CN116709424A

CN116709424A - Data transmission method, equipment and system for proximity service

Info

Publication number: CN116709424A
Application number: CN202310716118.3A
Authority: CN
Inventors: 邢玮俊; 吴问付
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-04-03
Filing date: 2020-04-03
Publication date: 2023-09-05
Also published as: CN113498113B; WO2021197269A1; CN113498113A

Abstract

The application discloses a data transmission method, equipment and a system for adjacent service, which relate to the technical field of wireless communication and can solve the problem that service data transmission cannot be completed due to mismatching of a quality of service (quality of service, qoS) parameter of a PC5 interface and a QoS parameter of a Uu interface during data transmission. In the scheme provided by the application, the relay User Equipment (UE) obtains the corresponding relation between the first communication link (such as DRB) and the second communication link (such as SLRB) so as to respectively transmit the service data of the first service between the relay UE and the access network equipment through the first communication link and between the remote UE and the relay UE through the second communication link according to the corresponding relation.

Description

Data transmission method, equipment and system for proximity service

The present application is a divisional application, the application number of which is 202010260428.5, the application date of which is month 4 and 3 of 2020, the entire contents of which are incorporated herein by reference.

Technical Field

The embodiment of the application relates to the technical field of wireless communication, in particular to a method, equipment and a system for transmitting proximity-based services (ProSe) data.

Background

With the widespread use of intelligent terminals, proSe communication is increasingly used in order to improve spectrum utilization, system throughput, increase network coverage, and the like. In ProSe communication, a communication link can be directly established between terminals and communicated directly through the communication link without forwarding the communication by the access network device.

As shown in fig. 1, in a ProSe architecture of a fifth Generation mobile communication technology (5 th-Generation, 5G) communication system, if a ProSe communication link of a PC5 interface is established between a terminal 1 and a terminal 2, the terminal 1 may establish a connection and perform communication with a radio access network (radio access network, RAN) and a core network through a Uu interface between the terminal 2 and the RAN. In the above scenario, the terminal 1 may be referred to as a remote user equipment (remote UE), and the terminal 2 may be referred to as a relay user equipment (UE-to-network relay UE).

Wherein ProSe communication needs to be implemented through an air interface protocol stack. The air interface protocol stack is generally divided into three layers: a physical Layer (also referred to as Layer-1, L1 Layer), a data link Layer (also referred to as Layer-2, L2 Layer), and a network Layer (also referred to as Layer-3, L3 Layer). As shown in fig. 2, in the 5G New Radio (NR) communication system, the L2 layer (i.e., the data link layer) may be divided into the following sublayers: a medium access control (medium access control, MAC) layer, a radio link control (radio link control, RLC) layer, a packet data convergence protocol (packet data convergence protocol, PDCP) layer, and a service data adaptation protocol (service data adaptation protocol, SDAP) layer. The MAC layer is used for providing a logic channel for the RLC layer and mapping the logic channel and a physical channel. The RLC layer is configured to provide RLC channels to the PDCP layer and perform mapping of the RLC channels with logical channels. The PDCP layer is used to provide Radio Bearers (RBs) to the SDAP layer and to map RBs with RLC channels. The RB includes a signaling radio bearer (signaling radio bearer, SRB) for the control plane and a data radio bearer (data radio bearer, DBR) for the user plane. The SDAP layer is used for providing specific quality of service flow (quality of service flow, qoS flow) of the data packet and mapping the QoS flow and the RB. Packets transmitted by the same QoS flow are processed using the same QoS parameters and are represented by QoS flow identifiers (QoS flow identifer, QFI). The QoS parameters are used to indicate one or more of the parameters of the type of resources, priority, delay, packet loss rate, or time window size required for the transmission of the data packet.

In conventional NR ProSe communication, as shown in fig. 3, when an application server has a packet to transmit, first, the packet in a protocol data unit (Protocol Data Unit, PDU) is encapsulated once at the NR-SDAP layer of a remote UE. The NR-SDAP layer then will correspond the data packets to the bearers for physical layer transport according to the QoS requirements of the data packets. Since the protocol between NR-SDAP and NR-PDCP is as defined in TS 38.300, which is a communication protocol used by the Uu interface, the NR-SDAP will correspond to a packet to a corresponding Uu QoS parameter according to the QoS requirement of the packet, and issue the packet to the lower layer through the Uu interface. As such, the remote UE may send the data packet to the relay UE over the PC5 link using Uu QoS parameters.

However, for the same data packet, the requirements for the QoS parameters of the PC5 are different from those of the Uu, and therefore, the data packet cannot be transmitted by the conventional data transmission method.

Disclosure of Invention

The application provides a data transmission method, equipment and a system for adjacent service, which can solve the problem that service data transmission cannot be completed due to mismatch between QoS parameters of a PC5 interface and QoS parameters of a Uu interface.

In order to achieve the above purpose, the embodiment of the application adopts the following technical scheme:

In a first aspect, a method for transmitting data in proximity to a service is provided, which is applied to a relay UE, and includes: the relay UE acquires a corresponding relation between a first communication link and a second communication link; the first communication link is used for transmitting data of a first service between the relay UE and the access network equipment; the second communication link is used for transmitting data of the first service between the relay UE and the remote UE; and the relay UE transmits the data of the first service of the remote UE according to the acquired corresponding relation.

According to the technical scheme provided by the first aspect, the relay UE obtains the correspondence between the first communication link (such as DRB) and the second communication link (such as SLRB), so that the service data of the first service can be transmitted between the relay UE and the access network device through the first communication link and between the remote UE and the relay UE through the second communication link according to the correspondence. By the scheme, the problem that service data transmission cannot be completed due to the fact that QoS parameters of a first communication link (such as DRB) and a second communication link (such as SLRB) are not matched in the conventional technology can be solved.

In one possible implementation manner, the acquiring, by the relay UE, a correspondence between the first communication link and the second communication link includes: the relay UE receives identification information of a first communication link and identification information of a second communication link from access network equipment; and the relay UE establishes a corresponding relation between the first communication link and the second communication link according to the received identification information of the first communication link and the received identification information of the second communication link. The scheme supports the determination of a first communication link and a second communication link by the access network equipment, and the relay UE establishes a corresponding relation between the first communication link and the second communication link according to the first communication link and the second communication link determined by the access network equipment.

In one possible implementation manner, the acquiring, by the relay UE, a correspondence between the first communication link and the second communication link includes: the relay UE receives the correspondence relationship from the access network device. The scheme supports that the access network equipment determines a first communication link and a second communication link, and establishes a corresponding relation between the first communication link and the second communication link according to the determined first communication link and second communication link.

In one possible implementation manner, the acquiring, by the relay UE, a correspondence between the first communication link and the second communication link includes: the relay UE receives a first corresponding relation from access network equipment; the first correspondence is between a first communication link and at least two PC5 interface communication links of a remote UE; the relay UE determines a second communication link from the at least two PC5 interface communication links; the relay UE establishes a correspondence between the first communication link and the second communication link. The scheme supports that the access network equipment determines a first communication link and at least two candidate PC5 interface communication links of the remote UE corresponding to the first communication link, and the relay UE further determines a second communication link from the at least two candidate PC5 interface communication links, so that the corresponding relation between the first communication link and the second communication link is established.

In one possible implementation manner, the method further includes: the relay UE receives PC5 quality of service QoS parameters of a first service from access network equipment; the relay UE receives a second corresponding relation from the access network equipment; the second corresponding relation is the corresponding relation between the at least two PC5 interface communication links and the PC5 QoS parameters; the relay UE determining a second communication link from the at least two PC5 interface communication links, including: and the relay UE determines a second communication link from the at least two PC5 interface communication links according to the PC5 QoS parameters of the first service, the first corresponding relation and the second corresponding relation. The scheme supports that the access network equipment determines a first communication link and at least two candidate PC5 interface communication links of a remote UE corresponding to the first communication link, and the relay UE further determines a final second communication link from the at least two candidate PC5 interface communication links according to the PC5 QoS parameters of the first service, the corresponding relation between the first communication link and the at least two PC5 interface communication links of the remote UE and the corresponding relation between the at least two PC5 interface communication links and the PC5 QoS parameters, so that the corresponding relation between the first communication link and the second communication link is established.

In one possible implementation, the PC5 QoS parameters of the first service include one or more of the following parameters: the method comprises the steps of resource type of a PC5 interface, scheduling priority of the PC5 interface, time delay of the PC5 interface, packet loss rate of the PC5 interface, maximum burst flow of the PC5 interface or time window size of the PC5 interface; wherein, the resource types of the PC5 interface include one or more of the following: guaranteed bit rate GBR types, non-guaranteed bit rate Non-GBR types, and latency critical guaranteed bit rate Delay-critical GBR types. The requirements of the service on interface parameters in the application include, but are not limited to, at least one of resource type, scheduling priority, time delay, packet loss rate, maximum burst traffic or time window size.

In one possible implementation manner, the method further includes: the relay UE receives PC5 QoS parameters of the first service; the relay UE acquiring a correspondence between a first communication link and a second communication link includes: the relay UE receives the identification information of the first communication link from the access network equipment; the relay UE determines a second communication link according to the PC5 QoS parameters of the first service; and the relay UE establishes a corresponding relation between the first communication link and the second communication link. The scheme supports that the access network equipment determines a first communication link, and the relay UE determines a second communication link according to the PC5 QoS parameters of the first service, so that the corresponding relation between the first communication link and the second communication link is established.

In one possible implementation manner, the acquiring, by the relay UE, a correspondence between the first communication link and the second communication link includes: the relay UE receives configuration information of a second communication link from the remote UE; the relay UE receives identification information of a first communication link from an access network device; and the relay UE establishes a corresponding relation between the first communication link and the second communication link according to the configuration information of the second communication link and the identification information of the first communication link. The scheme supports that the access network equipment determines a first communication link, the remote UE determines a second communication link, and finally the relay UE establishes a corresponding relation between the first communication link and the second communication link.

In one possible implementation, the first communication link is a data radio bearer DRB, and the second communication link is a side link radio bearer SLRB.

In a second aspect, a method for transmitting data adjacent to a service is provided, and the method is applied to an access network device, and includes: the access network equipment receives Uu QoS requirement information of a first service; the access network equipment determines to transmit the data of the first service through a first communication link between the access network equipment and the relay UE according to Uu QoS requirement information of the first service; the access network equipment determines a second communication link according to the corresponding relation between the first Uu QoS parameter and the first PC5 QoS parameter and Uu QoS requirement information of the first service; the second communication link is used for transmitting data of the first service between the relay UE and the remote UE; the access network equipment sends communication link information to the relay User Equipment (UE), wherein the communication link information is used for representing or establishing a corresponding relation between a first communication link and a second communication link; the first Uu QoS parameter is used for transmitting data of the first service through a Uu interface between the relay UE and the access network device, and the first PC5 QoS parameter is used for transmitting data of the first service through a PC5 interface between the relay UE and the remote UE.

According to the technical scheme provided by the second aspect, the access network device determines a first communication link for transmitting data of the first service between the access network device and the relay UE according to Uu QoS requirement information of the first service, and determines a second communication link for transmitting data of the first service between the remote UE and the relay UE according to the corresponding relation between Uu QoS parameters of the first service and PC5 QoS parameters in combination with Uu QoS requirement information of the first service. By the scheme, the problem that service data transmission cannot be completed due to mismatching of the first communication link (such as DRB) and the second communication link (such as SLRB) in the conventional technology can be solved.

In one possible implementation manner, the communication link information includes a correspondence between a first communication link and a second communication link; alternatively, the communication link information includes identification information of the first communication link and identification information of the second communication link. The scheme supports the determination of a first communication link and a second communication link by the access network equipment, and the relay UE establishes a corresponding relation between the first communication link and the second communication link according to the first communication link and the second communication link determined by the access network equipment. Or determining, by the access network device, the first communication link and the second communication link, and establishing a correspondence between the first communication link and the second communication link according to the determined first communication link and second communication link.

In one possible implementation manner, the method further includes: the access network equipment receives Uu QoS requirement information of the second service; the access network equipment determines to transmit the data of the second service through the first communication link according to the Uu QoS requirement information of the second service; the access network equipment determines a third communication link according to the corresponding relation between the second Uu QoS parameters and the second PC5 QoS parameters and Uu QoS requirement information of the second service; the third communication link is used for transmitting data of a second service between the relay UE and the remote UE; wherein the communication link information includes a first communication link, and a correspondence relationship between the communication link information and at least two PC5 interface communication links of the remote UE, where the at least two PC5 interface communication links include a second communication link and a third communication link; the second Uu QoS parameters are used for transmitting data of the second service through a Uu interface between the relay UE and the access network device, and the second PC5 QoS parameters are used for transmitting data of the second service through a PC5 interface between the relay UE and the remote UE. The scheme supports the determination of a first communication link and two candidate PC5 interface communication links corresponding to different services of remote UE corresponding to the first communication link by access network equipment, and the relay UE further determines a second communication link from the two candidate PC5 interface communication links finally, so that the corresponding relation between the first communication link and the second communication link is established.

