Communication method and apparatus

Abstract

The present application provides a communication method and apparatus, which are applied to a multi-hop U2N relay architecture. The method comprises: receiving first information from a second terminal device, wherein the first information is used for indicating one or more pieces of path information, each piece of path information comprises information of a plurality of relay terminal devices, the plurality of relay terminal devices provide, for a first terminal device, relay services between the first terminal device and a first network device, the information of the plurality of relay terminal devices comprises identification information of the plurality of terminal devices and / or signal quality between adjacent relay terminal devices, and the second terminal device is a relay terminal device connected to the first terminal device among the plurality of relay terminal devices; and on the basis of the first information, communicating with the first network device. By means of the method, a first terminal device can obtain path information used for a relay service, so as to better determine a path for performing the relay service to a first network device.

Description

A communication method and apparatus

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202411554401.1, filed on October 31, 2024, entitled "A Communication Method and Apparatus", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of communication technology, and in particular to a communication method and apparatus. Background Technology

[0004] In communication systems, sidelink (SL) user equipment-to-network relay (U2N Relay) technology is a technique where a user equipment (UE) assists another UE in communicating with network equipment; it is also called relay technology. With technological advancements, the 3rd Generation Partnership Project (3GPP) proposed an evolution of SL U2N relay technology: multi-hop U2N relay technology.

[0005] In multi-hop U2N relay technology, the remote UE communicates with network devices through the cooperation of U2N relay UEs. At least one intermediate relay UE is involved between the remote UE and the U2N relay UE, providing relay services to the remote UE. However, how the remote UE selects the appropriate U2N relay UE in multi-hop U2N relay technology is a problem that urgently needs to be solved. Summary of the Invention

[0006] This application provides a communication method and apparatus to ensure the quality of service of terminal equipment.

[0007] Firstly, this application provides a communication method, wherein the execution subject of the method is a first terminal device or a module or chip within the first terminal device; the method is described here using the first terminal device as an example. The method includes:

[0008] The system receives first information from a second terminal device. This first information indicates one or more path information, each path information including information about multiple relay terminal devices. These multiple relay terminal devices provide relay services between the first terminal device and a first network device. The information about the multiple relay terminal devices includes identification information of the multiple relay terminal devices and / or signal quality between adjacent relay terminal devices. The second terminal device is a relay terminal device among the multiple relay terminal devices that is connected to the first terminal device. Based on the first information, the system communicates with the first network device.

[0009] In the above-described method, the first terminal device in this embodiment can obtain information about one or more relay terminal devices used to provide multi-hop relay services based on the received first information. For example, based on the first information, it can obtain the identification information of the relay terminal devices corresponding to each hop on one or more paths, thereby quickly determining the relay terminal devices used to provide relay services based on the identification information of the relay terminal devices, realizing rapid confirmation of multi-hop relay service paths. Furthermore, based on the first information, it can obtain the identification information of the relay terminal devices corresponding to each hop on one or more paths, as well as the signal quality between adjacent relay terminal devices on that path. Therefore, in addition to determining the relay terminal devices involved in the path, it can also combine the signal quality between adjacent terminal devices on that path to more intuitively and clearly understand the feasibility of using the path for relay services, thereby better assisting in the selection of high-quality relay service paths, etc., making it more adaptable and flexible.

[0010] As an example, the signal quality between adjacent relay terminal devices in this application embodiment includes, but is not limited to, the side link signal quality between adjacent relay terminal devices.

[0011] As an example, the information of the plurality of relay terminal devices in this application embodiment may include the signal quality between all adjacent relay terminal devices, or the signal quality between some adjacent relay terminal devices, which is not limited here.

[0012] In one possible implementation, communicating with the first network device based on the first information includes:

[0013] Based on the first information, first path information is selected, and communication with the first network device is performed based on the first path information; the first path information is one of the one or more path information. In one possible implementation, the step of communicating with the first network device based on the first path information includes:

[0014] A connection establishment request is sent to the second terminal device based on the first path information. The connection establishment request includes the identification information of one or more relay terminal devices corresponding to the first path information.

[0015] In one possible implementation, the method further includes:

[0016] Once the first condition is met, the selection of the first path information is triggered.

[0017] As an example, in this embodiment of the application, the first condition can be either the initial selection scenario of the relay service path or the reselection scenario of the relay service path, and is not limited here.

[0018] In one possible implementation, the first condition includes some or all of the following:

[0019] The first terminal device currently has no serving cell; the signal quality of the serving cell of the first terminal device is less than a first threshold; the first terminal device receives a relay service selection instruction from the upper layer; the signal quality between adjacent relay terminal devices in the relay service is less than a second threshold; a PC5 radio link failure (RLF) exists in the relay service; the first terminal device receives first indication information sent by one or more terminal devices corresponding to the relay service, the first indication information including some or all of the information indicating link abnormality, handover, cell reselection, or PC5 link release; the first terminal device receives a relay service reselection instruction from the upper layer.

[0020] As an example, the first condition corresponding to the initial path selection scenario may include: the first terminal device currently has no serving cell; the signal quality of the first terminal device's current serving cell is less than a first threshold; the first terminal device receives one or more relay service selection instructions from the upper layer. The first condition corresponding to the path reselection scenario may include: the signal quality between adjacent relay terminal devices in the relay service is less than a second threshold; the relay service has a PC5 radio link failure (RLF); the first terminal device receives first indication information sent by one or more terminal devices corresponding to the relay service, the first indication information including some or all of the information indicating link abnormality, handover, cell reselection, or PC5 link release; and the first terminal device receives a relay service reselection instruction from the upper layer.

[0021] In one possible implementation, the first threshold and the second threshold are determined by one or more of the following methods:

[0022] Based on network device configuration; pre-configured; protocol agreement; specified by the first terminal device.

[0023] In one possible implementation, the method further includes:

[0024] A broadcast request message is used to request a relay service. The request message includes identification information of the first terminal device, indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, and one or more of the number of multiple relay terminal devices supported in the relay service.

[0025] In the above method, in this embodiment of the application, the first terminal device, by indicating the number of multiple relay terminal devices supported in the relay service in the broadcast request message, enables the relay device receiving the request message to better plan the relay service path based on the request message.

[0026] For example, suppose the U2N relay UE determines, based on the obtained request message, that the number of relay terminal devices supported by the first terminal device is 3. The U2N relay UE sends response message 1 based on the request message. The response message 1 may carry the number of relay terminal devices supported by the first terminal device, which is 3. Relay terminal device 1 receives the response message 1 and sends response message 2 (the response message 2 includes the number 3). Relay terminal device 2 receives the response message 2 and sends response message 3 (the response message 3 includes the number 3). Relay terminal device 3 receives response message 3 and determines that more than three relay devices have not yet transmitted to the first terminal device. In this case, relay terminal device 3 can give up continuing to respond, thereby more effectively saving system overhead and better performing path planning.

[0027] In one possible implementation, the request message includes a first threshold and / or a second threshold.

[0028] In the above method, in this embodiment of the application, the first threshold and / or the second threshold can be indicated by the request message sent by the first terminal device.

[0029] For example, assuming that the U2N relay UE determines the second threshold to be A based on the obtained request message, the U2N relay UE sends a response message 1 based on the request message. The response message 1 may carry the second threshold A. When the relay terminal device 1 receives the response message 1 and determines that the signal quality between itself and the U2N relay UE is less than the second threshold A, the relay terminal device 1 can give up continuing to respond, thereby saving system overhead more effectively and performing better path planning.

[0030] As an example, in this embodiment of the application, the relay terminal device 1 can determine the signal quality between itself and the U2N relay UE based on the quality of the received response message 1; or, when there is a PC5 link between the relay terminal device 1 and the U2N relay UE, the signal quality between them can be obtained based on the PC5 link.

[0031] In one possible implementation, the first information is carried in a discovery message or a PC5 signaling message.

[0032] Secondly, this application provides a communication method, wherein the execution subject of the method is a second terminal device or a module or chip within the second terminal device; the method is described here using the second terminal device as an example. The method includes:

[0033] First information is determined, which indicates one or more path information, each path information including information of multiple relay terminal devices, the multiple relay terminal devices providing relay services between the first terminal device and the first network device, the information of the multiple relay terminal devices including identification information of the multiple relay terminal devices, and / or signal quality between adjacent relay terminal devices among the multiple relay terminal devices; wherein, the second terminal device is a relay terminal device among the multiple relay terminal devices connected to the first terminal device; the first information is sent to the first terminal device.

[0034] In the above-described method, the first terminal device in this embodiment can obtain information about one or more relay terminal devices on a path used to provide multi-hop relay services based on the received first information. For example, based on the first information, it can obtain the identification information of the relay terminal device corresponding to each hop on one or more paths, thereby quickly determining the relay terminal devices on the path used to provide relay services based on the identification information of the relay terminal devices, realizing rapid confirmation of multi-hop relay service paths. Furthermore, based on the first information, it can obtain the identification information of the relay terminal devices corresponding to each hop on one or more paths, as well as the signal quality between adjacent relay terminal devices on the path. Therefore, in addition to determining the relay terminal devices involved in the path, it can also combine the signal quality between adjacent terminal devices on the path to more intuitively and clearly understand the feasibility of using the path for relay services, thereby better assisting in the selection of high-quality relay service paths, etc., making it more adaptable and flexible.

[0035] In one possible implementation, the method further includes:

[0036] The system receives a first request message broadcast by the first terminal device. The first request message is used to request a relay service. The first request message includes one or more of the following: identification information of the first terminal device, indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, and the number of multiple relay terminal devices supported in the relay service.

[0037] In one possible implementation, the method further includes:

[0038] Broadcast a second request message; the second request message includes one or more of the following: identification information of the first terminal device, indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, the number of multiple relay terminal devices supported in the relay service, identification information of the second terminal device, and signal quality between the second terminal device and the first terminal device.

[0039] In the above method, in this embodiment of the application, when the second terminal device forwards the request message, it can also determine the content of the subsequent forwarded request message based on its own terminal device identification information and the signal quality between itself and the previous hop terminal device (i.e., the first terminal device), and so on. This enables each hop relay terminal device to better obtain the path information in the message forwarding process based on the received request message (the path information includes the relay terminal devices involved and the signal quality between adjacent relay terminal devices), better execute the path planning of the relay service, and better ensure the quality of transmission.

[0040] In one possible implementation, the method further includes:

[0041] The signal quality between the second terminal device and the first terminal device is determined to be no less than a third threshold.

[0042] Understandably, in order to improve the communication quality of relay services and reduce the probability of transmission failure, the relay terminal device in this application embodiment can determine the signal quality between itself and the previous hop relay terminal device during the message forwarding process (e.g., the signal quality is not less than the third threshold) before proceeding with subsequent forwarding.

[0043] In one possible implementation, the third threshold is determined by one or more of the following methods: based on network device configuration; pre-configured; agreed upon by a protocol; or specified by the first terminal device.

