Radio resource control (RRC) connection establishment method and apparatus, and storage medium

Abstract

The present disclosure relates to a radio resource control (RRC) connection establishment method and apparatus, and a storage medium. The method comprises: receiving a first message from a previous-hop node in a first transmission direction; and executing a target operation, wherein the first transmission direction is a transmission direction from a remote terminal to a network device or an uplink transmission direction, and the target operation comprises at least one of the following: establishing an end-to-end RRC connection with the network device; establishing a direct communication interface RRC connection with a third relay terminal, the third relay terminal being a next-hop relay terminal in the first transmission direction; and sending a second message to the third relay terminal by means of a direct communication interface between a first relay terminal and the third relay terminal. By using the method, all or some of relay terminals in a multi-hop relay scenario can be triggered to establish an end-to-end RRC connection with a network device and / or a direct communication interface RRC connection is established between different relay terminals in a multi-hop relay connection.

Description

Radio resource control RRC connection establishment method, device and storage medium CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present disclosure claims priority to Chinese Patent Application No. 2024110000764 entitled "Radio resource control RRC connection establishment method, device and storage medium" filed on July 24, 2024, which is incorporated by reference in its entirety. TECHNICAL FIELD

[0002] The present disclosure relates to the technical field of wireless communication, and in particular, to a radio resource control RRC connection establishment method, device and storage medium. BACKGROUND

[0003] With the development of communication technology, direct communication technology has emerged. The so-called direct communication refers to a technology in which terminals in proximity can perform data transmission within a close range through a direct communication link (also referred to as Sidelink or PC5). In order to expand the coverage range of direct communication, a relay terminal can be introduced. After the introduction of the relay terminal, the terminal that communicates using the relay terminal can be referred to as a remote terminal. In order to further expand the coverage range of the direct communication link, a multi-hop relay scenario can be introduced based on the relay terminal, that is, the remote terminal communicates through multiple relay terminals.

[0004] In the multi-hop relay scenario, one or more of the multiple relay terminals in the multi-hop relay link can be in an RRC (Radio Resource Control) IDLE state or in an INACTIVE state or in an OOC (Out of Coverage) state. In the multi-hop relay link scenario, how to trigger all or part of the relay terminals that are not in an RRC connected state to establish an end-to-end RRC connection state between the network device and the relay terminal and / or to establish a PC5-S / PC5-RRC connection between the first transmission direction and the next hop node is a problem that needs to be solved in the multi-hop relay scenario, where the first transmission direction is the transmission direction of the remote terminal to the network device or the uplink transmission direction. SUMMARY

[0005] Embodiments of the present disclosure provide a radio resource control RRC connection establishment method, device and storage medium.

[0006] In a first aspect, a radio resource control RRC connection establishment method is provided, for a first relay terminal, the method comprising:

[0007] receiving a first message from a previous hop node in a first transmission direction; performing a target operation;

[0008] The first relay terminal is any relay terminal on a multi-hop relay link, the first transmission direction is a transmission direction from a remote terminal to a network device or an uplink transmission direction, and a previous hop node in the first transmission direction is the remote terminal or a second relay terminal. The first message includes at least one of the following: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; data of a wireless link control channel SL-RLC0 bearer specified by a direct communication interface; and the target operation includes at least one of the following: establishing an end-to-end RRC connection with the network device; establishing an RRC connection of a direct communication interface with a third relay terminal, which is a next hop relay terminal in the first transmission direction; and sending a second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal.

[0009] In one of the embodiments, the first message includes identification information of part of the relay terminals on the multi-hop relay link, including: the first message includes identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link; or the first message includes identification information of the first relay terminal and identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link.

[0010] In one of the embodiments, the establishment of the end-to-end RRC connection with the network device includes any of the following: establishing an end-to-end RRC connection with the network device through a Uu interface between the first relay terminal and the network device; and establishing an end-to-end RRC connection with the network device through a multi-hop relay mode.

[0011] In one of the embodiments, the establishment of the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device includes: if the first relay terminal is an in-network terminal, and the first relay terminal is in an RRC idle state or an RRC inactive state, establishing an end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device.