In one possible implementation manner, the method further includes: the access network equipment receives Uu QoS requirement information of a third service; the access network equipment determines to transmit the data of the third service through the first communication link according to Uu QoS requirement information of the third service; the access network equipment determines a fourth communication link for transmitting data of a third service between the relay UE and the remote UE according to the corresponding relation between the third Uu QoS parameter and the third PC5 QoS parameter and Uu QoS requirement information of the third service; wherein the at least two PC5 interface communication links further comprise a fourth communication link; the third Uu QoS parameter is used for transmitting data of the third service through a Uu interface between the relay UE and the access network device, and the third PC5 QoS parameter is used for transmitting data of the third service through a PC5 interface between the relay UE and the remote UE. The scheme supports that the access network equipment determines a first communication link and at least two candidate PC5 interface communication links corresponding to different services of remote UE corresponding to the first communication link, and the relay UE further determines a second communication link from the at least two candidate PC5 interface communication links finally, so that the corresponding relation between the first communication link and the second communication link is established.

In one possible implementation manner, the method further includes: the access network equipment receives Uu QoS requirement information of a fourth service of the second remote UE; the access network equipment determines to transmit the data of the fourth service through the first communication link according to Uu QoS requirement information of the fourth service; the access network equipment determines a fifth communication link for transmitting data of a fourth service between the relay UE and the second remote UE according to the corresponding relation between the fourth Uu QoS parameter and the fourth PC5 QoS parameter and Uu QoS requirement information of the fourth service; the access network equipment sends the corresponding relation between the first communication link and the fifth communication link of the second remote UE to the relay UE; the fourth Uu QoS parameter is used for transmitting data of a fourth service through a Uu interface between the relay UE and the access network equipment, and the fourth PC5 QoS parameter is used for transmitting data of the fourth service through a PC5 interface between the relay UE and the second remote UE; the communication link information also includes identification information of the first remote UE and identification information of the second remote UE. The scheme supports two PC5 interface communication links corresponding to different services of different remote UE corresponding to a first communication link and a first communication link to be determined by access network equipment, and a relay UE further determines a second communication link from the two PC5 interface communication links finally, so that the corresponding relation between the first communication link and the second communication link is established.

In one possible implementation manner, the Uu QoS requirement information of the first service includes one or more of the following: the resource type of the Uu interface, the scheduling priority of the Uu interface, the time delay of the Uu interface, the packet loss rate of the Uu interface, the maximum burst flow of the Uu interface or the time window size of the Uu interface; wherein the resource type of Uu interface includes one or more of the following: guaranteed bit rate GBR types, non-guaranteed bit rate Non-GBR types, and latency critical guaranteed bit rate Delay-critical GBR types. The requirements of the service on interface parameters in the application include, but are not limited to, at least one of resource type, scheduling priority, time delay, packet loss rate, maximum burst traffic or time window size.

In a possible implementation manner, the access network device receives Uu QoS requirement information of the first service from the session management function SMF network element through a protocol data unit PDU session.

In one possible implementation manner, the method further includes: the access network device receives the corresponding relation between the first Uu QoS parameters and the first PC5 QoS parameters from the PCF network element. The proposal supports the PCF network element to manage the corresponding relation between the first Uu QoS parameter and the first PC5 QoS parameter.

In a third aspect, there is provided a relay UE comprising: the receiving and transmitting unit is used for acquiring the corresponding relation between the first communication link and the second communication link; the first communication link is used for transmitting data of a first service between the relay UE and the access network equipment; the second communication link is used for transmitting data of the first service between the relay UE and the remote UE; and the processing unit is used for transmitting the data of the first service of the remote UE according to the acquired corresponding relation.

According to the technical scheme provided by the third aspect, the relay UE obtains the correspondence between the first communication link (such as DRB) and the second communication link (such as SLRB), so that the service data of the first service can be transmitted between the relay UE and the access network device, and between the remote UE and the relay UE according to the correspondence. By the scheme, the problem that service data transmission cannot be completed due to mismatching of the first communication link (such as DRB) and the second communication link (such as SLRB) in the conventional technology can be solved.

In a possible implementation manner, the transceiver unit is further configured to receive, from the access network device, identification information of the first communication link and identification information of the second communication link; the processing unit obtains a correspondence between a first communication link and a second communication link, including: and the processing unit establishes a corresponding relation between the first communication link and the second communication link according to the identification information of the first communication link and the identification information of the second communication link received by the receiving and transmitting unit. The scheme supports the determination of a first communication link and a second communication link by the access network equipment, and the relay UE establishes a corresponding relation between the first communication link and the second communication link according to the first communication link and the second communication link determined by the access network equipment.

In one possible implementation manner, the obtaining, by the processing unit, a correspondence between the first communication link and the second communication link includes: the processing unit receives the corresponding relation from the access network equipment through the receiving and transmitting unit. The scheme supports that the access network equipment determines a first communication link and a second communication link, and establishes a corresponding relation between the first communication link and the second communication link according to the determined first communication link and second communication link.

In a possible implementation manner, the transceiver unit is further configured to receive a first correspondence from an access network device; the first correspondence is between a first communication link and at least two PC5 interface communication links of a remote UE; the processing unit obtains a correspondence between a first communication link and a second communication link, including: the processing unit determines a second communication link from the at least two PC5 interface communication links; and the processing unit establishes a correspondence between the first communication link and the second communication link. The scheme supports that the access network equipment determines a first communication link and at least two candidate PC5 interface communication links of the remote UE corresponding to the first communication link, and the relay UE further determines a second communication link from the at least two candidate PC5 interface communication links, so that the corresponding relation between the first communication link and the second communication link is established.

In a possible implementation manner, the transceiver unit is further configured to receive a PC5 quality of service QoS parameter of the first service from the access network device; receiving a second correspondence from the access network device; the second corresponding relation is the corresponding relation between the at least two PC5 interface communication links and the PC5 QoS parameters; the processing unit determines a second communication link from the at least two PC5 interface communication links, including: and the processing unit determines a second communication link from the at least two PC5 interface communication links according to the PC5 QoS parameters of the first service, the first corresponding relation and the second corresponding relation. The scheme supports that the access network equipment determines a first communication link and at least two candidate PC5 interface communication links of a remote UE corresponding to the first communication link, and the relay UE further determines a final second communication link from the at least two candidate PC5 interface communication links according to the PC5 QoS parameters of the first service, the corresponding relation between the first communication link and the at least two PC5 interface communication links of the remote UE and the corresponding relation between the at least two PC5 interface communication links and the PC5 QoS parameters, so that the corresponding relation between the first communication link and the second communication link is established.

In a possible implementation manner, the transceiver unit is further configured to receive a PC5 QoS parameter of the first service; and receiving identification information of the first communication link from an access network device; the processing unit obtains a correspondence between a first communication link and a second communication link, including: the processing unit determines a second communication link according to the PC5 QoS parameters of the first service; and the processing unit establishes a corresponding relation between the first communication link and the second communication link. The scheme supports that the access network equipment determines a first communication link, and the relay UE determines a second communication link according to the PC5 QoS parameters of the first service, so that the corresponding relation between the first communication link and the second communication link is established.

In a possible implementation manner, the transceiver unit is further configured to receive configuration information of the second communication link from the remote UE; receiving identification information of a first communication link from an access network device; the processing unit obtains a correspondence between a first communication link and a second communication link, including: and the processing unit establishes a corresponding relation between the first communication link and the second communication link according to the configuration information of the second communication link and the identification information of the first communication link. The scheme supports that the access network equipment determines a first communication link, the remote UE determines a second communication link, and finally the relay UE establishes a corresponding relation between the first communication link and the second communication link.

In a fourth aspect, an access network device is provided, the access network device comprising: a receiving and transmitting unit, configured to receive Uu QoS requirement information of a first service; a processing unit, configured to determine, according to Uu QoS requirement information of the first service, data for transmitting the first service through a first communication link between the access network device and the relay UE; determining a second communication link according to the corresponding relation between the first Uu QoS parameters and the first PC5 QoS parameters and Uu QoS requirement information of the first service; the second communication link is used for transmitting data of the first service between the relay UE and the remote UE; the transceiver unit is further configured to send communication link information to the relay user equipment UE, where the communication link information is used to characterize or establish a correspondence between the first communication link and the second communication link; the first Uu QoS parameter is used for transmitting data of the first service through a Uu interface between the relay UE and the access network device, and the first PC5 QoS parameter is used for transmitting data of the first service through a PC5 interface between the relay UE and the remote UE.

According to the technical solution provided in the fourth aspect, the access network device determines a first communication link for transmitting data of the first service between the access network device and the relay UE according to Uu QoS requirement information of the first service, and determines a second communication link for transmitting data of the first service between the remote UE and the relay UE according to a correspondence between Uu QoS parameters of the first service and PC5 QoS parameters in combination with Uu QoS requirement information of the first service. By the scheme, the problem that service data transmission cannot be completed due to mismatching of the first communication link (such as DRB) and the second communication link (such as SLRB) in the conventional technology can be solved.

In a possible implementation manner, the transceiver unit is further configured to receive Uu QoS requirement information of the second service; the processing unit is further configured to determine, according to Uu QoS requirement information of the second service, to transmit data of the second service through the first communication link; and determining a third communication link according to the corresponding relation between the second Uu QoS parameters and the second PC5 QoS parameters and Uu QoS requirement information of the second service; the third communication link is used for transmitting data of a second service between the relay UE and the remote UE; wherein the communication link information includes a first communication link, and a correspondence relationship between the communication link information and at least two PC5 interface communication links of the remote UE, where the at least two PC5 interface communication links include a second communication link and a third communication link; the second Uu QoS parameters are used for transmitting data of the second service through a Uu interface between the relay UE and the access network device, and the second PC5 QoS parameters are used for transmitting data of the second service through a PC5 interface between the relay UE and the remote UE. The scheme supports the determination of a first communication link and two candidate PC5 interface communication links corresponding to different services of remote UE corresponding to the first communication link by access network equipment, and the relay UE further determines a second communication link from the two candidate PC5 interface communication links finally, so that the corresponding relation between the first communication link and the second communication link is established.

In one possible implementation manner, the transceiver unit is further configured to receive Uu QoS requirement information of the third service; the processing unit is further configured to determine, according to Uu QoS requirement information of the third service, to transmit data of the third service through the first communication link; and determining a fourth communication link for transmitting data of a third service between the relay UE and the remote UE according to the corresponding relation between the third Uu QoS parameter and the third PC5 QoS parameter and Uu QoS requirement information of the third service; wherein the at least two PC5 interface communication links further comprise a fourth communication link; the third Uu QoS parameter is used for transmitting data of the third service through a Uu interface between the relay UE and the access network device, and the third PC5 QoS parameter is used for transmitting data of the third service through a PC5 interface between the relay UE and the remote UE. The scheme supports that the access network equipment determines a first communication link and at least two candidate PC5 interface communication links corresponding to different services of remote UE corresponding to the first communication link, and the relay UE further determines a second communication link from the at least two candidate PC5 interface communication links finally, so that the corresponding relation between the first communication link and the second communication link is established.

In a possible implementation manner, the transceiver unit is further configured to receive Uu QoS requirement information of a fourth service of the second remote UE; the processing unit is further configured to determine, according to Uu QoS requirement information of the fourth service, to transmit data of the fourth service through the first communication link; and determining a fifth communication link for transmitting data of a fourth service between the relay UE and the second remote UE according to the corresponding relation between the fourth Uu QoS parameter and the fourth PC5 QoS parameter and Uu QoS requirement information of the fourth service; the access network equipment sends the corresponding relation between the first communication link and the fifth communication link of the second remote UE to the relay UE; the fourth Uu QoS parameter is used for transmitting data of a fourth service through a Uu interface between the relay UE and the access network equipment, and the fourth PC5 QoS parameter is used for transmitting data of the fourth service through a PC5 interface between the relay UE and the second remote UE; the communication link information also includes identification information of the first remote UE and identification information of the second remote UE. The scheme supports two PC5 interface communication links corresponding to different services of different remote UE corresponding to a first communication link and a first communication link to be determined by access network equipment, and a relay UE further determines a second communication link from the two PC5 interface communication links finally, so that the corresponding relation between the first communication link and the second communication link is established.