[0044] In one possible implementation, the method further includes:

[0045] The system receives a connection establishment request sent by the first terminal device based on the first path information, establishes a PC5 connection with the first terminal device, wherein the connection establishment request includes the identification information of one or more relay terminal devices corresponding to the first path information, and the first path information is one of the one or more path information; the system determines the next relay terminal device based on the identification information of the one or more relay terminal devices, and sends a connection establishment request to the next relay terminal device.

[0046] The above-described method, in this application embodiment, provides a method for establishing a relay service connection, which is more adaptable.

[0047] Thirdly, this application provides a communication method, wherein the execution subject of the method is a first relay terminal device or a module or chip within the first relay terminal device; the method is described here using the first relay terminal device as an example. The method includes:

[0048] The second information is determined, which includes identification information of one or more relay terminal devices and part or all of the signal quality between adjacent relay terminal devices; the second information is sent to the second relay terminal device; the first relay terminal device and the second relay terminal device provide relay services between the terminal device and the network device.

[0049] In one possible implementation, the one or more relay terminal devices include the first relay terminal.

[0050] In one possible implementation, the second message is carried in a discovery message or a PC5 signaling message.

[0051] In one possible implementation, sending the second information to the second relay terminal device includes:

[0052] The second information is sent to the second relay terminal device. The second information includes one or more path information, each path information including the identification information of the one or more relay terminal devices, and part or all of the signal quality between adjacent relay terminal devices.

[0053] The above method, in this application embodiment, provides a scenario for sending second information. For example, one or more path information can be packaged into one piece of information (i.e., the second information) for transmission, thereby effectively saving transmission overhead between relay terminal devices. As an example, in this application embodiment, the second information can be in the form of one or more lists, each list can correspond to one piece of path information, used to store the identification information of one or more relay terminal devices included in the path information, and / or the signal quality between adjacent relay terminal devices.

[0054] In one possible implementation, sending the second information to the second relay terminal device includes:

[0055] Send multiple pieces of the second information to the second relay terminal device. Each piece of the second information includes path information, which includes the identification information of the one or more relay terminal devices and part or all of the signal quality between adjacent relay terminal devices.

[0056] The above method, in this application embodiment, provides another scenario for sending second information. For example, when there are multiple path information that need to be sent, a second piece of information can be determined based on each path information, and then each second piece of information can be sent to the corresponding next-hop relay terminal device.

[0057] In one possible implementation, the method includes:

[0058] Multiple pieces of the second information are sent to the second relay device using different identifiers; each piece of the second information corresponds to an identifier.

[0059] The above method, by identifying each piece of secondary information, can effectively distinguish path information and better understand the source of each piece of path information.

[0060] In one possible implementation, determining the second information includes:

[0061] Receive third information sent by a third relay terminal device; when the third information includes the identification information of the third relay terminal device, determine the second information based on one or more of the third information, the identification information of the first relay terminal device, and the signal quality between the first relay terminal device and the third relay terminal device.

[0062] The above method, in this application embodiment, provides a scenario for determining the second information. For example, in the scenario based on mode A, each hop relay terminal device can determine the discovery message to be sent based on one or more of the received discovery message, its own identification information, and the signal quality between itself and the previous hop relay terminal device. This enables the first terminal device that obtains the discovery message to quickly obtain the entire path information based on the received discovery message and to better select the path for relay services.

[0063] In one possible implementation, determining the second information includes:

[0064] Receive third information sent by a third relay terminal device; when the third information includes the identification information of the one or more relay terminal devices, and part or all of the signal quality between adjacent relay terminal devices, determine the second information based on the third information.

[0065] The above method, in this application embodiment, provides another scenario for determining the second information. For example, in the scenario based on mode B, each hop relay terminal device can determine the request message to be sent based on one or more of the received request message, its own identification information, and the signal quality between itself and the previous hop relay terminal device. This enables the U2N relay UE that obtains the request message to quickly obtain the entire path information based on the received request message and carry the entire path information in the response message that replies based on the request message.

[0066] As an example, in this embodiment of the application, when forwarding response messages hop by hop, the content of the response message forwarded at each hop can be the same.

[0067] As an example, in this embodiment of the application, when forwarding response messages hop-by-hop, each hop can update the content of the response message to be forwarded based on the signal quality between itself and the relay terminal device of the previous hop. It is understood that the signal quality between relay terminal devices may change during the forwarding of request messages and during the replying of response messages. This method allows for better perception of the latest signal quality, thereby enabling better path planning for relay services.

[0068] In one possible implementation, the method further includes:

[0069] The system receives a first request message sent by the second relay terminal device. The first request message is used to request a relay service. The request message includes one or more of the following: the identification information of the first terminal device; the indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices; the number of multiple relay terminal devices supported in the relay service; and the identification information of the second relay terminal device.

[0070] In one possible implementation, the method further includes:

[0071] Based on the first request message, the identification information of the first relay terminal device, and the signal quality between the first relay terminal device and the second relay terminal device, a second request message is determined; the second request message is sent to the third relay terminal device. The second request message is used to request relay services. The second request message includes one or more of the following: the identification information of the first terminal device, indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, the number of multiple relay terminal devices supported in the relay service, the identification information of the second relay terminal device, the identification information of the first relay terminal device, and the signal quality between the first relay terminal device and the second relay terminal device.

[0072] In one possible implementation, the method further includes:

[0073] If the signal quality between the first relay terminal device and the third relay terminal device is determined to be no less than a fourth threshold, the second information is sent to the second relay terminal device.

[0074] In one possible implementation, the fourth threshold is determined by one or more of the following methods:

[0075] Based on network device configuration; pre-configured; protocol agreement.

[0076] In one possible implementation, the method further includes:

[0077] Receive the fourth threshold indicated by the first terminal device.

[0078] Fourthly, this application also provides a communication device capable of implementing any of the methods provided in any of the first to third aspects described above. This communication device can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more units or modules corresponding to the aforementioned functions.

[0079] In one possible implementation, the communication device includes a processor configured to support the communication device in performing corresponding functions of the network device, terminal device, or core network device described above. The communication device may also include a memory coupled to the processor, which stores necessary program instructions and data for the communication device. Optionally, the communication device further includes interface circuitry for supporting communication between the communication device and devices such as terminal devices.

[0080] In one possible implementation, the communication device includes corresponding functional modules, each used to implement the steps in the above method. The functions can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the functions described above.

[0081] In one possible implementation, the communication device includes a processing unit and a communication unit, which can perform the corresponding functions in the above method examples, as described in the methods provided in any of the first to third aspects, and will not be repeated here.

[0082] Fifthly, a computer program product storing instructions is provided, which, when read and executed by a computer, implements the method in any possible implementation of any of the first to third aspects.

[0083] Sixthly, a circuit is provided for performing the methods in any possible implementation of any of the first to third aspects described above. The circuit may include chip circuitry. Optionally, the circuit may also be coupled to a memory.

[0084] In a seventh aspect, a chip is provided, the chip including a processor, which, when executing a computer program or instructions, implements the methods in any possible implementation of any of the first to third aspects described above. Optionally, the chip may further include a memory, and the chip may be composed of chips or may include chips and other discrete devices.

[0085] Eighthly, a communication device is provided, including a processor that implements the method in any possible implementation of any of the first to third aspects by means of logic circuits or by executing computer programs or instructions.

[0086] Ninthly, a communication apparatus is provided, comprising a unit or module for performing a method in any possible implementation of any of the first to third aspects described above.

[0087] A tenth aspect provides a communication device, including a processor and an interface circuit. The interface circuit is configured to receive signals from other communication devices outside the communication device and transmit them to the processor, or to send signals from the processor to other communication devices outside the communication device. The processor, through logic circuits or by executing computer programs or instructions, implements the functional modules of the methods in any possible implementation of any of the first to third aspects. Optionally, the communication device further includes a memory for storing computer programs or instructions.

[0088] Eleventhly, a computer-readable storage medium is provided, which stores a computer program or instructions that, when executed by a processor, implement the method in any possible implementation of any of the first to third aspects.

[0089] In a twelfth aspect, embodiments of this application also provide a communication system. The communication system includes: a first terminal device, a second terminal device, and a third terminal device; the first terminal device is used to implement the methods in the first aspect and any possible implementations thereof; the second terminal device is used to implement the methods in the second aspect and any possible implementations thereof. Attached Figure Description

[0090] Figure 1 is a schematic diagram of a communication system architecture provided in an embodiment of this application;

[0091] Figure 2 is a schematic diagram of a communication architecture for an SL U2N relay provided in an embodiment of this application;

[0092] Figure 3 is a schematic diagram of a communication architecture for a SLU2U relay provided in an embodiment of this application;

[0093] Figure 4 is a schematic diagram of a multi-hop U2N relay network architecture provided in an embodiment of this application;

[0094] Figure 5 is a schematic diagram of another multi-hop U2N relay network architecture provided in an embodiment of this application;

[0095] Figure 6 is a schematic flowchart of a communication method provided in an embodiment of this application;

[0096] Figure 7 is a schematic diagram of the communication process in the first communication scenario provided in the embodiments of this application;

[0097] Figure 8 is a schematic diagram of the communication process in the second communication scenario provided in the embodiments of this application;

[0098] Figure 9 is a schematic diagram of the third communication scenario provided in the embodiments of this application;

[0099] Figure 10 is a schematic diagram of the communication process in the third communication scenario provided in the embodiments of this application;

[0100] Figure 11 is a schematic diagram of a communication device structure provided in an embodiment of this application;

[0101] Figure 12 is a schematic diagram of a communication device structure provided in an embodiment of this application;

[0102] Figure 13 is a schematic diagram of a communication device structure provided in an embodiment of this application. Detailed Implementation

[0103] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. The terms "first," "second," and corresponding terminology in this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be interchanged where appropriate; this is merely a way of distinguishing objects with the same attributes in the embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or device that comprises a series of units is not necessarily limited to those units, but may include other units not explicitly listed or inherent to these processes, methods, products, or devices. The methods and apparatus provided in the embodiments of this application are based on the same or similar technical concepts. Since the principles by which the methods and apparatus solve problems are similar, the implementations of the apparatus and methods can refer to each other, and repeated details will not be repeated.

[0104] The method provided in this application can be applied to various mobile communication systems, such as the Internet of Things (IoT), narrowband Internet of Things (NB-IoT), fourth-generation (4G) communication systems (e.g., Long Term Evolution (LTE)), fifth-generation (5G) communication systems (e.g., 5G New Radio (NR)), LTE and NR hybrid architectures, or new communication systems emerging in future communication developments. The communication system can also include machine-to-machine (M2M) networks, machine-type communication (MTC) networks, or other networks.

[0105] The following section will first explain some of the terms used in the embodiments of this application so that those skilled in the art can understand them.

