Sidelink relay communication methods, devices, equipment, and media

Abstract

This application proposes a sidelink relay communication method, apparatus, device, and medium. The sidelink relay communication method, applied to UE-to-network relay communication, includes: a relay UE receiving a data packet mapped by a source communication device onto a first bearer between the source communication device and the relay UE, wherein the source communication device includes a remote UE or a base station; the relay UE mapping the data packet onto a second bearer between the relay UE and a target communication device, and transmitting it to the target communication device, wherein the target communication device correspondingly includes a base station or a remote UE.

Description

Technical Field

[0001] This application relates to the field of communication technology, specifically to a sidelink relay communication method, apparatus, device, and medium. Background Technology

[0002] With the development of wireless multimedia services, people's demand for high data rates and user experience is increasing, thus placing higher demands on the system capacity and coverage of traditional cellular networks. Simultaneously, applications such as public safety, social networks, short-range data sharing, and local advertising are also driving the growing demand for Proximity Services (ProSe). To support a wider range of communication applications and services, sidelink (SL)-based relay communication can extend coverage and improve power consumption, such as in indoor relay communication, smart agriculture, smart factories, and public safety. However, due to significant differences between 5G / NR (New Radio) sidelink communication mechanisms and 4G LTE sidelink communication mechanisms, such as frame structure, QoS (Quality of Service) processing, bearer configuration, and establishment, LTE-based sidelink relay schemes are not suitable for 5G / NR systems. Therefore, how to implement sidelink relay communication suitable for 5G / NR systems is an urgent problem to be solved. Summary of the Invention

[0003] This application provides a sidelink relay communication method, apparatus, device, and medium suitable for 5G / NR systems.

[0004] In a first aspect, embodiments of this application provide a sidelink relay communication method applied to UE (User Equipment) to network relay communication, including:

[0005] The relay UE receives data packets that are mapped by the source communication device onto a first bearer between the source communication device and the relay UE, wherein the source communication device includes a remote UE or a base station;

[0006] The relay UE maps the data packet to a second bearer between the relay UE and the target communication device, and transmits it to the target communication device, wherein the target communication device includes a base station or a remote UE.

[0007] Secondly, embodiments of this application provide a sidelink relay communication method, applied to UE-to-network relay communication, including:

[0008] The relay UE indicates relay communication auxiliary information to the base station;

[0009] The relay UE receives relay communication configuration information sent by the base station and performs data transmission based on the relay communication configuration information.

[0010] Thirdly, embodiments of this application provide a sidelink relay communication method applied to UE-to-UE relay communication, including:

[0011] The relay UE receives a data packet sent by the source UE to the target UE, wherein the data packet is mapped by the source UE to a PC5 RLC bearer between the source UE and the relay UE and then sent to the relay UE;

[0012] The relay UE parses the data packet, identifies the target UE corresponding to the data packet, maps the data packet to the relay backhaul bearer between the relay UE and the target UE, and sends it to the target UE.

[0013] Fourthly, embodiments of this application provide a sidelink relay communication method applied to UE-to-UE relay communication, including:

[0014] The relay UE obtains the first relay communication configuration information sent by the base station;

[0015] The relay UE forwards data to the source UE and the target UE according to the first configuration information of the relay communication.

[0016] Fifthly, embodiments of this application provide a sidelink relay communication device configured in a communication device used for UE-to-network relay communication, comprising:

[0017] The first data receiving module is configured to receive data packets sent by a relay UE that are mapped by a source communication device onto a first bearer between the source communication device and the relay UE, wherein the source communication device includes a remote UE or a base station.

[0018] The first data forwarding module is configured to map the data packet to a second bearer between the relay UE and the target communication device, and transmit it to the target communication device, wherein the target communication device includes a base station or a remote UE.

[0019] Sixthly, embodiments of this application provide a sidelink relay communication device configured in a communication device used for UE-to-network relay communication, comprising:

[0020] The second information indication module is configured to indicate relay communication auxiliary information from the relay UE to the base station;

[0021] The second data transmission module is configured to receive relay communication configuration information sent by the base station and perform data transmission based on the relay communication configuration information.

[0022] In a seventh aspect, embodiments of this application provide a sidelink relay communication device configured in a communication device used for UE-to-UE relay communication, comprising:

[0023] The third data receiving module is configured to receive data packets sent by the source UE to the target UE by the relay UE, wherein the data packets are mapped by the source UE to a PC5 RLC bearer between the source UE and the relay UE and sent to the relay UE;

[0024] The third data forwarding module is configured to parse the data packet by the relay UE, identify the target UE corresponding to the data packet, map the data packet to the relay backhaul bearer between the relay UE and the target UE, and send it to the target UE.

[0025] Eighthly, embodiments of this application provide a sidelink relay communication device configured for use in UE-to-UE relay communication equipment, characterized in that it includes:

[0026] The fourth information acquisition module is configured to allow the relay UE to acquire the first configuration information for relay communication sent by the base station;

[0027] The fourth data forwarding module is configured to forward data between the source UE and the target UE based on the first configuration information of the relay communication.

[0028] Ninthly, embodiments of this application provide a communication device, including: one or more processors; a storage device for storing one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors implement the sidelink relay communication method applied to UE-to-network relay communication as described in the first or second aspect.

[0029] In a tenth aspect, embodiments of this application provide a communication device, comprising: one or more processors; a storage device for storing one or more programs; and when the one or more programs are executed by the one or more processors, causing the one or more processors to implement the sidelink relay communication method applied in UE-to-UE relay communication as described in the third or fourth aspect.

[0030] Eleventhly, embodiments of this application provide a storage medium storing a computer program that, when executed by a processor, implements the sidelink relay communication method as described in any embodiment of this application.

[0031] Further details regarding the above embodiments and other aspects of this application, as well as their implementations, are provided in the accompanying drawings, detailed description, and claims. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of a sidelink relay communication scheme;

[0033] Figure 2 A flowchart illustrating a sidelink relay communication method provided in this application;

[0034] Figure 3 A schematic diagram of the L2 UE-to-network relay control plane protocol stack provided in this application;

[0035] Figure 4 This application provides a schematic diagram of the L2 UE-to-Network relay user plane protocol stack.

[0036] Figure 5 A flowchart illustrating a sidelink relay communication method provided in this application;

[0037] Figure 6 A schematic diagram illustrating the process of establishing an RRC connection between a remote UE and a base station via a relay UE, as provided in this application;

[0038] Figure 7 A schematic diagram illustrating the process of establishing the L2 UE-to-network relay data forwarding bearer provided in this application;

[0039] Figure 8 Diagrams illustrating relay forwarding under different air interface standards provided in this application;

[0040] Figure 9 Diagrams illustrating relay forwarding under different air interface standards provided in this application;

[0041] Figure 10 A flowchart illustrating a sidelink relay communication method provided in this application;

[0042] Figure 11 This application provides a schematic diagram of the L2 UE-to-UE relay control plane protocol stack.

[0043] Figure 12 This application provides a schematic diagram of the L2 UE-to-UE relay user plane protocol stack.

[0044] Figure 13A schematic diagram of the multi-hop L2 UE-to-UE relay protocol stack provided in this application;

[0045] Figure 14 A flowchart illustrating a sidelink relay communication method provided in this application;

[0046] Figure 15 This application provides a schematic diagram of the L2 UE-to-UE relay bearer establishment process.

[0047] Figure 16 A schematic diagram of the structure of a sidelink relay communication device provided in this application;

[0048] Figure 17 A schematic diagram of the structure of a sidelink relay communication device provided in this application;

[0049] Figure 18 A schematic diagram of the structure of a sidelink relay communication device provided in this application;

[0050] Figure 19 A schematic diagram of the structure of a sidelink relay communication device provided in this application;

[0051] Figure 20 This is a schematic diagram of the structure of a communication device provided in this application. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be arbitrarily combined with each other.

[0053] Before describing the implementation methods provided in this application, we will first provide an exemplary explanation of the relevant knowledge of sidelink relay communication.

[0054] Traditional base station-centric cellular networks have significant limitations in supporting high data rates and proximity services. Against this backdrop, Device-to-Device (D2D) communication technology emerged. The application of D2D technology can alleviate the burden on cellular networks, reduce battery power consumption of user devices, increase data rates, and improve the robustness of network infrastructure, effectively meeting the requirements of high data rate services and proximity services. D2D technology is also known as Proximity Services (ProSe), or Sidelink (SL) communication. In this technology, the interface between devices is a PC5 interface (straight-through interface), and the interface between the device and the base station is a Uu interface (air interface).

[0055] To support a wider range of applications and services, sidelink-based relay communication can extend coverage and improve power consumption, such as in indoor relay communication, smart agriculture, smart factories, and public safety. Sidelink relay communication primarily has the following two application scenarios:

[0056] 1) UE-to-Network relay: UE relay transmission in areas with weak / no coverage, such as... Figure 1 Mode 1 allows UE1 with poor signal quality to communicate with the network through UE2, which has network coverage nearby. This helps operators expand coverage and increase capacity. UE2 is called UE-to-Network relay, and UE1 is called remote UE.

[0057] 2) UE-to-UE relay: In the event of an earthquake or emergency where the cellular network cannot function properly, or to extend the sidelink communication range, communication between devices is allowed via a relay UE, such as... Figure 1 In Mode 2, UE3 and UE4 communicate with each other via UE5 or a multi-hop relay UE. UE5 is called a UE-to-UE relay, i.e., a relay UE, while UE3 and UE4 are the source UE or the target UE, respectively.

[0058] LTE provides two UE-to-Network relay technology solutions: one based on the IP layer (Layer 3) and the other on the access layer (Layer 2). Layer 3 relay forwards data based on information such as the destination IP address / port number; Layer 2 relay routes and forwards control plane and user plane data at the access layer, enabling operators (i.e., core network elements and base stations) to more effectively manage remote devices (remote UEs).

[0059] The technical terms included in this application include, but are not limited to:

[0060] Radio Resource Control (RRC), Protocol Data Unit (PDU), Radio Link Control (RLC), Backhaul (BH), Sidelink (SL), PC5 Interface (Straight-through Interface), Uu Interface (Air Interface), Signal Radio Bearer (SRB), Data Radio Bearer (SRB), Packet Data Convergence Protocol (PDCP), Service Data Adaptation Protocol (SDAP), Quality of Service (QoS), Media Access Control (MAC), User Plane Function (UPF), 5G QoS Identifier (5QI), QoS Flow Identifier (QFI), Guaranteed Flow Bit Rate (GFBR), Maximum Flow Bit Rate. Rate (MFBR), Logical Channel ID (LCID), Cell-Radio Network Temporary Identifier (C-RNTI), Sidelink Radio Bearer (SLRB), Unacknowledged Mode (UM), Acknowledged Mode (AM), Access and Mobility Management Function (AMF), RadioAccess Network NG application layer protocol ID (RAN NGAP ID), Aggregate Maximum Bit Rate (AMBR), Per-Packet Priority (PPP), Operation Administration and Maintenance (OAdministration and Maintenance).OAM), PC5 QoS flow identifier (PFI), and 5QI on the PC5 interface (PC5 5QI, PQI).

[0061] In one exemplary implementation Figure 2 This application provides a flowchart illustrating a sidelink relay communication method. This method is applicable to both control plane and user plane data forwarding in NR systems. The method can be executed by the sidelink relay communication device provided in this application, which is used for UE-to-network relay communication. This sidelink relay communication device can be implemented in software and / or hardware and integrated into a communication device, which can be a Layer 2 UE-to-Network relay communication relay UE.

[0062] like Figure 2 As shown, this application provides a sidelink relay communication method applied to Layer 2 UE-to-Network relay communication, including:

[0063] S110, the relay UE receives a data packet that is mapped by the source communication device onto a first bearer between the source communication device and the relay UE, wherein the source communication device includes a remote UE or a base station.

[0064] S120. The relay UE maps the data packet to a second bearer between the relay UE and the target communication device and transmits it to the target communication device, wherein the target communication device includes a base station or a remote UE.

[0065] The data packets can be either control plane data packets or user plane data packets. When the source communication device is a remote UE, the target communication device is a base station; conversely, when the source communication device is a base station, the target communication device is a UE.

[0066] For L2 UE-to-Network relay, the remote UE can maintain an RRC connection with the base station through the relay UE. This means the base station can identify the remote UE, save its context, the network can page it, and the base station / core network maintains a PDU session for the remote UE. Essentially, on the air interface, data from the remote UE is transmitted to the base station via the PC5 interface SLRB between the remote UE and the relay UE, and the relay forwarding bearer between the relay UE and the base station. Then, it is still transmitted to the 5GC through the remote UE's PDU session. This requires consideration of data routing and bearer mapping issues.

[0067] In the above technical solution, the source communication device maps the data packet to the first bearer between the source communication device and the relay UE and sends it to the relay UE. After receiving the data packet, the relay UE maps the data packet to the second bearer between the relay UE and the target communication device and transmits it to the target communication device. This realizes relay data forwarding between the source communication device and the target communication device applicable to 5G / NR systems.

