CN110519814A - Data transmission method and device, storage medium, base station - Google Patents

Abstract

A kind of data transmission method and device, storage medium, base station, the data transmission method include: the second mapping relations of the data flow and Data Radio Bearer when receiving switching request, before obtaining switching；After signaling is completed in the switching for receiving user equipment transmission, the state report for the data packet transmitted not successfully that user equipment is sent is received；The reception state of the data packet transmitted not successfully is determined according to the first mapping relations of data flow and Data Radio Bearer after switching, second mapping relations and the state report.The Lossless transport of switching evidence may be implemented in technical solution of the present invention.

Description

Data transmission method and device, storage medium, base station

technical field

This application is a divisional application of a patent application with an application date of March 23, 2017, an application number of 201710178216.0, and an invention title of data transmission method, device and user equipment.

The present invention relates to the technical field of communications, in particular to a data transmission method and device, a storage medium, and a base station.

Background technique

In the fifth-generation mobile communication technology (5th-Generation, 5G), in order to realize the separation of the control plane and the user plane, the service data packet will contain the service quality (Quality of Service, QoS) information of the service. For the downlink, after receiving the data packet sent by the core network, the base station adopts an appropriate scheduling policy to schedule transmission resources according to the QoS information contained therein, so as to send the data packet to the user equipment (UE) under the condition of meeting the QoS requirements. ). A UE may initiate multiple services, and each service has a specific QoS, and the QoS of different services may be the same, similar, or completely different. Each service can be called a QoS data flow (Flow). The base station can map different Flows with the same or similar QoS to the same data radio bearer (Data Radio Bearer, DRB) according to its own scheduling algorithm, and QoS Flows with large differences are mapped to different DRBs. In Layer 2 (Layer 2), there is a newly introduced layer dedicated to implementing the mapping from Flow to DRB. This layer is located above the Packet Data Convergence Protocol (PDCP) layer. Layer 2 has four layers in total, respectively It is a newly introduced layer, PDCP layer, radio link control protocol (Radio Link Control, RLC) layer and medium access control (Medium Access Control, MAC) layer.

During handover, the target base station may have different scheduling policies from the source base station. For multiple flows established by the UE, the target base station may map Flow to different DRBs. For example, before the handover, the source base station maps Flow1 and Flow2 to DRB1 , after the handover, the target base station maps Flow1 to DRB1, and maps Flow2 to DRB2. Usually, it is necessary to ensure that the data is complete and not lost during the handover process. For example, for the transmission of downlink data, the source base station will forward the untransmitted data packets to the target base station during the handover process (from the first unconfirmed transmission success The data packet starts to be forwarded, and the DRB is used as the granularity to forward), and the UE can send a PDCP status report (PDCP StatusReport) to the target base station after the handover, so that the target base station can determine which data packets have been correctly received by the UE and which data packets have not yet been received. If it is not received correctly by the UE, the target base station transmits the unconfirmed data packet to the UE. After receiving it, the UE sorts the received data packet, and then sends the data packet to the UE's upper layer in order, so that data lossless switching can be realized.

However, the above method can only be used for scenarios where the data flow mapping does not change during switching. If the data flow mapping changes during handover, for the data flow mapped to the new bearer, the target base station cannot accurately know whether the source base station has any data packets that have not been transmitted to the UE before the handover, which may cause data loss and affect user experience .

Contents of the invention

The technical problem solved by the invention is how to realize lossless transmission of data during switching.

In order to solve the above technical problems, an embodiment of the present invention provides a data transmission method, the data transmission method includes:

When the cell is handed over or after the handover is completed, receive the data stream information to which the unsuccessfully transmitted data packet belongs; according to the data stream information to which the unsuccessfully transmitted data packet belongs and the receiving status of the unsuccessfully transmitted data packet, generate a target for The status report of the data flow is sent to the target base station.

Optionally, the receiving the data stream information to which the unsuccessfully transmitted data packet belongs includes: when receiving the handover command sent by the source base station, receiving the data to which the unsuccessfully transmitted data packet belongs to from the source base station. Flow information, wherein the source base station is a base station before handover, and the target base station is a base station after handover.

Optionally, the data transmission method further includes: when receiving the switching command sent by the source base station, receiving the first mapping relationship between the switched data stream and the data radio bearer together.

Optionally, the receiving the data flow information of the unsuccessfully transmitted data packet includes: after sending the handover completion signaling, receiving the data flow information of the unsuccessfully transmitted data packet sent by the target base station, wherein the source The base station is a base station before handover, and the target base station is a base station after handover.

Optionally, the target base station explicitly indicates the first mapping relationship in the handover request response.

Optionally, the generating a status report for the data flow according to the data flow information to which the unsuccessfully transmitted data packet belongs and the receiving status of the unsuccessfully transmitted data packet, and sending the status report to the target base station includes: according to the Generate a status report for the data flow according to the data flow information to which the unsuccessfully transmitted data packet belongs and the receiving status of the unsuccessfully transmitted data packet; according to the data flow information to which the unsuccessfully transmitted data packet belongs and the first The mapping relationship is to determine the data radio bearer to which the data flow of the unsuccessfully transmitted data packet is mapped after the handover; and send the status report of the data flow mapped to the same data radio bearer to the target base station.