[0012] In one of the embodiments, the establishing the end-to-end RRC connection with the network device through the multi-hop relay mode comprises at least one of the following: establishing a direct communication interface RRC connection with the third relay terminal; sending the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal; and sending an end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode.

[0013] In one of the embodiments, the second message comprises at least one of the following information: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; and data carried by the SL-RLC0.

[0014] In one of the embodiments, the second message comprises identification information of part of the relay terminals on the multi-hop relay link, which comprises: the second message comprises identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link; or the second message comprises identification information of the third relay terminal and identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link.

[0015] In one of the embodiments, the sending the end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode comprises: if a first condition is met, sending the end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode; wherein the first condition comprises: each relay terminal between the first relay terminal and the network device on the multi-hop relay link has established an end-to-end RRC connection with the network device; and there is a direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal.

[0016] In one of the embodiments, the establishing the direct communication interface RRC connection between the first relay terminal and the third relay terminal comprises: if there is no direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal, establishing a direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal.

[0017] In one of the embodiments, the sending the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal comprises: if a second condition is satisfied, sending the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal; and the second condition comprises at least one of the following: there is a direct communication interface connection between the first relay terminal and the third relay terminal; the third relay terminal is in an RRC idle state or in an inactive state or in a disconnection state; there is no end-to-end RRC connection between the third relay terminal and the network device; there is no direct communication interface connection between the third relay terminal and a next-hop relay terminal of the third relay terminal in the first transmission direction; at least one relay terminal between the first relay terminal and the network device on the multi-hop relay link is in an RRC idle state or in an RRC inactive state or in a disconnection state.

[0018] In one of the embodiments, the method further comprises: receiving a third message, the third message carrying an end-to-end RRC connection state between at least one relay terminal on the multi-hop relay link and a network device and / or a direct communication interface PC5-RRC connection state between relay terminals.

[0019] In one of the embodiments, the third message comprises at least one of the following: a relay discovery related message; a PC5-RRC message.

[0020] In a second aspect, an RRC connection establishment apparatus is provided, configured for a first relay terminal, the first relay terminal being any relay terminal on a multi-hop relay link, and the apparatus comprising:

[0021] a receiving unit, configured to receive a first message from a previous-hop node in a first transmission direction;

[0022] a performing unit, configured to perform a target operation;

[0023] The first relay terminal is any relay terminal on a multi-hop relay link, the first transmission direction is a transmission direction of a remote terminal to a network device or an uplink transmission direction, and a previous hop node in the first transmission direction is the remote terminal or a second relay terminal. The first message includes at least one of the following: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; data of a wireless link control channel SL-RLC0 bearer specified through a direct communication interface; and the target operation includes at least one of the following: establishing an end-to-end RRC connection with the network device; establishing a direct communication interface RRC connection with a third relay terminal, which is a next hop relay terminal in the first transmission direction; and sending a second message to the third relay terminal through a direct communication interface between the first relay terminal and the third relay terminal.

[0024] In a third aspect, a first relay terminal is provided, the first relay terminal being any relay terminal on a multi-hop relay link, comprising a memory, a transceiver, and a processor.

[0025] The memory is configured to store a computer program; the transceiver is configured to transceive data under control of the processor; and the processor is configured to read the computer program in the memory and perform the following operations:

[0026] The transceiver is controlled to receive a first message from a previous hop node in a first transmission direction; and a target operation is performed. The first transmission direction is a transmission direction of a remote terminal to a network device or an uplink transmission direction, and the previous hop node in the first transmission direction is the remote terminal or a second relay terminal. The first message includes at least one of the following: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; data of a wireless link control channel SL-RLC0 bearer specified through a direct communication interface; and the target operation includes at least one of the following: establishing an end-to-end RRC connection with the network device; establishing a direct communication interface RRC connection with a third relay terminal, which is a next hop relay terminal in the first transmission direction; and sending a second message to the third relay terminal through a direct communication interface between the first relay terminal and the third relay terminal.

[0027] In one of the embodiments, the first message includes identification information of part of the relay terminals on the multi-hop relay link, including: the first message includes identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link; or, the first message includes identification information of the first relay terminal and identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link.