[0068] L2 UE-to-Network relay control plane protocol stack such as Figure 3 As shown, the user plane protocol stack is as follows: Figure 4 As shown, an adaptation layer can be introduced to implement L2 forwarding and routing functionality. The adaptation layer on the PC5 interface (shown in the dashed box in the figure) is optional, meaning that in some schemes described below, an adaptation layer is not required to implement L2 forwarding and routing functionality.

[0069] In one example, the source communication device is a remote UE, and the target communication device is a base station. That is, the L2 UE-to-Network relay communication data route is uplink, and the data includes control plane data and user plane data.

[0070] Furthermore, the relay UE receiving data packets transmitted by the source communication device and mapped onto the first bearer between the source communication device and the relay UE can specifically be as follows:

[0071] The relay UE receives data packets sent by the remote UE, wherein the data packets are mapped by the remote UE from the Uu bearer to the PC5 RLC bearer between the remote UE and the relay UE based on a set mapping relationship and transmitted to the relay UE;

[0072] The relay UE maps the data packet to a second bearer between the relay UE and the target communication device, and transmits it to the target communication device, which can be specifically as follows:

[0073] The relay UE identifies the Uu bearer of the remote UE to which the data packet belongs, and maps the data packet onto the relay bearer between the relay UE and the base station for transmission to the base station.

[0074] Setting the mapping relationship refers to the mapping relationship between the Uu bearer configured or pre-configured or pre-defined by the base station and the PC5 RLC bearer. That is, the remote UE maps data packets from the Uu bearer to the PC5 RLC bearer according to the mapping relationship between the Uu bearer configured or pre-configured or pre-defined by the base station.

[0075] Among them, PC5 RLC bearer is also known as PC5 BH bearer, SL BH bearer, or Access BH bearer; Uu bearer refers to Uu DRB / SRB; relay bearer, relay Uu backhaul bearer, and relay air interface bearer are all the same, referring to the bearer between relay UE and base station.

[0076] For example, the predefined mapping relationship between Uu bearers and PC5 RLC bearers can be such that the protocol defines UuSRB0 as mapping to the PC5 RLC bearer associated with the sidelink logical channel LCID0 (for example only, it can be LCID1 or others), Uu SRB1 as mapping to the PC5 RLC bearer associated with the sidelink logical channel LCID1, and so on.

[0077] Specifically, firstly, the Remote UE's higher layers generate data packets and, based on 5G Uu QoS processing rules and / or bearer configuration, map the data packets or Uu RRC signaling / messages to the corresponding Uu DRB / SRB PDCP entities, performing UuPDCP layer operations such as header compression, encryption, integrity protection, and packet encapsulation. Secondly, the Remote UE maps the Uu PDCP PDU to the PC5 RLC bearer between itself and the relay UE. Thirdly, based on the mapping relationship between the base station configuration or pre-configured or predefined Uu bearers and PC5 RLC bearers, the Remote UE maps the Uu PDCP PDU to the PC5 RLC bearer, performs RLC / MAC / PHY layer processing, and sends the data packets to the relay UE via sidelink resources.

[0078] The Relay UE receives and parses data packets sent by the remote UE, identifies the data packets as those that need to be forwarded to the base station, identifies the remote UE Uu bearer to which the data packets belong, and maps the data packets to be forwarded onto the relay air interface bearer between the UE and the base station for transmission to the base station.

[0079] After receiving data forwarded by the relay UE, the base station parses the data packets, identifies the corresponding remote UE and Uu bearer, and delivers the data packets to the receiving PDCP entity of the corresponding remote UE Uu bearer. If the received data is control plane signaling from the remote UE, the base station further delivers it to the RRC layer for processing; if the received data is user plane data from the remote UE, the base station further maps the data packets to the NG interface transmission tunnel of the corresponding remote UE's PDU session and sends them to the core network element (UPF).

[0080] In one example, the method by which a remote UE maps from a Uu bearer to a PC5 RLC bearer between the remote UE and the relay UE includes at least one of the following:

[0081] The remote UE maps Uu bearer data packets to corresponding PC5 RLC bearers;

[0082] The remote UE maps and / or delivers the Uu bearer data packets to the adaptation layer, which then processes them and maps them onto the PC5 RLC bearer.

[0083] If there is a one-to-one mapping between the remote UE's Uu SRB / DRB and the PC5 RLC bearer, then no adaptation layer is needed between the remote UE and the relay UE. If multiple Uu SRBs or DRBs of the remote UE can be mapped to the same PC5 RLC bearer, then the adaptation layer between the remote UE and the relay UE can indicate which Uu SRB / DRB of the remote UE the current data packet belongs to. This allows the relay UE to forward the data packet to the base station, and the base station to identify and deliver it to the receiving PDCP entity of the corresponding Uu SRB / DRB. Specifically, the header of the adaptation layer between the remote UE and the relay UE contains the remote UE's Uu bearer identifier / index.

[0084] In one example, the remote UE mapping and / or delivering Uu bearer data packets to the adaptation layer for processing includes: adding an adaptation layer header, wherein the adaptation layer header includes at least one of the following:

[0085] The remote UE's Uu bearer identifier or index, relay forwarding indication, the remote UE's Uu bearer priority, 5QI, QFI.

[0086] To enable the relay UE to distinguish between data destined for itself and data that needs to be forwarded after receiving a data packet, the following methods can be used:

[0087] Use dedicated PC5 RLC bearers for forwarding data, such as negotiated between remote UE and relay UE via PC5RRC signaling, to determine which PC5 RLC bearers or logical channels (PC5 RLC bearer identifiers or LCIDs) are dedicated to forwarding data, or to define which logical channels (such as all LCIDs between LCID x and LCID y) are dedicated to forwarding data.

[0088] The adaptation layer between the remote UE and the relay UE indicates whether the current data packet is data that terminates to the relay UE itself or data that needs to be forwarded. For example, the adaptation layer header may indicate whether the data is relayed by using 1 bit or a relay forwarding indication field.

[0089] The ordinary unicast connection between the Remote UE and the relay UE and the PC5 connection for relay forwarding are PC5 connections corresponding to different source and destination identifiers. The relay UE can distinguish them by the source and destination identifiers in the MAC subheader.

[0090] Optionally, in order for the relay UE to map the data to be forwarded to the relay air interface bearer after receiving it, the PC5 adaptation layer can indicate the 5QI or QoS configuration information of the Uu QoS flow to which the data packet belongs (such as 5QI, the priority (priority / PBR / PER) associated with 5QI, GFBR / MFBR, resource type, etc.) or the bearer priority or 5QI of the Uu SRB / DRB to which the data packet belongs.

[0091] In summary, if a PC5 / SL adaptation layer is introduced between a Remote UE and a relay UE, the PC5 / SL adaptation layer header may contain at least one of the following: the Uu bearer identifier or index of the remote UE, relay forwarding indication, remote UE Uu bearer priority, 5QI, GFBR / MFBR.

[0092] In one example, the relay UE identifies the Uu bearer of the remote UE to which the data packet belongs, including:

[0093] The relay UE identifies the Uu bearer of the remote UE to which the data packet belongs by obtaining a one-to-one mapping relationship between the Uu bearer of the remote UE obtained from the base station or a predefined one-to-one mapping relationship between the Uu bearer of the remote UE and the PC5 RLC bearer, or by the Uu bearer identifier or index of the remote UE contained in the adaptation layer packet header.

[0094] The Relay UE receives and parses data packets sent by the Remote UE. It identifies data packets that need to be forwarded to the base station through the PC5 RLC bearer / LCID used for forwarding data in the interaction with the Remote UE, or the relay forwarding indication in the adaptation layer header. Furthermore, the Relay UE can identify the Remote UE UuSRB / DRB to which the data packet belongs through the one-to-one mapping between the Remote UE Uu SRB / DRB and the PC5 RLC bearer, or through the Remote UE Uu bearer identifier or index included in the adaptation layer.

[0095] In one example, the method by which the relay UE maps the data packet to the relay payload between the relay UE and the base station for transmission to the base station includes at least one of the following:

[0096] The relay UE maps the data packets to the Uu RLC bearer associated with the relay UE Protocol Data Unit (PDU) session, which is dedicated to data forwarding, for transmission.

[0097] The relay UE maps the data packet to a relay Uu backhaul bearer dedicated to relay data forwarding and sends it.

[0098] When a relay UE maps the data packet to a dedicated relay Uu backhaul bearer for relay data forwarding, the relay Uu BH bearer does not have a corresponding PDU session or core network transmission tunnel. The relay Uu BH bearer can be a one-to-one mapping, meaning data from different remote UEs is sent through different relay Uu BH bearers, or a many-to-one mapping, meaning data packets with similar QoS from multiple remote UEs can be mapped to the same relay Uu BH bearer for transmission. The relay UE adaptation layer processes the data packets and maps them to the relay Uu BH bearer.

[0099] In one example, when the relay Uu BH bearer is a many-to-one mapping, the relay UE maps the data packet to the relay Uu backhaul bearer, including:

[0100] The relay UE adaptation layer adds a header to the data packet and maps it to the relay Uu backhaul bearer. The header includes at least one of the following information: remote UE identifier, remote UE Uu bearer identifier, PC5 RLC bearer identifier, logical channel identifier or logical channel priority associated with the PC5 RLC bearer, and remote UE Uu bearer priority. The above information is added so that the base station can identify which remote UE and which SRB / DRB the data packet forwarded by the relay UE is from.

[0101] In one example, the relay UE maps the data packet to the relay Uu backhaul bearer in at least one of the following ways:

[0102] The relay UE maps data packets to the relay Uu backhaul bearer based on the mapping relationship between the PC5 RLC bearer configured or pre-configured or pre-defined by the base station, such as mapping based on bearer identifier or mapping based on bearer / logical channel priority.

[0103] The logical channel priority of the relay UE based on PC5 RLC is mapped to the backhaul bearer of the relay Uu with the same logical channel priority;

[0104] The relay UE maps the priority of the remote UE Uu bearer contained in the received PC5 adaptation layer to the relay Uu backhaul bearer with the same bearer or logical channel priority.

[0105] The relay UE maps data packets to the relay Uu backhaul bearer based on the 5QI contained in the received PC5 adaptation layer packet header and the mapping relationship between the base station configured or pre-configured 5QI and the relay Uu backhaul bearer.

[0106] In one example, after the base station receives data forwarded by the relay UE, it performs packet parsing to identify the remote UE and Uu bearer corresponding to the packet. This identification can be based on the relay Uu BH bearer, which is dedicated to forwarding a specific Uu bearer data of the remote UE; or it can be based on the remote UE identifier, PC5 RLC bearer identifier / logical channel identifier, and the mapping relationship between the remote UE Uu bearer and the PC5 RLC bearer in the adaptation layer packet header; or it can be based on the remote UE identifier and the remote UE Uu bearer identifier in the adaptation layer packet header.

[0107] In one example, the source communication device is a base station, and the target communication device is a remote UE, that is, the L2 UE-to-Network relay communication data routing is downlink, and the data includes control plane data and user plane data.

[0108] Furthermore, the relay UE receiving data packets transmitted by the source communication device and mapped onto the first bearer between the source communication device and the relay UE can specifically be as follows:

[0109] The relay UE receives data packets sent by the base station, wherein the data packets are mapped by the base station from the Uu bearer of the remote UE to the relay bearer between the base station and the relay UE and then sent to the relay UE;

[0110] The relay UE maps the data packet to a second bearer between the relay UE and the target communication device, and transmits it to the target communication device, which can be specifically as follows:

[0111] The relay UE maps the data packet to a PC5 RLC bearer between the relay UE and the remote UE, and sends it to the remote UE.

[0112] Specifically, the base station receives downlink data sent to the remote UE by the UPF, maps the downlink remote UE data or the RRC signaling message generated by the base station for the remote UE to the remote UE Uu bearer, and maps the remote UE Uu bearer to the intermediate carryover between the remote UE and the relay UE before sending it to the relay UE. After receiving the data, the relay UE parses it, identifies the data packet as one that needs to be forwarded to the remote UE, maps it to the PC5 bearer, and sends it to the remote UE. The remote UE receives and parses the PC5 interface data, identifies the remote UE Uu bearer corresponding to the data packet, and submits it to the PDCPentity associated with the Uu bearer.

[0113] In one example, the method by which the base station maps the Uu bearer of the remote UE to the relay bearer between the base station and the relay UE includes at least one of the following:

[0114] The base station maps the remote UE Uu bearer data packet (PDCP PDU) to the relay Uu BH bearer dedicated to forwarding the Uu bearer data of the remote UE;

[0115] The base station maps the Uu bearer data packets (PDCP PDU) of the remote UE to the Uu RLC bearer associated with the relay UE PDU session, which is dedicated to data forwarding;

[0116] The base station delivers the Uu bearer data packet of the remote UE to the adaptation layer for processing, adds an adaptation layer header, and maps it to a dedicated relay Uu backhaul bearer for data forwarding. This relay Uu backhaul bearer does not have a corresponding PDU session or NG interface transmission tunnel. The adaptation layer header includes at least one of the following: remote UE identifier, remote UE Uu bearer identifier or index, remote UE Uu bearer priority, 5QI (5QI of the QoS flow corresponding to the data packet), QoS flow identifier QFI, PC5 RLC bearer identifier or logical channel identifier.