In a possible implementation manner, the transceiver unit is further configured to receive Uu QoS requirement information of the first service from the session management function SMF network element through a protocol data unit PDU session.

In a possible implementation manner, the transceiver unit is further configured to receive a correspondence between the first Uu QoS parameter and the first PC5 QoS parameter from the PCF network element. The proposal supports the PCF network element to manage the corresponding relation between the first Uu QoS parameter and the first PC5 QoS parameter.

In a fifth aspect, there is provided a relay UE including: a memory for storing a computer program; a processor for executing the above-mentioned computer program to implement the method for data transmission of proximity services in any of the possible implementations of the first aspect.

In a sixth aspect, an access network device is provided, the access network device comprising: a memory for storing a computer program; a processor for executing the above-mentioned computer program to implement the method for data transmission of proximity services in any of the possible implementations of the second aspect.

A seventh aspect provides a communication system comprising a relay UE as in any of the possible implementations of the third or fifth aspects; and an access network device as in any one of the possible implementations of the fourth or sixth aspect.

In one possible implementation, the communication system further includes one or more of: PCF network elements, remote UE, SMF network elements, or AMF network elements.

In an eighth aspect, a computer readable storage medium is provided, on which computer program code is stored, which computer program code, when being executed by a processor, implements a method for data transmission of proximity services as in any of the possible implementations of the first or second aspect.

In a ninth aspect, a chip system is provided, the chip system comprising a processor, a memory, the memory having computer program code stored therein; the computer program code, when executed by the processor, implements a method of data transmission for proximity services as in any of the possible implementations of the first or second aspect. The chip system may be formed of a chip or may include a chip and other discrete devices.

In a tenth aspect, a computer program product is provided which, when run on a computer, causes a method of data transmission of a proximity service as in any of the possible implementations of the first or second aspects to be implemented.

Drawings

Fig. 1 is an exemplary diagram of ProSe architecture for a 5G communication system;

FIG. 2 is a schematic diagram of a data link layer data processing;

fig. 3 is a diagram of a user plane protocol stack structure of a relay UE data link layer;

FIG. 4 is a diagram of a communication network architecture;

fig. 5 is a schematic hardware structure diagram of a remote UE or a relay UE according to an embodiment of the present application;

fig. 6 is a schematic hardware structure of a network device according to an embodiment of the present application;

fig. 7 is a flowchart of a method for transmitting data of proximity services according to an embodiment of the present application;

Fig. 8 is an interaction diagram of a data transmission method of proximity services according to an embodiment of the present application;

fig. 9 is a second interaction diagram of a data transmission method of proximity services according to an embodiment of the present application;

fig. 10 is an interaction diagram of a data transmission method of proximity services according to an embodiment of the present application;

fig. 11 is an interaction diagram of a data transmission method of proximity services according to an embodiment of the present application;

fig. 12 is an interaction diagram of a data transmission method of proximity services according to an embodiment of the present application;

fig. 13 is an interaction diagram of a data transmission method of proximity services according to an embodiment of the present application;

fig. 14 is a block diagram of a UE according to an embodiment of the present application;

fig. 15 is a block diagram of a network device according to an embodiment of the present application.

Detailed Description

The technical scheme of the application will be described below with reference to the accompanying drawings.

Embodiments of the present application may be applicable to, but not limited to, the following communication systems: narrowband internet of things (NB-IoT) systems, wireless local area network (wireless local access network, WLAN) systems, long term evolution (long term evolution, LTE) systems, fifth generation mobile communication (5th generation mobile networks or 5th generation wireless systems,5G) also referred to as New Radio (NR) systems, or 5G-later communication systems, such as 6G systems, device-to-device (D2D) communication systems, internet of vehicles, etc.

Fig. 4 shows a communication network architecture diagram. Fig. 4 illustrates an interaction relationship between network functions and entities and corresponding interfaces, taking a network service architecture of a 5G system as an example, where the network architecture is a service-based network architecture (service-based architecture, SBA).

As shown in fig. 4, the network functions and entities included in the 5G system mainly include: UE, access Network (AN) or radio access network (radio access network, RAN), user plane function (user plane function, UPF), data Network (DN), access and mobility management function (access and mobility management function, AMF), session management function (session management function, SMF), authentication service function (authentication server function, AUSF), policy control function (policy control function, PCF), application function (application function, AF), network slice selection function (network slice selection function, NSSF), unified data management (unified data management, UDM), network opening function (network exposure function, NEF) and network storage function (network repository function, NRF).

It should be noted that when a UE connects to a network through a relay device, the UE may be referred to as a "remote UE". The relay device is a device that can provide access to a cellular network for a remote UE, and may be a relay station or a UE, where the UE must support PC5 interface communication when the UE acts as a relay device for the remote UE, and the relay device may be referred to as a "relay UE" that indicates that the relay device is located within a coverage area of a mobile network, for example, the relay device may normally access an access network of a 5G system.

As shown in fig. 4, the remote UE is connected to the access network device and the core network device through the relay UE. The interface between the remote UE and the relay UE is a PC5 interface, the interface between the relay UE and the AN/RAN is a Uu interface, the interface point between the remote UE/relay UE and the AMF is AN N1 interface, the interface between the AN/RAN and the AMF is AN N2 interface, the interface between the AN/RAN and the UPF is AN N3 interface, the interface between the SMF and the UPF is AN N4 interface, and the interface between the UPF and the DN is AN N6 interface; namf is a service-based interface presented by AMF, nsm is a service-based interface presented by SMF, nausf is a service-based interface presented by AUSF, NNssf is a service-based interface presented by NSSF, NNef is a service-based interface presented by NEF, NNrf is a service-based interface presented by NRF, npcf is a service-based interface presented by PCF, nudm is a service-based interface presented by UDM, and Naf is a service-based interface presented by AF.

The main functions of each network element are specifically described below.

AN/RAN: the AN/RAN may be constituted by AN/RAN equipment. The AN/RAN device may be a base station of various forms, such as: macro base station, micro base station (also referred to as "small station"), distributed unit-control unit (DU-CU), etc., where DU-CU is a device deployed in a radio access network that is capable of wireless communication with UEs. In addition, the base station may be a wireless controller in a cloud wireless access network (cloud radio access network, CRAN) scenario, or a relay station, an access point, an in-vehicle device, a wearable device, or a network device in a future evolved public land mobile network (public land mobile network, PLMN) network, etc. The AN/RAN device may also be a broadband network service gateway (broadband network gateway, BNG), AN aggregation switch, a non-3 GPP access device, etc. The AN/RAN equipment is mainly responsible for radio resource management, uplink and downlink data classification, quality of service (quality of service, qoS) management, data compression and encryption, signaling processing with a control plane network element or data forwarding with a user plane functional network element and other functions. The embodiment of the application does not limit the specific form and structure of the AN/RAN equipment.

For example, in systems employing different radio access technologies, the names of base station capable devices may vary. For example, the base station may be an evolved universal terrestrial radio access network (evolved universal terrestrial radio access network, E-UTRAN) device in LTE, such as an evolved node B (eNB or E-NodeB), or a next generation radio access network (next generation radio access network, NG-RAN) device in a 5G system, such as a gNB, or the like.

AMF: is mainly responsible for the handling of control plane messages, such as: access control, mobility management, lawful interception, access authentication/authorization, etc. Functions such as AMF include: 1) Processing the access network control surface; 2) Processing the NAS message and taking charge of NAS encryption and integrity protection; 3) Registration management; 4) Connection management; 5) Access management; 6) Mobility management; 7) Intercepting legal information; 8) Providing a session management message between the UE and the SMF; 9) Implementing transparent transmission for routed session management (session management, SM) messages, similar to transparent management; 10 Access authentication; 11 Access grant; 12 Forwarding an SMS message (short message) between the UE and the short message service function SMSF; 13 Interacting with AUSF and UE to obtain an intermediate key for UE authentication; 14 A specific key of the access network is calculated.

SMF: the method is mainly used for session management, network interconnection protocol (internet protocol, IP) address allocation and management of the UE, selection of a manageable user plane function, policy control and charging function interface termination points, downlink data notification and the like. For example, the functions of SMF include: 1) Session management, session establishment, modification and release, including maintenance of the channel between the UPF and AN node; 2) UE IP address allocation and management; 3) Selecting and controlling a user plane function; 4) Configuring a correct service route on the UPF; 5) Performing the landing of the strategy control function; 6) A policy enforcement and QoS control section; 7) Legal interception; 8) A session management section that processes the NAS message; 9) Downlink data indication; 10 Initiating specific session management information (routed through AMF) for the access network; 11 Determining a mode of continuity with the service in the session; 12 A roaming function.

PCF: the method is mainly used for respectively providing UE policy rules, AMF or SMF, accessing management (access management, AM) policy rules and parameters related to SM policy rules for UE, managing user subscription information, interfacing UDM to access subscription user information related to policy decision, and the like. The PCF generally makes policy decisions based on subscription information, etc.

AF: the method is used for providing services and mainly used for: 1) Application impact on traffic routing; 2) Accessing network capability exposure; 3) And interacting with the policy framework to conduct policy management and control.

In addition, for the description of UPF, DN, AUSF, NSSF, NEF, NRF and UDM functions and the like, reference may be made to explanation and explanation in the conventional art, and a detailed description is omitted here.

Remote UE/relay UE: may be desktop, laptop, handheld, wearable, smart home, computing, vehicle-mounted, etc. devices with wireless connectivity. For example, netbooks, tablet computers, smartwatches, ultra Mobile Personal Computers (UMPC), smart cameras, netbooks, personal digital assistants (personal digital assistant, PDA), portable multimedia players (portable multimedia player, PMP), (Augmented Reality, AR)/Virtual Reality (VR) devices, wireless devices on board aircraft, wireless devices on robots, wireless devices in industrial control, wireless devices in telemedicine, wireless devices in smart grids, wireless devices in smart cities (smart cities), wireless devices in smart home (smart home), etc. Or the remote UE/relay UE may also be a wireless device in Narrowband (NB) technology, etc.

In addition, the remote UE/relay UE may also refer to an access terminal, subscriber unit, subscriber station, mobile station, relay station, remote terminal, mobile device, user terminal (user terminal), terminal (terminal), wireless communication device, user agent, or user equipment. The terminal device may also be a cellular telephone, a cordless telephone, a session initiation protocol (session initiation protocol, SIP) phone, a wireless local loop (wireless local loop, WLL) station, a personal digital assistant (personal digital assistant, PDA), a handheld device with wireless communication capabilities, a computing device or other processing device connected to a wireless modem, an in-vehicle device, a wearable device, a terminal device in a future 5G network or a terminal device in a future evolved PLMN or a terminal device in a future car network, etc.

In addition, the remote UE/relay UE may also be a terminal device in an IoT system, where IoT is an important component of future information technology development, and the main technical feature is to connect the article with a network through a communication technology, so as to implement man-machine interconnection and an intelligent network for the interconnection of the article. The IOT technology can achieve mass connection, deep coverage and terminal power saving through, for example, NB technology. The present application is not limited to the specific type and structure of the remote UE/relay UE, etc.

Referring to fig. 5, fig. 5 shows a schematic hardware structure of a UE, which may be a relay UE or a remote UE. As shown in fig. 5, the UE may specifically include: processor 501, radio frequency circuitry 502, memory 503, touch screen 504, bluetooth device 505, one or more sensors 506, wi-Fi device 507, positioning device 508, audio circuitry 509, peripheral interface 510, power supply device 511, fingerprint acquisition device 512, speaker 513, and microphone 514. The components may communicate via one or more communication buses or signal lines (not shown in fig. 5). Those skilled in the art will appreciate that the hardware structure shown in fig. 5 does not constitute a limitation on the relay UE or the remote UE, and that either the relay UE or the remote UE may include more or less components than illustrated, or may combine certain components, or may be arranged in different components.

The following describes the various components of the relay UE in detail with reference to fig. 5:

the processor 501 may be a control center of the relay UE, and performs various functions of the relay UE by running or executing a computer program stored in the memory 503, for example, an application client program (hereinafter may be abbreviated as App) using various interfaces and lines to connect other various parts of the relay UE.

In some embodiments, processor 501 may be a general purpose CPU, microprocessor, special ASIC, or one or more integrated circuits for controlling the execution of the present inventive arrangements, and processor 501 may include one or more CPUs; for example, the processor 501 may be a kylin chip.

The radio frequency circuitry 502 may be used for the reception and transmission of wireless signals. Specifically, the radio frequency circuit 502 may receive downlink data of the base station, and send the downlink data to the processor 501 for processing; in addition, the radio frequency circuit 502 may also send uplink data to the base station.