[0106] Figure 1 is a schematic diagram of the architecture of the communication system applied in an embodiment of this application. The communication system 1000 includes a wireless access network 100 and a core network 200. Optionally, the communication system 1000 may also include an Internet 300. The wireless access network 100 includes at least one access network (AN) device, as shown in Figure 1 (110a and 110b), and at least one terminal device, as shown in Figure 1 (120a-120j). Specifically, 110a is a base station, 110b is a micro-station, 120a, 120e, 120f, and 120j are mobile phones, 120b is a car, 120c is a fuel dispenser, 120d is a home access point (HAP) deployed indoors or outdoors, 120g is a laptop computer, 120h is a printer, and 120i is a drone. The same terminal device or access network device can provide different functions in different application scenarios. For example, the mobile phones in Figure 1 are 120a, 120e, 120f and 120j. Mobile phone 120a can access base station 110a, connect to car 120b, communicate directly with mobile phone 120e and access HAP. Mobile phone 120b can access HAP and communicate directly with mobile phone 120a. Mobile phone 120f can access micro-station 110b, connect to laptop 120g and printer 120h. Mobile phone 120j can control drone 120i.

[0107] In this embodiment, the network device can be a device in a wireless network, and can also be referred to as a network apparatus, a radio access network device, or an access network device. For example, the network device can be a radio access network (RAN) node that connects a terminal device to a wireless network, and can also be referred to as an access network device. The network device includes, but is not limited to: base station, evolved NodeB (eNodeB), transmission reception point (TRP), next-generation NodeB (gNB) in a 5th generation (5G) mobile communication system, access network device in an open radio access network (O-RAN), base station in a future mobile communication system, or access node in a wireless fidelity (WiFi) system; or it can be a module or unit that performs some functions of a base station, such as a central unit (CU), a distributed unit (DU), a central unit control plane (CU-CP) module, or a central unit user plane (CU-UP) module. Access network equipment can be macro base stations, micro base stations, indoor stations, relay nodes, or donor nodes, etc. This application does not limit the specific technologies or equipment forms used in the network equipment.

[0108] In some implementations, network devices can include centralized units (CUs) and distributed units (DUs). This includes RAN devices at CU and DU nodes that separate the protocol layers of the gNB in ​​the NR system. Some protocol layer functions are centrally controlled by the CU, while the remaining partial or complete protocol layer functions are distributed across the DUs, which are then centrally controlled by the CU. Furthermore, the CU can be divided into a control plane (CU-CP) and a user plane (CU-UP). The CU-CP handles control plane functions, primarily including radio resource control (RRC) and the corresponding packet data convergence protocol (PDCP) (PDCP-C). PDCP-C is mainly responsible for control plane data encryption / decryption, integrity protection, and data transmission. The CU-UP handles user plane functions, primarily including the service data adaptation protocol (SDAP) and the corresponding PDCP (PDCP-U). SDAP is mainly responsible for processing core network data and mapping flows to bearers. PDCP-U is primarily responsible for data plane encryption / decryption, integrity protection, header compression, sequence number maintenance, and data transmission. CU-CP and CU-UP are connected via the E1 interface. CU-CP represents the gNB connected to the core network via the NG interface and to the DU via the F1 interface control plane (F1-C). CU-UP is connected to the DU via the F1 interface user plane (F1-U). Alternatively, PDCP-C may also be located within CU-UP.

[0109] It is understood that CU (including CU-CP or CU-UP) or DU may have different names in different systems, but those skilled in the art will understand their meaning. For example, in an open radio access network (O-RAN) system, CU can also be called O-CU (open CU), DU can also be called O-DU, CU-CP can also be called O-CU-CP, and CU-UP can also be called O-CU-UP. For ease of description, this application uses CU, CU-CP, CU-UP, and DU as examples. Network devices may also include active antenna units (AAU). CU implements some of the functions of gNB, and DU implements some of the functions of gNB. For example, CU is responsible for handling non-real-time protocols and services, implementing the functions of the RRC layer. DU is responsible for handling physical layer protocols and real-time services, implementing the functions of the radio link control (RLC) layer, media access control (MAC) layer, and physical (PHY) layer. In some deployments, the CU can also be divided into a centralized unit control plane (CU-CP) node and a centralized unit user plane (CU-UP) node. The CU-CP is responsible for control plane functions, while the CU-UP is responsible for user plane functions.

[0110] The terminal device involved in the embodiments of this application can be a wireless terminal device capable of receiving network device scheduling and instruction information. The terminal device can be referred to as a terminal device, or it can also be called user equipment (UE), terminal, mobile station (MS), mobile terminal (MT), etc. The terminal device can be a device that includes wireless communication functions (providing voice / data connectivity to the user). For example, a handheld device with wireless connectivity, or an in-vehicle device, in-vehicle module, etc. Currently, examples of terminal devices include: mobile phones, tablets, laptops, PDAs, mobile internet devices (MIDs), wearable devices, virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, wireless terminals in vehicle-to-everything (V2X) communication, wireless terminals in vehicle-to-everything (V2X) communication, intelligent vehicles, in-vehicle infotainment systems (or onboard transmitters) (T-boxes), machine-to-machine / machine-type communications (M2M / MTC) terminal devices, and the Internet of Things (IoT). Wireless terminals in industrial control systems can include devices such as IoT (Internet of Things) terminals. For example, terminal devices can be in-vehicle equipment, vehicle-mounted modules, vehicles, on-board units (OBUs), roadside units (RSUs), T-boxes, chips, or systems-on-chips (SoCs), which can be installed in vehicles, OBUs, RSUs, or T-boxes. Wireless terminals in industrial control systems can be cameras, robots, etc. Wireless terminals in smart homes can be televisions, air conditioners, robot vacuums, speakers, set-top boxes, etc.Terminal devices can also be V2X devices, such as smart cars, digital cars, unmanned cars, driverless cars, pilotless cars, autonomous cars, pure electric vehicles (EVs), hybrid electric vehicles (HEVs), range-extended electric vehicles (REEVs), plug-in hybrid electric vehicles (PHEVs), new energy vehicles, and roadside units (RSUs). Terminal devices can also be devices in device-to-device (D2D) communication, such as electricity meters and water meters. Furthermore, in this embodiment, the terminal device can also be a terminal device in an IoT system. IoT is an important component of future information technology development, and its main technical characteristic is connecting objects to networks through communication technologies, thereby realizing an intelligent network of human-machine interconnection and machine-to-machine interconnection.

[0111] Sidelink (SL) UE-to-network relay (U2N Relay) technology is a technique where a user equipment (UE) assists another UE in communicating with network equipment; it is also called relay technology. Figure 2 shows a schematic diagram of the communication architecture of SL U2N relay. The remote UE communicates with the network equipment through the cooperation of the relay UE. The remote UE and the relay UE communicate via the sidelink, with the corresponding interface called PC5. The relay UE and the network equipment communicate via the Uu interface.

[0112] To expand the range of sidelink communication, a user equipment-to-user equipment (U2U) relay technology (SL) is proposed. Figure 3 shows a schematic diagram of the SL U2U relay communication architecture. This communication system can include multiple terminal devices, with a source terminal device, a relay terminal device, and a target terminal device illustrated in the figure. The source and target terminal devices can also be referred to as remote terminal devices. Multiple terminal devices can communicate with each other via a PC5 interface. Optionally, the communication system can also include at least one network device, with one network device illustrated in the figure. All of the multiple terminal devices can be located outside the coverage area (OOC) of the network device, or all of the multiple terminal devices can be located within the coverage area of ​​the network device, or some of the multiple terminal devices can be located within the coverage area of ​​the network device. The figure illustrates an example where multiple terminal devices are located within the coverage area of ​​the network device. In this embodiment, the source terminal device, relay terminal device, and target terminal device may be in a radio resource control (RRC) connected state, an RRC idle state, or an RRC inactive state, without restriction.

[0113] In sidelink communication scenarios, when the signal quality between UEs is poor, or when UEs cannot establish a sidelink connection, if a UE supports U2U relay communication, it can initiate a discovery process to find a suitable relay UE in the vicinity and communicate with the peer UE through the relay UE. The discovery process has two modes: Mode A and Mode B.

[0114] In Mode A, a UE with U2U relay capability detects and learns about surrounding end UEs. It then broadcasts this information via announcement messages. For example, it receives a discovery message from a nearby end UE carrying a relay indication, which indicates that the UE supports U2U relay. The U2U relay UE uses its own layer-2 identifier (L2 ID) as the source L2 ID and the L2 ID associated with the announcement message as the target L2 ID. After receiving the announcement message from the U2U relay UE, end UE1 determines, based on the list of end UE information contained in the announcement message, that it can connect to end UE2 via the U2U relay UE. Subsequently, it triggers a unicast connection establishment procedure to establish an end-to-end connection with end UE2.

[0115] In Mode B, UE1 (or remote UE, Source UE) broadcasts a discovery solicitation message. UE1 uses its upper-layer assigned L2 ID as the source L2 ID and the L2 ID associated with the discovery solicitation message as the target L2 ID. Upon receiving the discovery solicitation from UE1, the U2U relay UE decides to continue broadcasting the solicitation as a relay. The U2U relay UE uses its own upper-layer assigned L2 ID as the source L2 ID and the L2 ID associated with the discovery solicitation message as the target L2 ID, and then sends a discovery solicitation. UE2 receives the matching information of the source UE in the discovery solicitation message and replies with a discovery response message. UE2 uses its own upper-layer assigned L2 ID as the source L2 ID, and the U2U relay UE uses the source L2 ID from its discovery solicitation message as the target L2 ID, then sends its own discovery solicitation message. The U2U relay UE then replies with a discovery response message to UE1. The U2U relay UE uses its own L2 ID assigned by its upper layer as the source L2 ID, and the source L2 ID used in the discovery request message received by UE1 as the destination L2 ID, and sends the discovery response message. UE1 may receive discovery response messages forwarded by multiple relay UEs, meaning multiple relay UEs are willing to provide relay for communication between the source UE and the target UE. At this point, UE1 can select a relay UE, determine the relay UE, and establish a relay connection with the target UE through the relay UE.

[0116] Figure 4 illustrates a multi-hop U2N relay network architecture. In multi-hop U2N relay technology, the remote UE communicates with network device 1 through the cooperation of U2N relay UEs. At least one intermediate relay UE is included between the remote UE and the U2N relay UE, providing relay services between the remote UE and the U2N relay UE.

[0117] In a multi-hop U2N relay network architecture, in a multi-hop relay scenario, the remote UE discovers suitable intermediate relay UEs and U2N relay UEs in the vicinity through a discovery process, which is equivalent to selecting a path to connect to the network. The remote UE can measure the sidelink signal quality between adjacent intermediate relay UEs and select an intermediate relay UE accordingly. However, as shown in Figure 5, the same intermediate relay UE adjacent to the remote UE may be connected to different U2N relay UEs. In this case, the remote UE cannot select a U2N relay UE based solely on the sidelink signal quality with its adjacent intermediate relay UEs.

[0118] Based on this, this application provides a communication method that enables a remote UE in a multi-hop U2N relay architecture to obtain information about one or more relay UEs on a path used to provide multi-hop relay services (e.g., the identification information of the relay UE corresponding to each hop on the path and the signal quality between adjacent relay UEs on the path). Based on the obtained relay UE information, the method can select and reselect relays with higher quality and faster speed, effectively ensuring the communication quality in multi-hop relay scenarios.