[0117] In one example, after receiving the data, the Relay UE parses it and can identify that the data needs to be forwarded to the remote UE based on the remote UE identification information in the dedicated forwarding bearer or adaptation layer header.

[0118] In one example, the method by which the relay UE maps the data packet to the PC5RLC bearer between the relay UE and the remote UE includes at least one of the following:

[0119] If the PC5 RLC bearer is a bidirectional bearer, then a reverse mapping is performed based on the mapping relationship between the uplink PC5 RLC bearer and the trunk Uu backhaul bearer;

[0120] Based on the mapping relationship between the base station configuration or pre-configuration or pre-defined relay Uu backhaul bearer and the PC5 RLC bearer, data packets (PDCP PDU) are mapped to the PC5 RLC bearer. The mapping relationship can be a bearer identifier mapping or a bearer / logical channel priority mapping.

[0121] Based on the bearer priority or logical channel priority of the Uu relay backhaul bearer, data packets (PDCP PDU) are mapped to PC5 RLC bearers with the same bearer or logical channel priority.

[0122] The relay UE maps data packets (PDCP PDUs) to PC5 RLC bearers based on the Uu bearer identifier, index, or priority information of the remote UE in the adaptation layer packet header, and the mapping relationship between the Uu bearer of the remote UE and the PC5 RLC bearer configured, pre-configured, or pre-defined by the base station. The mapping relationship can be a bearer identifier mapping or a bearer priority mapping.

[0123] The relay UE maps data packets (PDCP PDUs) to PC5 RLC bearers based on the 5QI or QFI in the adaptation layer packet header and the mapping relationship between the priority of 5QI / QFI and PC5 RLC bearers configured or pre-configured or pre-defined by the base station.

[0124] The relay UE maps data packets (PDCPPDU) to PC5 RLC bearers based on the PC5 RLC bearer identifier or logical channel identifier in the adaptation layer header; wherein, the aforementioned data packets (PDCP PDU) can be data packets with the adaptation layer header removed;

[0125] The relay UE submits the parsed Uu interface data packets to the PC5 interface adaptation layer for processing, adds an adaptation layer header, and maps them to the PC5 RLC bearer for transmission. The adaptation layer header includes at least one of the following: the remote UE's Uu bearer identifier or index, the remote UE's Uu bearer priority, 5QI, or QFI. When multiple Uu SRBs / DRBs of the remote UE can be mapped to the same relay Uu BH bearer / PC5 RLC bearer, the remote UE, upon receiving data from the PC5 RLC bearer, cannot distinguish which Uu SRB / DRB's corresponding PDCP entity to deliver the data to. This distinction can be made correctly using the information in the adaptation layer header. Optionally, the adaptation layer header includes a relay forwarding indicator to indicate whether the received data is relay data itself or downlink data that needs to be forwarded.

[0126] In one example, the Remote UE receives and parses PC5 interface data, and identifies the remote UE EUu bearer corresponding to the data packet in the following way:

[0127] Based on the mapping relationship between the remote UE Uu bearer and the PC5 RLC bearer (such as bearer / logical channel identifier mapping, or bearer / logical channel priority mapping) configured or pre-configured by the base station; or

[0128] Based on information in the PC5 interface adaptation layer header, such as the remote UE Uu bearer identifier / index or remote UE Uu bearer priority, the data packet is delivered to the corresponding remote UE Uu bearer; or based on 5QI or QFI in the adaptation layer header, and the mapping relationship between the remote UE Uu bearer and 5QI / QFI configured or pre-configured by the base station, the data packet is delivered to the corresponding remote UE Uu bearer.

[0129] The remote UE identifier in the aforementioned adaptation layer header is used by relay UEs and base stations to identify remote UEs. In one example, the remote UE identifier includes at least one of the following:

[0130] UE Layer 2 identifier, partial UE Layer 2 identifier, base station is the C-RNTI or local identifier configured for remote UE, relay UE is the local identifier configured for remote UE.

[0131] Among them, the UE layer 2 identifier, namely the remote UE L2 ID, is 24 bits long and can be completely contained in the adaptation layer header, but the air interface overhead is relatively large.

[0132] Partial UE Layer 2 identifier, i.e., the truncated part of the Remote UE L2 ID, such as extracting the lower m bits of the L2 ID to identify the remote UE, where m is any integer between 1 and 24;

[0133] The base station configures a C-RNTI or local identifier for the remote UE. This local identifier is unique under the relay UE, and the base station can identify the remote UE through the relay UE and this local identifier. If it is a C-RNTI, the relay UE can know the remote UE's C-RNTI, which may pose certain security issues. Specifically, after receiving the PC5 connection establishment request message sent by the remote UE, the relay UE instructs the base station to initiate relay communication, such as by instructing the base station to initiate relay communication through a sidelink UE Information message. The sidelink UE Information message contains at least one of the following: UE type is RelayUE, relay UE L2 ID, remote UE L2 ID, and the base station configures a C-RNTI or local identifier for the remote UE and sends it to the relay UE.

[0134] The Relay UE assigns a local identifier to the remote UE. This local identifier is unique within the relay UE, and the base station can identify the remote UE through the relay UE and this local identifier. The length of this local identifier is shorter than the L2 ID or C-RNTI, which saves air interface overhead. Specifically, after receiving the PC5 connection establishment request message from the remote UE, the Relay UE assigns a local identifier to the remote UE and carries this local identifier when instructing the base station to initiate relay communication, such as by instructing the base station to initiate relay communication through the sidelink UE Information message. The sidelink UE Information message contains at least one of the following: UE type is Relay UE, relay UE L2 ID, remote UE L2 ID, remote UE local identifier, and the base station configures relay communication resources for the relay UE.

[0135] In one exemplary implementation Figure 5This application provides a flowchart illustrating a sidelink relay communication method. This method is applicable to both control plane and user plane data forwarding in NR systems. The method can be executed by the sidelink relay communication device provided in this application, which is used for UE-to-network relay communication. This sidelink relay communication device can be implemented in software and / or hardware and integrated into a communication device, which can be a Layer 2 UE-to-Network relay communication relay UE.

[0136] like Figure 5 As shown, this application provides a sidelink relay communication method applied to Layer 2 UE-to-Network relay communication, including:

[0137] S210, The relay UE indicates relay communication auxiliary information to the base station.

[0138] Relay communication auxiliary information refers to information used by a relay UE to instruct a base station to perform relay communication. In one example, the relay communication auxiliary information includes at least one of the following: relay communication indication, relay UE indication, relay type, serving remote UE information, communication standard between the relay UE and the remote UE, and the PC5 communication standard supported by the relay UE. The relay UE indication indicates that the relay UE is a relay UE, the relay type indicates whether it is a UE-to-Network relay or a UE-to-UE relay, and the communication standard can be LTE or NR. For example, after receiving a Layer 2 connection establishment request from a remote UE, the relay UE sends a sidelink UE Information message (i.e., relay communication auxiliary information) to the base station, instructing the base station to perform relay communication and indicating the serving remote UE. The sidelink UE Information includes at least one of the following: a relay UE indication, a remote UE L2 ID, and a remote UE local identifier (assigned by the relay UE).

[0139] S220, the relay UE receives the relay communication configuration information sent by the base station and performs data transmission based on the relay communication configuration information.

[0140] After receiving relay communication auxiliary information from the relay UE, the base station configures the relay communication for the relay UE. Upon receiving the relay communication configuration information from the base station, the relay UE completes the communication configuration based on the configuration information and then forwards relay data. The relay communication configuration information can be bearer configuration information; the relay UE forwards relay data after completing the bearer configuration.

[0141] In the above technical solution, the relay UE instructs the base station to perform relay communication, and the base station configures the relay base station for relay communication so that the relay UE can perform relay data forwarding after completing the configuration based on the relay communication configuration information. This realizes relay data forwarding between the source communication device and the target communication device applicable to 5G / NR systems.

[0142] In one example, the relay communication configuration information includes at least one of the following: relay Uu backhaul bearer configuration, PC5 RLC bearer configuration, and bearer mapping relationship;

[0143] The relay Uu backhaul bearer configuration includes at least one of the following: signaling forwarding bearer indication, data forwarding bearer indication, bearer identifier, RLC mode, RLC configuration, logical channel identifier, logical channel priority, logical channel group identifier, and logical channel related configuration.

[0144] PC5 RLC bearers can be divided into bidirectional PC5 RLC bearers and unidirectional PC5 RLC bearers. The unidirectional PC5 RLC bearer configuration includes relevant parameters for sidelink bearer transmission or reception. The bidirectional PC5 RLC bearer configuration includes at least one of the following: RLC acknowledged mode or unacknowledged mode, and other relevant configuration information for RLC and logical channels.

[0145] The bearer mapping relationship includes at least one of the following: a mapping of bearer or logical channel identifiers between the Uu backhaul bearer and the PC5 RLC bearer; a mapping of bearer or logical channel priority between the Uu backhaul bearer and the PC5 RLC bearer; a mapping relationship between the Uu bearer of the remote UE and the PC5 RLC bearer; and a mapping relationship between 5QI or QFI and the PC5 RLC bearer or logical channel priority.

[0146] Optionally, the base station configures a PC5 RLC bearer for the relay UE. The PC5 RLC bearer is divided into a bidirectional PC5 RLC bearer and a unidirectional PC5 RLC bearer. The unidirectional PC5 RLC bearer can be further divided into an uplink PC5 RLC bearer (sent by the remote UE and received by the relay UE) and a downlink PC5 RLC bearer (sent by the relay UE and received by the remote UE). The configuration information of the uplink PC5 RLC bearer only includes SLRB receiving-related parameters, such as RLC SN size and logical channel identifier. The configuration information of the downlink PC5 RLC bearer includes the parameters required for SLRB transmission. The configuration information of the bidirectional PC5 RLC bearer includes RLC AM mode or UM mode, and other RLC and logical channel-related configuration information.

[0147] Optionally, the base station is configured with a mapping relationship between the relay BH bearer and the PC5 RLC bearer, which may further include a mapping relationship between the relay BH bearer and the bidirectional PC5 RLC bearer, a mapping relationship between the relay BH bearer and the downlink PC5 RLC bearer, and a mapping relationship between the uplink PC5 RLC bearer and the relay BH bearer.

[0148] It is worth noting that even without configuring PC5 RLC bearers, it is possible to configure a mapping relationship between trunk Uu backhaul bearers and PC5 RLC bearers. In other words, the mapping relationship between trunk Uu backhaul bearers and PC5 RLC bearers is unrelated to the configuration of trunk Uu backhaul bearers and PC5 RLC bearers.

[0149] Furthermore, the relay UE forwards the remote communication configuration information configured by the base station for the remote UE;

[0150] The remote communication configuration information includes at least one of the following: Uu bearer configuration, PC5 RLC bearer configuration, and mapping relationship between Uu bearer and PC5 RLC bearer.

[0151] The Uu bearer configuration includes at least one of the following: bearer identifier, mapping from QFI or 5QI to Uu bearer, whether to carry the Service Data Adaptation Protocol (SDAP) header, and PDCP configuration;

[0152] The PC5 RLC bearer is divided into bidirectional PC5 RLC bearer and unidirectional PC5 RLC bearer. The unidirectional PC5 RLC bearer configuration includes relevant parameters for sidelink bearer transmission or reception. The bidirectional PC5 RLC bearer configuration includes at least one of the following: RLC acknowledged mode or unacknowledged mode, and other relevant configuration information for RLC and logical channels.

[0153] The mapping relationship between the Uu bearer and the PC5 RLC bearer includes at least one of the following: bearer or logical channel identifier mapping, bearer / logical channel priority mapping.

[0154] Optionally, the base station configures a PC5 RLC bearer for the remote UE. The PC5 RLC bearer is divided into a bidirectional PC5 RLC bearer and a unidirectional PC5 RLC bearer. The unidirectional PC5 RLC bearer can be further divided into an uplink PC5 RLC bearer (transmitted by the remote UE and received by the relay UE) and a downlink PC5 RLC bearer (transmitted by the relay UE and received by the remote UE). The configuration information of the uplink PC5 RLC bearer includes the relevant parameters required for SLRB transmission. The configuration information of the downlink PC5 RLC bearer includes the relevant parameters for SLRB reception, such as RLC SN size and logical channel identifier. The configuration information of the bidirectional PC5 RLC bearer includes: RLC AM mode or UM mode, and other RLC and logical channel related configuration information.