In general, the radio frequency circuitry 502 includes, but is not limited to, an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, and the like. In addition, the radio frequency circuitry 502 may also communicate with other devices via wireless communications. The wireless communication may use any communication standard or protocol including, but not limited to, global system for mobile communications, general packet radio service, code division multiple access, wideband code division multiple access, long term evolution, email, short message service, and the like.

The memory 503 is used for storing computer programs and may also be used for storing data. The memory 503 may be a read-only memory (ROM) or random-access memory (random access memory, RAM), or an electrically erasable programmable read-only memory (electrically erasable programmable read-only memory, EEPROM), a compact disk (compact disc read-only memory, CD-ROM) or other optical disk storage, optical disk storage (including compact disk, laser disk, optical disk, digital versatile disk, blu-ray disk, etc.), magnetic disk storage media or other magnetic storage device, or any other medium that can be used to carry or store program code and that can be accessed by a computer, but is not limited thereto.

The processor 501 may perform various functions of the relay UE and data processing by executing a computer program stored in the memory 503.

The memory 503 may include a stored program area and a stored data area. Wherein the storage program area may store an operating system, at least one application program required for a function (such as a sound playing function, an image playing function, etc.); the storage data area may store data (such as audio data, phonebook, etc.) created according to when the relay UE is used.

The memory 503 may store a computer program for implementing a modular function, and is controlled to be executed by the processor 501. The processor 501 is configured to execute a computer program stored in the memory 503, thereby implementing the method provided by the following embodiments of the present application.

In addition, memory 503 may include high speed random access memory, and may also include non-volatile memory, such as magnetic disk storage devices, flash memory devices, or other volatile solid state storage devices, and the like. The memory 503 may store various operating systems, such as iOS operating systems, android (Android) operating systems, and the like.

The relay UE may also include at least one or more sensors 506, such as light sensors, motion sensors, and other sensors. Specifically, the light sensor may include an ambient light sensor that may adjust the brightness of the display of the touch screen 504 according to the brightness of ambient light, and a proximity sensor that may turn off the power of the display when the relay UE moves to the ear. As one of the motion sensors, the accelerometer sensor can detect the acceleration in all directions (generally three axes), and can detect the gravity and direction when stationary, and can be used for identifying the application of the gesture of the smart phone (such as horizontal and vertical screen switching, related games, magnetometer gesture calibration), vibration identification related functions (such as pedometer and knocking), and the like; other sensors such as gyroscopes, barometers, hygrometers, thermometers, infrared sensors, etc. that may be configured by the relay UE are not described herein.

Audio circuitry 509, speaker 513, microphone 514 may provide an audio interface between the user and the relay UE. The audio circuit 509 may transmit the received electrical signal converted from audio data to the speaker 513, and the electrical signal is converted into a sound signal by the speaker 513 to be output; on the other hand, microphone 514 converts the collected sound signals into electrical signals, which are received by audio circuitry 509 and converted into audio data, which are output to radio frequency circuitry 502 for transmission to, for example, another UE, or to memory 503 for further processing.

Although not shown in fig. 5, the relay UE may further include a camera (front camera and/or rear camera), a flash, a micro-projection device, a near-field communication (NFC) device, etc., which will not be described herein.

It should be understood that the above hardware modules included in the relay UE shown in fig. 5 are only described by way of example, and are not limiting on the present application. In fact, the remote UE and the relay UE provided in the embodiments of the present application may further include other hardware modules having an interaction relationship with the hardware modules illustrated in the figures, which are not limited in detail herein.

It should be noted that the AN/RAN device in the present application may be a base station. For example, the base station may be an Ng-eNB, a gNB, or a transmission/reception point (TRP). But also a base station as defined by 3 GPP. Such as an eNB or e-NodeB, etc.

Furthermore, when an eNB accesses the core network of NR or the next generation core network (next genaeration core, NGC) or the 5G core network (5th generation core network,5GC), the eNB may also be referred to as an lte eNB. Specifically, the eLTE eNB is an evolved LTE base station device based on the eNB, and can be directly connected with 5G CN, and the eLTE eNB also belongs to the base station device in NR.

Alternatively, the AN/RAN device may also be a wireless endpoint (wireless terminal, WT). Such as an Access Point (AP) or access controller (access controller, AC), or other network device with communication capabilities with the UE, as well as the core network. For example, a relay device, an in-vehicle device, a smart wearable device, etc. The application is not limited to the type of AN/RAN equipment.

Referring to fig. 6, fig. 6 shows a schematic hardware structure of a network device. The network device 600 may be AN/RAN device in the radio access network shown in fig. 1 or fig. 3, or AN/RAN device in the AN/RAN shown in fig. 4, or a core network element such as AN AMF, SMF, or PCF shown in fig. 4. As shown in fig. 6, the network device 600 may include a processor 601, a communication line 602, a memory 603, and at least one communication interface (illustrated in fig. 6 by way of example only as including a communication interface 604).

The processor 601 may include one or more processors, where the processor may be, without limitation, a CPU, microprocessor, specific ASIC, or other integrated circuit.

Communication line 602 may include a pathway for communicating information between the aforementioned components.

Communication interface 604 for communicating with other devices or communication networks.

The memory 603 may be, but is not limited to, ROM or RAM, or EEPROM, CD-ROM, or other optical disk storage, optical disk storage (including compact disk, laser disk, optical disk, digital versatile disk, blu-ray disk, etc.), magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer.

It should be noted that the memory may exist independently and be connected to the processor through the communication line 602. The memory may also be integrated with the processor.

Wherein the memory 603 is used for storing a computer program. The processor 601 is configured to execute a computer program stored in the memory 603, so as to implement a method of a related network element provided by any one of the method embodiments of the present application.

It should be noted that the processor 601 may include one or more CPUs, such as CPU0 and CPU1 in fig. 6. Further, fig. 6 is merely an example of one network device, and does not limit the specific structure of the network device. For example, the network device may also include other functional modules.

The embodiment of the application provides a data transmission method adjacent to service, which aims to meet the problem of QoS diversification requirements of application, and performs QoS requirement management and control based on QoS flow, and determines a Uu interface communication link (such as DRB) and a PC5 interface communication link (such as SLRB) by mapping Uu QoS parameters to PC5 QoS parameters, so as to solve the problem that service data transmission cannot be completed due to unmatched QoS parameters of the Uu interface communication link and the PC5 interface communication link in the conventional technology.

The following describes a data transmission method of proximity services provided by the embodiment of the present application specifically with reference to the accompanying drawings:

fig. 7 illustrates a method for transmitting data in proximity to a service according to an embodiment of the present application, which may be based on the foregoing architecture, as described below.

S701, the relay UE acquires a correspondence between the first communication link and the second communication link.

The first communication link may be a Uu interface communication link, where the Uu interface communication link refers to a communication link established between the relay UE and the access network device through a Uu interface, and may be used to transmit data of the first service between the relay UE and the access network device. For example, the first communication link may be a data radio bearer (data radio bearer, DRB). The DRB is used to transmit data of the first service between the relay UE and the access network device.

Wherein the second communication link may be a PC5 interface communication link for transmitting data of the first service between the relay UE and the remote UE. For example, the second communication link may be a side link radio bearer (sidelink radio bearer, SLRB).

It should be noted that, for the specific description of the DRB and the SLRB, reference may be made to explanation and explanation in the conventional art, and no detailed description is given here.

The first traffic may be traffic that the remote UE wishes to or is about to use for relay UE transmissions. The first service may be a specific service, for example, a video service, a voice service, a color ring service, a text transmission service, etc.; but may also be a certain type of service, such as a network slice service, an instant messaging service, a life service, etc.

Wherein S701 may be implemented as follows.

In the first mode, the relay UE directly receives the correspondence between the first communication link and the second communication link from the access network device.

It should be noted that, the correspondence may be explicit or implicit, for example, the same message carries the identification information of the first communication link and the identification information of the second communication link.

And in a second mode, the relay UE receives the identification information of the first communication link and the identification information of the second communication link from the access network equipment, and then establishes a corresponding relation between the first communication link and the second communication link according to the identification information of the first communication link and the identification information of the second communication link.

For example, the relay UE may receive configuration information of a first communication link and configuration information of a second communication link from the access network device, where the configuration information of the first communication link includes identification information of the first communication link, and the configuration information of the second communication link includes identification information of the second communication link.

Wherein the identification information of the first communication link is used to identify the first communication link, e.g., the first communication link is a first DRB, and the identification information of the first communication link is an ID (Identity) of the first DRB. The identification information of the second communication link is used to identify the second communication link, for example, the second communication link is the first SLRB, and the identification information of the second communication link is the ID of the first SLRB.

In a third mode, the relay UE receives a correspondence between the first communication link and at least two PC5 interface communication links from the access network device, then selects a second communication link from the received at least two PC5 interface communication links, and establishes a correspondence between the first communication link and the second communication link.

The relay UE may select, according to the condition (such as occupancy rate) that at least two PC5 interface communication links are occupied, a second communication link from the received at least two PC5 interface communication links; the relay UE may also be configured to determine the PC5 QoS parameters of the first service based on the received correspondence between the at least two PC5 interface communication links and the PC5 QoS parameters. A second communication link is selected from the received at least two PC5 interface communication links.

Wherein the PC5 QoS parameters of the first service include one or more of the following parameters: the method comprises the steps of resource type of a PC5 interface, scheduling priority of the PC5 interface, time delay of the PC5 interface, packet loss rate of the PC5 interface, maximum burst flow of the PC5 interface or time window size of the PC5 interface.

Wherein the resource types of the PC5 interface include one or more of the following: guaranteed bit rate (guaranteed bit rate, GBR) type, non-guaranteed bit rate Non-GBR type, and Delay-critical guaranteed bit rate (Delay critical guaranteed bit rate, delay-critical GBR) type. GBR type means that the corresponding bit rate can be maintained even in case of network resource shortage. The Non-GBR type means that the network does not provide the lowest transmission rate guarantee, that is, in case of congestion of the network, the traffic needs to withstand the reduced rate requirement. Delay-critical GBR refers to packet loss processing of service data exceeding a specified Delay limit, and is counted in statistics of packet loss rate; and normally transmitting the service data which does not exceed the specified time delay limit. The scheduling priority of the Uu interface defines the importance of the traffic, and determines whether the QoS flow is accepted or rejected by the Uu interface when the system resources are limited. The delay of the Uu interface defines the traffic demand for transmission delay. The packet loss Bao Lvding of Uu interface defines the requirement of service on packet loss rate. For example, delay sensitive services such as voice, video call, internet of things, internet of vehicles and the like are generally required to have high transmission rate, delay and packet loss rate. The maximum burst traffic of the Uu interface defines the traffic demand for the maximum burst traffic. The time window size of the Uu interface defines the traffic requirements for the time window size.

And fourthly, the relay UE determines a second communication link according to the received PC5 QoS parameters of the first service, receives the identification information of the first communication link from the access network equipment, and then establishes a corresponding relation between the first communication link and the second communication link.

For example, the relay UE may receive PC5 QoS parameters of the first traffic from the remote UE.

In a fifth mode, the relay UE receives the identification information of the first communication link from the access network device, receives the identification information of the second communication link from the remote UE, and then establishes a correspondence between the first communication link and the second communication link.

For example, the relay UE may receive configuration information of the second communication link from the remote UE, where the configuration information of the second communication link includes identification information of the second communication link.

S702, the relay UE transmits data of a first service of the remote UE according to the corresponding relation between the first communication link and the second communication link.

It is noted that the transmission to which the present application relates may include transmission and/or reception without limiting the transmission direction.

Illustratively, in S702, the relay UE may receive uplink data of a first service from the remote UE and send the uplink data of the first service to the access network device; the relay UE may also receive downlink data for the first service from the access network device and send the downlink data for the first service to the remote UE.

For example, when uplink data of a first service from a remote UE arrives at a relay UE through a second communication link, the relay UE transmits the uplink data of the first service to an access network device through a first communication link having a correspondence with the second communication link. And when downlink data of a first service from the access network equipment reaches the relay UE through the first communication link, the relay UE transmits the downlink data of the first service to the remote UE through a second communication link which has a corresponding relation with the first communication link.

In the embodiment shown in fig. 7, the relay UE obtains a correspondence between a first communication link (such as DRB) and a second communication link (such as SLRB), so that service data of the first service can be transmitted between the relay UE and the access network device through the first communication link and between the remote UE and the relay UE through the second communication link according to the correspondence, respectively. By the scheme, the problem that service data transmission cannot be completed due to the fact that QoS parameters of a first communication link (such as DRB) and a second communication link (such as SLRB) are not matched in the conventional technology can be solved.