Optionally, after receiving the handover request response sent by the target base station, the source base station forwards the unsuccessfully transmitted data packet to the target base station.

Optionally, the source base station forwards the unsuccessfully transmitted data packets to the target base station; or, the source base station forwards the unsuccessfully transmitted data packets in the same data flow to the target base station. The target base station.

Optionally, after receiving the status report, the target base station determines the unsuccessfully received data packets according to the status report, and sends the unsuccessfully received data packets, and the unsuccessfully received data packets A packet is at least a portion of the unsuccessfully transmitted data packets.

Optionally, the data transmission method further includes: when the sequence numbers of data packets in each data stream are discontinuous, when receiving the unsuccessfully received data packets, according to the data to which the unsuccessfully received data packets belong Flow information and packet sequence numbers adjust the receive window.

Optionally, when the target base station sends the unsuccessfully received data packet or the new data packet, in each data stream, after the successfully received data packet with the largest sequence number, the The data packet after the data packet with the sequence number; or, when the target base station sends the unsuccessfully received data packet or a new data packet, among the unsuccessfully transmitted data packets, the maximum sequence of successfully received After the data packet with the highest sequence number, transmit the data packet after the data packet with the largest sequence number in sequence.

Optionally, when the source base station sends the handover request to the target base station, it explicitly indicates the second mapping relationship between the data flow before the handover and the data radio bearer.

Optionally, the unsuccessfully transmitted data packets include data packets not sent by the source base station and data packets sent by the source base station for which acknowledgment feedback has not been received.

In order to solve the above technical problems, the embodiment of the present invention also discloses a data transmission device, which includes:

The data stream information receiving module is adapted to receive the data stream information to which the unsuccessfully transmitted data packet belongs when the cell is handed over or after the handover is completed; The information and the reception status of the unsuccessfully transmitted data packets generate a status report for the data flow and send it to the target base station.

Optionally, the data flow information receiving module includes: a first data flow information receiving unit, adapted to receive the unsuccessfully transmitted data packet sent by the source base station when receiving the handover command sent by the source base station The data flow information to which it belongs, wherein, the source base station is the base station before the handover, and the target base station is the base station after the handover.

Optionally, the data flow information receiving module further includes: a first receiving unit, adapted to receive the switched data flow and the first Mapping relations.

Optionally, the data flow information receiving module includes: a second data flow information receiving unit, adapted to receive the data flow information sent by the target base station to which the unsuccessfully transmitted data packet belongs after sending the handover completion signaling, Wherein, the source base station is a base station before handover, and the target base station is a base station after handover.

Optionally, when the source base station receives the handover request response sent by the target base station, it also receives the first mapping relationship sent by the target base station.

Optionally, the target base station explicitly indicates the first mapping relationship in the handover request response.

Optionally, the status report sending module includes: a status report generating unit, adapted to generate a report for the data flow according to the data flow information to which the unsuccessfully transmitted data packet belongs and the receiving status of the unsuccessfully transmitted data packet. Status report: the data radio bearer determining unit is adapted to determine the data flow to which the data flow of the unsuccessfully transmitted data packet is mapped after switching according to the data flow information to which the unsuccessfully transmitted data packet belongs and the first mapping relationship The data radio bearer; the status report sending unit is adapted to send the status reports of the data streams mapped to the same data radio bearer to the target base station together.

Optionally, after receiving the handover request response sent by the target base station, the source base station forwards the unsuccessfully transmitted data packet to the target base station.

Optionally, the source base station forwards the unsuccessfully transmitted data packets to the target base station; or, the source base station forwards the unsuccessfully transmitted data packets in the same data flow to the target base station. The target base station.

Optionally, after receiving the status report, the target base station determines the unsuccessfully received data packets according to the status report, and sends the unsuccessfully received data packets, and the unsuccessfully received data packets A packet is at least a portion of the unsuccessfully transmitted data packets.

Optionally, the data transmission device further includes: a receiving window adjustment module, adapted to receive the unsuccessfully received data packets according to the unsuccessful The received data packet belongs to the data flow information and the sequence number of the data packet to adjust the receiving window.

Optionally, when the target base station sends the unsuccessfully received data packet or the new data packet, in each data stream, after the successfully received data packet with the largest sequence number, the The data packet after the data packet with the sequence number; or, when the target base station sends the unsuccessfully received data packet or a new data packet, among the unsuccessfully transmitted data packets, the maximum sequence of successfully received After the data packet with the highest sequence number, transmit the data packet after the data packet with the largest sequence number in sequence.

Optionally, when the source base station sends the handover request to the target base station, it explicitly indicates the second mapping relationship between the data flow before the handover and the data radio bearer.

Optionally, the unsuccessfully transmitted data packets include data packets not sent by the source base station and data packets sent by the source base station for which confirmation feedback has not been received

In order to solve the above technical problem, an embodiment of the present invention further discloses user equipment, where the user equipment includes the data transmission apparatus.

The embodiment of the present invention also discloses a data transmission method, and the data transmission method includes:

When receiving the handover request, obtain the second mapping relationship between the data stream before the handover and the data radio bearer; after receiving the handover completion signaling sent by the user equipment, receive the status report of the unsuccessfully transmitted data packet sent by the user equipment ; Determine the receiving status of the unsuccessfully transmitted data packet according to the first mapping relationship between the switched data flow and the data radio bearer, the second mapping relationship and the status report.