[0155] Optionally, the mapping relationship between Uu bearer and PC5 RLC bearer includes: the mapping relationship between Uu bearer and bidirectional PC5 RLC bearer, the mapping relationship between Uu bearer and uplink PC5 RLC bearer, and the mapping relationship between downlink PC5 RLC bearer and Uu bearer.

[0156] It is worth noting that even without configuring PC5 RLC bearer, it is possible to configure a mapping relationship between Uu bearer and PC5 RLC bearer. In other words, the mapping relationship between Uu bearer and PC5 RLC bearer is unrelated to the configuration of Uu bearer and PC5 RLC bearer.

[0157] Furthermore, after the relay UE indicates relay communication assistance information to the base station, the base station indicates or updates the information of the UE and the remote UE to the AMF entity, including at least one of the following:

[0158] Remote UE Layer 2 identifier, Remote UE Radio Access Network NG Application Protocol ID (RAN NGAP ID), Relay UE Layer 2 identifier, Relay UE RAN NGAP ID.

[0159] In one specific embodiment, for an RRC connected UE performing SL communication, the base station configures the SL bearer for the UE through RRC dedicated signaling; an RRC idle / inactive UE establishes the SL bearer based on the SL bearer configuration in the system message; and a UE without coverage establishes the SL bearer based on the SL bearer configuration in the pre-configured information.

[0160] Assuming UE1 is a remote UE with no coverage, locate UE2 (relay UE) within coverage area and perform signaling and data forwarding between UE1 and the network. Figure 6 As shown, after the remote UE discovers the relay UE, it establishes a Layer 2 connection (L2 link / PC5-S link) with the relay UE, and forwards signaling through the relay UE to establish an RRC connection with the base station. The base station can then configure the SL bearer for the remote UE using dedicated RRC signaling. Specifically:

[0161] After receiving the Layer 2 connection establishment request from the remote UE, the relay UE sends a sidelinkUEInformation message to the base station, instructing the base station to conduct relay communication and instructing the remote UE to provide service. That is, the sidelinkUEInformation contains at least one of the following: as a relay UE indication, the remote UE L2 ID, and the remote UE local identifier (assigned by the relay UE).

[0162] The base station configures a relay BH bearer for the relay UE to forward signaling from the remote UE. The relay BH bearer contains at least one of the following information: signaling forwarding bearer indication, bearer identifier / index, RLC AM mode, maximum retransmission count, polling-related configuration, logical channel identifier, logical channel priority, and logical channel group identifier. Alternatively, if one or more default signaling forwarding bearers are defined specifically for forwarding signaling from the remote UE, then no bearer configuration is required from the base station.

[0163] The relay UE establishes a relay BH bearer (control plane) according to the base station configuration and sends an RRC reconfiguration completion message to the base station. At the same time, the relay UE replies with a Layer 2 connection establishment response message to the remote UE.

[0164] The remote UE generates an RRC connection establishment request message and maps it to the defined default PC5 RLC bearer, then sends it to the relay UE. The relay UE then processes the request message according to the specified parameters. Figure 3 and Figure 4The protocol stack shown processes data packets and sends them to the base station via the relay BH bearer. The base station generates an RRC connection establishment message for the remote UE and maps it to the relay BH bearer before sending it to the relay UE. The relay UE then forwards the message to the remote UE via the PC5RLC bearer. The remote UE replies with an RRC connection establishment complete message to the base station and executes the registration process.

[0165] Optionally, when the base station sends an Initial UE message about the remote UE to the AMF (for remote UE), it indicates the relay UE information connected to the remote UE, including at least one of the following: relay UE L2ID, relay UE RAN NGAP ID.

[0166] Optionally, the base station indicates the newly accessed remote UE information to the relay UE's AMF, including at least one of the following: remote UE L2 ID, remote UE RAN NGAP ID. This information can be sent via NG interface UE-associated messages, such as UE context setup / modification response, uplink NAS transport, etc.

[0167] To support data forwarding for remote UEs, Relay UEs can use the following two methods:

[0168] One approach involves establishing a dedicated PDU session for data forwarding between the relay UE and the network. This session includes a Uu-interface relay BH bearer and an NG-U tunnel. However, the relay UE's NG-U tunnel is not used; instead, the NG-U tunnel associated with the remote UE's PDU session is used. Specifically, the base station and core network maintain the remote UE's PDU session. When uplink remote UE data arrives at the base station, the base station sends it to the remote UE's UPF via the NG-U tunnel associated with the remote UE's PDU session. Downlink remote UE data is sent to the base station via the NG-U tunnel associated with the remote UE's PDU session, and then the base station forwards it to the relay UE. Therefore, the dedicated NG-U tunnel associated with the relay UE's PDU session for data forwarding is essentially useless and its necessity is minimal.

[0169] Another option is to establish only the Uu interface relay BH bearer, without establishing a complete PDU session for data forwarding, which means there is no need to maintain the associated NG-U tunnel.

[0170] Figure 7 The diagram illustrates the air interface data forwarding bearer establishment process when a relay UE forwards data to a remote UE. After the remote UE establishes an RRC connection with the base station and registers with the core network through the relay UE, it initiates the PDU session establishment process when the remote UE needs to send data or when the network triggers the UE to initiate PDU session establishment. The 5GC provides the base station with QoS information related to PDU session establishment (such as PDU session AMBR, QoS flow level, and QoS parameters). The base station configures the remote UE data bearer and the relay UE air interface data forwarding bearer based on the QoS information provided by the 5GC.

[0171] The base station configures an air interface data forwarding bearer (relay BH bearer / relay RLC bearer) for the relay UE. The air interface data forwarding bearer configuration includes at least one of the following: data forwarding bearer indication, bearer identifier, RLC mode, logical channel identifier, logical channel group identifier, logical channel priority, priority guaranteed bit rate, bucket size duration, and RLC related configuration.

[0172] Optionally, the base station configures a PC5 RLC bearer for the relay UE. The PC5 RLC bearer is divided into a bidirectional PC5 RLC bearer and a unidirectional PC5 RLC bearer. The unidirectional PC5 RLC bearer can be further divided into an uplink PC5 RLC bearer (sent by the remote UE and received by the relay UE) and a downlink PC5 RLC bearer (sent by the relay UE and received by the remote UE). The configuration information of the uplink PC5 RLC bearer only includes SLRB receiving-related parameters, such as RLC SN size and logical channel identifier. The configuration information of the downlink PC5 RLC bearer includes the relevant parameters required for SLRB transmission. The configuration information of the bidirectional PC5 RLC bearer includes: RLC AM mode or UM mode, and other RLC and logical channel-related configuration information.

[0173] Optionally, the base station configuration of the mapping relationship between the relay BH bearer and the PC5 RLC bearer may further include the mapping relationship between the relay BH bearer and the bidirectional PC5 RLC bearer, the mapping relationship between the relay BH bearer and the downlink PC5 RLC bearer, and the mapping relationship between the uplink PC5 RLC bearer and the relay BH bearer. The mapping relationship between the relay BH bearer and the PC5 RLC bearer includes at least one of the following: the mapping of the bearer or logical channel identifier between the relay Uu backhaul bearer and the PC5 RLC bearer; the mapping of the bearer or logical channel priority between the relay Uu backhaul bearer and the PC5 RLC bearer; the mapping relationship between the Uu bearer of the remote UE and the PC5 RLC bearer; and the mapping relationship between 5QI or QFI and the PC5 RLC bearer or logical channel priority.

[0174] Optionally, the base station configures the mapping relationship between 5QI / QFI and the relay BH bearer. The relay UE maps uplink data to the relay BH bearer based on the 5QI / QFI in the adaptation layer header. Alternatively, the base station configures the mapping relationship between 5QI / QFI and the PC5RLC bearer. The relay UE maps downlink data packets to the PC5RLC bearer and sends them to the remote UE based on the 5QI / QFI in the adaptation layer header. The above configuration information sent by the base station to the relay UE is transmitted via an RRC reconfiguration message. The relay UE establishes the relay BH bearer based on the base station configuration and sends a response message to the base station.

[0175] The base station configures the Uu DRB and the mapping relationship between the Uu DRB and the PC5 RLC bearer for the remote UE. The Remote UEUu DRB configuration includes at least one of the following: bearer identifier, mapping of QoS flow / QFI / 5QI to DRB, whether to carry SDAP packet header, and PDCP configuration.

[0176] Optionally, the base station configures a PC5 RLC bearer for the remote UE. The PC5 RLC bearer is divided into a bidirectional PC5 RLC bearer and a unidirectional PC5 RLC bearer. The unidirectional PC5 RLC bearer can be further divided into an uplink PC5 RLC bearer (transmitted by the remote UE and received by the relay UE) and a downlink PC5 RLC bearer (transmitted by the relay UE and received by the remote UE). The configuration information of the uplink PC5 RLC bearer includes the relevant parameters required for SLRB transmission. The configuration information of the downlink PC5 RLC bearer includes the relevant parameters for SLRB reception, such as RLC SN size and logical channel identifier. The configuration information of the bidirectional PC5 RLC bearer includes: RLC AM mode or UM mode, and other RLC and logical channel related configuration information.

[0177] The mapping relationship between Uu DRB and PC5 RLC bearer includes: mapping relationship between Uu DRB and bidirectional PC5 RLC bearer, mapping relationship between Uu DRB and uplink PC5 RLC bearer, and mapping relationship between downlink PC5 RLC bearer and Uu DRB. The mapping relationship between Uu DRB and PC5 RLC bearer includes at least one of the following: bearer / logical channel identifier mapping, and bearer / logical channel priority mapping. The above configuration information sent by the base station to the remote UE is sent via RRC reconfiguration message and forwarded by the relay UE to the remote UE. The remote UE establishes Uu DRB (SDAP entity and PDCP entity) and PC5 RLC bearer based on the base station configuration and sends a configuration completion message to the base station.

[0178] It is worth noting that, Figure 7Steps 6-7 and 8-9 are not limited in time order. If the base station uniformly configures the PC5 RLC bearer (including logical channel identifier) ​​for both the relay UE and the remote UE, then the remote UE and the relay UE do not need to exchange PC5 RLC bearer configurations again. If it is not uniformly configured by the base station, then the remote UE and the relay UE still need to exchange PC5 RLC bearer configurations to ensure correct bidirectional transmission and reception of PC5 interface data.

[0179] Furthermore, the relay UE and the remote UE use the first communication standard, the relay UE and the base station use the second communication standard, and after the remote UE establishes an RRC connection with the base station through the relay UE, the remote UE and the base station use the second communication standard. For L2 relay, there are cases where the first and second communication standards are different.

[0180] In one example, the first communication standard is LTE, the second communication standard is NR, the remote UE's Uu bearer is an NR Uu bearer, the PC5 RLC bearer is an LTE PC5 RLC bearer, and the relay Uu backhaul bearer is an NR Uu backhaul bearer. That is, the remote UE (UE1) communicates with the relay UE via LTE PC5, while the relay UE's base station is an NR base station. The relay UE communicates with the base station via NR Uu, and the remote UE connects to this NR base station through the relay UE. Figure 8 As shown.

[0181] In one example, the mapping relationship between the remote UE NR Uu bearer and the LTE PC5 RLC bearer includes at least one of the following:

[0182] The mapping relationship between 5QI or QFI and PPPP (Packet Priority for Near Range Communication), the mapping relationship between priority and PPPP in 5QI, the mapping relationship between Uu bearer QoS and PPPP, and the mapping relationship between Uu bearer identifier or priority and PPPP.

[0183] In other words, the mapping relationship between NR Uu DRB and LTE PC5 BH bearer needs to be considered at the Remote UE level. This mapping relationship can be configured with any of the following: mapping between 5QI / QFI and PPP, mapping between priority level in 5QI and PPP, mapping between Uu DRB QoS and PPP, and mapping between Uu DRB identifier or priority and PPP. Here, Uu DRBQoS refers to DRB level QoS parameters, such as 5QI, GFBR / MFBR, AMBR, etc.

[0184] The above mapping relationship can be configured by the base station, or it can be pre-configured, or it can be configured by the ProSe or V2X control function of the proximity service, or it can be configured by OAM, or it can be defined by the protocol.

[0185] In one example, the bearer mapping relationship obtained by the relay UE includes at least one of the following: relay data forwarding is implemented according to one of the following mapping relationships: mapping relationship between relay Uu backhaul bearer or logical channel priority and PPPP, mapping relationship between remote UE's Uu bearer and relay Uu backhaul bearer, mapping relationship between 5QI or QFI and relay Uu backhaul bearer, and mapping relationship between remote UE NR Uu bearer and LTE PC5 RLC bearer. That is, in order to support relay UE data forwarding, any of the following mapping relationships can be configured: mapping relationship between relay BH bearer bearer / logical channel priority and PPPP, mapping relationship between remote UE UuDRB and relay BH bearer, mapping relationship between 5QI or QFI and relay Uu backhaul bearer, and mapping relationship between remote UE NRUu bearer and LTE PC5 RLC bearer. This mapping relationship can be configured by the base station, or pre-configured, or configured by ProSe or V2X control functions, or configured by OAM, or defined by the protocol. Optionally, the relay UE obtains the mapping relationship between the remote UE's NR Uu DRB and the LTE PC5 bearer, which can be configured or pre-configured by the base station, or configured by OAM or defined by the protocol.