Optionally, in an implementation scenario of the foregoing embodiment, before acquiring the correspondence between the first communication link and the second communication link, the foregoing method further includes: a first communication link and a second communication link are determined.

Specifically, the first communication link and the second communication link may be determined by three ways:

mode (1), the access network device determines a first communication link and a second communication link.

In one implementation, the access network device may determine, according to Uu QoS requirement information of the first service, to transmit data of the first service through a first communication link between the access network device and the relay UE, and determine the second communication link according to a correspondence between the first Uu QoS parameter and the first PC5 QoS parameter, and Uu QoS requirement information of the first service.

The Uu QoS requirement information of the first service refers to a QoS configuration requirement of the first service on a Uu interface. The Uu QoS requirement information of the first service includes at least one or more of the following parameters of the Uu interface for the first service: the resource type of the Uu interface, the scheduling priority of the Uu interface, the time delay of the Uu interface, the packet loss rate of the Uu interface, the maximum burst flow of the Uu interface or the time window size of the Uu interface.

Wherein the resource type of Uu interface may include one or more of the following: GBR type, non-GBR type, and Delay-critical GBR type. For example, uu QoS requirement information of the first service in the embodiment of the present application may be received by the access network device from the SMF network element through the PDU session. The first Uu QoS parameter is used for transmitting data of a first service through a Uu interface between the relay UE and the access network equipment; the first PC5 QoS parameter is used to transmit data of the first service over a PC5 interface between the relay UE and the remote UE.

For example, in the embodiment of the present application, the access network device may select, from a plurality of Uu interface communication links that may be used by the access network device, a Uu interface communication link (such as a first communication link) that best meets one or more QoS parameter requirements of the first service on a resource type, a scheduling priority, a delay, a packet loss rate, a maximum burst flow, or a time window size of the Uu interface, and perform transmission of service data of the first service between the access network device and the relay UE. And after the access network device determines the first communication link, the access network device may determine a PC5 QoS parameter (e.g., a first PC5 QoS parameter) corresponding to a Uu QoS parameter (e.g., a first Uu QoS parameter) that can be satisfied by the first communication link, thereby selecting one PC5 interface communication link (e.g., a second communication link) that can satisfy the first PC5 QoS parameter from among a plurality of PC5 interface communication links that can be used by the relay UE. It should be noted that, the specific description of the mode (1) may refer to the embodiment shown in fig. 8 or fig. 9, and will not be repeated.

Mode (2), the access network device determines the first communication link and notifies the relay UE of the information of the first communication link. The relay UE determines a second communication link from the candidate PC5 interface communication links.

In particular, the access network device may determine to transmit data of the first service over the first communication link between the access network device and the relay UE according to Uu QoS requirement information of the first service.

Wherein the candidate PC5 interface communication link may be determined by the access network device and the relay UE is informed of the information of the candidate PC5 interface communication link. The information of the candidate PC5 interface communication link may be identification information of the candidate PC5 interface communication link, such as an ID of the candidate PC5 interface communication link.

In one example, the access network device may determine at least two PC5 interface communication links (i.e., candidate PC5 interface communication links) of the remote UE according to the correspondence of the first Uu QoS parameter and the first PC5 QoS parameter, and Uu QoS requirement information of at least two services (e.g., a first service, a second service, and a third service) of the remote UE, and inform the relay UE of identification information of the at least two PC5 interface communication links for the relay UE to select the second communication link from.

The corresponding relation between the first Uu QoS parameter and the first PC5 QoS parameter may be obtained by the access network device from the PCF network element.

In another example, the access network device may determine at least two PC5 interface communication links (i.e., candidate PC5 interface communication links) from which the relay UE selects the second communication link based on the correspondence of the first Uu QoS parameter to the first PC5 QoS parameter and Uu QoS requirement information for traffic of the same or similar QoS requirements for different remote UEs (e.g., remote UE 1, remote UE 2, and remote UE 3).

It should be noted that, the specific description of the mode (2) may refer to the embodiment shown in fig. 10 or fig. 11, and will not be repeated.

Mode (3), the access network device determines the first communication link and notifies the relay UE of the information of the first communication link. The remote UE or relay UE determines the second communication link according to the PC5 QoS parameters of the first service.

For example, the access network device may determine the first communication link according to the correspondence between the first Uu QoS parameter and the first PC5 QoS parameter, and Uu QoS requirement information of the first service.

The information of the first communication link may be identification information of the first communication link or configuration information of the first communication link.

It should be noted that, the specific description of the mode (3) may refer to the embodiment shown in fig. 12 or fig. 13, and will not be repeated.

Optionally, in another implementation scenario of the above embodiment, the method further includes: the remote UE determines to transmit the first traffic using the relay UE.

In one example, the remote UE may determine to transmit the first service using the relay UE based on one or more of capability information of the remote UE, subscription information of the first service, subscription information of the remote UE, or the like. For example, when there is a first service transmission requirement, the remote UE determines to transmit the first service using the relay UE according to the capability information of the remote UE to support the relay mode to transmit the service and the subscription information allowing the relay mode to transmit the first service.

The embodiments shown in fig. 8 and 9 are described taking the example that the first communication link is the first DRB and the second communication link is the first SLRB.

Referring to fig. 8, a method for transmitting data of proximity services according to an embodiment of the present application is described below.

S801, the access network equipment receives Uu QoS requirement information of a first service.

The Uu QoS requirement information of the first service may refer to a QoS configuration requirement of the first service on the Uu interface.

Wherein the Uu QoS requirement information of the first service may include one or more of the following parameters of the Uu interface by the first service: the resource type of the Uu interface, the scheduling priority of the Uu interface, the time delay of the Uu interface, the packet loss rate of the Uu interface, the maximum burst flow of the Uu interface or the time window size of the Uu interface. The resource types of the Uu interface may include one or more of the following: GBR type, non-GBR type, and latency critical guaranteed bit rate (Delay critical guaranteed bit rate, delay-critical GBR) type.

In particular, uu QoS requirement information of the first service may be represented by a 5G QoS identification (5G QoS Indication,5QI). Table 1 shows a mapping relationship of 5QI and Uu QoS parameters.

TABLE 1

Alternatively, the Uu QoS requirement information of the first service may be represented in other forms, and the specific form of the Uu QoS requirement information is not specifically limited in the embodiment of the present application.

S802, the access network equipment determines to transmit the data of the first service through the first DRB according to Uu QoS requirement information of the first service.

The first DRB may satisfy a QoS configuration requirement of the first service on the Uu interface, where the QoS configuration requirement may include a configuration requirement of QoS parameters such as a resource type, a scheduling priority, a delay, a packet loss rate, a maximum burst flow, or a time window size of the Uu interface, for example.

It is understood that the service data transmission between the relay UE and the access network device may be performed through multiple communication links (such as multiple DRBs). Different communication links may be of different resource types, may achieve different scheduling priorities, delays, packet loss rates, maximum burst traffic, or may use different size time windows. The access network device may select, from the plurality of DRBs between the relay UE and the access network device, a DRB capable of meeting the Uu QoS configuration requirement of the first service, such as the first DRB, according to Uu QoS requirement information of the first service.

S803, the access network equipment determines a first SLRB according to the corresponding relation between the first Uu QoS parameters and the first PC5 QoS parameters and Uu QoS requirement information of the first service.

Wherein the first SLRB may be used to transmit data of the first service between the relay UE and the remote UE.

The first Uu QoS parameter may be used to transmit data of the first service over a Uu interface between the relay UE and the access network equipment.

The first PC5 QoS parameter (i.e., the PC5 QoS parameter of the first service) may be used to transmit data of the first service over a PC5 interface between the relay UE and the remote UE.

Illustratively, the correspondence between Uu QoS parameters and PC5 QoS parameters that may be acquired and stored by the access network device may be expressed in the form of a correspondence between 5QI and PC5 QoS identification (PQI).

It should be noted that, the correspondence between Uu QoS parameters and PC5 QoS parameters mentioned in the present application may include one or more correspondences, where each correspondence is a correspondence between one or a group of Uu QoS parameters and one or a group of PC5 QoS parameters. For example, the correspondence between Uu QoS parameters and PC5 QoS parameters includes: 5 qi=1 corresponds to pqi=1; 5 qi=2 corresponds to pqi=2.

Table 2 shows a mapping relationship between PQI and PC5 QoS parameters.

TABLE 2

Or, the corresponding relationship between Uu QoS parameters and PC5 QoS parameters may be expressed in other forms, and the specific expression form of the corresponding relationship between Uu QoS parameters and PC5 QoS parameters in the embodiment of the present application is not specifically limited.

In general, traffic data transmission between the relay UE and the remote UE may be performed through multiple communication links (e.g., multiple SLRBs). Different communication links may be of different resource types, may achieve different scheduling priorities, delays, packet loss rates, maximum burst traffic, or may use different size time windows.

In one example, the access network device may obtain and store a correspondence of Uu QoS parameters to PC5 QoS parameters. Further, the access network device may correspond the Uu QoS requirement information of the first service to the PC5 QoS parameter according to the corresponding relationship between the Uu QoS parameter and the PC5 QoS parameter and the Uu QoS requirement information of the first service. For example, the access network device selects one or a group of Uu QoS parameters from a corresponding relation of Uu QoS parameters and PC5 QoS parameters, which best satisfies one or more QoS parameter requirements of the first service on a resource type, a scheduling priority, a delay, a packet loss rate, a maximum burst flow, or a time window size of the Uu interface, and determines one or a group of PC5 QoS parameters corresponding to the one or the group of Uu QoS parameters. Then, based on the determined one or a set of PC5 QoS parameters, a first SLRB capable of satisfying the one or a set of PC5 QoS parameters is determined. The first SLRB may satisfy QoS configuration requirements of the first service for a PC5 interface between the remote UE and the relay UE.

The PC5 QoS parameters and Uu QoS parameters with the corresponding relationship can generally meet the configuration requirements of the service on QoS parameters such as resource type, scheduling priority, delay, packet loss rate, maximum burst traffic or time window size.

For example, uu QoS requirement information of the first service of the remote UE includes the following parameter requirements: the resource type is GRB. The scheduling priority is 30, the time delay requirement is not higher than 50ms, and the packet loss rate is not higher than 10 ^-3 The average time window size is 2000ms. The corresponding relation between Uu QoS parameters and PC5 QoS parameters stored in the access network device includes a first Uu QoS parameter (e.g. 5qi=3) capable of meeting the configuration requirement of the first service QoS parameter, and a first PC5 QoS parameter (e.g. pqi=3) matched with the first Uu QoS parameter. The first Uu QoS parameter may satisfy a configuration requirement of the first service on QoS parameters such as a resource type of a Uu interface, a scheduling priority of the Uu interface, a delay of the Uu interface, a packet loss rate of the Uu interface, a maximum burst traffic of the Uu interface, or a time window size of the Uu interface. The first PC5 QoS parameter may satisfy a configuration requirement of the first service on QoS parameters such as a resource type of the PC5 interface, a scheduling priority of the PC5 interface, a delay of the PC5 interface, a packet loss rate of the PC5 interface, a maximum burst traffic of the PC5 interface, or a time window size of the PC5 interface.

In one example, the correspondence of Uu QoS parameters and PC5QoS parameters may be pre-stored in the access network device.

In another example, the correspondence of Uu QoS parameters to PC5QoS parameters may also be created and maintained by the PCF. The access network device can obtain the corresponding relation between Uu QoS parameters and PC5QoS parameters from the PCF network element through the AMF network element.

For example, the access network device may obtain the correspondence between Uu QoS parameters and PC5QoS parameters through steps S800-1 and S800-2 shown in fig. 8:

s800-1, PCF network element sends Uu QoS parameter and PC5QoS parameter corresponding relation to AMF network element. Correspondingly, the AMF network element receives the corresponding relation between Uu QoS parameters and PC5QoS parameters from the PCF network element.

The PCF network element may receive an input of a network maintainer to maintain a correspondence between Uu QoS parameters and PC5QoS parameters. Or, the PCF network element may also generate and maintain the corresponding relationship between the Uu QoS parameters and the PC5QoS parameters by itself, for example, the PCF network element generates the corresponding relationship between the Uu QoS parameters and the PC5QoS parameters according to the subscription data of the service and the transmission capacities of the remote UE and the relay UE. Or, the PCF network element may obtain the corresponding relationship between the Uu QoS parameter and the PC5QoS parameter in other manners, and the generation manner of the corresponding relationship between the Uu QoS parameter and the PC5QoS parameter in the embodiment of the present application is not specifically limited.

S800-2, AMF network element sends the corresponding relation between Uu QoS parameter and PC5 QoS parameter to access network equipment.

Correspondingly, the access network device receives the corresponding relation between Uu QoS parameters and PC5 QoS parameters from the AMF network element.