[0119] In this embodiment, the multi-hop relay service can be understood as a communication transmission established between a remote UE and a network device through multiple terminal devices. Information transmission (e.g., information forwarding) between two adjacent terminal devices can be understood as one hop. The terminal device currently receiving information can be understood as the current hop terminal device, the terminal device sending information to the current hop terminal device can be understood as the previous hop terminal device based on the current hop terminal device, and the terminal device that the current hop terminal device needs to send information can be understood as the next hop terminal device based on the current hop terminal device. When the remote UE communicates with the network device through multiple terminal devices, the order in which the transmitted information passes through multiple terminal devices from the remote UE to the network device can be understood as the path of the multi-hop relay service. For example, if the remote UE communicates with the network device sequentially through relay UE1, relay UE2, and relay UE3, the communication transmission process can be understood as communication transmission based on the multi-hop relay service, and the corresponding multi-hop relay service path can be remote UE -- relay UE1 -- ​​relay UE2 -- relay UE3 -- network device.

[0120] The network architecture and business scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. As those skilled in the art will know, with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0121] It is understood that this application does not specifically limit the structure of the execution subject of the method provided in the embodiments of this application. It can be applied to modules in terminal devices or network devices, as long as they can communicate according to the method provided in the embodiments of this application by running a program that records the code of the method provided in the embodiments of this application.

[0122] Figure 6 shows a schematic flowchart of a communication method provided in an embodiment of this application. In this method, the multi-hop U2N relay architecture may include one or more relay terminal devices for providing relay services between the first terminal device and the first network device. It should be noted that this embodiment does not limit the network device communicating through the relay service. The term "first network device" is used generically and does not constitute a limitation on the network device in this embodiment. The first terminal device can determine the network device communicating through the relay service based on actual circumstances. The first terminal device can be a remote UE in the multi-hop U2N relay architecture or a chip or module within the remote UE; the second terminal device can be a relay terminal device connected to the first terminal device or a chip or module within the relay terminal device; the third terminal device can be a U2N relay UE in the multi-hop U2N relay architecture or a chip or module within the U2N relay UE.

[0123] Step 601: The second terminal device determines the first information.

[0124] As an example, in this embodiment of the application, the first information is used to indicate one or more path information, each path information including information of multiple relay terminal devices, the multiple terminal devices providing relay services between the first terminal device and the first network device.

[0125] The information of the multiple relay terminal devices described in this application embodiment may include various situations, and is not limited to the following five situations:

[0126] Includes Case 1: the identification information of the plurality of relay terminal devices, and the signal quality between all adjacent relay terminal devices among the plurality of relay terminal devices.

[0127] As an example, the signal quality between adjacent relay terminal devices in this application embodiment includes, but is not limited to, the side link signal quality between adjacent relay terminal devices.

[0128] For example, an optional path for providing relay services between the first terminal device and the first network device is: first terminal device - second terminal device - terminal device A - terminal device B - first network device; then the information of the plurality of relay terminal devices can be the identification information of the second terminal device, the identification information of the terminal device A, the identification information of the terminal device B, the sidelink signal quality between the second terminal device and the terminal device A, and the sidelink signal quality between the terminal device A and the terminal device B.

[0129] Case 2 includes: the identification information of the plurality of relay terminal devices, and the signal quality between some adjacent relay terminal devices among the plurality of relay terminal devices.

[0130] For example, an optional path for providing relay services between the first terminal device and the first network device is: first terminal device - second terminal device - terminal device A - terminal device B - first network device; then the information of the plurality of relay terminal devices can be the identification information of the second terminal device, the identification information of the terminal device A, the identification information of the terminal device B, and the sidelink signal quality between the second terminal device and the terminal device A.

[0131] Case 3 includes the identification information of the multiple relay terminal devices.

[0132] For example, an optional path for providing relay services between the first terminal device and the first network device is: first terminal device - second terminal device - terminal device A - terminal device B - first network device; then the information of the plurality of relay terminal devices can be the identification information of the second terminal device, the identification information of the terminal device A, and the identification information of the terminal device B.

[0133] Case 4: Signal quality between all adjacent relay terminal devices among the plurality of relay terminal devices.

[0134] For example, an optional path for providing relay services between the first terminal device and the first network device is: first terminal device - second terminal device - terminal device A - terminal device B - first network device; then the information of the plurality of relay terminal devices can be the side link signal quality between the second terminal device and the terminal device A, and the side link signal quality between the terminal device A and the terminal device B.

[0135] Case 5: Signal quality between some adjacent relay terminal devices among the plurality of relay terminal devices.

[0136] For example, an optional path for providing relay services between the first terminal device and the first network device is: first terminal device - second terminal device - terminal device A - terminal device B - first network device; then the information of the plurality of relay terminal devices can be the side link signal quality between terminal device A and terminal device B.

[0137] As an example, when the first information in this application embodiment is used to indicate multiple path information, in order to make it easier for the first terminal device to select path information, each path information in this application embodiment may also correspond to a path score, so that the first terminal device can quickly select a suitable relay service scheme based on the path scores corresponding to the multiple path information. The path score may be determined based on the signal quality between all adjacent relay terminal devices in the corresponding path information.

[0138] Step 602: The second terminal device sends the first information to the first terminal device.

[0139] As an example, in this embodiment of the application, the first information may be carried in a discovery message or a PC5 signaling message.

[0140] As an example, there are several ways in which the second terminal device sends the first information to the first network device in this application embodiment, and these are not limited to the following:

[0141] Sending scenario 1: Send the second information to the second relay terminal device. The second information includes one or more path information, each path information including the identification information of the one or more relay terminal devices, and part or all of the signal quality between adjacent relay terminal devices.

[0142] For example, the second information can be in the form of multiple lists, each list can correspond to a path information, used to indicate the identification information and other contents of multiple relay terminal devices in the corresponding path information.

[0143] Sending scenario 2: Send multiple pieces of the second information to the second relay terminal device. Each piece of the second information includes path information, which includes the identification information of the one or more relay terminal devices and part or all of the signal quality between adjacent relay terminal devices.

[0144] As an example, in order to better distinguish the sent second messages, this application embodiment can send multiple second messages to the second relay device using different identifiers, wherein each second message corresponds to an identifier.

[0145] For example, in this embodiment of the application, the identifier corresponding to the second information can be an L2ID.

[0146] Step 603: The first terminal device receives the first information from the second terminal device.

[0147] As an example, the communication transmission model between the first terminal device and the first network device in this application embodiment includes, but is not limited to, model A and model B. Based on different transmission modes, the relay service path planning method between the first terminal device and the first network device in this application embodiment is also different, and is not limited to the following description:

[0148] Based on model A:

[0149] In this embodiment of the application, under model A mode, the third terminal device (U2N relay UE) connected to the first network device among the plurality of relay terminal devices will broadcast a first discovery message. The first discovery message may include the identification information of the third terminal device and / or the number of plurality of relay terminal devices supported in the relay service.

[0150] Then, the first relay terminal device that receives the first discovery message determines a second discovery message based on the first discovery message. The second discovery message can be understood as supplementing the content of the first discovery message based on its own identification information and the sidelink signal quality between the first relay terminal device and the third terminal device. For example, the second discovery message includes the identification information of the third terminal device, the number of multiple relay terminal devices supported in the relay service, the identification information of the first relay terminal device, and part or all of the sidelink signal quality between the first relay terminal device and the third terminal device.

[0151] The first relay terminal device sends the second discovery message. Then, the second relay terminal device, upon receiving the second discovery message, determines a third discovery message based on the second discovery message. The third discovery message can be understood as supplementing the content of the second discovery message based on the identification information of the second relay terminal device and the sidelink signal quality between the second relay terminal device and the first relay terminal device. For example, the third discovery message includes the identification information of the third terminal device, the number of multiple relay terminal devices supported in the relay service, the identification information of the first relay terminal device, the sidelink signal quality between the first relay terminal device and the third terminal device, and part or all of the identification information of the second relay terminal device and the sidelink signal quality between the second relay terminal device and the first relay terminal device. This process continues until the first terminal device receives a discovery message sent based on the above forwarding method, thereby determining the first information based on the discovery message. It should be noted that the number of relay terminal devices in this example is merely an example to more clearly illustrate the solution of this application and does not constitute a limitation on the embodiments of this application.

[0152] As an example, in the process of forwarding a message in this application embodiment, if the current relay terminal device determines that the signal quality between it and the previous relay terminal device is less than a threshold, then the message forwarding can be abandoned.

[0153] Based on Model B:

[0154] In the Model B mode of this application embodiment, the first terminal device broadcasts a first request message. The first request message is used to request a relay service. The first request message includes the identification information of the first terminal device, the indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, and one or more of the multiple relay terminal devices supported in the relay service.

[0155] Then, upon receiving the first request message, the first relay terminal device determines a second request message based on the first request message. The second request message can be understood as supplementing the content of the first request message based on its own identification information and the sidelink signal quality between the first relay terminal device and the first terminal device. For example, the second request message includes a request for relay service, the identification information of the first terminal device, and indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices. The second request message includes part or all of the number of multiple relay terminal devices supported in the relay service, the identification information of the first relay terminal device, and the sidelink signal quality between the first relay terminal device and the first terminal device.

[0156] The first relay terminal device sends the second request message. Then, the second relay terminal device, upon receiving the second request message, determines a third request message based on the second request message. The third request message can be understood as supplementing the content of the second request message based on the identification information of the second relay terminal device and the sidelink signal quality between the second and first relay terminal devices. For example, the third request message may request relay services. The third request message may include the identification information of the first terminal device, indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, the number of multiple relay terminal devices supported in the relay service, the identification information of the first relay terminal device, the sidelink signal quality between the first and second relay terminal devices, and the identification information of the second relay terminal device and some or all of the sidelink signal quality between the second and first relay terminal devices. This process continues until the third terminal device receives a request message sent based on the above forwarding method.

[0157] Then, the third terminal device can determine a first response message based on the received request message. The first response message includes information about multiple relay terminal devices. The multiple relay terminal devices provide relay services between the first terminal device and the first network device. The information about the multiple relay terminal devices includes the identification information of the multiple relay terminal devices and / or the signal quality between adjacent relay terminal devices among the multiple relay terminal devices.

[0158] The third terminal device, based on the information of the plurality of relay terminal devices, determines the next-hop relay terminal device to receive the response message and sends the first response message to the corresponding next-hop relay terminal device. The relay terminal device receiving the first response message, based on the information of the plurality of relay terminal devices included in the first response message, determines the next-hop relay terminal device to receive the response message and sends a second response message to the corresponding next-hop relay terminal device. This process continues until the first terminal device receives a response message sent using the aforementioned forwarding method. Thus, the first information is determined based on the response message. It should be noted that the number of relay terminal devices in this example is merely an example to more clearly illustrate the solution of this application and does not constitute a limitation on the embodiments of this application.

[0159] As an example, the thresholds described in Modes A and B of this application embodiment can be obtained based on network device configuration, or pre-configured, or agreed upon by the protocol. In the scenario based on Mode B, the threshold can also be indicated by the first terminal device; for example, the threshold can be carried in the request message sent by the first terminal device.