Optionally, the data transmission method further includes: determining an unsuccessfully received data packet according to the receiving status, where the unsuccessfully received data packet is at least a part of the unsuccessfully transmitted data packet; Successfully received data packets are sent to the user equipment.

Compared with the prior art, the technical solutions of the embodiments of the present invention have the following beneficial effects:

The technical solution of the present invention receives the data flow information to which the unsuccessfully transmitted data packet belongs when the cell is handed over or after the handover is completed; according to the data flow information to which the unsuccessfully transmitted data packet belongs and the data flow information of the unsuccessfully transmitted data packet The receive status generates a status report for the data flow and sends it to the target base station. The technical solution of the present invention notifies the user equipment of the data flow information of the data packet that has not been successfully transmitted, so that the user equipment can generate a status report for the data flow and send it to the target base station; thus, the target base station after handover can know The state of the user equipment actually receiving the data packets can accurately send the data packets not received by the user equipment to the user equipment in the subsequent steps, so as to realize the lossless transmission of data during switching, avoid the loss of data packets, and improve the user experience.

Further, when receiving the handover command sent by the source base station, the data flow information to which the unsuccessfully transmitted data packet sent by the source base station is received together, wherein the source base station is the base station before handover, and the target base station is Base station after switching. In the technical solution of the present invention, during the handover process, when receiving the handover command sent by the source base station, the user equipment also receives the data stream information to which the unsuccessfully transmitted data packet belongs, thereby saving signaling overhead.

Further, after the handover completion signaling is sent, the data flow information of the unsuccessfully transmitted data packet sent by the target base station is received, wherein the source base station is the base station before the handover, and the target base station is the base station after the handover. In the technical solution of the present invention, after the handover is completed, the user equipment receives the data flow information of the unsuccessfully transmitted data packet sent by the target base station; through the interaction between the target base station and the user equipment, it is possible to avoid occupying resources of the source base station, Improve the communication efficiency of the base station.

Description of drawings

Fig. 1 is a flowchart of a data transmission method according to an embodiment of the present invention;

FIG. 2 is a flow chart of another data transmission method according to an embodiment of the present invention;

FIG. 3 is a flowchart of another data transmission method according to an embodiment of the present invention;

4 is a schematic structural diagram of a data transmission device according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of another data transmission device according to an embodiment of the present invention.

Detailed ways

As described in the background, the above methods in the prior art can only be used for the scenario where the data flow mapping does not change during switching. If the data flow mapping changes during handover, for the data flow mapped to the new bearer, the target base station cannot accurately know whether the source base station has any data packets that have not been transmitted to the UE before the handover, which may cause data loss and affect user experience .

The technical solution of the present invention notifies the user equipment of the data flow information of the data packet that has not been successfully transmitted, so that the user equipment can generate a status report for the data flow and send it to the target base station; thus, the target base station after handover can know The state of the user equipment actually receiving the data packets can accurately send the data packets not received by the user equipment to the user equipment in the subsequent steps, so as to realize the lossless transmission of data during switching, avoid the loss of data packets, and improve the user experience.

In order to make the above objects, features and advantages of the present invention more comprehensible, specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

FIG. 1 is a flowchart of a data transmission method according to an embodiment of the present invention.

The data transmission method in this embodiment can be applied on the user equipment side.

The data transmission method shown in Figure 1 may include the following steps:

Step S101: when the cell is handed over or after the handover is completed, receive the data flow information to which the unsuccessfully transmitted data packet belongs;

Step S102: Generate a status report for the data flow according to the data flow information to which the unsuccessfully transmitted data packet belongs and the receiving status of the unsuccessfully transmitted data packet, and send it to the target base station.

In a specific implementation, when cell switching occurs, the base station accessed by the user equipment is switched from the source base station to the target base station. In step S101, when the cell is handed over or after the handover is completed, the data stream information to which the unsuccessfully transmitted data packet belongs is received. For example, the PDCP sequence numbers (sequence number, SN) corresponding to the unsuccessfully transmitted data packets are 21, 22, 23 to 40 respectively, wherein, the data flow information to which the data packets with odd sequence numbers belong is Flow1, and the data packets with even sequence numbers The data flow information to which the data packet belongs is Flow2. Then the data flow information of the unsuccessfully transmitted data packets that the user equipment needs to receive may be that the sequence numbers of the unsuccessfully transmitted data packets of Flow1 are 21, 23, 25, 27, 29, 31, 33, 35, 37, 39; The sequence numbers of packets not successfully transmitted by Flow2 are 22, 24, 26, 28, 30, 32, 34, 36, 38, 40.

Those skilled in the art should understand that in actual application scenarios, sequence numbers of data packets in different Flows may be continuous or discontinuous.

Further, the data flow information to which the unsuccessfully transmitted data packet belongs may be sent by the source base station, or may be sent by the target base station. That is, the source base station or the target base station needs to send the sequence number of the data packet in Flow1 and the sequence number of the data packet in Flow2 to the UE.

Further, the unsuccessfully transmitted data packets may include data packets not sent by the source base station and data packets sent by the source base station for which no acknowledgment feedback has been received. Specifically, the unsuccessful transmission refers to the source base station, where the unsuccessfully transmitted data packets may include the data packets that the UE has received but the source base station cannot confirm the successful transmission.