[0028] In one of the embodiments, the establishing of the end-to-end RRC connection with the network device includes any of the following: controlling the transceiver to establish the end-to-end RRC connection with the network device through a Uu interface between the first relay terminal and the network device; and controlling the transceiver to establish the end-to-end RRC connection with the network device through a multi-hop relay mode.

[0029] In one of the embodiments, the controlling of the transceiver to establish the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device includes: if the first relay terminal is an in-network terminal, and the first relay terminal is in an RRC idle state or an RRC inactive state, controlling the transceiver to establish the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device.

[0030] In one of the embodiments, the controlling of the transceiver to establish the end-to-end RRC connection with the network device through the multi-hop relay mode includes at least one of the following: controlling the transceiver to establish a direct communication interface RRC connection with the third relay terminal; controlling the transceiver to send the second message to the third relay terminal through a direct communication interface between the first relay terminal and the third relay terminal; and controlling the transceiver to send, to the network device, a request for establishing an end-to-end RRC connection between the first relay terminal and the network device through the multi-hop relay mode.

[0031] In one of the embodiments, the second message includes at least one of the following information: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of each relay terminal and the remote terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; and data carried by an SL-RLC0.

[0032] In one of the embodiments, the second message comprises identification information of the partial relay terminals on the multi-hop relay link, including: the second message comprises identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link; or, the second message comprises identification information of the third relay terminal and identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link.

[0033] In one of the embodiments, the control of the transceiver to send the end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode comprises: if a first condition is met, controlling the transceiver to send the end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode; wherein the first condition comprises: each relay terminal between the first relay terminal and the network device on the multi-hop relay link has established an end-to-end RRC connection with the network device; and there is a direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal.

[0034] In one of the embodiments, the control of the transceiver and the third relay terminal to establish a direct communication interface RRC connection comprises: if there is no direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal, controlling the transceiver and the third relay terminal to establish a direct communication interface PC5-RRC connection.

[0035] In one of the embodiments, the control of the transceiver to send the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal comprises: if a second condition is met, controlling the transceiver to send the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal; wherein the second condition comprises at least one of the following: there is a direct communication interface connection between the first relay terminal and the third relay terminal; the third relay terminal is in an RRC idle state or in an inactive state or in an off-network state; there is no end-to-end RRC connection between the third relay terminal and the network device; there is no direct communication interface connection between the third relay terminal and the next-hop relay terminal of the third relay terminal in the first transmission direction; at least one relay terminal between the first relay terminal and the network device on the multi-hop relay link is in an RRC idle state or an RRC inactive state or in an off-network state.

[0036] In one of the embodiments, the processor is further configured to control the transceiver to receive a third message, the third message carrying a state of an end-to-end RRC connection between at least one relay terminal and a network device over the multi-hop relay link and / or a state of a direct communication interface PC5-RRC connection between relay terminals.

[0037] In one of the embodiments, the third message comprises at least one of the following: a relay discovery related message; a PC5-RRC message.

[0038] In a fourth aspect, a processor readable storage medium is provided, which stores a program for causing a processor to perform the method of any one of the first aspect.

[0039] The above description is merely a summary of the technical solutions of the present disclosure. In order to enable one of ordinary skill in the art to better understand the technical means of the present disclosure and implement it according to the contents of the description, and in order to enable the above and other purposes, characteristics and advantages of the present disclosure to be more apparent, the specific implementation manner of the present disclosure is described below. BRIEF DESCRIPTION OF DRAWINGS

[0040] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the embodiments. The accompanying drawings are merely schematic and are not intended to be limiting of the present disclosure. Like reference numerals are intended to represent like parts throughout the various drawings. In the drawings:

[0041] FIG. 1 is a schematic diagram of a communication mode based on a cellular network in an LTE system;

[0042] FIG. 2 is a schematic diagram of a communication mode of direct communication;

[0043] FIG. 3 is a schematic diagram of a communication mode in a single-hop relay scenario;

[0044] FIG. 4 is a schematic diagram of a communication mode in a multi-hop relay scenario;

[0045] FIG. 5 is a schematic diagram of a flow of an RRC connection establishment method in one embodiment of the present disclosure;

[0046] FIG. 6 is a block diagram of a structure of an RRC connection establishment apparatus in one embodiment of the present disclosure;

[0047] FIG. 7 is a schematic diagram of a structure of a first relay terminal in one embodiment of the present disclosure;

[0048] FIG. 8 is a schematic diagram of a structure of a chip in one embodiment of the present disclosure. DETAILED DESCRIPTION

[0049] In order to make the purposes, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present disclosure and not intended to limit the present disclosure.