[0186] In one example, the second communication standard is LTE, the first communication standard is NR, the remote UE's Uu bearer is an LTE Uu bearer, the PC5 RLC bearer is an NR PC5 RLC bearer, and the relay Uu backhaul bearer is an LTE Uu backhaul bearer. That is, as shown... Figure 9 As shown, UE1 is connected to relay UE via NR PC5. Relay UE is connected to LTE base station. Relay UE is connected to base station via LTE Uu. UE1 is connected to LTE base station via relay UE. UE1 Uu is LTE Uu.

[0187] In one example, the mapping relationship between the remote UE LTE Uu bearer and the NR PC5 RLC bearer includes at least one of the following: the mapping relationship between QCI and PQI, the mapping relationship between Uu bearer identifier or priority or QCI and PC5 RLC bearer logical channel priority, and the mapping relationship between Uu bearer identifier and PC5 RLC bearer logical channel identifier.

[0188] In other words, the Remote UE needs to consider the mapping relationship between the LTE Uu DRB and the NR PC5 BH bearer. Any of the following mapping relationships can be configured: the mapping relationship between QCI and PQI, the mapping relationship between the Uu bearer identifier or priority, or the mapping relationship between QCI and the PC5 RLC bearer logical channel priority, and the mapping relationship between the Uu bearer identifier and the PC5 RLC bearer logical channel identifier. These mapping relationships can be configured by the base station, pre-configured, configured by the Proximity Service (ProSe) or V2X control function, configured by OAM, or defined by the protocol.

[0189] In one example, the bearer mapping relationship obtained by the relay UE includes at least one of the following:

[0190] The mapping relationships between QCI and PQI, PC5 RLC bearer logical channel priority and relay Uu backhaul bearer logical channel priority, remote UE Uu bearer and relay Uu backhaul bearer, QCI and PC5 RLC bearer logical channel priority, PQI and relay Uu backhaul bearer logical channel priority, and remote UE LTE Uu bearer and NR PC5 RLC bearer.

[0191] In other words, to support relay UE data forwarding, the following arbitrary mapping relationships can be configured: the mapping relationship between QCI and PQI, the mapping relationship between PC5 BH bearer logical channel priority and relay BH bearer logical channel priority, the mapping relationship between remote UE Uu DRB and relay BH bearer, the mapping relationship between QCI and PC5 BH bearer logical channel priority, the mapping relationship between PQI and relay BH bearer logical channel priority, and the mapping relationship between remote UE LTE Uu bearer and NRPC5 RLC bearer. These mapping relationships can be configured by the base station, pre-configured, configured by ProSe or V2X control functions, configured by OAM, or defined by the protocol. Optionally, the relay UE obtaining the mapping relationship between the remote UE's LTE Uu DRB and NR PC5 BH bearer can be configured by the base station, pre-configured, configured by OAM, or defined by the protocol.

[0192] In one exemplary implementation Figure 10This application provides a flowchart illustrating a sidelink relay communication method. This method is applicable to both control plane and user plane data forwarding in NR systems. The method can be executed by the sidelink relay communication device provided in this application for UE-to-UE relay communication. This sidelink relay communication device can be implemented in software and / or hardware and integrated into a communication device, which can be a relay UE for Layer 2 UE-to-UE relay communication.

[0193] like Figure 10 As shown, this application provides a sidelink relay communication method applied to Layer 2 UE-to-UE relay communication, including:

[0194] S310. The relay UE receives a data packet sent by the source UE to the target UE, wherein the data packet is mapped by the source UE to a PC5 RLC bearer between the source UE and the relay UE and sent to the relay UE.

[0195] S320. The relay UE parses the data packet, identifies the target UE corresponding to the data packet, maps the data packet to the relay backhaul bearer between the relay UE and the target UE, and sends it to the target UE.

[0196] The source UE and the target UE forward data through a relay UE. For L2 UE-to-UE relay, the source UE and the target UE can establish a unicast connection (L2 link / PC5-S link / unicast link establishment) through the relay UE, and perform PC5 RRC signaling interaction, and maintain end-to-end PDCP.

[0197] In the above technical solution, the source UE maps the data packet to the PC5RLC bearer between the source UE and the relay UE and sends it to the relay UE. The relay UE receives and parses the data packet, identifies the target UE corresponding to the data packet, and maps the data packet to the relay backhaul bearer between the relay UE and the target UE and sends it to the target UE. This realizes relay data forwarding between the source communication device and the target communication device applicable to 5G / NR system.

[0198] Considering that a relay UE may simultaneously serve multiple remote UE pairs, the sending UE needs to instruct the target remote UE when sending data to the relay UE; the relay UE needs to instruct the source sending remote UE when forwarding data to the target remote UE; and the receiving UE / target UE needs to be able to identify which SLRB corresponds to the data received from the PC5 BH bearer and deliver it to the corresponding PDCP entity. Therefore, an adaptation layer is needed for data routing between the source UE and the relay UE and / or between the relay UE and the target UE. The L2UE-to-UE relay control plane protocol stack is as follows: Figure 11 As shown, the user plane protocol stack is as follows: Figure 12 As shown.

[0199] Assuming UE1 is the source UE and UE3 is the destination UE, the connection between UE1 and the relay UE is called the access BH, and the connection between the relay UE and UE3 is called the relay BH. The control plane and user plane data routing processes are as follows:

[0200] Signaling or data with the same / similar signaling priority or similar QoS forwarded by UE1 to different target UEs via relay UE can be mapped to the same access BH bearer and sent to the relay UE; signaling or data with the same / similar signaling priority or similar QoS from different remote UEs and sent to the same target UE via relay UE can be mapped to the same relay BH bearer and sent to the target UE.

[0201] For control plane data, UE1 generates PC5-S / PC5 RRC signaling messages for the source-target UE pair {UE1, UE3} and maps the signaling messages to the PDCP entity of the corresponding source-target UE pair's SL SRB based on the bearer configuration, performing PDCP layer operations such as header compression, encryption, integrity protection, and packet encapsulation. For user plane data, the higher layer of UE1 performs QoS processing on the data between the source-target UE pair {UE1, UE3}, obtaining a QoS flow through QoS rules, and submitting the QoS flow data to the SDAP entity of the corresponding source-target UE pair at the AS layer. The SDAP layer maps the data packets to the PDCP entity of the corresponding SL DRB based on the base station configuration or pre-configured SL DRB configuration and the QoS flow to SL DRB mapping relationship, performing PDCP layer operations such as header compression, encryption, integrity protection, and packet encapsulation.

[0202] In one example, before the data packet is mapped to a PC5 RLC bearer by the source UE, the process further includes: the data packet being submitted by the source UE to the adaptation layer for processing; wherein, the adaptation layer processing includes:

[0203] Add an adaptation layer header, wherein the adaptation layer header includes at least one of the following: target UE identifier, source UE identifier, sidelink bearer identifier, signaling bearer priority, PQI or PFI or 5QI or QFI.

[0204] The adaptation layer header refers to the adaptation layer header added by the source UE adaptation layer to the data packet. If the SL SRB for UE1's PC5-S / PC5-RRC message transmission or the SL DRB for data transmission has a one-to-one mapping with the access BH bearer, then the adaptation layer header may only carry the target UE identifier; if the SL SRB for UE1's PC5-S / PC5-RRC message transmission or the SL DRB for data transmission has a many-to-one mapping with the access BH bearer (multiple SL SRBs / DRBs can be mapped to the same access BH bearer), then the adaptation layer header carries the target UE identifier and the SL SRB / DRB identifier; optionally, the adaptation layer header carries the signaling bearer priority or the PQI / PFI / 5QI / QFI corresponding to the data packet, which can be used for relay UE to perform relay BHbearer mapping.

[0205] In one example, before the relay UE maps the data packet to the relay backhaul bearer between the relay UE and the target UE, the method further includes:

[0206] The relay UE processes the data packet through the adaptation layer; wherein the adaptation layer processing includes adding an adaptation layer header, wherein the adaptation layer header includes at least one of the following: source UE identifier, target UE identifier, sidelink bearer identifier, PC5 RLC bearer identifier or associated logical channel identifier, and sidelink bearer priority.

[0207] The adaptation layer header refers to the adaptation layer header added to the data packet by the relay UE adaptation layer.

[0208] Specifically, UE1 submits the SL PDCP PDU to the adaptation layer for processing. The encapsulated adaptation layer PDU is mapped to the access BH bearer (also known as the PC5 / SL backhaul / RLC bearer) between UE1 and the relay UE. After processing by RLC / MAC / PHY, it is sent to the relay UE. The relay UE receives the data packet sent by UE1 and parses it to the adaptation layer. It identifies the target UE through the information in the adaptation layer header and identifies the corresponding SL SRB / DRB of the data packet. Then, the parsed data packet is reprocessed by the adaptation layer, an adaptation layer header is added, and the encapsulated adaptation layer PDU is mapped to the relay BH bearer between UE1 and the target UE before being sent to the target UE. After receiving the data packet, the target UE parses it, identifies the source UE and SL bearer (SL SRB / DRB) corresponding to the data packet, and delivers the data packet to the receiving PDCP entity of the SL bearer of the corresponding source target UE pair. If the received data packet is control plane signaling sent by the source UE, the target UE further delivers it to the RRC layer / PC5-S for processing. If the received data packet is user plane data of the source UE, the target UE further delivers the data packet to the SDAP layer and application layer.

[0209] Optionally, the source transmitting UE maps the encapsulated adaptation layer PDU to the access BH bearer between the relay UE based on the protocol-defined or base station-configured or pre-configured mapping relationship between SL SRB / DRB and access BH bearer, or the mapping relationship between SL SRB / DRB and LCID (LCID associated access BH bearer). For example, SL SRB0 is mapped to the access BH bearer associated with LCID1, SL SRB1 is mapped to the access BH bearer associated with LCID2, and so on.

[0210] In one example, the relay UE identifies the target UE corresponding to the data packet, including:

[0211] The relay UE identifies the sidelink bearer of the target UE corresponding to the data packet, wherein the relay UE identifies the sidelink bearer of the target UE corresponding to the data packet in at least one of the following ways:

[0212] Identification is achieved through the sidelink bearer identifier in the adapter layer header;

[0213] Identification is achieved through the mapping relationship between the sidelink bearer defined by the protocol, or configured or pre-configured by the base station, and the PC5 RLC bearer or the LCID;

[0214] The source UE identifies the relay UE by informing it of the mapping relationship between the sidelink bearer and the PC5 RLC bearer or the LCID based on PC5 RRC signaling.

[0215] Specifically, UE1 notifies the relay UE of the mapping relationship between SL SRB / DRB and access BH bearer / LCID via PC5 RRC signaling; specifically, the PC5 RRC configuration information sent by UE1 to the relay UE includes at least one of the following: source UE identifier, target UE identifier, and access BH bearer / logical channel identifier associated with each SL SRB / DRB.

[0216] In one example, the way the relay UE maps the data packet to the relay backhaul bearer between the relay UE and the target UE, that is, the way the adapt PDU encapsulated by the adaptation layer is mapped to the relay BH bearer between the relay UE and the target UE, includes at least one of the following:

[0217] The relay UE maps forwarded data packets to the relay backhaul bearer based on the mapping relationship between the PC5 RLC bearer defined by the protocol or configured or pre-configured by the base station, such as mapping based on bearer identifier or mapping based on bearer / logical channel priority.

[0218] The logical channel priority of the relay UE based on PC5 RLC is mapped to the relay backhaul bearer with the same logical channel priority;

[0219] The relay UE maps the sidelink bearer identifier or signaling bearer priority contained in the received adaptation layer packet header to the relay backhaul bearer with the same bearer or logical channel priority.

[0220] Based on the sidelink bearer identifier or bearer priority contained in the received adaptation layer packet header, and the mapping relationship between the sidelink bearer or bearer priority and LCID defined by the protocol or configured or pre-configured by the base station, the relay UE maps the data packet to the relay backhaul bearer associated with the corresponding LCID.

[0221] The relay UE maps data packets to the relay backhaul bearer based on the 5QI, PQI, PFI, or QFI contained in the received adaptation layer packet header, and the mapping relationship between the 5QI, PQI, PFI, or QFI configured or pre-configured by the base station and the relay backhaul bearer.

[0222] After receiving the data packet, the target UE parses the data packet and identifies the source UE and SL bearer (SL SRB / DRB) corresponding to the data packet in the following way:

[0223] If a one-to-one mapping is configured, the target UE can identify the source UE and SL bearer based on the received relay BH bearer;

[0224] The source UE and SL bearer are identified based on information in the adaptation layer header, such as the source UE identifier, SL SRB identifier / priority, or logical channel identifier associated with the access BH bearer.