In a specific implementation, in step S102, the user equipment may generate a status report for the data flow according to the data flow information to which the unsuccessfully transmitted data packet belongs and the receiving status of the unsuccessfully transmitted data packet. Specifically, the reception status of the unsuccessfully transmitted data packet may indicate whether the UE has received the data packet. The status report may be a PDCP status report.

For example, for unsuccessfully transmitted data packets with PDCP sequence numbers 21, 22, 23 to 40 respectively, the UE has successfully received data packets with sequence numbers 24, 25, 28, and 29, then the UE can The data flow information and the received data packet information (sequence numbers are 24, 25, 28, 29), respectively generate status reports for Flow1 and Flow2; for Flow1, the sequence numbers are 21, 23, 25, 27, 29 , 31, 33, 35, 37, 39 data packets respectively indicate 0, 0, 1, 0, 1, 0, 0, 0, 0, 0 (0 means not received, 1 means received), come Indicates whether a data packet is received in sequence; similarly, for data packets with sequence numbers 22, 24, 26, 28, 30, 32, 34, 36, 38, 40 in Flow2, indicate 0, 1, 0, 1 respectively , 0, 0, 0, 0, 0, 0, to indicate whether the data packet is received in sequence.

In step S102, the user equipment sends a status report for the data flow to the target base station. The target base station can determine the data packets actually received and not received by the user equipment according to the status report for the data flow, and then resend the unreceived data packets to the user equipment, avoiding the loss of data packets and avoiding The received data packets are sent to the user equipment again to save wireless transmission resources.

It should be noted that the data transmission method in this embodiment can be used in the following scenarios: compared with the data radio bearers mapped by the source base station side, the target base station maps multiple data streams to more data radio bearers, for example, before handover Two data streams are mapped to one data radio bearer, and after switching, the two data streams are mapped to two data radio bearers.

In the embodiment of the present invention, by notifying the user equipment of the data flow information to which the data packet that was not successfully transmitted belongs, the user equipment can generate a status report for the data flow and send it to the target base station; thus, the target base station after handover can know The state of the user equipment actually receiving the data packets can accurately send the data packets not received by the user equipment to the user equipment in the subsequent steps, so as to realize the lossless transmission of data during switching, avoid the loss of data packets, and improve the user experience.

Fig. 2 is a flowchart of another data transmission method according to an embodiment of the present invention. The data transmission method in this embodiment can be applied on the user equipment side.

Those skilled in the art should understand that the process of cell handover may include the following steps: UE sends a measurement report to the source base station, for example, a measurement report indicating that the signal quality of the target cell is higher than a predetermined threshold. After receiving the measurement report, the source base station makes a handover decision and sends a handover request to the target base station. If the target base station allows the UE's access, it returns a handover request response to the source base station after allocating necessary radio parameters. After receiving the handover request response, the source base station sends a handover command to the UE, and the handover command includes radio parameters allocated by the target base station for the UE. The UE accesses the target base station according to the radio parameters in the handover command, and sends a handover completion signaling to the target base station.

The data transmission method shown in Figure 2 may include the following steps:

Step S201: when receiving the handover command sent by the source base station, also receive the data stream information sent by the source base station to which the unsuccessfully transmitted data packet belongs;

Step S202: When receiving the switching command sent by the source base station, receive the first mapping relationship between the switched data stream and the data radio bearer;

Step S203: Generate a status report for the data flow according to the data flow information to which the unsuccessfully transmitted data packet belongs and the receiving status of the unsuccessfully transmitted data packet;

Step S204: According to the data flow information to which the unsuccessfully transmitted data packet belongs and the first mapping relationship, determine the data radio bearer to which the data flow of the unsuccessfully transmitted data packet is mapped after switching;

Step S205: Send the status reports of the data flows mapped to the same data radio bearer to the target base station.

In specific implementation, in step S201, when receiving the handover command sent by the source base station, the user equipment may receive the data flow information sent by the source base station to which the unsuccessfully transmitted data packet belongs, so as to save signaling overhead.

In specific implementation, in step S202, when receiving the handover command sent by the source base station, the user equipment may also receive the first mapping relationship between the handover data flow and the data radio bearer. Specifically, the first mapping relationship may represent a mapping relationship between a data flow and a data radio bearer at the target base station side. That is to say, before step S202, the target base station has sent the first mapping relationship to the source base station, so that the source base station can send the first mapping relationship to the user equipment through a handover command.

Preferably, when the source base station receives the handover request response sent by the target base station, it also receives the first mapping relationship sent by the target base station. In other words, before the source base station sends the handover command to the user equipment, the target base station sends the first mapping relationship to the source base station through a handover request response.

Further, the target base station explicitly indicates the first mapping relationship in the handover request response. That is to say, the source base station can directly obtain the first mapping relationship from the handover request response without other parsing operations, thereby ensuring that the source base station can receive the first mapping relationship accurately and quickly.