[0160] As an example, when there is a PC5 connection between adjacent terminal devices in this application embodiment, the adjacent terminal devices can forward relevant messages based on the PC5 connection between them, which is not limited here.

[0161] As an example, the lateral link signal quality between adjacent terminal devices described in this application can be obtained by the adjacent terminal devices measuring the signal quality based on the established PC5 connection between them; or, the lateral link signal quality between adjacent terminal devices can be determined by the current relay terminal device based on the quality of the message received from the previous hop relay terminal device.

[0162] Step 604: The first terminal device communicates with the first network device based on the first information.

[0163] As an example, in this embodiment of the application, the first terminal device selects first path information based on the first information and communicates with the first network device based on the first path information; wherein, the first path information is one of the one or more path information.

[0164] Specifically, in this embodiment of the application, the first terminal device may send a connection establishment request to the second terminal device based on the first path information, wherein the connection establishment request includes the identification information of one or more relay terminal devices corresponding to the first path information.

[0165] As an example, the application scenarios of the scheme described in Figure 6 above in this application embodiment are not limited to the initial path selection or re-path selection between the first terminal device and the first network device for relay services.

[0166] For example, the scenario in which the first terminal device and the first network device establish an initial communication connection can be that the first terminal device determines, based on the first information, a sequential connection with the first network device based on a first set of terminal device identifiers. For instance, if the first set of terminal device identifiers and the sequence are second terminal device, terminal device A, and terminal device C, then the initial communication connection established between the first terminal device and the first network device based on the first set of terminal device identifiers is: first terminal device - second terminal device - terminal device A - terminal device C - first network device.

[0167] In this embodiment of the application, the conditions for triggering the initial path selection between the first terminal device and the first network device include, but are not limited to, some or all of the following:

[0168] (1) The first terminal device currently has no serving cell;

[0169] (2) The signal quality of the current serving cell of the first terminal device is less than the threshold quality;

[0170] (3) The first terminal device receives a relay service selection instruction sent from the upper layer.

[0171] An exemplary scenario for re-path selection between the first terminal device and the first network device could be that the first terminal device, based on the first information, determines that the sequential connection with the first network device is changed from the first set of terminal device identifiers to the second set of terminal device identifiers. For example, if the second set of terminal device identifiers and the sequence are second terminal device, terminal device A, and terminal device D, then the first terminal device, based on the second set of terminal device identifiers, changes the established communication connection with the first network device (first terminal device - second terminal device - terminal device A - terminal device C - first network device) to first terminal device - second terminal device - terminal device A - terminal device D - first network device.

[0172] The conditions for triggering a re-path selection between the first terminal device and the first network device in this embodiment include, but are not limited to, some or all of the following:

[0173] (1) In the relay service, there are signal quality issues between adjacent terminal devices that are less than the threshold quality.

[0174] (2) The relay service has a PC5 radio link failure (RLF).

[0175] (3) The first terminal device receives a first indication information sent by one or more terminal devices corresponding to the relay service. The first indication information includes some or all of the information indicating link abnormality, handover, cell reselection or PC5 link release.

[0176] (4) The first terminal device receives a relay service reselection instruction sent from the upper layer.

[0177] In order to better understand the communication method of this application, it is introduced based on different scenarios, which are not limited to the following three application scenarios:

[0178] For ease of description, it is assumed that the number of relay terminal devices in Embodiments 1 and 2 below is 3, including relay UE1 (the relay UE1 is an intermediate relay UE), relay UE2 (the relay UE2 is an intermediate relay UE), and relay UE3 (the relay UE3 may and is not limited to a U2N relay UE). The number of relay UEs in this embodiment is only an example and does not constitute a limitation on the embodiment of this application. The specific number can be determined according to the actual situation. For example, the number of relay UEs may be 4 or more, or even fewer.

[0179] Example 1: In the scenario based on the model A discovery process, the first terminal device (which can be called a remote UE) obtains relevant information (such as signal quality and relay UE identifier) ​​of all relay UEs on the path based on the relay UE3 discovery process, and uses it to select or reselect relay UEs.

[0180] Figure 7 shows a flowchart of a communication method in this scenario provided by an embodiment of this application. The specific implementation steps can be referred to the following process:

[0181] Step 701: Relay UE3 broadcasts discovery message 1.

[0182] As an example, the broadcast discovery message 1 in this embodiment may carry the identification information of the relay UE3 (e.g., User Info ID). The discovery message 1 may also carry a relay service code (RSC), which can be used to indicate that relay service is available. In addition, the RSC can also indicate the corresponding supported relay hop count. The RSC can be obtained through pre-configuration or based on system messages, and is not limited here.

[0183] Step 702: Relay UE1 receives Discovery Message 1.

[0184] Step 703: Relay UE1 forwards discovery message 2.

[0185] As an example, in this embodiment of the application, the discovery message 2 is obtained by updating the content of discovery message 1. The updated discovery message 2 may carry one or more of the following: the identification information of relay UE3, the RSC, the identification of relay UE1, and the signal quality between relay UE1 and relay UE3 (e.g., SD-RSRP information).

[0186] In one possible approach, relay UE1 can receive discovery message 1 from one or more relay UE3s and select relay UE3s based on the signal quality between relay UE1 and each relay UE3. For example, relay UE3s with signal quality greater than a threshold (e.g., threshold A) are selected. In this case, the discovery message 2 forwarded by relay UE1 carries one or more relay UE3 identifiers greater than threshold A, as well as signal quality information between each relay UE3 greater than threshold A and relay UE1, including one or more of the RSC and the identifier of relay UE1; or...

[0187] Relay UE1 can receive Discover Message 1 from one or more relay UE3s and select a relay UE3 based on the signal quality between relay UE1 and each relay UE3. For example, if the relay UE3 with the best signal quality is selected, then the Discover Message 2 forwarded by relay UE1 carries the identifier of the best relay UE3, as well as the signal quality information between the best relay UE3 and relay UE1, including one or more of the RSC and the identifier of relay UE1; or...

[0188] Relay UE1 can receive discovery message 1 from one or more relay UE3s, carrying all received relay UE3 related information. For example, at this time, the discovery message 2 forwarded by relay UE1 carries one or more relay UE3 identifiers, as well as signal quality information between each relay UE3 and relay UE1, including one or more of the RSC and the identifier of relay UE1.

[0189] Step 704: Relay UE2 receives discovery message 2.

[0190] Step 705: Relay UE2 forwards discovery message 3.

[0191] As an example, in this embodiment of the application, the discovery message 3 can be obtained by updating the content of discovery message 2. The discovery message 3 may carry one or more of the following: the identification information of relay UE3, the RSC, the identification of relay UE1, the identification of relay UE2, the signal quality between relay UE1 and relay UE3, and the signal quality between relay UE1 and relay UE2.

[0192] Step 706: The first terminal device receives discovery message 3.

[0193] Step 707: Based on the discovery message 3, the first terminal device determines the path information for relay service as the first path information.

[0194] As an example, the first path information is selected from one or more path information included in the discovery message 3.

[0195] As an example, before executing step 707 in this embodiment of the application, the first terminal device determines that the path selection condition or the path reselection condition is met. The step of the first terminal device determining that the path selection condition or the path reselection condition is met can be confirmed at any time before step 707.

[0196] Step 708: The first terminal device communicates with the first network device based on the first path information.

[0197] As an example, in this embodiment of the application, the first terminal device carries hop-by-hop relay UE identification information in the PC5 connection establishment request, which is used by the intermediate relay UE to determine the next-hop relay terminal device and trigger the establishment of the PC5 connection.

[0198] In one possible scenario, if a PC5 link has already been established between the relay UEs, the SL-RSRP can be measured directly based on the PC5 link, and the relay UEs can directly forward the User Info ID and SL-RSRP between the relay UEs via PC5 messages; or, if no PC5 connection has been established, the SL-RSRP between the relay UEs can be confirmed based on the obtained messages.

[0199] Using the above method, this application embodiment provides a scenario in model A where a remote UE obtains hop-by-hop relay UE information on a multi-hop relay service path based on a discovery process, and performs relay selection and reselection based on the information, so that the remote UE can select the optimal multi-hop relay path.

[0200] Example 2: In the Model B discovery process scenario, the remote UE obtains relevant information (such as signal quality and relay UE identifier) ​​of all relay UEs on the path based on the discovery process, and uses it to select or reselect relay UEs.

[0201] Figure 8 shows a flowchart of a communication method in this scenario provided by an embodiment of this application. The specific implementation steps can be referred to the following process:

[0202] Step 801: The first terminal device broadcasts a solicitation message 1.

[0203] As an example, in this embodiment of the application, the request message 1 is used to request a relay. The request message 1 may carry the identification information of the first terminal device (e.g., User Info ID), and the discovery message 1 may also carry RSC.

[0204] Step 802: Relay UE2 receives request message 1.

[0205] Step 803: Relay UE2 forwards request message 2.

[0206] As an example, in this embodiment of the application, the request message 2 is obtained by updating the content of the request message 1. The request message 2 may carry one or more of the following: the identifier of the first terminal device, the RSC, the identifier of the relay UE2, the signal quality (e.g., SD-RSRP) between the relay UE2 and the first terminal device, and the hop count information.

[0207] The hop count information can be the number of hops between the first terminal device and the current relay UE2, for example, the hop count information is the number of hops completed.

[0208] In one possible approach, before sending the request message 2, relay UE2 measures the signal quality between the first terminal device and relay UE2 based on the request message 1 received from the first terminal device. If the signal quality is less than a threshold (e.g., threshold B), relay UE2 will not trigger the sending of the request message 2 (default process ends); if the signal quality is greater than threshold B, the process of step 803 is triggered. The threshold B can come from base station configuration, system message configuration, or pre-configuration, or it can be indicated by the first terminal device based on the request message 1, which includes the threshold B, and is not limited here.

[0209] Step 804: Relay UE1 receives request message 2.

[0210] Step 805: Relay UE1 forwards request message 3.

[0211] As an example, in this embodiment of the application, the request message 3 is obtained by updating the content of the request message 2. The updated request message 3 may carry one or more of the following: the identification information of the first terminal device, the RSC, the identification of the relay UE1, the identification of the relay UE2, the signal quality between the relay UE2 and the first terminal device, and the signal quality between the relay UE1 and the relay UE2.

[0212] Similarly, relay UE1 can decide whether to trigger the sending of request message 3 based on the measured signal quality between relay UE1 and relay UE2.

[0213] Step 806: Relay UE3 receives request message 3.

[0214] Step 807: Based on the request message 3, the relay UE3 determines the response message 1.

[0215] As an example, in this embodiment of the application, the response message 1 is obtained by the relay UE3 based on the content of the request message 3.

[0216] The response message 1 may carry one or more of the following: the identification information of the first terminal device, the RSC, the identification of the relay UE1, the identification of the relay UE2, the signal quality between the relay UE2 and the first terminal device, and the signal quality between the relay UE1 and the relay UE2.