In an exemplary process that the remote UE registers with the AMF network element, the remote UE carries capability information for indicating that the remote UE supports direct communication using the PC5 interface in a registration request message, and the AMF network element may determine, according to the capability information, a correspondence between a Uu QoS parameter and a PC5 QoS parameter sent to the access network device.

In addition, the AMF network element may further send Uu QoS requirement information of the first service to the access network device. Further, the AMF network element may also forward the QFI allocated by the SMF network element for the QoS flow to the access network device. The Uu QoS requirement information and QFI of the first service may be sent to the access network device by the AMF network element when the corresponding relationship between the Uu QoS parameter and the PC5 QoS parameter is sent, or may be sent to the access network device by the AMF network element alone.

In some embodiments, the AMF network element may further send to the access network device a PLMN list that may be used by the remote UE for ProSe communication, radio band information that may be used by the remote UE outside of network coverage, qoS requirement information mapped to one or more of rules of PQI or standardized PQI, etc.

It should be noted that, the AMF network element may send the corresponding relationship between the Uu QoS parameter and the PC5 QoS parameter to the access network device in the process of registering the remote UE with the AMF network element, or may send the corresponding relationship between the Uu QoS parameter and the PC5 QoS parameter to the access network device in other processes of the remote UE, for example, a service request process, a PDU session establishment process, or a PDU session recovery process, which is not limited in the present application.

S804, the access network equipment sends first communication link information to the relay UE.

The first communication link information may be used to characterize a correspondence between the first DRB and the first SLRB.

Accordingly, the relay UE receives the first communication link information from the access network device.

The first DRB is used for transmitting data of a first service between the relay UE and the access network equipment, and the first SLRB is used for transmitting data of the first service between the relay UE and the remote UE. The correspondence between the first DRB and the first SLRB is established by the access network device. It can be understood that, after the access network device obtains the first DRB, the first SLRB and the QFI, a correspondence between the first DRB and the first SLRB can be established for the service data corresponding to the QFI, so as to be used for transmitting the service data of the service through a transmission channel formed by the first DRB and the first SLRB.

S805, the relay UE sends configuration information of the first SLRB to the remote UE.

Accordingly, the remote UE receives configuration information of the first SLRB from the relay UE.

In the embodiment of the application, the relay UE may send the configuration information of the first SLRB to the remote UE through the PC5 interface. The configuration information of the first SLRB is used for transmitting data of the first service between the remote UE and the relay UE by using the first SLRB.

Wherein, the configuration information of the first SLRB may include one or more of the following: identification information of the first SLRB, configuration information of the RLC layer in the PC5 interface protocol stack or configuration information of the MAC layer in the PC5 interface protocol stack.

The identification information of the first SLRB may be used by the remote UE to determine a PC5 interface communication link between the relay UE and the remote UE for PC5 communication.

The configuration information of the RLC layer in the PC5 interface protocol stack and the configuration information of the MAC layer in the PC5 interface protocol stack may be used to unify the processing modes of the RLC layer and the MAC layer for the remote UE and the relay UE, for example, unify the splitting and reassembling modes of the data packet, and the retransmission modes of the unified data packet.

S806, the relay UE transmits data of the first service of the remote UE.

Wherein the transmission to which the present application relates may include transmission and/or reception without limiting the transmission direction.

For example, when uplink data of a first service from a remote UE arrives at a relay UE through a first SLRB (as shown by S806-a in fig. 8), the relay UE may determine to send the uplink data of the first service to an access network device through a first DRB corresponding to the first SLRB according to a correspondence between the first DRB and the first SLRB characterized by the first communication link information (as shown by S806-b in fig. 8).

When downlink data of a first service from the access network device arrives at the relay UE through the first DRB (as shown in S806-b in fig. 8), the relay UE may determine, according to a correspondence between the first DRB and the first SLRB represented by the first communication link information, to send the downlink data of the first service to the remote UE through the first SLRB corresponding to the first DRB (as shown in S806-a in fig. 8).

Alternatively, in another embodiment, as shown in fig. 9, the method provided in this embodiment may be based on the method shown in fig. 8, and S804 is replaced with S901 and S902:

s901, the access network equipment sends second communication link information to the relay UE.

S902, the relay UE establishes a corresponding relation between the first DRB and the first SLRB according to the second communication link information.

In one example, the second communication link information includes identification information of the first DRB and identification information of the first SLRB. For example, the second communication link information includes configuration information of the first DRB and configuration information of the first SLRB. Wherein, the configuration information of the first DRB may include one or more of: the identification information of the first DRB, the configuration information of the RLC layer in the Uu interface protocol stack or the configuration information of the MAC layer in the Uu interface protocol stack. The configuration information of the first SLRB may include one or more of: identification information of the first SLRB, configuration information of the RLC layer in the PC5 interface protocol stack or configuration information of the MAC layer in the PC5 interface protocol stack. The identification information of the first DRB may be an ID of the first DRB, and the identification information of the first SLRB may be an ID of the first SLRB.

For example, the identification information of the DRB and/or the identification information of the SLRB may be represented by an ID of the RLC channel, and it is apparent that the identification information of the DRB or the identification information of the SLRB may also be represented in other forms, without limitation.

In the embodiment shown in fig. 8 or fig. 9, the access network device determines, according to Uu QoS requirement information of the first service and a correspondence between Uu QoS parameters and PC5 QoS parameters, a first communication link (i.e., a first DRB) for transmitting service data of the first service between the relay UE and the access network device, and a second communication link (i.e., a first SLRB) for transmitting service data of the first service between the remote UE and the relay UE, so as to solve a problem that in the conventional technology, service data transmission cannot be completed due to mismatch of QoS parameters of the Uu interface communication link and the PC5 interface communication link.

The embodiments shown in fig. 10 and 11 are described by taking the example that the first communication link is the first DRB and the second communication link is the first SLRB as follows.

Fig. 10 illustrates another approach to data transmission by proximity services provided by the present application, which may be based on the embodiment illustrated in fig. 9, and further replaces S803 with S1001, S901 with S1002, and S902 with S1003 and S1004, as described in detail below.

S1001, the access network equipment determines at least two PC5 interface communication links of the remote UE according to the corresponding relation between the first Uu QoS parameter and the first PC5 QoS parameter and Uu QoS requirement information of the first service.

That is, there may be multiple PC5 interface communication links (e.g., SLRBs) capable of meeting the QoS configuration requirements of the first service of the remote UE (e.g., remote UE 1) for the PC5 interface between the remote UE 1 and the relay UE. The access network device may correspond the Uu QoS requirement information of the first service to the PC5 QoS parameter according to the correspondence between the Uu QoS parameter and the PC5 QoS parameter and the Uu QoS requirement information of the first service. For example, the access network device selects one or a group of Uu QoS parameters from the corresponding relation between Uu QoS parameters and PC5 QoS parameters, which best satisfies one or more QoS parameter requirements of the first service on a resource type, a scheduling priority, a delay, a packet loss rate, a maximum burst flow, or a time window size of the Uu interface, and determines a plurality of or a plurality of groups of PC5 QoS parameters corresponding to the one or the group of Uu QoS parameters. At least two PC5 interface communication links capable of satisfying the plurality or plurality of sets of PC5 QoS parameters are then determined based on the determined plurality or plurality of sets of PC5 QoS parameters. The at least two PC5 interface communication links may each meet the QoS configuration requirements of the first service for the PC5 interface between the remote UE 1 and the relay UE.

S1002, the access network equipment sends third communication link information to the relay UE.

Accordingly, the relay UE receives the third communication link information from the access network device.

The third communication link information is used for representing the first corresponding relation. The first correspondence is a correspondence between the first DRB and at least two PC5 interface communication links of the remote UE.

For example, the third communication link information may be transmitted to the relay UE by the access network device in a table form, or may be transmitted to the relay UE in another form, which is not limited. Table 3 below is only described in one form of table, but the table may be in other forms and is not limited thereto.

TABLE 3 Table 3

Wherein the first DRB in table 3 is a communication link determined by the access network device for transmitting data of the first service between the access network device and the relay UE. The first, second and third SLRBs are candidate communication links determined by the access network device that may be used to relay data of the first service between the UE and the remote UE 1. The correspondence relationship between the "Uu interface communication link" and the "PC5 interface communication link" in table 3 is a first correspondence relationship.

S1003, the relay UE determines a first SLRB from at least two PC5 interface communication links of the remote UE characterized by the third communication link information.

In one example, the relay UE may determine a second communication link, such as a first SLRB, for transmitting data of the first service from at least two PC5 interface communication links of the remote UE acquired from the access network device according to a condition (such as an occupancy) that the at least two PC5 interface communication links are occupied. For example, the relay UE may monitor the usage of at least two PC5 interface communication links of the remote UE, and select the PC5 interface communication link with the smallest occupancy rate from the usage as the second communication link. The occupancy rate of at least two PC5 interface communication links of the remote UE refers to a time ratio that the received power of the communication link monitored by the relay UE is greater than a preset power in a preset time period. Or the time ratio that the signal intensity of the communication link monitored by the relay UE and received by the remote UE is smaller than the preset signal intensity.

S1004, the relay UE establishes a correspondence between the first DRB and the first SLRB.

In one example, in the step S1002, the sending, by the access network device, third communication link information to the relay UE includes: the identification information of the first DRB and the identification information of at least two PC5 interface communication links of the remote UE. In this case, the relay UE may determine the first SLRB from at least two PC5 interface communication links of the remote UE and establish a correspondence between the first DRB and the first SLRB.

For the embodiment shown in fig. 10, when downlink data of a first service from an access network device arrives at a relay UE through a first DRB, the relay UE may determine, according to an SLRB tag (e.g., identification information of a first SLRB) added by the access network device in a downlink data packet of the first service, which SLRB is used to transmit the downlink data packet of the first service to a remote UE. When uplink data of a first service from a remote UE arrives at a relay UE, the relay UE transmits the uplink data packet of the first service to an access network device through a first DRB (data packet radio bearer) no matter whether the uplink data packet is transmitted to the relay UE through the first SLRB, the second SLRB or the third SLRB.

Optionally, in another example, as shown in fig. 11, the method provided in this embodiment may further include steps S1101-S1102 on the basis of the method shown in fig. 10, and in addition, S1003 is replaced with S1103, which is described in detail below.

S1101, the access network device sends the PC5 QoS parameter of the first service to the relay UE.

Accordingly, the relay UE receives the PC5 QoS parameters of the first service from the access network device.

The PC5 QoS parameter of the first service may be determined by the access network device according to Uu QoS requirement information of the first service in combination with a correspondence between the Uu QoS parameter and the PC5 QoS parameter. For example, the PC5 QoS parameter of the first service may be a PC5 QoS parameter with the highest matching degree with Uu QoS requirement information of the first service in a correspondence between Uu QoS parameters and PC5 QoS parameters. For example, uu QoS requirement information of the first service uses 5QI:3, the PC5 QoS parameters of the first service with the highest matching degree can be represented by PQI: 3.

S1102, the access network equipment sends a second corresponding relation to the relay UE. The second correspondence is a correspondence between at least two PC5 interface communication links of the remote UE characterized by the third communication link information and the PC5 QoS parameters.

Correspondingly, the relay UE receives the second correspondence from the access network device.

In some embodiments, the second correspondence may be sent by the access network device to the relay UE together with the first correspondence through third communication link information. For example, the third communication link information may be transmitted by the access network device to the relay UE in the form of a table. As shown in table 4 below:

TABLE 4 Table 4

Wherein the first DRB in table 4 is a communication link determined by the access network device for transmitting data of the first service between the access network device and the relay UE. The first, second, and third SLRBs are candidate communication links determined by the access network device that may be used to relay data of the first service between the UE and the remote UE. PQI: 3. PQI:4 and PQI: and 5 is a PC5 QoS parameter corresponding to the first SLRB, the second SLRB and the third SLRB respectively. The correspondence relationship between the "Uu interface communication link" and the "PC5 interface communication link" in table 4 is a first correspondence relationship. The correspondence relationship between the "PC5 interface communication link" and the "PC5 QoS parameters" in table 4 is a second correspondence relationship.

S1103, the relay UE determines a first SLRB from at least two PC5 interface communication links of the remote UE represented by the third communication link information according to the PC5 QoS parameters of the first service, the first corresponding relation and the second corresponding relation.

In one example, the relay UE may know that the first SLRB, the second SLRB, and the third SLRB are candidate communication links that may be used for transmitting data of the first service between the relay UE and the remote UE according to the first correspondence, and may respectively reach PQI according to the second correspondence: 3. PQI:4 and PQI:5, and the PC5 QoS parameter of the first service is PQI:3, so, in combination with the above information, the relay UE can determine that, among the first SLRB, the second SLRB and the third SLRB, the first SLRB is the most capable of meeting the PC5 interface transmission requirement of the first service.