Specifically, the radio parameters configured for the UE on the base station side are located in a container of the access layer, and the Xn interface between base stations does not need to understand the radio parameters. If the target base station puts the first mapping relationship into the container, then during the handover process, the source base station needs to analyze the wireless parameters located in the container through the Radio Resource Control (RRC) protocol, and then know whether a Flow to DRB has occurred The mapping changes, so that when the source base station receives the handover request response from the target base station, it will not be able to quickly identify whether there is a Flow-to-DRB mapping change. Further, when the source base station and the target base station belong to different protocol versions, for example, the target base station is a base station of a higher version, and the source base station is a base station of a lower version, at this time, if the target base station configures for the UE that only a base station of a higher version can If the radio parameters are not applicable, the source base station will not be able to identify whether a Flow-to-DRB mapping change has occurred when receiving the handover request response sent by the target base station. Therefore, the target base station may explicitly indicate the switched Flow-to-DRB mapping relationship (that is, the first mapping relationship) in the handover request response.

In a specific implementation, in step S203, the user equipment may generate a status report for the data flow according to the data flow information to which the unsuccessfully transmitted data packet belongs and the receiving status of the unsuccessfully transmitted data packet. Specifically, the user equipment can directly send the status report for the data flow to the target base station.

Further, in step S204, the user equipment may also determine, according to the first mapping relationship, the data radio bearer to which the data flow of the unsuccessfully transmitted data packet is mapped after the handover; and then in step S204, map the same data The status report of the data flow of the radio bearer is also sent to the target base station.

A detailed description will be given below in combination with specific examples. Before the handover, the source base station maps Flow1 and Flow2 to DRB1; after the handover, the target base station maps Flow1 and Flow2 to DRB1 and DRB2 respectively (that is, the first mapping relationship). For the unsuccessfully transmitted data packets whose PDCP sequence numbers are 21, 22, 23 to 40 respectively, the data flow information to which the data packets with odd serial numbers belong is Flow1, and the data flow information to which data packets with even serial numbers belong is Flow2; UE has successfully received data packets with sequence numbers 24, 25, 28, and 29, then the UE can generate status reports for Flow1 and Flow2 as 0, 0, 1, 0, 1, 0, 0, 0 , 0, 0 and 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, to indicate whether the data packet is received in sequence. The UE may send the status reports respectively generated for Flow1 and Flow2 to the target base station.

In another non-limiting embodiment, before the handover, the source base station maps Flow1, Flow2, and Flow3 to DRB1; after the handover, the target base station maps Flow1 and Flow2 to DRB1, and maps Flow3 to DRB2 (that is, the first mapping relationship) . After the UE generates the status reports for Flow1, Flow2 and Flow3, and determines that both Flow1 and Flow2 are mapped to DRB1 according to the first mapping relationship, the UE may combine the status reports for Flow1 and Flow2 and send it to the target base station.

Preferably, after receiving the handover request response sent by the target base station, the source base station forwards the unsuccessfully transmitted data packet to the target base station. Further, the source base station forwards the unsuccessfully transmitted data packets to the target base station together; or, the source base station forwards the unsuccessfully transmitted data packets in the same data flow to the target base station together base station. Specifically, the source base station may also indicate the sequence number corresponding to each data packet to the target base station.

Further, after receiving the status report, the target base station determines the unsuccessfully received data packets according to the status report, and sends the unsuccessfully received data packets, and the unsuccessfully received data packets is at least a part of the unsuccessfully transmitted data packet. For example, after receiving the status report for the data flow, the target base station can determine that among the unsuccessfully transmitted data packets with PDCP sequence numbers 21, 22, 23 to 40, the UE has successfully received the packets with sequence numbers 24, 25 , 28, 29 data packets, other data packets with sequence numbers are not successfully received by UE, that is, data packets with sequence numbers 21, 22, 23, 26, 27, 30 to 40 are not successfully received by UE, then the target base station can send Data packets with other sequence numbers are resent to the UE. Specifically, the target base station may sequentially transmit the data packets not received by the UE starting from the first data packet not received by the UE, that is, start from the data packet with the sequence number 21, and sequentially transmit the data packets with the sequence numbers 21, 22, and 23. , 26, 27, 30 to 40 packets.

Preferably, the data transmission method shown in FIG. 2 may include step S206: when the sequence numbers of data packets in each data stream are discontinuous, when receiving the unsuccessfully received data packets, according to the unsuccessfully received data The data flow information to which the packet belongs and the sequence number of the data packet adjust the receiving window.

Specifically, when the target base station sends the unsuccessfully received data packets, for each data flow, the sequence numbers of the data packets received by the UE may be discontinuous, and at this time, the UE can actively adjust the receiving window to avoid waiting Data packets with certain sequence numbers in this Flow improve communication efficiency. For example, for Flow1, after receiving the data packet with sequence number 27, the UE can know that the data packet with sequence number 28 belongs to Flow2 and the data packet with sequence number 29 has been received according to the data flow information to which the unsuccessfully received data packet belongs. And the next received data packet is the data packet with the sequence number 31, then the receiving window can be adjusted to receive the data packet with the sequence number 31, so as to avoid waiting for the data packet with the sequence number 28 and the data packet with the sequence number 29.

Preferably, when the target base station sends the unsuccessfully received data packet or the new data packet, in each data flow, after the successfully received data packet with the largest sequence number, the maximum sequence number is sequentially transmitted or, when the target base station sends the unsuccessfully received data packet or a new data packet, among the unsuccessfully transmitted data packets, the maximum sequence number successfully received After the data packets, transmit the data packets following the data packet with the largest sequence number in sequence.