[0217] Step 808: Relay UE3 sends response message 1.

[0218] Step 809: Relay UE1 receives response message 1.

[0219] Step 810: Relay UE1 sends response message 2.

[0220] The relay UE1 can determine the next-hop relay terminal device based on the information in the response message 1 and forward the response message 2. For example, the relay UE1 determines to send the response message 2 to the relay UE2 based on the response message 1.

[0221] Optionally, in this embodiment of the application, the relay UE1 may also determine the response message 2 based on the content of the response message 1 and the signal quality between the relay UE1 and the relay UE3.

[0222] Step 811: Relay UE2 receives response message 2.

[0223] Step 812: Relay UE2 sends response message 3.

[0224] Step 813: The first terminal device receives response message 3.

[0225] Step 814: The first terminal device determines the path information for relay service as the first path information based on the response message 3.

[0226] As an example, the first path information is selected from one or more path information included in the response message 3.

[0227] Step 815: The first terminal device communicates with the first network device based on the first path information.

[0228] As an example, in this embodiment of the application, the first terminal device carries hop-by-hop relay UE identification information in the PC5 connection establishment request, which is used by the intermediate relay UE to determine the next-hop UE and trigger the establishment of the PC5 connection.

[0229] As an implementation, the intermediate relay UE will determine whether to select the path and whether to trigger a response message based on the information in the discovery message. That is, each relay UE (including U2N relay UE or intermediate relay UE) may decide whether to trigger a discovery message based on the UE information on the existing path and the signal quality information between UEs before triggering the sending of the discovery message (solicitation message or response message).

[0230] Using the above method, this application embodiment provides a model B scenario in which a remote UE obtains hop-by-hop relay UE information on a multi-hop relay service path based on a U2U relay discovery process, and performs relay selection and reselection based on the information, so that the remote UE can select the optimal multi-hop relay path.

[0231] Example 3: In the case of reusing the same relay terminal for different paths, the first information can carry the path information from multiple first terminal devices (remote UE) to the network device, which is used by the remote UE to select or reselect relay UE.

[0232] For ease of description, as shown in Figure 9, it is assumed that in this embodiment of the application, multiple multi-hop paths can be found through intermediate relay UE3, including:

[0233] Path 1: First terminal device <-> Relay UE3 <-> Relay UE1 <-> U2N Relay UE1

[0234] Path 2: First terminal device <-> Relay UE3 <-> Relay UE1 <-> U2N Relay UE3

[0235] Path 3: First terminal device <-> Relay UE3 <-> Relay UE1 <-> U2N relay UE2

[0236] Path 4: First terminal device <-> Relay UE3 <-> Relay UE2 <-> U2N relay UE3

[0237] For example, when the relay UE3 replies to the first terminal device (remote UE) with a response message or sends a discovery message, it can indicate the information of the above four paths to the remote UE, so that the remote UE can select a path.

[0238] Figure 10 is a schematic flowchart of a communication method in this scenario provided by an embodiment of this application. The specific implementation steps can be referred to the following flowchart:

[0239] Step 1001: Relay UE3 receives second information sent from different relay terminal devices.

[0240] In this embodiment of the application, step 1000 may be included before step 1001. For example, step 1000 may include relay UE1 sending second information to relay UE3, and / or relay UE2 sending second information to relay UE3, etc.

[0241] For example, based on the model B transmission scenario, the relay UE3 may receive response messages from different paths at different times, and the relay UE3 needs to indicate different path information to the same first terminal device at different times.

[0242] For example, relay UE3 receives second information from relay UE1. This second information may be updated information based on the response message. To enable relay UE1 to determine that relay UE3 is used, there are three different path information options. The second information may include multiple path information options, such as the aforementioned path 1 to path 3 that need to be indicated to relay UE3. The second information may be in the form of multiple lists, with each path information corresponding to one list. Each list includes the identification information (e.g., Use Info ID) of one or more relay terminal devices in the corresponding path information, as well as part or all of the signal quality between adjacent relay terminal devices. Alternatively, the second information may include one path information option, and relay UE1 may send second information including different path information to relay UE3 respectively.

[0243] Similarly, relay UE3 can also receive second information sent from relay UE2, the second information including the aforementioned path 4 that needs to be indicated to relay UE3. Specifically, when relay UE1 sends the second information to relay UE3, it can use the L2 ID of relay UE1 as the source L2 ID and the L2 ID of relay UE3 as the destination L2 ID, and then send the second information.

[0244] For example, based on the transmission scenario of model A, relay UE1 can determine multiple paths by receiving announcement messages from U2N relay 1, U2N relay UE2, and U2N relay UE3, and send second information to relay UE3 to indicate the multiple paths. For details, please refer to the introduction of model B above, which will not be repeated here.

[0245] Step 1002: Relay UE3 determines the first information based on the second information.

[0246] Wherein, the first information is used to indicate one or more path information, each path information including information of multiple relay terminal devices, the multiple relay terminal devices providing relay services between the first terminal device and the first network device, the information of the multiple relay terminal devices including the identification information of the multiple relay terminal devices, and / or the signal quality between adjacent relay terminal devices among the multiple relay terminal devices.

[0247] For example, based on the second information received in step 1001, the relay UE3 determines that it needs to indicate the aforementioned paths 1 to 4 to the first terminal device (i.e., the first information includes the relevant content of paths 1 to 4). It is understood that in this embodiment, the relay UE3 can set a threshold C. After receiving second information from a relay terminal device, it starts a timer, the duration of which is set to the threshold C. During the timer's operation, it waits for second information sent by other relay terminal devices. When the timer expires, all second information received within the threshold C duration is integrated to obtain the first information, thereby effectively sharing the system overhead of the first terminal device.

[0248] For example, each time the relay UE3 receives a second piece of information, it directly sends the received second piece of information as the first piece of information to the first terminal device.

[0249] Step 1003: Relay UE3 sends the first information to the first terminal device.

[0250] The relay UE3 sends a response message to the first terminal device. The content of this step 1003 is similar to the sending of the second information described in step 1001 above. For details, please refer to the description of the content of step 1001 above. For example, when indicating multipath information, multipath information can be carried in a single response message, or different path information can be carried in response messages using different L2 IDs, thereby indicating multipath information to the remote UE.

[0251] Step 1004: The first terminal device receives the first information.

[0252] Step 1005: The first terminal device communicates with the network device based on the first message.

[0253] In the scenario based on Example 3, it can also be divided into model A transmission and model B transmission. For the sake of brevity, please refer to the descriptions of Example 1 and Example 2 above for specific details, which will not be repeated here.

[0254] It is understood that, in order to achieve the functions in the above embodiments, the terminal device or network device includes hardware structures and / or software modules corresponding to perform each function. Those skilled in the art should readily recognize that, based on the units and method steps of the various examples described in conjunction with the embodiments disclosed in this application, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware depends on the specific application scenario and design constraints of the technical solution.

[0255] The following are schematic diagrams of possible communication devices provided in the embodiments of this application. These communication devices can be used to implement the functions of terminal devices or network devices in the above method embodiments, and thus can also achieve the beneficial effects of the above method embodiments.

[0256] As shown in Figure 11, the communication device 1100 includes a processing unit 1110 and a communication unit 1120. The communication device 1100 is used to implement the functions of the terminal device or network device in the various method embodiments shown above.

[0257] When the communication device 1100 is used to implement the functions of the first terminal device:

[0258] The communication unit 1120 is configured to receive first information from a second terminal device. The first information is used to indicate one or more path information, each path information including information of multiple relay terminal devices. The multiple relay terminal devices provide relay services between the first terminal device and the first network device. The information of the multiple relay terminal devices includes identification information of the multiple relay terminal devices and / or signal quality between adjacent relay terminal devices among the multiple relay terminal devices. The second terminal device is a relay terminal device among the multiple relay terminal devices that is connected to the first terminal device.

[0259] The processing unit 1110 is used to communicate with the first network device based on the first information.

[0260] In one possible implementation, the processing unit 1110 is specifically used for:

[0261] Based on the first information, a first path information is selected, and communication is performed with the first network device based on the first path information; the first path information is one of the one or more path information.

[0262] In one possible implementation, the processing unit 1110 is specifically used for:

[0263] A connection establishment request is sent to the second terminal device based on the first path information. The connection establishment request includes the identification information of one or more relay terminal devices corresponding to the first path information.

[0264] In one possible implementation, the processing unit 1110 is further configured to:

[0265] Once the first condition is met, the selection of the first path information is triggered.

[0266] In one possible implementation, the first condition includes some or all of the following:

[0267] The first terminal device currently has no serving cell; the signal quality of the serving cell of the first terminal device is less than a first threshold; the first terminal device receives a relay service selection instruction from the upper layer; the signal quality between adjacent relay terminal devices in the relay service is less than a second threshold; a PC5 radio link failure (RLF) exists in the relay service; the first terminal device receives first indication information sent by one or more terminal devices corresponding to the relay service, the first indication information including some or all of the information indicating link abnormality, handover, cell reselection, or PC5 link release; the first terminal device receives a relay service reselection instruction from the upper layer.

[0268] In one possible implementation, the first threshold and the second threshold are determined by one or more of the following methods:

[0269] Based on network device configuration; pre-configured; protocol agreement; specified by the first terminal device.

[0270] In one possible implementation, the processing unit 1110 is further configured to:

[0271] A broadcast request message is used to request a relay service. The request message includes identification information of the first terminal device, indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, and one or more of the number of multiple relay terminal devices supported in the relay service.

[0272] In one possible implementation, the request message includes a first threshold and / or a second threshold.

[0273] In one possible implementation, the first information is carried in a discovery message or a PC5 signaling message.

[0274] When the communication device 1100 is used to implement the functions of the second terminal device:

[0275] Processing unit 1110 is configured to determine first information, which indicates one or more path information, each path information including information of multiple relay terminal devices, the multiple relay terminal devices providing relay services between the first terminal device and the first network device, the information of the multiple relay terminal devices including identification information of the multiple relay terminal devices, and / or signal quality between adjacent relay terminal devices among the multiple relay terminal devices; wherein, the second terminal device is a relay terminal device among the multiple relay terminal devices connected to the first terminal device;

[0276] The communication unit 1120 is used to send the first information to the first terminal device.

[0277] In one possible implementation, the method further includes:

[0278] The system receives a first request message broadcast by the first terminal device. The first request message is used to request a relay service. The first request message includes one or more of the following: identification information of the first terminal device, indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, and the number of multiple relay terminal devices supported in the relay service.

[0279] In one possible implementation, the processing unit 1110 is further configured to:

[0280] Broadcast a second request message; the second request message includes one or more of the following: identification information of the first terminal device, indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, the number of multiple relay terminal devices supported in the relay service, identification information of the second terminal device, and signal quality between the second terminal device and the first terminal device.

[0281] In one possible implementation, the processing unit 1110 is further configured to:

[0282] The signal quality between the second terminal device and the first terminal device is determined to be no less than a third threshold.