The data transmission method of the adjacent service provided by the application is based on QoS flow to control QoS requirement. In one example, the access network device may map different QoS flows onto the same DRB when mapping QoS flows to DRBs. For example, qoS flows mapped onto the same DRB have partially similar or identical QoS parameters. For example, different QoS flows have the same scheduling priority, or similar delay or packet loss rates, etc.

Thus, assuming that the remote UE has a first service and a second service transmission requirement, the QoS flows used by the first service and the second service are different, but the partial QoS parameters are similar or identical, the QoS flows of the first service and the second service may be mapped to the same DRB for transmission. In this case, in step S1002 described above, the third communication link information transmitted by the access network device to the relay UE may include the first correspondence relationship and the second correspondence relationship. Wherein the first correspondence is a correspondence between the first DRB and at least two PC5 interface communication links (including a second communication link (e.g., a first SLRB) and a third communication link (e.g., a second SLRB)) of the remote UE 1; the second correspondence is a correspondence between each of the PC5 interface communication links and the PC5 QoS parameters in the first correspondence. As shown in table 5 below:

TABLE 5

The first DRB in table 5 above is a Uu interface communication link determined by the access network equipment for transmitting data of the first service and the second service of the remote UE 1 between the access network equipment and the relay UE. The first DRB is determined by the access network device according to the received Uu QoS requirement information of the first service and Uu QoS requirement information of the second service. The first and second SLRBs are PC5 interface communication links determined by the access network device for transmitting data of the first and second traffic between the remote UE 1 and the relay UE, respectively. The first SLRB is determined by the access network device according to the corresponding relation between the first Uu QoS parameters and the first PC5 QoS parameters and Uu QoS requirement information of the first service. The second SLRB is determined by the access network device according to the corresponding relationship between the second Uu QoS parameter and the second PC5 QoS parameter, and Uu QoS requirement information of the second service. The second Uu QoS parameter is used for transmitting data of the second service through a Uu interface between the relay UE and the access network device, and the second PC5 QoS parameter is used for transmitting data of the second service through a PC5 interface between the relay UE and the remote UE 1. Regarding the method for determining the SLRB according to the correspondence between Uu QoS parameters and PC5 QoS parameters and Uu QoS requirement information of the service, reference may be made to the description above, and details are not repeated here.

In this case, the relay UE may determine a second communication link, i.e., a first SLRB, capable of satisfying the transmission requirement of the first service from among the first SLRB and the second SLRB in combination with the PC5 QoS parameter of the first service according to the third communication link information.

Further optionally, if the remote UE 1 has a third traffic transmission requirement in addition to the first traffic and the second traffic transmission requirement, the QoS requirements of the first traffic, the second traffic and the third traffic are the same or similar, and then the first traffic, the second traffic and the third traffic may be mapped to the same QoS flow for transmission.

In this case, in step S1002 described above, the third communication link information transmitted by the access network device to the relay UE may include the first correspondence relationship and the second correspondence relationship. Wherein the first correspondence is a correspondence between the first DRB and at least two PC5 interface communication links (including a second communication link (e.g., a first SLRB), a third communication link (e.g., a second SLRB), and a fourth communication link (e.g., a third SLRB)) of the remote UE 1; the second correspondence is a correspondence between each of the PC5 interface communication links and the PC5 QoS parameters in the first correspondence. In this case, the first DRB is a Uu interface communication link determined by the access network equipment for transmitting data of the first, second and third traffic of the remote UE 1 between the access network equipment and the relay UE. The first DRB is determined by the access network device according to the received Uu QoS requirement information of the first service, uu QoS requirement information of the second service, and Uu QoS requirement information of the third service. The first, second and third SLRBs are PC5 interface communication links determined by the access network device for transmitting data of the first, second and third services between the remote UE 1 and the relay UE, respectively. The first SLRB is determined by the access network device according to the corresponding relation between the first Uu QoS parameters and the first PC5 QoS parameters and Uu QoS requirement information of the first service. The second SLRB is determined by the access network device according to the corresponding relationship between the second Uu QoS parameter and the second PC5 QoS parameter, and Uu QoS requirement information of the second service. The third SLRB is determined by the access network device according to the corresponding relationship between the third Uu QoS parameter and the third PC5 QoS parameter, and Uu QoS requirement information of the third service. The second Uu QoS parameter is used for transmitting data of the second service through a Uu interface between the relay UE and the access network device, and the second PC5 QoS parameter is used for transmitting data of the second service through a PC5 interface between the relay UE and the remote UE 1. The third Uu QoS parameter is used for transmitting data of the third service through a Uu interface between the relay UE and the access network device, and the third PC5 QoS parameter is used for transmitting data of the third service through a PC5 interface between the relay UE and the remote UE 1. In this case, the relay UE may determine a second communication link, i.e., a first SLRB, capable of satisfying the transmission requirement of the first service from among the first, second, and third SLRBs in combination with the PC5 QoS parameter of the first service according to the communication link information. In this case, when downlink data of the first service from the access network device reaches the relay UE through the first DRB, the relay UE may determine which SLRB to use to transmit the downlink data packet of the first service to the remote UE according to PC5 QoS parameter information (e.g., PQI: 3) added by the access network device to the downlink data packet of the first service. For example, the PC5 QoS parameter information may be added in a packet header transmitted from the PDCP layer to the RLC layer, or in a packet header transmitted from the adaptation layer to the RLC layer. When uplink data of a first service from a remote UE arrives at a relay UE, the relay UE transmits the uplink data packet of the first service to an access network device through a first DRB (data packet radio bearer) no matter whether the uplink data packet is transmitted to the relay UE through the first SLRB, the second SLRB or the third SLRB.

In another example, if the remote UE 1 and the remote UE 2 have a first traffic and a fourth traffic transmission requirement, respectively, the QoS requirements of the first traffic and the fourth traffic are the same or similar, then the first traffic and the fourth traffic may be mapped to the same QoS flow for transmission.

In this case, in the above step S1002, the third communication link information sent by the access network device to the relay UE may include a correspondence between the first DRB and at least two PC5 interface communication links, including the second communication link (e.g., the first SLRB) and the fourth communication link (e.g., the fifth SLRB). As shown in table 6 below:

TABLE 6

Wherein the first DRB in table 6 is a Uu interface communication link determined by the access network equipment for transmitting data of the first traffic of the remote UE 1 and the fourth traffic of the remote UE 2 between the access network equipment and the relay UE. The first DRB is determined by the access network device according to the received Uu QoS requirement information of the first service and Uu QoS requirement information of the fourth service. The first SLRB is a PC5 interface communication link determined by the access network device for transmitting data of the first service between the remote UE 1 and the relay UE, respectively. The first SLRB is determined by the access network device according to the corresponding relation between the first Uu QoS parameters and the first PC5 QoS parameters and Uu QoS requirement information of the first service. The second SLRB is a PC5 interface communication link determined by the access network device for transmitting data of the fourth service between the remote UE 2 and the relay UE, respectively. The second SLRB is determined by the access network device according to the correspondence between the fourth Uu QoS parameter and the fourth PC5 QoS parameter, and Uu QoS requirement information of the fourth service. The fourth Uu QoS parameter is used for transmitting data of a fourth service through a Uu interface between the relay UE and the access network device, and the fourth PC5 QoS parameter is used for transmitting data of the fourth service through a PC5 interface between the relay UE and the remote UE 1.

In this case, the relay UE may determine a second communication link, i.e., a first SLRB, capable of satisfying the first traffic transmission requirement from among the first SLRB and the second SLRB in combination with the identification information of the remote UE 1 according to the third communication link information. In this case, when downlink data of the first service from the access network device arrives at the relay UE through the first DRB, the relay UE may determine which SLRB to use to transmit the downlink data packet of the first service to the remote UE according to the identification information (e.g., remote UE 1) of the remote UE added by the access network device in the downlink data packet of the first service. When uplink data of a first service from a remote UE arrives at a relay UE, the relay UE transmits the uplink data packet of the first service to an access network device through a first DRB, regardless of whether the uplink data packet is transmitted to the relay UE through the first SLRB or the second SLRB.

In one example, the access network device may also determine the correspondence of the first Uu QoS parameter with the first PC5 QoS parameter by itself. For example, in the process that the remote UE accesses the 5GC through the relay UE and establishes or updates the PDU session, the access network device may determine the correspondence between the first Uu QoS parameter and the first PC5 QoS parameter according to the PC5 QoS parameter (i.e., the first PC5 QoS parameter) of the first service of the remote UE sent by the AMF network element from the PCF network element and the Uu QoS parameter (e.g., the first Uu QoS parameter) of the first service sent by the AMF network element. For example, the access network device may itself map the first PC5 QoS parameters with the first Uu QoS parameters.

In this case, in general, during the process that the remote UE accesses the 5GC through the relay UE and establishes or updates the PDU session, the PCF network element may send Uu QoS requirement information of the first service to the SMF network element through PCC rules. The SMF network element maps the data flow to the QoS flow according to the PCC rule, and sends the QoS flow information and Uu QoS parameters of the first service to the access network equipment through an N2 message. The access network device may map the Uu QoS parameter of the first service with one PC5QoS parameter of a plurality of PC5QoS parameters from the PCF forwarded by the access network device via the AMF received by the N1 message. And obtaining the corresponding relation between the first PC5QoS parameter and the first Uu QoS parameter. Then, the access network device may determine a first DRB and a first SLRB according to the correspondence between the first PC5QoS parameter and the first Uu QoS parameter; alternatively, a first DRB and at least two PC5 communication links, etc. are determined.

It is understood that the communication mode of the PC5 interface used by the relay UE with the remote UE may be an ad hoc mode or an autonomous resource scheduling mode. That is, the PC5 interface communication link may be selected by the relay UE or the remote UE from a pool of radio resources pre-configured by an access network device (e.g., a base station) or a core network device (e.g., a PCF network element). The wireless resource pool comprises a plurality of SLRBs which can be selected by the relay UE or the remote UE. In this case, as described in the embodiments corresponding to fig. 10, 11, table 5 or 6 above, the access network device does not directly allocate the first SLRB to the relay UE and the remote UE.

For the embodiments corresponding to fig. 10, 11 or table 5 or 6 above, determining, by the access network device, a first communication link (i.e., a first DRB) for transmitting traffic data of the first traffic between the relay UE and the access network device according to Uu QoS requirement information of the first traffic; according to Uu QoS requirement information of a first service and a corresponding relation between a first Uu QoS parameter and a first PC5 QoS parameter, an access network device determines at least two PC5 interface communication links so that relay UE can select a second communication link (namely a first SLRB) which is finally used for transmitting service data of the first service between remote UE and relay UE from the second communication link, and the problem that service data transmission cannot be completed due to the fact that QoS parameters of the Uu interface communication link and the PC5 interface communication link are not matched in the conventional technology is solved.

The embodiments shown in fig. 12 and 13 are described by taking the example that the first communication link is the first DRB and the second communication link is the first SLRB as follows.

Fig. 12 illustrates another proximity service data transmission method provided by the present application, in which the first SLRB is determined by the relay UE according to the PC5 QoS parameters of the first service. Specifically, the method may be based on the embodiment shown in FIG. 8, and further replaces S800-1, S800-2, and S801-S804 with S1202-S1205, as described in detail below.

S1201, the AMF network element sends the remote UE the PC5 QoS parameters of the first service of the remote UE from the PCF network element.

Accordingly, the remote UE receives the PC5 QoS parameters of the first service from the AMF network element.

For example, in the process that the remote UE accesses the 5GC through the relay UE and establishes or updates the PDU session, the PCF network element may send the PC5 QoS parameters of the first service to the AMF network element. The AMF network element may forward the PC5 QoS parameters of the first service to the remote UE via the access network device and the relay UE.

Wherein the PC5 QoS parameters of the first service include one or more of the following parameters: the method comprises the steps of resource type of a PC5 interface, scheduling priority of the PC5 interface, time delay of the PC5 interface, packet loss rate of the PC5 interface, maximum burst flow of the PC5 interface or time window size of the PC5 interface. Wherein the resource types of the PC5 interface include one or more of the following: GBR type, non-GBR type, and Delay-critical GBR type.

S1202, the remote UE sends the PC5 QoS parameters of the first service to the relay UE.

Accordingly, the relay UE receives the PC5 QoS parameters of the first service from the remote UE.

S1203, the access network device sends the identification information of the first DRB to the relay UE.