[0050] The conventional wireless communication adopts a cellular network, and a terminal and a network device (e.g., a base station) perform uplink / downlink data / control information transmission through a Uu interface.

[0051] Referring to FIG. 1, FIG. 1 is a schematic diagram of a communication mode in a LTE (Long Term Evolution) system. The UE (User Equipment) 1 and the UE 2 shown in FIG. 1 are different terminals, and the UE 1 and the UE 2 are respectively connected to a network device through a Uu interface, i.e., the UE 1 and the UE 2 respectively establish a Uu link with the network device through the Uu interface. The network device shown in FIG. 1 is a base station, and the base station is connected to a core network (CN).

[0052] Referring to FIG. 2, FIG. 2 is a schematic diagram of a communication mode of direct communication. Based on the communication mode shown in FIG. 1, FIG. 2 shows that the UE 1 and the UE 2 can also perform direct communication through a Sidelink interface.

[0053] Direct communication refers to a mode in which terminals close to each other can perform data transmission in a short distance range through a direct communication link. The direct communication link is also referred to as a Sidelink, a PC5 (Proximity Communication Port 5) or a sidelink. The wireless interface corresponding to the direct communication link is also referred to as a direct communication interface, a Sidelink interface, a PC5 interface or a sidelink interface. In order to expand the network coverage, the concept of relay is introduced, and the relay can be a terminal with a relay function.

[0054] For a UE-to-Network Relay (U2N Relay), the interface between the relay terminal and the network device uses a Uu interface, and the interface between the relay terminal and the relayed terminal (hereinafter referred to as a remote terminal) uses a Sidelink interface (also referred to as a direct communication interface, a sidelink interface or a PC5 interface as described above).

[0055] Referring to FIG. 3, FIG. 3 is a schematic diagram of a communication mode in a single-hop relay scenario. The so-called "single-hop" means that the remote terminal shown in FIG. 3 can be connected to the network device through one relay terminal.

[0056] If the remote terminal cannot connect to the network device through a relay terminal, it is necessary to consider using multi-hop relay. In the multi-hop relay scenario, the remote terminal connects to the network device through a multi-hop relay link formed by two or more relay terminals.

[0057] For example, referring to FIG. 4, which is a schematic diagram of a communication mode in a multi-hop relay scenario. The multi-hop relay link shown in FIG. 4 includes relay terminal 1, relay terminal 2, and relay terminal 3. Relay terminals that do not have a direct connection with the network device (such as relay terminal 1 and relay terminal 2) can also be referred to as immediate relays, or U2U (UE-to-UE) relays according to their location, or U2N relays according to their function of assisting remote terminals to access the network.

[0058] In the multi-hop relay scenario, how to trigger all or part of the relay terminals on the multi-hop relay link that are not in the RRC connected state to establish an end-to-end RRC connected state with the network device and / or establish a PC5-S / PC5-RRC connection between the next hop node in the first transmission direction is a problem that needs to be solved urgently in the multi-hop relay scenario.

[0059] In the multi-hop relay scenario, how to trigger all or part of the relay terminals on the multi-hop relay link that are not in the RRC connected state to establish an end-to-end RRC connected state with the network device and / or establish a PC5-S / PC5-RRC connection between the next hop node in the first transmission direction is a problem that needs to be solved urgently in the multi-hop relay scenario.