Specifically, when the target base station sends an unsuccessfully received data packet, after the UE has received the data packet with the largest sequence number in this Flow (or DRB), it can sequentially transmit the data after the data packet with the largest sequence number Bag. For example, the target base station maps Flow1 and Flow2 to DRB1 and DRB2 respectively; for Flow1, the data packet with the largest sequence number successfully received by the UE is a data packet with sequence number 29, and the target base station encodes the data packet with the original sequence number 31 as 30. The data packet with the original sequence number of 33 is coded as 31 for transmission, and the subsequent data packets are deduced by analogy, that is, the sequential transmission is resumed.

Alternatively, when the target base station sends the unsuccessfully received data packet, it can transmit the data packet with the largest sequence number in order after the data packet with the largest sequence number that the UE has received (that is, the data packet with the largest sequence number in the DRB received by the UE). The data packet after the data packet. For example, if the data packet with the largest sequence number of Flow1 and Flow2 (both mapped to DRB1 of the target base station) in DRB1 successfully received by the UE before handover is a data packet with sequence number 39, then the target base station is sending Flow1 (mapped to DRB1) and Flow2 (Mapped to DRB2) data packets are transmitted sequentially after the data packet with sequence number 39, that is, the data packets after the Flow will be transmitted with the number 40, and the subsequent data packets can be deduced by analogy to recover by sequential transmission.

Fig. 3 is a flowchart of another data transmission method according to an embodiment of the present invention.

The data transmission method shown in Figure 3 may include the following steps:

Step S301: After sending the handover completion signaling, receiving the data flow information of the unsuccessfully transmitted data packet sent by the target base station, wherein the source base station is the base station before the handover, and the target base station is the base station after the handover;

In a specific implementation, the first mapping relationship between the data flow and the data radio bearer after the handover is sent to the UE through the source base station. Specifically, the user equipment may also receive the first mapping relationship when receiving the handover command sent by the source base station.

Step S302: Generate a status report for the data flow according to the data flow information to which the unsuccessfully transmitted data packet belongs and the receiving status of the unsuccessfully transmitted data packet;

Step S303: According to the data flow information to which the unsuccessfully transmitted data packet belongs and the first mapping relationship, determine the data radio bearer to which the data flow of the unsuccessfully transmitted data packet is mapped after the handover;

Step S304: sending the status reports of the data streams mapped to the same data radio bearer to the target base station;

Step S305: When the serial numbers of the data packets in each data stream are discontinuous, when receiving the unsuccessfully received data packets, adjust the reception according to the data stream information and the data packet serial numbers to which the unsuccessfully received data packets belong window.

In specific implementation, in step S301, after accessing the target base station, that is, after sending the handover completion signaling, the user equipment may receive the data flow information sent by the target base station to which the unsuccessfully transmitted data packet belongs. That is, the sequence number of the data packet corresponding to each data flow is sent to the user equipment.

Specifically, after receiving the data flow information to which the unsuccessfully transmitted data packet belongs, the UE sets a status report for the data flow according to the receiving status of the data packet received at the source base station side. A status report for each data flow is then sent to the target base station.

Those skilled in the art should understand that the status report can be set with the PDCP sequence number, so it can be called the PDCP status report, or any other practicable name, which is not limited in the embodiment of the present invention. For example, the newly introduced layer 2 can be merged with PDCP, and the name of the status report can be changed accordingly.

For more details of the specific implementation manners of steps S302 to S305, reference may be made to the relevant descriptions in steps S203 to S206 shown in FIG. 2 , and details will not be repeated here.

Preferably, when the source base station sends the handover request to the target base station, it explicitly indicates the second mapping relationship between the data flow before the handover and the data radio bearer. In other words, before receiving the status report, the target base station has already known the second mapping relationship between the data flow before the handover and the data radio bearer. The source base station may send the second mapping relationship to the target base station through a handover request. Then the target base station can directly obtain the second mapping relationship from the handover request without other parsing operations, thus ensuring that the target base station can accurately receive the second mapping relationship.

Specifically, the radio parameters configured for the UE on the base station side are located in a container of the access layer, and the Xn interface between base stations does not need to understand the radio parameters. If the source base station puts the second mapping relationship into the container, during the handover process, the target base station needs to analyze the wireless parameters in the container through the RRC protocol, and then learn the mapping relationship between Flow and DRB on the source base station side, resulting in the target base station receiving The handover request response cannot quickly identify the mapping relationship between Flow and DRB at the source base station side. Furthermore, when the source base station and the target base station belong to different protocol versions, the target base station may not be able to identify the Flow-to-DRB mapping relationship on the source base station side when receiving the handover request sent by the source base station. Therefore, the source base station may explicitly indicate the mapping relationship between Flow and DRB (that is, the second mapping relationship) in the handover request. That is, the second mapping relationship is not placed in the container of the access layer.

For more working principles and working methods of the embodiments of the present invention, please refer to the related descriptions in FIG. 1 to FIG. 2 , which will not be repeated here.

Fig. 4 is a schematic structural diagram of a data transmission device according to an embodiment of the present invention.

The data transmission apparatus 40 in this embodiment may be used on the user equipment side.

The data transmission device 40 shown in FIG. 4 may include a data flow information receiving module 401 and a status report sending module 402 .