[0283] In one possible implementation, the third threshold is determined by one or more of the following methods: based on network device configuration; pre-configured; agreed upon by a protocol; or specified by the first terminal device.

[0284] In one possible implementation, the processing unit 1110 is further configured to:

[0285] The system receives a connection establishment request sent by the first terminal device based on the first path information, establishes a PC5 connection with the first terminal device, wherein the connection establishment request includes the identification information of one or more relay terminal devices corresponding to the first path information, and the first path information is one of the one or more path information; the system determines the next relay terminal device based on the identification information of the one or more relay terminal devices, and sends a connection establishment request to the next relay terminal device.

[0286] When the communication device 1100 is used to implement the function of the first relay terminal device:

[0287] Processing unit 1110 is used to determine second information, the second information including identification information of one or more relay terminal devices, and part or all of the signal quality between adjacent relay terminal devices;

[0288] The communication unit 1120 is used to send the second information to the second relay terminal device; the first relay terminal device and the second relay terminal device provide relay services between the terminal device and the network device.

[0289] In one possible implementation, the one or more relay terminal devices include the first relay terminal.

[0290] In one possible implementation, the second message is carried in a discovery message or a PC5 signaling message.

[0291] In one possible implementation, the processing unit 1110 is specifically used for:

[0292] The second information is sent to the second relay terminal device. The second information includes one or more path information, each path information including the identification information of the one or more relay terminal devices, and part or all of the signal quality between adjacent relay terminal devices.

[0293] In one possible implementation, the processing unit 1110 is specifically used for:

[0294] Send multiple pieces of the second information to the second relay terminal device. Each piece of the second information includes path information, which includes the identification information of the one or more relay terminal devices and part or all of the signal quality between adjacent relay terminal devices.

[0295] In one possible implementation, the processing unit 1110 is further configured to:

[0296] Multiple pieces of the second information are sent to the second relay device using different identifiers; each piece of the second information corresponds to an identifier.

[0297] In one possible implementation, the processing unit 1110 is specifically used for:

[0298] Receive third information sent by a third relay terminal device; when the third information includes the identification information of the third relay terminal device, determine the second information based on one or more of the third information, the identification information of the first relay terminal device, and the signal quality between the first relay terminal device and the third relay terminal device.

[0299] In one possible implementation, the processing unit 1110 is specifically used for:

[0300] Receive third information sent by a third relay terminal device; when the third information includes the identification information of the one or more relay terminal devices, and part or all of the signal quality between adjacent relay terminal devices, determine the second information based on the third information.

[0301] In one possible implementation, the processing unit 1110 is further configured to:

[0302] The system receives a first request message sent by the second relay terminal device. The first request message is used to request a relay service. The request message includes one or more of the following: the identification information of the first terminal device; the indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices; the number of multiple relay terminal devices supported in the relay service; and the identification information of the second relay terminal device.

[0303] In one possible implementation, the processing unit 1110 is further configured to:

[0304] Based on the first request message, the identification information of the first relay terminal device, and the signal quality between the first relay terminal device and the second relay terminal device, a second request message is determined; the second request message is sent to the third relay terminal device. The second request message is used to request relay services. The second request message includes one or more of the following: the identification information of the first terminal device, indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, the number of multiple relay terminal devices supported in the relay service, the identification information of the second relay terminal device, the identification information of the first relay terminal device, and the signal quality between the first relay terminal device and the second relay terminal device.

[0305] In one possible implementation, the processing unit 1110 is further configured to:

[0306] If the signal quality between the first relay terminal device and the third relay terminal device is determined to be no less than a fourth threshold, the second information is sent to the second relay terminal device.

[0307] In one possible implementation, the fourth threshold is determined by one or more of the following methods:

[0308] Based on network device configuration; pre-configured; protocol agreement.

[0309] In one possible implementation, the processing unit 1110 is further configured to:

[0310] Receive the fourth threshold indicated by the first terminal device.

[0311] More detailed descriptions of the processing unit 1110 and the communication unit 1120 can be obtained directly from the relevant descriptions in the above method embodiments, and will not be repeated here.

[0312] It should be understood that the division of units in the above device is merely a logical functional division. In actual implementation, they can be fully or partially integrated into a single physical entity, or they can be physically separated. Furthermore, all units in the device can be implemented entirely through software calls from processing elements; all units can be implemented entirely in hardware; or some units can be implemented through software calls from processing elements, while others are implemented in hardware. For example, each unit can be a separate processing element, or it can be integrated into a chip within the device. Alternatively, it can be stored as a program in memory, called and executed by a processing element of the device. Moreover, these units can be fully or partially integrated together, or implemented independently. The processing element here can also be called a processor, which can be an integrated circuit with signal processing capabilities. In the implementation process, the operations or units described above can be implemented through integrated logic circuits in the processor element or through software calls from processing elements.

[0313] In one example, a unit in any of the above devices can be one or more integrated circuits configured to implement the methods described above, such as: one or more application-specific integrated circuits (ASICs), or one or more digital signal processors (DSPs), or one or more field-programmable gate arrays (FPGAs), or a combination of at least two of these forms of integrated circuits. As another example, when a unit in the device can be implemented in the form of a processing element scheduler, the processing element can be a processor, such as a general-purpose central processing unit (CPU), or other processor capable of calling programs. Furthermore, these units can be integrated together to implement a system-on-a-chip (SOC).

[0314] The receiving unit described above is an interface circuit of the device, used to receive signals from other devices. For example, when the device is implemented as a chip, the receiving unit is an interface circuit for the chip to receive signals from other chips or devices. The transmitting unit described above is an interface circuit of the device, used to transmit signals to other devices. For example, when the device is implemented as a chip, the transmitting unit is an interface circuit for the chip to transmit signals to other chips or devices.

[0315] As another possible product form, the terminal device or network device of this application embodiment can be implemented by a general bus architecture. For ease of explanation, refer to FIG12, which is a schematic diagram of the structure of a communication device 1200 provided in an embodiment of this application. The communication device 1200 includes a processor 1201 and a transceiver 1202. The communication device 1200 can be a terminal device, or a chip or chip system therein; or, the communication device 1200 can be a network device, or a chip or module therein. FIG12 only shows the main components of the communication device 1200. In addition to the processor 1201 and transceiver 1202, the communication device 1200 may further include a memory 1203 and input / output devices (not shown in the figure).

[0316] Optionally, the processor 1201 is mainly used to process communication protocols and communication data, control the entire communication device, execute software programs, and process the data of the software programs. The memory 1203 is mainly used to store software programs and data. The transceiver 1202 may include radio frequency (RF) circuitry and an antenna. The RF circuitry is mainly used for converting baseband signals to RF signals and processing RF signals. The antenna is mainly used for transmitting and receiving RF signals in the form of electromagnetic waves. Input / output devices, such as touchscreens, displays, and keyboards, are mainly used to receive user input data and output data to the user.

[0317] Optionally, the processor 1201, transceiver 1202, and memory 1203 can be connected via a communication bus.

[0318] When the communication device is powered on, the processor 1201 can read the software program in the memory 1203, interpret and execute the instructions of the software program, and process the data of the software program. When data needs to be transmitted wirelessly, the processor 1201 performs baseband processing on the data to be transmitted and outputs the baseband signal to the radio frequency (RF) circuit. The RF circuit processes the baseband signal and transmits the RF signal outward in the form of electromagnetic waves through the antenna. When data is sent to the communication device, the RF circuit receives the RF signal through the antenna, converts the RF signal into a baseband signal, and outputs the baseband signal to the processor 1201. The processor 1201 converts the baseband signal into data and processes the data.

[0319] In another implementation, the radio frequency circuitry and antenna can be set up independently of the processor that performs baseband processing. For example, in a distributed scenario, the radio frequency circuitry and antenna can be arranged remotely, independent of the communication device.

[0320] In some embodiments, those skilled in the art will recognize that the above-described communication device 1100 can take the form of the communication device 1200 shown in FIG12 in terms of hardware implementation.

[0321] As an example, the function / implementation process of the processing unit 1110 in FIG11 can be implemented by the processor 1201 in the communication device 1200 shown in FIG12 calling the computer execution instructions stored in the memory 1203. The function / implementation process of the communication unit 1120 in FIG11 can be implemented by the transceiver 1202 in the communication device 1200 shown in FIG12.

[0322] As another possible product form, the terminal device or network device in this application may adopt the composition structure shown in FIG13, or include the components shown in FIG13. FIG13 is a schematic diagram of the composition of a communication device 1300 provided in this application.

[0323] As shown in Figure 13, the communication device 1300 includes at least one processor 1301. Optionally, the communication device also includes a communication interface 1302.

[0324] When the relevant program instructions are executed in the at least one processor 1301, the device 1300 may implement the methods provided in any of the foregoing embodiments and any of the possible designs therein. Alternatively, the processor 1301 may implement the methods provided in any of the foregoing embodiments and any of the possible designs therein through logic circuits or executable code instructions.

[0325] The communication interface 1302 can be used to receive program instructions and transmit them to the processor, or it can be used for communication interaction between the communication device 1300 and other communication devices, such as exchanging control signaling and / or service data. For example, the communication interface 1302 can be used to receive signals from other devices besides the communication device 1300 and transmit them to the processor 1301, or to send signals from the processor 1301 to other communication devices besides the communication device 1300.

[0326] Optionally, the communication interface 1302 can be a code and / or data read / write interface circuit, or the communication interface 1302 can be a signal transmission interface circuit between a communication processor and a transceiver, or a chip pin.

[0327] Optionally, the communication device 1300 may further include at least one memory 1303, which can be used to store the required program instructions and / or data. It should be noted that the memory 1303 may exist independently of the processor 1301 or may be integrated with the processor 1301. The memory 1303 may be located within or outside the communication device 1300, without limitation.

[0328] Optionally, the communication device 1300 may further include a power supply circuit 1304, which can be used to power the processor 1301. The power supply circuit 1304 may be located in the same chip as the processor 1301, or in a separate chip outside the chip where the processor 1301 is located.

[0329] Optionally, the communication device 1300 may also include a bus, through which the various parts of the communication device 1300 can be interconnected.

[0330] In some embodiments, those skilled in the art will recognize that the communication device 1100 shown in FIG11 can take the form of the communication device 1300 shown in FIG13 in terms of hardware implementation.

[0331] As an example, the function / implementation process of the processing unit 1110 in FIG11 can be implemented by the processor 1301 in the communication device 1300 shown in FIG13 calling the computer execution instructions stored in the memory 1303. The function / implementation process of the communication unit 1120 in FIG11 can be implemented by the communication interface 1302 in the communication device 1300 shown in FIG13.

[0332] It should be noted that the structure shown in Figure 13 does not constitute a specific limitation on the terminal device or network device. For example, in other embodiments of this application, the terminal device or network device may include more or fewer components than shown in the figure, or combine some components, or split some components, or have different component arrangements. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0333] When the aforementioned communication device is a chip applied to a terminal, the terminal chip implements the functions of the terminal in the above method embodiments. The terminal chip receives information from other modules (such as radio frequency modules or antennas) in the terminal, which is information sent to the terminal by the base station; or, the terminal chip sends information to other modules (such as radio frequency modules or antennas) in the terminal, which is information sent to the base station by the terminal.

