the first superior synchronization base station and there are multiple base stations with the highest synchronization level When , it is determined that the base station with the highest signal strength is the second superior synchronization base station.

15. The small base station according to claim 13, wherein if the second superior synchronization base station is used as a candidate for timing synchronization, the determination module is further configured to:

16. The small base station according to claim 12, wherein if the second superior synchronization base station is used as a candidate for timing synchronization, the small base station further comprises:

An adjustment module, configured to adjust if the first upper-level synchronization base station and the second upper-level synchronization base station have different synchronization levels, and the second upper-level synchronization base station is upgraded to the current upper-level synchronization base station used for timing synchronization. The self-synchronization level is one level lower than the synchronization level of the second superior synchronization base station;

A control module, configured to control a base station with the small base station as a superior synchronization base station to correspondingly adjust the synchronization level.

17. The small base station according to any one of claims 13 to 16, wherein if the second superior synchronization base station is used as a candidate for timing synchronization, the small base station further includes:

A setting module, configured to set and maintain a list of candidate upper-level synchronization base stations, where the synchronization levels of the candidate upper-level synchronization base stations in the list of candidate upper-level synchronization base stations are all the same, and are the same as the synchronization levels of the first upper-level synchronization base station, or the synchronization levels of the candidate upper-level synchronization base stations in the candidate upper-level synchronization base station list are different;

The determining module is configured to determine at least one second upper-level synchronous base station, specifically based on the determination method of the second upper-level synchronous base station, and determine at least one candidate upper-level synchronous base station in the list of candidate upper-level synchronous base stations as the second Superior synchronization base station.

18. The small base station according to claim 13, wherein if the second upper-level synchronization base station is used for timing synchronization, the determining module further determines the first upper-level synchronization base station and the second upper-level synchronization base station based on the following method : If it is determined that there are multiple groups of base stations with the same synchronization level and the synchronization timing errors between them are within the preset threshold range, at least two base stations are determined from the group of base stations with the highest synchronization level as the first superior synchronization base station and The second superior synchronization base station; or if it is determined that there are multiple groups of base stations with the same synchronization level and the synchronization timing error between them is within the preset threshold range, at least two base stations are determined from the group of base stations with the highest signal strength as The first upper-level synchronous base station and the second upper-level synchronous base station; or if it is determined that there are multiple groups of base stations with the same synchronization level and the synchronization timing error between them is within the preset threshold range, from the group with the same upper-level synchronous base station The base stations determine at least two base stations as the first upper-level synchronous base station and the second upper-level synchronous base station.

19. The small base station according to claim 18, wherein the determination module is configured to determine at least two base stations from the group of base stations with the highest signal strength as the first upper-level synchronous base station and the second upper-level synchronous base station, specifically: If it is determined that there are multiple groups of base stations with the same synchronization level and the synchronization timing error between them is within the preset threshold range, and there are multiple groups of base stations with the highest synchronization level, determine at least two base stations from the group of base stations with the highest signal strength. The base stations are the first upper level synchronous base station and the second upper level synchronous base station;

The determination module is configured to determine at least two base stations from the group of base stations with the same upper-level synchronization base station as the first upper-level synchronization base station and the second upper-level synchronization base station. Specifically, if multiple groups of base stations with the same synchronization level are determined and When the synchronization timing error between each other is within the preset threshold range, and there are multiple groups of base stations with the highest synchronization level, at least two base stations are determined from the group of base stations with the same upper-level synchronization base station as the first upper-level synchronization base station and the second-level synchronization base station. Superior synchronous base station;

Or if it is determined that there are multiple groups of base stations with the same synchronization level and the mutual errors are within the preset threshold range, and there are multiple groups of base stations with the highest signal strength among the multiple groups of base stations with the highest synchronization level, the The at least two base stations in the group of synchronous base stations are determined as the first upper-level synchronous base station and the second upper-level synchronous base station.

20. The small base station according to claim 17, wherein if the second superior synchronization base station is used for timing synchronization, the small base station further comprises:

An acquisition module, configured to acquire the location where the second superior synchronization base station sends the synchronization signal;

The setting module is configured to set a multimedia broadcast single frequency network (MBSFN) subframe at a corresponding position of the small base station.

21. The small base station according to claim 17, wherein if the second superior synchronization base station is used for timing synchronization, the small base station further comprises:

An acquisition module, configured to acquire the position where the second upper-level synchronization base station receives the synchronization signal sent by its upper-level synchronization base station;

The setting module is configured to set an MBSFN subframe at a corresponding position of the small base station.