Wherein, the data flow information receiving module 401 is adapted to receive the data flow information to which the unsuccessfully transmitted data packets belong when the cell is handed over or after the handover is completed.

The status report sending module 402 is adapted to generate a status report for the data flow according to the data flow information to which the unsuccessfully transmitted data packet belongs and the receiving status of the unsuccessfully transmitted data packet, and send it to the target base station.

In a specific implementation, the data flow information receiving module 401 receives the data flow information to which the unsuccessfully transmitted data packets belong when the cell is handed over or after the handover is completed. For example, the PDCP sequence numbers (sequence numbers) corresponding to the unsuccessfully transmitted data packets are 21, 22, 23 to 40 respectively. Among them, the data flow information to which the data packets with odd sequence numbers belong is Flow1, and the data packets with even number sequence numbers belong to The data flow information is Flow2.

Further, the data flow information to which the unsuccessfully transmitted data packet belongs may be sent by the source base station, or may be sent by the target base station.

Further, the unsuccessfully transmitted data packets may include data packets not sent by the source base station and data packets sent by the source base station for which no acknowledgment feedback has been received.

In specific implementation, the status report sending module 402 sends the status report for the data flow to the target base station. The target base station can determine the data packets actually received and not received by the user equipment according to the status report for the data flow, and then resend the unreceived data packets to the user equipment, so as to avoid the loss of data packets.

In the embodiment of the present invention, by notifying the user equipment of the data flow information to which the data packet that was not successfully transmitted belongs, the user equipment can generate a status report for the data flow and send it to the target base station; thus, the target base station after handover can know The state of the user equipment actually receiving the data packets can accurately send the data packets not received by the user equipment to the user equipment in the subsequent steps, so as to realize the lossless transmission of data during switching, avoid the loss of data packets, and improve the user experience.

For more details about the working principle and working mode of the data transmission device 40 , reference may be made to the relevant descriptions in FIG. 1 to FIG. 3 , which will not be repeated here.

In order to ensure the lossless transmission of data, the embodiment of the invention also discloses a data transmission method. The data transmission method can be used on the target base station side.

The data transmission method may include the following steps:

When receiving the handover request, obtain the second mapping relationship between the data stream before the handover and the data radio bearer; after receiving the handover completion signaling sent by the user equipment, receive the status report of the unsuccessfully transmitted data packet sent by the user equipment ; Determine the receiving status of the unsuccessfully transmitted data packet according to the first mapping relationship between the switched data flow and the data radio bearer, the second mapping relationship and the status report.

In this embodiment, the target base station can determine the actual receiving status of the user terminal for the unsuccessfully transmitted data packet according to the first mapping relationship, the second mapping relationship and the status report, so that the user terminal can be accurately sent to the user terminal in the subsequent steps. The data packets not received by the device are sent to the user equipment, which avoids the loss of data packets and ensures the lossless transmission of data.

Preferably, the data transmission method further includes: determining the unsuccessfully received data packet according to the receiving status, the unsuccessfully received data packet being at least a part of the unsuccessfully transmitted data packet; The received data packets are sent to the user equipment.

In this embodiment, the UE may set a status report according to the second mapping relationship between the data flow and the data radio bearer before the handover and the receiving status of the unsuccessfully transmitted data packets, and send the status report to the target base station. After the target base station receives the status report, it determines the receiving status of the unsuccessfully transmitted data packet according to the sequence information of the data packet in the data flow. The data packets of 21, 23, 25, 27, 29, and 31 belong to Flow1. At the same time, it is learned that the data packets of sequence numbers 25 and 29 have been successfully received, and the data packets of sequence numbers 21, 23, 27, and 31 have not been successfully received.

In a specific implementation, after receiving the handover request response, the source base station may forward the untransmitted data packets to the target base station. The source base station can forward it to the target base station in a unified manner, or can forward respective unsuccessfully transmitted data packets to the target base station according to the data flow, and at the same time indicate the sequence number corresponding to each data packet to the target base station.

Further, the target base station may notify the user equipment of the sequence number of the data packet in each data stream. That is, the UE is notified that the data packets with sequence numbers 21, 23, 25, 27, 29, and 31 belong to Flow1. The target base station can also notify the UE that the data packets with sequence numbers 25 and 29 have been received successfully; or, the target base station can also notify the UE that the data packets with sequence numbers 21, 23, 27, and 31 have not been successfully received at the same time, so that the UE , can accurately determine the sequence number of the next data packet received by the Flow, avoid unnecessary waiting, improve communication efficiency, and improve user experience.

Optionally, the target base station may also notify the user equipment of the data flow information to which the data packet before the data packet with the largest sequence number received by the user equipment belongs, and after the successfully received data packet with the largest sequence number, transmit the Packets after the packet with the highest sequence number. For example, if the data packet with the largest sequence number received by the UE is the data packet with the sequence number 29, the target base station notifies the UE that the data packets with the sequence numbers 21, 23, 25, 27, and 29 belong to Flow1, and then no matter whether the data packet is on the source base station side What is the sequence number of , and the target base station will number the data packets of Flow1 in sequence according to the sequence numbers 30, 31, and 32.