[0225] Based on the information in the adaptation layer header, such as the source UE identifier and SL DRB identifier, the source UE and SL bearer are identified;

[0226] The source UE and SL bearer are identified based on information in the adaptation layer header, such as the source UE identifier, 5QI / PQI / PFI / QFI, and the mapping relationship between the SL DRB and 5QI / PQI / PFI / QFI configured or pre-configured by the base station.

[0227] In summary, the adaptation layer header on the access BH link between the source UE and the relay UE may carry at least one of the following: target UE identifier, SL bearer identifier, bearer priority, and PQI / PFI / 5QI / QFI corresponding to the data packet; the adaptation layer header on the relay BH link between the relay UE and the target UE may carry at least one of the following: source UE identifier, SL bearer identifier, logical channel identifier associated with the access BH bearer, bearer priority, and PQI / PFI / 5QI / QFI corresponding to the data packet.

[0228] Optionally, to ensure end-to-end latency, the source UE can carry timestamp information in the adaptation layer packet header, and the relay UE can retain this timestamp information in the adaptation layer packet header when forwarding data. Then, after receiving data, the target UE can determine the end-to-end latency based on the source UE's timestamp information and the current time. Alternatively, the source UE or its base station can configure the latency requirements that the access BH bearer and relay BH bearer must meet (i.e., the latency on each PC5 BH link) based on service latency needs. This can be reflected in configuring an adaptation layer packet discard timer; if the data packet is not transmitted by the current timer expires, the data packet is discarded.

[0229] The source UE identifier and the target UE identifier are one of the following: L2 ID, or an identifier negotiated and allocated by the source UE and the target UE, or a local identifier allocated by the relay UE to the source UE and the target UE, or an application layer identifier.

[0230] For multi-hop relay scenarios, such as Figure 13 As shown, when relay UE1 forwards data sent from UE1 to UE3 to relay UE2, relay UE2 needs to know which source UE it came from and which destination UE it was sent to. Therefore, the adaptation layer header on the PC5 BH link (which can be called the intermediate relay BH) between relay UE1 and relay UE2 needs to carry at least the source UE identifier and the destination UE identifier. In addition, as mentioned above, in order for relay UE2 or the final UE3 to identify the corresponding SL bearer, the adaptation layer header can carry the SL bearer identifier; optionally, in order to assist relay UE2 in bearer mapping, the adaptation layer header can carry the bearer priority / the PQI / PFI / 5QI / QFI corresponding to the data packet, etc.

[0231] Optionally, if UE1 can send data from different source UE IDs to different target UE IDs via an access BH link (between UE1 and relay UE1), then the UE1 adaptation layer also needs to carry the source UE identifier; similarly, the adaptation layer between relay UE2 and target UE3 also needs to carry the target UE identifier. Therefore, in this case, the header formats of the adaptation layers between the source UE, the intermediate relay UEs, and the target UE are the same, carrying the same information, and at least the source UE identifier and the target UE identifier are required.

[0232] In one exemplary implementation Figure 14 This application provides a flowchart illustrating a sidelink relay communication method. This method is applicable to both control plane and user plane data forwarding in NR systems. The method can be executed by the sidelink relay communication device provided in this application for UE-to-UE relay communication. This sidelink relay communication device can be implemented in software and / or hardware and integrated into a communication device, which can be a relay UE for Layer 2 UE-to-UE relay communication.

[0233] like Figure 10 As shown, this application provides a sidelink relay communication method applied to Layer 2 UE-to-UE relay communication, including:

[0234] S410, The relay UE obtains the first configuration information for relay communication sent by the base station.

[0235] Among them, the first configuration information for relay communication refers to the configuration information of the base station for relay UE to perform relay communication, which may be bearer configuration information.

[0236] S420, The relay UE forwards data to the source UE and the target UE according to the first configuration information of the relay communication.

[0237] After the relay UE completes the bearer configuration establishment based on the bearer configuration information sent by the base station, it can forward relay data to the source UE and the target UE.

[0238] In the above technical solution, the relay UE receives the first configuration information for relay communication sent by the base station, so that the relay UE can complete the configuration according to the first configuration information for relay communication and then perform relay data forwarding for the source UE and the target UE, thereby realizing relay data forwarding between the source communication device and the target communication device applicable to 5G / NR system.

[0239] Specifically, before the relay UE obtains the first configuration information for relay communication, it also includes:

[0240] The relay UE reports forwarding service data related information to the base station, and the forwarding service data related information includes at least one of the following:

[0241] QoS information of services to be transmitted between the source UE and the target UE3, end-to-end sidelink bearer configuration between the source UE and the target UE, and PC5 RLC bearer configuration between the source UE and the relay UE.

[0242] Specifically, the base station receives forwarding service data related information reported by the relay UE, performs relay communication configuration for the relay UE based on the forwarding service data related information, and sends the first relay communication configuration information to the relay UE. The first relay communication configuration information includes at least one of the following: the relay backhaul bearer between the relay UE and the target UE, and the mapping relationship between the PC5 RLC bearer and the relay backhaul bearer between the source UE and the relay UE.

[0243] Furthermore, the aforementioned relay communication method also includes:

[0244] The source UE obtains the second configuration information for relay communication sent by the base station;

[0245] The source UE communicates with the target UE through the relay UE according to the second configuration information of the relay communication.

[0246] Specifically, before the source UE obtains the second configuration information for relay communication sent by the base station, the source UE reports the direct link terminal information to the base station, and the direct link terminal information includes at least one of the following:

[0247] Remote UE indication, target UE identifier, QoS flow information corresponding to the target UE identifier, and relay UE identifier.

[0248] Specifically, the base station receives the direct link terminal information reported by the source UE, configures relay communication for the source UE based on the direct link terminal information, and sends the second relay communication configuration information to the relay UE. The second relay communication configuration information includes at least one of the following:

[0249] The end-to-end sidelink bearer configuration between the source UE and the target UE, the PC5 RLC bearer configuration between the source UE and the relay UE, and the mapping relationship between the end-to-end sidelink bearer between the source UE and the target UE and the PC5 RLC bearer between the source UE and the relay UE;

[0250] The end-to-end sidelink bearer configuration between the source UE and the target UE includes any of the following: target UE identifier, bearer identifier or index, QoS flow mapping to sidelink bearer, whether to carry SDAP subheader, PDCP configuration, and PC5 RLC bearer identifier or index between the associated source UE and relay UE.

[0251] Specifically, before the source UE communicates with the target UE through the relay UE according to the second relay communication configuration information, the source UE interacts with the relay UE via PC5 RRC signaling to exchange the PC5 RLC bearer configuration between the source UE and the relay UE, the QoS information of the services to be transmitted between the source UE and the target UE, and the end-to-end sidelink bearer configuration between the source UE and the target UE; and / or,

[0252] The source UE and the target UE interact with each other by forwarding PC5 RRC signaling through the relay UE. The end-to-end sidelink bearer configuration between the source UE and the target UE is configured.

[0253] In one specific embodiment, it is assumed that UE1 is in RRC connected state under gNB1, UE3 is in no coverage, UE1 finds a relay UE and communicates with UE3 through the relay UE, and the relay UE is in RRC connected state under gNB2.

[0254] like Figure 15 As shown, UE1 discovers UE3 through relay UE. UE1 establishes L2 links with relay UE and relay UE with UE3 for data forwarding. The PC5-S connection establishment request message indicates relay forwarding. UE1 and UE3 establish L2 links through relay UE and exchange service type and QoS information (service / QoS info).

[0255] UE1 sends sidelink UE Information to the base station, reporting the target UE, relay UE, and QoS information for communication. The sidelink UE Information includes at least one of the following: target UE identifier (e.g., UE3 identifier), QoS flow information with the target UE identifier, and relay UE identifier. The QoS flow information includes any combination of the following: PFI, PQI, GFBR / MFBR, and communication range.

[0256] gNB1 performs bearer configuration based on the information reported by UE1, including at least one of the following: end-to-end sidelink bearer configuration between the source UE and the target UE, PC5 BH bearer configuration between the source UE and the relay UE, and the mapping relationship between the end-to-end sidelink bearer between the source UE and the target UE and the PC5 BH bearer between the source UE and the relay UE. The end-to-end sidelink bearer configuration between the source UE and the target UE includes any one of the following: target UE identifier, bearer identifier / index, QoS flow to SL DRB mapping, whether to carry SDAP subheader, PDCP configuration, and associated PC5 BH bearer identifier / index between the source UE and the relay UE; the PC5 BH bearer configuration between the source UE and the relay UE includes any one of the following: relay UE identifier, PC5 BH bearer identifier / index, associated end-to-end sidelink bearer identifier / index between the source UE and the target UE, logical channel identifier, logical channel group identifier, logical channel priority, RLC mode, RLC SN size, RLCAM polling related parameters, PBR, and BSD. Optionally, the relay BH bearer configuration between the relay UE and the target UE included in the bearer configuration information sent by gNB1 to UE1 may include at least one of the following: relay BH bearer identifier / index, RLC, logical channel, and MAC-related configuration.

[0257] UE1 receives the base station configuration and interacts with the relay UE via PC5 RRC signaling to configure the PC5 BH bearer between the source UE and the relay UE. Optionally, UE1 sends the QoS information of the service to be transmitted between UE1 and UE3 to the relay UE via PC5 RRC messages so that the relay UE can obtain or configure the relay BH bearer. The QoS information of the service to be transmitted between UE1 and UE3 includes at least one of the following: target UE identifier (e.g., UE3 identifier), QoS flow information with the target UE identifier, and relay UE identifier. The QoS flow information includes any combination of the following: PFI, PQI, GFBR / MFBR, and communication range. Optionally, UE1 sends the end-to-end sidelink bearer configuration between the source UE and the target UE configured by the base station to the relay UE via PC5 RRC messages.

[0258] The relay UE reports forwarding service data-related information to its base station, including at least one of the following: QoS information of the service to be transmitted between UE1 and UE3, end-to-end sidelink bearer configuration between the source UE and the target UE, and PC5 BH bearer configuration between the source UE and the relay UE. The QoS information of the service to be transmitted between UE1 and UE3 is either sent by UE1 to the relay UE via a PC5RRC message or carried in the adaptation layer header.

[0259] The base station configures the relay BH bearer between the relay UE and the target UE, as well as the mapping relationship between the PC5 BH bearer and the relay BH bearer between the source UE and the relay UE.

[0260] The relay UE receives the base station configuration and interacts with the target UE via PC5 RRC signaling to exchange relay BH bearer configuration. After receiving the base station configuration, UE1 interacts with UE3 via PC5 RRC signaling to exchange end-to-end sidelink bearer configuration between the source UE and the target UE.

[0261] It is worth noting that, Figure 15 There is no timing restriction between step 8 and steps 5-7, and step 8 can also be before step 5.

[0262] This embodiment also provides a sidelink relay communication device. Figure 16 A schematic diagram of a sidelink relay communication device provided in this application is shown below. Figure 16As shown in the embodiment of this application, a sidelink relay communication device can be configured in a communication device used for UE-to-network relay communication. The device includes: a first data receiving module 510 and a first data forwarding module 520, wherein...

[0263] The first data receiving module 510 is configured to receive data packets sent by a relay UE that are mapped by a source communication device onto a first bearer between the source communication device and the relay UE, wherein the source communication device includes a remote UE or a base station.

[0264] The first data forwarding module 520 is configured to map the data packet to a second bearer between the relay UE and the target communication device and transmit it to the target communication device, wherein the target communication device includes a base station or a remote UE.

[0265] The sidelink relay communication device provided in this embodiment for UE-to-network relay communication is used to implement the sidelink relay communication method for UE-to-network relay communication as described in the embodiments of this application. The implementation principle and technical effects of the sidelink relay communication device for UE-to-network relay communication provided in this embodiment are similar to those of the sidelink relay communication method for UE-to-network relay communication described in the embodiments of this application, and will not be repeated here.

[0266] In one example, the source communication device is a remote UE, and the target communication device is a base station;

[0267] The first data receiving module 510 is specifically configured to receive data packets sent by a remote UE, wherein the data packets are mapped by the remote UE from the Uu bearer to the PC5 radio link control RLC bearer between the remote UE and the relay UE based on a set mapping relationship and transmitted to the relay UE.

[0268] The first data forwarding module 520 is specifically configured to identify the Uu bearer of the remote UE to which the data packet belongs, and map the data packet onto the intermediate relay bearer between the relay UE and the base station for transmission to the base station.

[0269] In one example, the method by which a remote UE maps from a Uu bearer to a PC5 RLC bearer between the remote UE and the relay UE includes at least one of the following:

[0270] The remote UE maps Uu bearer data packets to corresponding PC5 RLC bearers;

[0271] The remote UE maps and / or delivers the Uu bearer data packets to the adaptation layer, which then processes them and maps them onto the PC5 RLC bearer.