For example, the access network device may send configuration information of the first DRB to the relay UE. The configuration information of the first DRB includes identification information of the first DRB. The identification information of the first DRB may be an ID of the first DRB.

Accordingly, the relay UE receives the identification information of the first DRB from the access network device.

The first DRB may be obtained by mapping, by the access network device, the first service to the DRB according to Uu QoS requirement information of the first service.

S1204, the relay UE determines a first SLRB according to the PC5 QoS parameters of the first service.

In one example, the relay UE may map the first service to the SLRB according to the PC5 QoS parameter of the first service, resulting in the first SLRB. Alternatively, the relay UE may select, from the radio resource pool, an SLRB capable of matching the PC5 QoS parameter according to the PC5 QoS parameter of the first service, to obtain the first SLRB. The radio resource pool is preconfigured by access network equipment (such as a base station) or core network equipment (such as a PCF network element) for the relay UE, and comprises a plurality of SLRBs which can be selected by the relay UE.

S1205, the relay UE establishes a corresponding relation between the first DRB and the first SLRB according to the identification information of the first DRB and the determined first SLRB.

Alternatively, in another example, the first SLRB may be determined by the remote UE according to a PC5 QoS parameter of the first service. Specifically, the method may be based on the embodiment shown in fig. 12, and further replaces S1202 and S1204 with S1301 and S1302, and further replaces S1205 and S805 with S1303, as described in detail below.

S1301, the remote UE determines a first SLRB according to the PC5 QoS parameter of the first service.

In one example, the remote UE may map the first service to the SLRB according to the PC5 QoS parameters of the first service, resulting in the first SLRB. Alternatively, the remote UE may select, according to the PC5 QoS parameter of the first service, an SLRB capable of matching the PC5 QoS parameter from the radio resource pool, to obtain the first SLRB. The radio resource pool is preconfigured by access network equipment (such as a base station) or core network equipment (such as a PCF network element) for the remote UE, and comprises a plurality of SLRBs which can be selected by the remote UE.

S1302, the remote UE sends configuration information of the first SLRB to the relay UE.

Accordingly, the relay UE receives configuration information of the first SLRB from the remote UE.

Wherein, the configuration information of the first SLRB at least comprises one or more of the following: identification information of the first SLRB (e.g., ID of the first SLRB), configuration information of the RLC layer in the PC5 interface protocol stack, or configuration information of the MAC layer in the PC5 interface protocol stack.

S1303, the relay UE establishes a corresponding relation between the first DRB and the first SLRB according to the identification information of the first DRB and the configuration information of the first SLRB.

In the embodiment shown in fig. 12 or fig. 13, the determination is made by the access network device by determining a first communication link (i.e. a first DRB) for transmitting traffic data of a first traffic between the relay UE and the access network device, e.g. based on Uu QoS requirement information of the first traffic; the relay UE or the remote UE determines a second communication link (namely a first SLRB) for transmitting the service data of the first service between the remote UE and the relay UE according to the PC5 QoS parameters of the first service, so as to solve the problem that the transmission of the service data cannot be completed due to the fact that QoS parameters of a Uu interface communication link and a PC5 interface communication link are not matched in the conventional technology.

It is to be understood that the various aspects of the embodiments of the application may be used in any reasonable combination, and that the explanation or illustration of the various terms presented in the embodiments may be referred to or explained in the various embodiments without limitation.

It should also be understood that, in various embodiments of the present application, the sequence numbers of the foregoing processes do not mean the order of execution, and the order of execution of the processes should be determined by the functions and internal logic thereof, and should not constitute any limitation on the implementation process of the embodiments of the present application.

It will be appreciated that the relay UE, access network device, remote UE or other network device (e.g., PCF network element, SMF network element or AMF network element) may comprise hardware structures and/or software modules corresponding to performing the functions of any of the above embodiments. Those of skill in the art will readily appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is implemented as hardware or computer software driven hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

The embodiment of the application can divide the functional modules of equipment such as relay UE, access network equipment, remote UE or other network equipment (such as PCF network element, SMF network element or AMF network element), for example, each functional module can be divided corresponding to each function, and two or more functions can be integrated in one processing module. The integrated modules may be implemented in hardware or in software functional modules. It should be noted that, in the embodiment of the present application, the division of the modules is schematic, which is merely a logic function division, and other division manners may be implemented in actual implementation.

For example, in the case of dividing each functional module in an integrated manner, as shown in fig. 14, a structural block diagram of a UE according to an embodiment of the present application is provided. The UE may be a relay UE or a remote UE. The UE may include a transceiving unit 1410 and a processing unit 1420.

Wherein, when the UE is a relay UE, the transceiver unit 1410 is configured to support the relay UE to perform the steps S701, S804, S805, S806 (including S806-a and S806-b), S901, S1002, S1101, S1102, S1202, S1203, or S1302, and/or other processes for the techniques described herein. The processing unit 1420 is configured to support the relay UE to perform the steps S702, S902, S1003, S1004, S1103, S1104, S1204, S1205, or S1303 described above, and/or other procedures for the techniques described herein. When the UE is a remote UE, the transceiving unit 1410 is configured to support the remote UE to perform the steps S805, S806-a, S1201, S120, or S1302 described above, and/or other processes for the techniques described herein. The processing unit 1420 is configured to support the remote UE to perform step S1301 described above, and/or other processes for the techniques described herein.

Fig. 15 is a block diagram of a network device according to an embodiment of the present application. The network device may be the network device such as the access network device, the AMF network element, the PCF network element, or the SMF network element. The network device may include a transceiver unit 1510 and a processing unit 1520.

Where the network device is an access network device, the transceiver 1510 may support the access network device to perform steps S800-2, S804, S806-b, S901, S1002, S1101, S1102, or S1203 described above, and/or other processes for the techniques described herein. The processing unit 1520 may support the access network device to perform the steps S801, S802, S803, or S1001 described above, and/or other processes for the techniques described herein. When the network device is an AMF network element, the transceiver unit 1510 may support the AMF network element to perform the steps S800-1, S800-2, or S1201, and/or other procedures for the techniques described herein. Where the network device is a PCF network element, the transceiver 1510 may support the PCF network element to perform steps S800-1 or S1201 described above, and/or other procedures for the techniques described herein.

It should be noted that, the transceiver 1410 and the transceiver 1510 may include a radio frequency circuit. The UE or the network device may receive and transmit wireless signals through a radio frequency circuit. Typically, the radio frequency circuitry includes, but is not limited to, an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, and the like. In addition, the radio frequency circuitry may also communicate with other devices via wireless communications. The wireless communication may use any communication standard or protocol including, but not limited to, global system for mobile communications, general packet radio service, code division multiple access, wideband code division multiple access, long term evolution, email, short message service, and the like.

In an alternative, when data transmission is implemented using software, it may be implemented wholly or partly in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are fully or partially implemented. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in or transmitted from one computer-readable storage medium to another, for example, by wired (e.g., coaxial cable, optical fiber, digital Subscriber Line (DSL)), or wireless (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains an integration of one or more available media. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid State Disk (SSD)), etc.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied in hardware or in software instructions executed by a processor. The software instructions may be comprised of corresponding software modules that may be stored in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. In addition, the ASIC may be located in a probing device. It is of course also possible that the processor and the storage medium are present as separate components in the detection device.

From the foregoing description of the embodiments, it will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-described division of functional modules is illustrated, and in practical application, the above-described functional allocation may be implemented by different functional modules according to needs, i.e. the internal structure of the apparatus is divided into different functional modules to implement all or part of the functions described above.

In an alternative form, the present application provides a communication system that includes a remote UE, a relay UE, an access network device, an AMF unit, and a PCF unit. The communication system is used for realizing the data transmission method of the adjacent service in any possible implementation manner provided by the application.

In an alternative form, the application provides a chip system comprising a processor, a memory, the memory having computer program code stored therein; the computer program code, when executed by a processor, implements a method for data transmission of proximity services in any of the possible implementations provided by the application. The chip system may be formed of a chip or may include a chip and other discrete devices.

In the several embodiments provided by the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative, and the division of modules or units, for example, is merely a logical function division, and there may be additional divisions when actually implemented, for example, multiple units or components may be combined or integrated into another apparatus, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

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

In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a readable storage medium. Based on such understanding, the technical solution of the embodiments of the present application may be essentially or a part contributing to the prior art or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium, including several instructions for causing a device (may be a single-chip microcomputer, a chip or the like) or a processor (processor) to perform all or part of the steps of the method described in the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (Random Access Memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

The foregoing is merely illustrative of specific embodiments of the present application, and the scope of the present application is not limited thereto, but any changes or substitutions within the technical scope of the present application should be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method of proximity service data transmission, the method comprising:

the relay User Equipment (UE) acquires an identification of a first remote UE and a corresponding relation between a first communication link and a second communication link; the first communication link is used for transmitting data of a first service between the relay UE and access network equipment; the second communication link is configured to transmit data of the first service between the relay UE and the first remote UE;

the relay UE receives a downlink data packet of the first service through the first communication link, wherein the downlink data packet of the first service comprises an identifier of the first remote UE;

and the relay UE transmits the downlink data packet of the first service to the first remote UE through the second communication link according to the corresponding relation.

2. The method of claim 1, wherein the relay UE obtaining the correspondence between the first communication link and the second communication link comprises:

The relay UE receives the correspondence from the access network device.

3. The method according to claim 1 or 2, wherein the first communication link is further used for transmitting data of a second service between the relay UE and the access network device.

4. A method according to claim 3, characterized in that the method further comprises:

the relay UE receives an identification of a second remote UE from the access network equipment and a corresponding relation between the first communication link and a third communication link; the third communication link is for transmitting data of the second service between the relay UE and the second remote UE.

5. The method according to claim 4, wherein the method further comprises:

the relay UE receives a downlink data packet of the second service through the first communication link, wherein the downlink data packet of the second service comprises an identifier of the second remote UE;

and the relay UE transmits the downlink data packet of the second service to the second remote UE through the third communication link according to the corresponding relation between the first communication link and the third communication link.

6. The method according to any one of claims 1 to 5, wherein,

the first communication link is a Uu interface communication link, and the second communication link is a PC5 interface communication link.

7. A method of proximity service data transmission, the method comprising:

the access network equipment sends the identification of the first remote UE and the corresponding relation between the first communication link and the second communication link to the relay UE; the first communication link is used for transmitting data of a first service between the relay UE and the access network device; the second communication link is configured to transmit data of the first service between the relay UE and the first remote UE;

and the access network equipment sends the downlink data packet of the first service to the relay UE through the first communication link, wherein the downlink data packet of the first service comprises the identification of the first remote UE.

8. The method of claim 7, wherein the method further comprises:

the access network equipment receives a downlink data packet of the first service aiming at the first remote UE, and adds the identification of the first remote UE in the downlink data packet of the first service;

The access network device sends the downlink data packet of the first service added with the identification of the first remote UE to the relay UE through the first communication link.

9. The method according to claim 7 or 8, wherein before the access network device sends the identity of the first remote UE and the correspondence between the first communication link and the second communication link to the relay UE, the method further comprises:

the access network device determines that the second communication link is used to transmit data of the first service between the first remote UE and the relay UE.

10. The method according to any of claims 7-9, wherein the first communication link is further used for transmitting data of a second service between the relay UE and the access network device.

11. The method according to claim 10, wherein the method further comprises:

the access network equipment sends the identification of the second remote UE and the corresponding relation between the first communication link and the third communication link to the relay UE; the third communication link is for transmitting data of the second service between the relay UE and the second remote UE.

12. The method of claim 11, wherein the method further comprises:

and the access network equipment sends the downlink data packet of the second service to the relay UE through the first communication link, wherein the downlink data packet of the second service comprises the identification of the second remote UE.

13. The method according to any one of claims 7 to 12, wherein,

14. A relay UE, the relay UE comprising:

a memory for storing a computer program;

a processor for executing the computer program to implement the method of any of claims 1-6.

15. An access network device, the access network device comprising:

a memory for storing a computer program;

a processor for executing the computer program to implement the method of any of claims 7-13.

16. A communication system, the communication system comprising:

the relay UE of claim 14; and

the access network device of claim 15.

17. A computer readable storage medium, characterized in that the computer readable storage medium has stored thereon a computer program code which, when executed by a processing circuit, implements the method according to any of claims 1-6 or 7-13.

18. A chip system, comprising a processing circuit, a storage medium having computer program code stored therein; the computer program code implementing the method of any of claims 1-6 or 7-13 when executed by the processing circuit.

19. A communication system, the communication system comprising: a relay user equipment UE and a first remote UE;

the relay UE being configured to perform the method of any of claims 1-6;

the first remote UE is configured to receive a downlink data packet of a first service.