Furthermore, when the UE receives the handover command, it may also receive the first mapping relationship, and determine according to the first mapping relationship that the mapping between the data flow and the data radio bearer after the handover has changed. A status report is generated for the second mapping relationship between the data flow and the data radio bearer.

It can be understood that the status report may be a PDCP status report.

Fig. 5 is a schematic structural diagram of another data transmission device according to an embodiment of the present invention

The data transmission device 50 shown in FIG. 5 may include a data flow information receiving module 501 , a status report sending module 502 and a receiving window adjusting module 503 .

Specifically, the data flow information receiving module 501 may include a first data flow information receiving unit 5011 and a first receiving unit 5012 . Wherein, the first data flow information receiving unit 5011 is adapted to receive the data flow information sent by the source base station to which the unsuccessfully transmitted data packet belongs when receiving the switching command sent by the source base station, wherein the source The base station is a base station before handover, and the target base station is a base station after handover. The first receiving unit 5012 is adapted to receive the first mapping relationship between the switched data stream and the data radio bearer when receiving the switching command sent by the source base station.

The data flow information receiving module 501 may also include a second data flow information receiving unit 5013 . Wherein, the second data flow information receiving unit 5013 is adapted to receive the data flow information of the unsuccessfully transmitted data packet sent by the target base station after sending the handover completion signaling, wherein the source base station is the base station before the handover, and the The target base station is the base station after handover.

Specifically, the status report sending module 502 may include a status report generating unit 5021 , a data radio bearer determining unit 5022 and a status report sending unit 5023 .

Wherein, the status report generating unit 5021 is adapted to generate a status report for the data flow according to the data flow information to which the unsuccessfully transmitted data packet belongs and the receiving status of the unsuccessfully transmitted data packet; the data radio bearer determining unit 5022 is adapted to Based on the data flow information to which the unsuccessfully transmitted data packet belongs and the first mapping relationship, determine the data radio bearer to which the data flow of the unsuccessfully transmitted data packet is mapped after switching; the status report sending unit 5023 is adapted to and sending the status report of the data flow mapped to the same data radio bearer to the target base station.

In a specific implementation, the receiving window adjustment module 503 is adapted to when receiving the unsuccessfully received data packet when the sequence numbers of the data packets in each data stream are discontinuous, according to the data stream to which the unsuccessfully received data packet belongs Message and packet sequence numbers adjust the receive window.

In the embodiment of the present invention, by notifying the user equipment of the data flow information to which the data packet that was not successfully transmitted belongs, the user equipment can generate a status report for the data flow and send it to the target base station; thus, the target base station after handover can know The state of the user equipment actually receiving the data packets can accurately send the data packets not received by the user equipment to the user equipment in the subsequent steps, so as to realize the lossless transmission of data during switching, avoid the loss of data packets, and improve the user experience.

For more details about the working principle and working mode of the data transmission device 50 , reference may be made to the related descriptions in FIG. 1 to FIG. 4 , which will not be repeated here.

The embodiment of the present invention also discloses a user equipment, where the user equipment includes the data transmission device 40 shown in FIG. 4 or the data transmission device 50 shown in FIG. 5 . The data transmission device 40 or the data transmission device 50 may be internally integrated or externally coupled to the user equipment, and the user equipment may perform data transmission before and after cell handover. The users include but are not limited to mobile phones, tablet computers, and computers.

Those of ordinary skill in the art can understand that all or part of the steps in the various methods of the above-mentioned embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, and the storage medium can include: ROM, RAM, disk or CD, etc.

Although the present invention is disclosed above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, so the protection scope of the present invention should be based on the scope defined in the claims.

Claims (6)

1. a kind of data transmission method characterized by comprising

When receiving switching request, the second mapping relations of data flow and Data Radio Bearer before obtaining switching；

After signaling is completed in the switching for receiving user equipment transmission, the data packet transmitted not successfully that user equipment is sent is received State report；

According to the first mapping relations of data flow and Data Radio Bearer after switching, second mapping relations and the state Report determines the reception state of the data packet transmitted not successfully.

2. data transmission method according to claim 1, which is characterized in that further include:

Determine that the data packet being not successfully received, the data packet being not successfully received are described failed according to the reception state At least part of the data packet of transmission；

The data packet being not successfully received is sent to the user equipment.

3. a kind of data transmission device characterized by comprising

Second mapping relations obtain module, to when receiving switching request, the data flow and data before obtaining switching are wireless Second mapping relations of carrying；

Status report reception module receives user equipment hair after completing signaling in the switching for receiving user equipment transmission The state report for the data packet transmitted not successfully sent；

Reception state determining module, to according to the first mapping relations of data flow and Data Radio Bearer after switching, described Second mapping relations and the state report determine the reception state of the data packet transmitted not successfully.

4. data transmission device according to claim 3, which is characterized in that further include:

Determine that the data packet being not successfully received, the data packet being not successfully received are described failed according to the reception state At least part of the data packet of transmission；

The data packet being not successfully received is sent to the user equipment.

5. a kind of storage medium, is stored thereon with computer instruction, which is characterized in that the right of execution when computer instruction is run Benefit requires the step of 1 or 2 data transmission method.

6. a kind of base station, including memory and processor, the meter that can be run on the processor is stored on the memory Calculation machine instruction, which is characterized in that perform claim requires 1 or 2 data to pass when the processor runs the computer instruction The step of transmission method.