[0272] In one example, the remote UE maps and / or delivers Uu bearer packets to the adaptation layer for processing, including:

[0273] Add an adapter layer header, wherein the adapter layer header includes at least one of the following:

[0274] The remote UE's Uu bearer identifier or index, relay forwarding indication, remote UE's Uu bearer priority, 5G service quality identifier 5QI, and QoS flow identifier QFI.

[0275] In one example, the first data forwarding module 520 is specifically configured to allow the relay UE to identify the Uu bearer of the remote UE to which the data packet belongs by means of a one-to-one mapping relationship between the Uu bearer of the remote UE obtained from the base station or a predefined remote UE and the PC5 RLC bearer, or by means of the Uu bearer identifier or index of the remote UE contained in the adaptation layer packet header.

[0276] In one example, the method by which the relay UE maps the data packet to the relay payload between the relay UE and the base station for transmission to the base station includes at least one of the following:

[0277] The relay UE maps the data packets to the Uu RLC bearer associated with the relay UE Protocol Data Unit (PDU) session, which is dedicated to data forwarding, for transmission.

[0278] The relay UE maps the data packet to a relay Uu backhaul bearer dedicated to relay data forwarding and sends it.

[0279] In one example, the first data forwarding module 520 is specifically configured to add a header to the data packet and map it to the relay Uu backhaul bearer. The header includes at least one of the following information: remote UE identifier, remote UE Uu bearer identifier, PC5 RLC bearer identifier, and logical channel identifier associated with the PC5 RLC bearer.

[0280] In one example, mapping the data packet to a relay Uu backhaul bearer includes at least one of the following methods:

[0281] The relay UE maps data packets to the relay Uu backhaul bearer based on the mapping relationship between the PC5 RLC bearer configured or pre-configured or pre-defined by the base station and the relay Uu backhaul bearer.

[0282] The logical channel priority of the relay UE based on PC5 RLC is mapped to the backhaul bearer of the relay Uu with the same logical channel priority;

[0283] The relay UE maps the priority of the remote UE Uu bearer contained in the received PC5 adaptation layer to the relay Uu backhaul bearer with the same bearer or logical channel priority.

[0284] The relay UE maps data packets to the relay Uu backhaul bearer based on the 5QI contained in the received PC5 adaptation layer packet header and the mapping relationship between the base station configured or pre-configured 5QI and the relay Uu backhaul bearer.

[0285] In one example, the source communication device is a base station, and the target communication device is a remote UE;

[0286] The first data receiving module 510 is specifically configured to receive data packets sent by the base station for the relay UE, wherein the data packets are mapped by the base station from the Uu bearer of the remote UE to the intermediate relay bearer between the base station and the relay UE and sent to the relay UE.

[0287] The first data forwarding module 520 is specifically configured to map the data packet onto the PC5 RLC bearer between the relay UE and the remote UE, and send it to the remote UE.

[0288] In one example, the method by which the base station maps the Uu bearer of the remote UE to the relay bearer between the base station and the relay UE includes at least one of the following:

[0289] The base station maps the Uu bearer data packets of the remote UE to the Uu RLC bearer associated with the relay UE PDU session, which is dedicated to data forwarding;

[0290] The base station delivers the Uu bearer data packet of the remote UE to the adaptation layer for processing, adds an adaptation layer header, and maps it to the relay Uu backhaul bearer dedicated to data forwarding. The adaptation layer header includes at least one of the following: remote UE identifier, remote UE Uu bearer identifier or index, remote UE Uu bearer priority, 5QI, QoS flow identifier QFI, PC5 RLC bearer identifier or logical channel identifier.

[0291] In one example, the method by which the relay UE maps the data packet to the PC5RLC bearer between the relay UE and the remote UE includes at least one of the following:

[0292] If the PC5 RLC bearer is a bidirectional bearer, then a reverse mapping is performed based on the mapping relationship between the uplink PC5 RLC bearer and the trunk Uu backhaul bearer;

[0293] Based on the mapping relationship between the base station configuration or pre-configured or predefined relay Uu backhaul bearer and the PC5 RLC bearer, data packets are mapped to the PC5 RLC bearer.

[0294] Based on the bearer priority or logical channel priority of the Uu relay backhaul bearer, data packets are mapped to PC5 RLC bearers with the same bearer or logical channel priority.

[0295] The relay UE maps data packets to PC5RLC bearers based on the Uu bearer identifier, index, or priority information of the remote UE in the adaptation layer packet header, and the mapping relationship between the Uu bearer of the remote UE and the PC5 RLC bearer configured, pre-configured, or pre-defined by the base station.

[0296] The relay UE maps data packets to the PC5 RLC bearer based on the 5QI or QFI in the adaptation layer packet header, and the mapping relationship between the priority of the 5QI or QFI configured or pre-configured or pre-defined by the base station and the priority of the PC5 RLC bearer.

[0297] The relay UE maps data packets to PC5 RLC bearers based on the PC5 RLC bearer identifier or logical channel identifier in the adaptation layer header;

[0298] The relay UE submits the parsed Uu interface data packets to the PC5 interface adaptation layer for processing, adds an adaptation layer header, and maps them to PC5 RLC bearer transmission; wherein, the adaptation layer header includes at least one of the following: the remote UE's Uu bearer identifier or index, the remote UE's Uu bearer priority, 5QI, QFI.

[0299] In one example, the remote UE identifier includes at least one of the following:

[0300] UE Layer 2 identifier, partial UE Layer 2 identifier, the cell radio network temporary identifier (C-RNTI) or local identifier configured for remote UEs by the base station, and the local identifier configured for remote UEs by the relay UE.

[0301] This embodiment also provides a sidelink relay communication device. Figure 17 A schematic diagram of a sidelink relay communication device provided in this application is shown below. Figure 17 As shown in the embodiment of this application, a sidelink relay communication device can be configured in a communication device used for UE-to-network relay communication. The device includes: a second information indication module 610 and a second data transmission module 620, wherein...

[0302] The second information indication module 610 is configured to indicate relay communication auxiliary information from the relay UE to the base station;

[0303] The second data transmission module 620 is configured to receive relay communication configuration information sent by the base station and perform data transmission based on the relay communication configuration information.

[0304] The sidelink relay communication device provided in this embodiment for UE-to-network relay communication is used to implement the sidelink relay communication method for UE-to-network relay communication as described in the embodiments of this application. The implementation principle and technical effects of the sidelink relay communication device for UE-to-network relay communication provided in this embodiment are similar to those of the sidelink relay communication method for UE-to-network relay communication described in the embodiments of this application, and will not be repeated here.

[0305] In one example, the relay communication auxiliary information includes at least one of the following: relay communication indication information, relay UE indication, relay type, and serving remote UE information, communication standard between the relay UE and the remote UE, and PC5 communication standard supported by the relay UE. In one example, the relay communication configuration information includes at least one of the following: relay Uu backhaul bearer configuration, PC5 RLC bearer configuration, and mapping relationship between relay Uu backhaul bearer and PC5 RLC bearer;

[0306] The relay Uu backhaul bearer configuration includes at least one of the following: signaling forwarding bearer indication, data forwarding bearer indication, bearer identifier, RLC mode, RLC configuration, logical channel identifier, logical channel priority, logical channel group identifier, and logical channel related configuration.

[0307] The PC5 RLC bearer is divided into bidirectional PC5 RLC bearer and unidirectional PC5 RLC bearer. The unidirectional PC5 RLC bearer configuration includes relevant parameters for sidelink bearer transmission or reception. The bidirectional PC5 RLC bearer configuration includes at least one of the following: RLC acknowledged mode or unacknowledged mode, and other relevant configuration information for RLC and logical channels.

[0308] The mapping relationship between the relay Uu backhaul bearer and the PC5 RLC bearer includes at least one of the following: bearer or logical channel identifier mapping, and bearer or logical channel priority mapping.

[0309] In one example, a configuration information forwarding module is also included, which is configured to forward remote communication configuration information configured by the base station for the remote UE to the relay UE;

[0310] The remote communication configuration information includes at least one of the following: Uu bearer configuration, PC5 RLC bearer configuration, and mapping relationship between Uu bearer and PC5 RLC bearer.

[0311] The Uu bearer configuration includes at least one of the following: bearer identifier, mapping from QFI or 5QI to Uu bearer, whether to carry the Service Data Adaptation Protocol (SDAP) header, and PDCP configuration;

[0312] The PC5 RLC bearer is divided into bidirectional PC5 RLC bearer and unidirectional PC5 RLC bearer. The unidirectional PC5 RLC bearer configuration includes relevant parameters for sidelink bearer transmission or reception. The bidirectional PC5 RLC bearer configuration includes at least one of the following: RLC acknowledged mode or unacknowledged mode, and other relevant configuration information for RLC and logical channels.

[0313] The mapping relationship between the Uu bearer and the PC5 RLC bearer includes at least one of the following: bearer or logical channel identifier mapping, bearer / logical channel priority mapping.

[0314] In one example, after the relay UE indicates relay communication assistance information to the base station, the base station indicates or updates the information between the relay UE and the remote UE to the Access and Mobility Management Function (AMF) entity, including at least one of the following:

[0315] Remote UE Layer 2 identifier, Remote UE Radio Access Network NG Application Protocol ID (RAN NGAP ID), Relay UE Layer 2 identifier, Relay UE RAN NGAP ID.

[0316] In one example, the relay UE and the remote UE use the first communication standard, the relay UE and the base station use the second communication standard, and after the remote UE establishes an RRC connection with the base station through the relay UE, the remote UE and the base station use the second communication standard.

[0317] In one example, the first communication standard is LTE, the second communication standard is NR, the Uu bearer of the remote UE is NR Uu bearer, the PC5 RLC bearer is LTE PC5 RLC bearer, and the relay Uu backhaul bearer is NR Uu backhaul bearer.

[0318] In one example, the mapping relationship between the remote UE NR Uu bearer and the LTE PC5 RLC bearer includes at least one of the following:

[0319] The mapping relationship between 5QI or QFI and PPPP (Packet Priority for Near Range Communication), the mapping relationship between priority and PPPP in 5QI, the mapping relationship between Uu bearer QoS and PPPP, and the mapping relationship between Uu bearer identifier or priority and PPPP.

[0320] In one example, the bearer mapping relationship obtained by the relay UE includes at least one of the following: the mapping relationship between the relay Uu backhaul bearer or logical channel priority and PPPP, the mapping relationship between the remote UE's Uu bearer and the relay Uu backhaul bearer, the mapping relationship between 5QI or QFI and the relay Uu backhaul bearer, and the mapping relationship between the remote UE's NR Uu bearer and the LTE PC5 RLC bearer.

[0321] In one example, the second communication standard is LTE, the first communication standard is NR, the remote UE's Uu bearer is LTE Uu bearer, the PC5 RLC bearer is NR PC5 RLC bearer, and the relay Uu backhaul bearer is LTE Uu backhaul bearer.

[0322] In one example, the mapping relationship between the remote UE LTE Uu bearer and the NR PC5 RLC bearer includes at least one of the following:

[0323] The mapping relationship between QCI and PQI, the mapping relationship between Uu bearer identifier or priority or QCI and PC5 RLC bearer logical channel priority, and the mapping relationship between Uu bearer identifier and PC5 RLC bearer logical channel identifier.

[0324] In one example, the bearer mapping relationship obtained by the relay includes at least one of the following:

[0325] The mapping relationships between QCI and PQI, PC5 RLC bearer logical channel priority and relay Uu backhaul bearer logical channel priority, remote UE Uu bearer and relay Uu backhaul bearer, QCI and PC5 RLC bearer logical channel priority, PQI and relay Uu backhaul bearer logical channel priority, and remote UE LTE Uu bearer and NR PC5 RLC bearer.

[0326] In one example, the mapping relationship is configured by the base station, or is pre-configured, or is configured by the ProSe or V2X control function of the proximity service, or is configured by OAM, or is defined by the protocol.

[0327] This embodiment also provides a sidelink relay communication device. Figure 18 A schematic diagram of a sidelink relay communication device provided in this application is shown below. Figure 18 As shown in the embodiment of this application, a sidelink relay communication device can be configured in a communication device used for UE-UE relay communication. The device includes: a third data receiving module 710 and a third data forwarding module 720, wherein...

[0328] The third data receiving module 710 is configured to receive data packets sent by the source UE to the target UE by the relay UE, wherein the data packets are mapped by the source UE to a PC5 RLC bearer between the source UE and the relay UE and sent to the relay UE;

[0329] The third data forwarding module 720 is configured to parse the data packet by the relay UE, identify the target UE corresponding to the data packet, map the data packet to the relay backhaul bearer between the relay UE and the target UE, and send it to the target UE.

[0330] The sidelink relay communication device provided in this embodiment for UE-to-UE relay communication is used to implement the sidelink relay communication method for UE-to-UE relay communication as described in the embodiments of this application. The implementation principle and technical effects of the sidelink relay communication device for UE-to-UE relay communication provided in this embodiment are similar to those of the sidelink relay communication method for UE-to-UE relay communication described in the embodiments of this application, and will not be repeated here.