[0334] When the aforementioned communication device is a module applied to a base station, the base station module implements the functions of the base station in the above method embodiments. The base station module receives information from other modules (such as radio frequency modules or antennas) in the base station, information sent by the terminal to the base station; or, the base station module sends information to other modules (such as radio frequency modules or antennas) in the base station, information sent by the base station to the terminal. Here, the base station module can be the baseband chip of the base station, or a DU (Digital Unit) or other modules. The DU can be a DU under an Open Radio Access Network (O-RAN) architecture.

[0335] It is understood that the processor in the embodiments of this application may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. A general-purpose processor may be a microprocessor or any conventional processor.

[0336] The method steps in the embodiments of this application can be implemented in hardware or by a processor executing software instructions. The software instructions can consist of corresponding software modules, which can be stored in random access memory, flash memory, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, registers, hard disks, portable hard disks, CD-ROMs, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. Alternatively, the ASIC can reside in a base station or terminal. Of course, the processor and storage medium can also exist as discrete components in the base station or terminal.

[0337] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of this application are performed entirely or partially. The computer can be a general-purpose computer, a special-purpose computer, a computer network, a network device, a user equipment, or other programmable device. The computer program or instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, the computer program or instructions can be transferred from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium, such as a floppy disk, hard disk, or magnetic tape; it can also be an optical medium, such as a digital video optical disc; or it can be a semiconductor medium, such as a solid-state drive. The computer-readable storage medium may be a volatile or non-volatile storage medium, or may include both types of storage media.

[0338] In the various embodiments of this application, unless otherwise specified or in case of logical conflict, the terminology and / or descriptions of different embodiments are consistent and can be referenced by each other. The technical features of different embodiments can be combined to form new embodiments according to their inherent logical relationship.

[0339] Based on the same technical concept, embodiments of this application also provide a computer-readable storage medium storing instructions, which may also be referred to as computer programs, computer program code, etc. The instructions, when executed on a computer, cause the computer to perform the functions of the terminal device or network device described in the above method embodiments.

[0340] Based on the same technical concept, this application also provides a computer program product, which includes a computer program or instructions. When the computer program or instructions are run by a communication device, the method steps executed by the terminal device or network device in the above method embodiments are executed.

[0341] Based on the same concept, embodiments of this application also provide a chip, which may include a processor and a memory (or the chip may be coupled to the memory). The chip executes program instructions in the memory to perform the methods executed by the terminal device or network device in the above embodiments. Here, "coupling" refers to two components being directly or indirectly connected to each other; for example, coupling can refer to an electrical connection between two components.

[0342] Based on the same concept, embodiments of this application also provide a communication system, including a first terminal device, a second terminal device, and a third terminal device. The first terminal device is used to implement the functions of the terminal devices in the foregoing embodiments; the second terminal device is used to implement the functions of the second terminal devices in the foregoing embodiments; and the third terminal device is used to implement the functions of the third terminal devices in the foregoing embodiments.

[0343] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, optical storage, etc.) containing computer-usable program code.

[0344] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in one or more blocks of the flowchart illustrations and / or one or more blocks of the block diagrams.

[0345] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means that implement the functions specified in one or more flowcharts and / or one or more block diagrams.

[0346] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A communication method, characterized in that, A chip used in a first terminal device or the first terminal device, comprising: The system receives first information from a second terminal device. The first information is used to indicate one or more path information. Each path information includes information about multiple relay terminal devices. The multiple relay terminal devices provide relay services between the first terminal device and the first network device. The information about the multiple relay terminal devices includes identification information of the multiple relay terminal devices and / or signal quality between adjacent relay terminal devices among the multiple relay terminal devices. The second terminal device is a relay terminal device among the multiple relay terminal devices that is connected to the first terminal device. Based on the first information, communication is established with the first network device.

2. The method according to claim 1, characterized in that, The step of communicating with the first network device based on the first information includes: Based on the first information, select the first path information, and communicate with the first network device based on the first path information; The first path information is one of the one or more path information.

3. The method according to claim 2, characterized in that, The communication with the first network device based on the first path information includes: A connection establishment request is sent to the second terminal device based on the first path information. The connection establishment request includes the identification information of one or more relay terminal devices corresponding to the first path information.

4. The method according to claim 2 or 3, characterized in that, The method further includes: Once the first condition is met, the selection of the first path information is triggered.

5. The method according to claim 4, characterized in that, The first condition includes some or all of the following: The first terminal device currently has no serving cell; the signal quality of the serving cell of the first terminal device is less than a first threshold; the first terminal device receives a relay service selection instruction from the upper layer; the signal quality between adjacent relay terminal devices in the relay service is less than a second threshold; a PC5 radio link failure (RLF) exists in the relay service; the first terminal device receives first indication information sent by one or more terminal devices corresponding to the relay service, the first indication information including some or all of the information indicating link abnormality, handover, cell reselection, or PC5 link release; the first terminal device receives a relay service reselection instruction from the upper layer. The first threshold and the second threshold are determined by one or more of the following methods: Based on network device configuration; pre-configured; protocol agreement; specified by the first terminal device.

6. The method according to any one of claims 1 to 5, characterized in that, The method further includes: A broadcast request message is used to request a relay service. The request message includes identification information of the first terminal device, indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, and one or more of the number of multiple relay terminal devices supported in the relay service.

7. The method according to claim 6, characterized in that, The request message includes a first threshold and / or a second threshold.

8. The method according to any one of claims 1 to 7, characterized in that, The first information is carried in a discovery message or a PC5 signaling message.

9. A communication method, characterized in that, A chip used in a second terminal device or the second terminal device, including: First information is determined, which is used to indicate one or more path information, each path information including information of multiple relay terminal devices, the multiple relay terminal devices providing relay services between the first terminal device and the first network device, the information of the multiple relay terminal devices including identification information of the multiple relay terminal devices, and / or signal quality between adjacent relay terminal devices among the multiple relay terminal devices; wherein, the second terminal device is the relay terminal device among the multiple relay terminal devices that is connected to the first terminal device; Send the first information to the first terminal device.

10. The method according to claim 9, characterized in that, The method further includes: The system receives a first request message broadcast by the first terminal device. The first request message is used to request a relay service. The first request message includes one or more of the following: identification information of the first terminal device, indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, and the number of multiple relay terminal devices supported in the relay service.

11. The method according to claim 10, characterized in that, The method further includes: Broadcast the second request message; The second request message includes one or more of the following: the identification information of the first terminal device; the indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices; the number of multiple relay terminal devices supported in the relay service; the identification information of the second terminal device; and the signal quality between the second terminal device and the first terminal device.

12. The method according to claim 11, characterized in that, The method further includes: Determine that the signal quality between the second terminal device and the first terminal device is not less than a third threshold. The third threshold is determined by one or more of the following methods: Based on network device configuration; pre-configured; protocol agreement; specified by the first terminal device.

13. The method according to any one of claims 9 to 12, characterized in that, The method further includes: Receive a connection establishment request sent by the first terminal device based on the first path information, and establish a PC5 connection with the first terminal device. The connection establishment request includes the identification information of one or more relay terminal devices corresponding to the first path information. The first path information is one of the one or more path information. Based on the identification information of the one or more relay terminal devices, determine the next relay terminal device and send a connection establishment request to the next relay terminal device.

14. A communication method, characterized in that, A chip used in a first relay terminal device or the first relay terminal device, comprising: Determine the second information, which includes identification information of one or more relay terminal devices, and part or all of the signal quality between adjacent relay terminal devices; The second information is sent to the second relay terminal device; the first relay terminal device and the second relay terminal device provide relay services between the terminal device and the network device.

15. The method according to claim 14, characterized in that, The one or more relay terminal devices include the first relay terminal.

16. The method according to claim 14 or 15, characterized in that, The second message is carried in a discovery message or a PC5 signaling message.

17. The method according to any one of claims 14 to 16, characterized in that, Sending the second information to the second relay terminal device includes: The second information is sent to the second relay terminal device. The second information includes one or more path information, each path information including the identification information of the one or more relay terminal devices, and part or all of the signal quality between adjacent relay terminal devices.

18. The method according to any one of claims 14 to 16, characterized in that, Sending the second information to the second relay terminal device includes: Send multiple pieces of the second information to the second relay terminal device. Each piece of the second information includes path information, which includes the identification information of the one or more relay terminal devices and part or all of the signal quality between adjacent relay terminal devices.

19. The method according to claim 18, characterized in that, The method includes: Multiple pieces of the second information are sent to the second relay device using different identifiers; each piece of the second information corresponds to an identifier.

20. The method according to any one of claims 14 to 19, characterized in that, Determining the second information includes: Receive third information sent by a third relay terminal device; When the third information includes the identification information of the third relay terminal device, the second information is determined based on one or more of the third information, the identification information of the first relay terminal device, and the signal quality between the first relay terminal device and the third relay terminal device; or, When the third information includes the identification information of the one or more relay terminal devices, and part or all of the signal quality between adjacent relay terminal devices, the second information is determined based on the third information.

21. The method according to any one of claims 14 to 20, characterized in that, The method further includes: The system receives a first request message sent by the second relay terminal device. The first request message is used to request a relay service. The request message includes one or more of the following: the identification information of the first terminal device; the indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices; the number of multiple relay terminal devices supported in the relay service; and the identification information of the second relay terminal device.

22. The method according to claim 21, characterized in that, The method further includes: Based on the first request message, the identification information of the first relay terminal device, and the signal quality between the first relay terminal device and the second relay terminal device, the second request message is determined; The second request message is sent to the third relay terminal device. The second request message is used to request relay service. The second request message includes the identification information of the first terminal device, the indication information that the first terminal device supports communication with the first network device based on multiple relay terminal devices, the number of multiple relay terminal devices supported in the relay service, the identification information of the second relay terminal device, the identification information of the first relay terminal device, and one or more of the signal quality between the first relay terminal device and the second relay terminal device.

23. The method according to any one of claims 14 to 22, characterized in that, The method further includes: If the signal quality between the first relay terminal device and the third relay terminal device is determined to be no less than a fourth threshold, the second information is sent to the second relay terminal device.

24. The method according to claim 23, characterized in that, The fourth threshold is determined by one or more of the following methods: Based on network device configuration; Pre-configured; As stipulated in the agreement.

25. The method according to claim 23, characterized in that, The method further includes: Receive the fourth threshold indicated by the first terminal device.

26. A communication device, characterized in that, Includes modules or units for performing the method according to any one of claims 1 to 25.

27. A communication device, characterized in that, Includes a processor, the processor being configured to cause the communication device to perform the method of any one of claims 1 to 25.

28. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program or instructions that, when executed on a communication device, cause the communication device to perform the method as described in any one of claims 1 to 25.

29. A computer program product, characterized in that, The computer program product includes a computer program or instructions that, when executed on a communication device, cause the communication device to perform the method as described in any one of claims 1 to 25.

Images