[0331] In one example, the source UE adaptation layer processing module is configured such that, before the data packet is mapped to a PC5RLC bearer by the source UE, the data packet is submitted to the adaptation layer for processing by the source UE; wherein, the adaptation layer processing includes:

[0332] Add an adaptation layer header, wherein the adaptation layer header includes at least one of the following: target UE identifier, source UE identifier, sidelink bearer identifier, signaling bearer priority, PQI or PFI or 5QI or QFI.

[0333] In one example, the relay UE identifies the target UE corresponding to the data packet, including:

[0334] The relay UE identifies the sidelink bearer of the target UE corresponding to the data packet, wherein the relay UE identifies the sidelink bearer of the target UE corresponding to the data packet in at least one of the following ways:

[0335] Identification is achieved through the sidelink bearer identifier in the adapter layer header;

[0336] Identification is achieved through the mapping relationship between the sidelink bearer defined by the protocol, or configured or pre-configured by the base station, and the PC5 RLC bearer or the LCID;

[0337] The source UE identifies the relay UE by informing it of the mapping relationship between the sidelink bearer and the PC5 RLC bearer or the LCID based on PC5 RRC signaling.

[0338] In one example, the way in which the relay UE maps the data packet to the relay backhaul bearer between the relay UE and the target UE includes at least one of the following: the relay UE maps the forwarded data packet to the relay backhaul bearer based on the mapping relationship between the PC5 RLC bearer and the relay backhaul bearer defined by the protocol or configured or pre-configured by the base station.

[0339] The logical channel priority of the relay UE based on PC5 RLC is mapped to the relay backhaul bearer with the same logical channel priority;

[0340] The relay UE maps the sidelink bearer identifier or signaling bearer priority contained in the received adaptation layer packet header to the relay backhaul bearer with the same bearer or logical channel priority.

[0341] Based on the sidelink bearer identifier or bearer priority contained in the received adaptation layer packet header, and the mapping relationship between the sidelink bearer or bearer priority and LCID defined by the protocol or configured or pre-configured by the base station, the relay UE maps the data packet to the relay backhaul bearer associated with the corresponding LCID.

[0342] The relay UE maps data packets to the relay backhaul bearer based on the 5QI, PQI, PFI, or QFI contained in the received adaptation layer packet header, and the mapping relationship between the 5QI, PQI, PFI, or QFI configured or pre-configured by the base station and the relay backhaul bearer.

[0343] In one example, the system further includes: a relay UE adaptation layer processing module, configured to process the data packet via the adaptation layer before the relay UE maps the data packet to the relay backhaul bearer between the relay UE and the target UE; wherein the adaptation layer processing includes:

[0344] Add an adaptation layer header, wherein the adaptation layer header includes at least one of the following: source UE identifier, target UE identifier, sidelink bearer identifier, PC5 RLC bearer identifier or associated logical channel identifier, and sidelink bearer priority.

[0345] This embodiment also provides a sidelink relay communication device. Figure 19 A schematic diagram of a sidelink relay communication device provided in this application is shown below. Figure 19 As shown in the embodiment of this application, a sidelink relay communication device can be configured in a communication device used for UE-UE relay communication. The device includes: a fourth information acquisition module 810 and a fourth data forwarding module 820, wherein...

[0346] The fourth information acquisition module 810 is configured to allow the relay UE to acquire the first configuration information for relay communication sent by the base station;

[0347] The fourth data forwarding module 820 is configured to forward data between the source UE and the target UE according to the first configuration information of the relay communication.

[0348] The sidelink relay communication device provided in this embodiment for UE-to-UE relay communication is used to implement the sidelink relay communication method for UE-to-UE relay communication as described in the embodiments of this application. The implementation principle and technical effects of the sidelink relay communication device for UE-to-UE relay communication provided in this embodiment are similar to those of the sidelink relay communication method for UE-to-UE relay communication described in the embodiments of this application, and will not be repeated here.

[0349] In one example, a relay UE reporting module is also included, configured to report forwarding service data related information to the base station before the relay UE obtains the first configuration information for relay communication. The forwarding service data related information includes at least one of the following:

[0350] QoS information of services to be transmitted between the source UE and the target UE3, end-to-end sidelink bearer configuration between the source UE and the target UE, and PC5 RLC bearer configuration between the source UE and the relay UE.

[0351] In one example, the first configuration information for relay communication includes at least one of the following: a relay backhaul bearer between the relay UE and the target UE, and a mapping relationship between the PC5 RLC bearer and the relay backhaul bearer between the source UE and the relay UE.

[0352] In one example, it also includes: a source UE relay communication configuration module, configured to allow the source UE to obtain second relay communication configuration information sent by the base station; the source UE communicates with the target UE through the relay UE according to the second relay communication configuration information.

[0353] In one example, it also includes: a source UE reporting module, configured to report direct link terminal information to the base station before the source UE obtains the second configuration information for relay communication sent by the base station, wherein the direct link terminal information includes at least one of the following:

[0354] Remote UE indication, target UE identifier, QoS flow information corresponding to the target UE identifier, and relay UE identifier.

[0355] In one example, the second configuration information for relay communication includes at least one of the following:

[0356] The end-to-end sidelink bearer configuration between the source UE and the target UE, the PC5 RLC bearer configuration between the source UE and the relay UE, and the mapping relationship between the end-to-end sidelink bearer between the source UE and the target UE and the PC5 RLC bearer between the source UE and the relay UE;

[0357] The end-to-end sidelink bearer configuration between the source UE and the target UE includes any of the following: target UE identifier, bearer identifier or index, QoS flow mapping to sidelink bearer, whether to carry SDAP subheader, PDCP configuration, and PC5 RLC bearer identifier or index between the associated source UE and relay UE.

[0358] In one example, a bearer configuration interaction module is also included, configured to interact with the relay UE via PC5 RRC signaling before the source UE communicates with the target UE through the relay UE according to the second relay communication configuration information. This interaction includes the PC5 RLC bearer configuration between the source UE and the relay UE, the QoS information of the service to be transmitted between the source UE and the target UE, and the end-to-end sidelink bearer configuration between the source UE and the target UE; and / or, interacting with the target UE via PC5 RRC signaling forwarded by the relay UE.

[0359] This application provides a communication device. Figure 20 A schematic diagram of the structure of a communication device provided in this application is shown below. Figure 20 As shown, the communication device provided in this application includes: one or more processors 910 and a memory 920; the processor 910 of the communication device may be one or more. Figure 20 Taking a processor 910 as an example; memory 920 is used to store one or more programs; the one or more programs are executed by the one or more processors 910, causing the one or more processors 910 to implement the sidelink relay communication method applied to UE-to-network relay communication, or the sidelink relay communication method applied to UE-to-UE relay communication, as described in the embodiments of the present invention.

[0360] The processor 910 and memory 920 in the communication device can be connected via a bus or other means. Figure 20 Taking the example of a connection between China and Israel via a bus.

[0361] The memory 920, as a computer-readable storage medium, can be configured to store software programs, computer-executable programs, and modules, such as program instructions / modules corresponding to the sidelink relay communication method for UE-to-network relay communication as described in the embodiments of this application (e.g., the first data receiving module 510 and the first data forwarding module 520 in the sidelink relay communication device for UE-to-network relay communication, or, for example, the second information indicating module 610 and the second data transmission module 620 in the sidelink relay communication device for UE-to-network relay communication), or program instructions / modules corresponding to the sidelink relay communication method for UE-to-UE relay communication (e.g., the third data receiving module 710 and the third data forwarding module 720 in the sidelink relay communication device for UE-to-UE relay communication, or, for example, the fourth information acquisition module 810 and the fourth data forwarding module 820 in the sidelink relay communication device for UE-to-UE relay communication). The memory 920 may include a program storage area and a data storage area, wherein the program storage area may store the operating system and application programs required for at least one function; the data storage area may store data created according to the use of the device, etc. Furthermore, memory 920 may include high-speed random access memory, and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some instances, memory 920 may further include memory remotely located relative to processor 910, which can be connected to a communication node via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0362] This application embodiment also provides a storage medium storing a computer program, which, when executed by a processor, implements any of the sidelink relay communication methods described in this application embodiment, either for UE-to-network relay communication or for UE-to-UE relay communication.

[0363] One of the sidelink relay communication methods applied to UE-to-network relay communication includes:

[0364] The relay UE receives data packets that are mapped by the source communication device onto a first bearer between the source communication device and the relay UE, wherein the source communication device includes a remote UE or a base station;

[0365] The relay UE maps the data packet to a second bearer between the relay UE and the target communication device, and transmits it to the target communication device, wherein the target communication device includes a base station or a remote UE.

[0366] A sidelink relay communication method applied to UE-to-network relay communication includes:

[0367] The relay UE indicates relay communication auxiliary information to the base station;

[0368] The relay UE receives relay communication configuration information sent by the base station and performs data transmission based on the relay communication configuration information.

[0369] A sidelink relay communication method applied to UE-UE relay communication includes:

[0370] The relay UE receives a data packet sent by the source UE to the target UE, wherein the data packet is mapped by the source UE to a PC5 RLC bearer between the source UE and the relay UE and then sent to the relay UE;

[0371] The relay UE parses the data packet, identifies the target UE corresponding to the data packet, maps the data packet to the relay backhaul bearer between the relay UE and the target UE, and sends it to the target UE.

[0372] A sidelink relay communication method applied to UE-UE relay communication includes:

[0373] The relay UE obtains the first relay communication configuration information sent by the base station;

[0374] The relay UE forwards data to the source UE and the target UE according to the first configuration information of the relay communication.

[0375] The above description is merely an exemplary embodiment of this application and is not intended to limit the scope of protection of this application.

[0376] Those skilled in the art will understand that the term user terminal encompasses any suitable type of wireless user equipment, such as mobile phones, portable data processing devices, portable web browsers, or vehicle-mounted mobile stations.

[0377] Generally, the various embodiments of this application can be implemented in hardware or dedicated circuitry, software, logic, or any combination thereof. For example, some aspects can be implemented in hardware, while others can be implemented in firmware or software that can be executed by a controller, microprocessor, or other computing device, although this application is not limited thereto.

[0378] Embodiments of this application can be implemented by executing computer program instructions through a data processor of a physical device, for example, in a processor entity, or through hardware, or through a combination of software and hardware. The computer program instructions can be assembly instructions, Instruction Set Architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages.

[0379] Any block diagram of logical flow in the accompanying drawings of this application may represent program steps, or may represent interconnected logic circuits, modules, and functions, or may represent a combination of program steps and logic circuits, modules, and functions. The computer program may be stored on memory. Memory may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as, but not limited to, read-only memory (ROM), random access memory (RAM), optical storage devices and systems (Digital Video Disc (DVD) or Compact Disk (CD)), etc. Computer-readable media may include non-transitory storage media. The data processor may be of any type suitable to the local technical environment, such as, but not limited to, general-purpose computers, special-purpose computers, microprocessors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), and processors based on multi-core processor architectures.

[0380] A detailed description of exemplary embodiments of this application has been provided above through exemplary and non-limiting examples. However, various modifications and adjustments to the above embodiments will be apparent to those skilled in the art when considered in conjunction with the accompanying drawings and claims, without departing from the scope of the invention. Therefore, the proper scope of the invention will be determined by the claims.

Claims

1. A sidelink relay communication method, applied to a relay terminal (UE) for relay communication from the UE to the network, comprising: The relay UE receives data packets from the remote UE via the PC5 radio link control (RLC) bearer between the remote UE and the relay UE; The relay UE identifies the Uu bearer of the remote UE associated with the data packet based on the one-to-one mapping relationship defined between the Uu bearer of the remote UE and the PC5 RLC bearer. The relay UE maps the data packet to a dedicated relay Uu backhaul bearer for relay forwarding between the relay UE and the base station by adding a packet header to the data packet. The packet header includes the Uu bearer identifier of the remote UE; and The relay UE transmits the data packet to the base station.

2. The method according to claim 1, wherein, Adding a header to the data packet is performed by the adaptation layer of the relay UE, wherein the header includes a remote UE identifier.

3. The method according to claim 2, wherein, The remote UE identifier includes a local identifier configured by the base station for the remote UE.

4. The method according to claim 1, further comprising: The relay UE indicates relay communication assistance information to the base station; The relay UE receives relay communication configuration information from the base station and performs data transmission based on the relay communication configuration information.

5. The method according to claim 4, wherein, The relay communication auxiliary information includes: relay UE indication and information on the remote UE being served.

6. The method according to claim 4, wherein, The relay communication configuration information includes: The base station is configured with a local identifier for the remote UE; and The bearer mapping relationship includes the mapping relationship between the Uu bearer of the remote UE and the PC5 RLC bearer.

7. A communication device, comprising: One or more processors; Memory, used to store one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method as described in any one of claims 1-6.

8. A storage medium, characterized in that, The storage medium stores a computer program that, when executed by a processor, implements the method described in any one of claims 1-6.

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