[0060] Among them, the terminal device (such as a remote terminal, a relay terminal on a multi-hop relay link) involved in the embodiments of the present disclosure can be a device that provides voice and / or data connectivity to a user, a handheld device with wireless connection function, or other processing devices connected to a wireless modem, etc. In different systems, the name of the terminal device may also be different, for example, in the 5G system or the 6G system, the terminal device can be called user equipment (User Equipment, UE). The wireless terminal device can be a USB storage device, other personal computer memory devices and a dongle, and can also communicate with one or more core networks (Core Network, CN) through a radio access network (Radio Access Network, RAN). The wireless terminal device can be a mobile terminal device, such as a mobile phone (or called "cellular" phone) and a computer with a mobile terminal device, for example, it can be a portable, pocket-sized, handheld, computer-built or vehicle-mounted mobile device that exchanges language and / or data with a radio access network. For example, personal communication service (Personal Communication Service, PCS) phones, cordless phones, session initiation protocol (Session Initiated Protocol, SIP) phones, wireless local loop (Wireless Local Loop, WLL) stations, personal digital assistants (Personal Digital Assistant, PDA), personal computers, tablet computers, machine type communication (Machine-type Communication, MTC) terminal devices, etc. The wireless terminal device can also be called a system, a subscriber unit, a subscriber station, a mobile station, a mobile, a remote station, an access point, a remote terminal, an access terminal, a user terminal, a user agent, a user device, and a wireless access device and router / modem that meet the limitations of the present definition, etc. The embodiments of the present disclosure are not limited.

[0061] The network device related to the embodiments of the present disclosure can be a base station, which can include a plurality of cells serving terminals. According to different application scenarios, the base station can also be referred to as an access point, or can be a device in an access network that communicates with wireless terminal devices through one or more sectors over an air interface, or other names. The network device can be used to exchange received air frames and Internet Protocol (IP) packets as a router between the wireless terminal device and the rest of the access network, which can include an Internet Protocol (IP) communication network. The network device can also coordinate the management of the properties of the air interface. For example, the network device related to the embodiments of the present disclosure can be an evolved network device (eNB or e-NodeB) in a long-term evolution (LTE) system, a 5G base station (gNB) in a 5G network architecture, etc., and can also be a home evolved base station (HeNB), a relay node, a femto, a pico, a network test device, etc., which is not limited in the embodiments of the present disclosure. In some network structures, the network device can include a centralized unit (CU) node and a distributed unit (DU) node, and the centralized unit and the distributed unit can also be arranged geographically apart.

[0062] The technical solutions of the present disclosure and how the technical solutions of the present disclosure solve the above technical problems will be described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes can not be described again in some embodiments. The embodiments of the present disclosure will be described below with reference to the drawings.

[0063] In one embodiment, as shown in FIG. 5, an RRC connection establishment method is provided, which is described by applying the method to a first relay terminal, including the following steps:

[0064] Step 501, the first relay terminal receives a first message from a previous hop node in a first transmission direction.

[0065] Wherein, the first relay terminal is any relay terminal in a multi-hop relay link, and the first transmission direction is a transmission direction from a remote terminal to a network device or an uplink transmission direction. It should be noted that the "transmission direction from a remote terminal to a network device" and the "uplink transmission direction" are actually the same transmission method, only the expression is different.

[0066] Please refer to FIG. 4, which is an exemplary multi-hop relay link including 3 relay terminals, in which the first relay terminal is any one of the 3 relay terminals, i.e., the first relay terminal can be relay terminal 1, relay terminal 2 or relay terminal 3 in FIG. 4, and the first transmission direction is the direction from the remote terminal to the network device in the figure.

[0067] In the multi-hop relay link, the last hop node of the first relay terminal in the first transmission direction can be the remote terminal or another relay terminal. For the convenience of description, the other relay terminal is referred to as the second relay terminal in the embodiments of the present disclosure. Please continue to refer to FIG. 4, if the first relay terminal is relay terminal 1 in FIG. 4, the last hop node thereof in the first transmission direction is the remote terminal, if the first relay terminal is relay terminal 2 in FIG. 4, the last hop node thereof in the first transmission direction is relay terminal 1 (which is referred to as the second relay terminal at this time), and if the first relay terminal is relay terminal 3 in FIG. 4, the last hop node thereof in the first transmission direction is relay terminal 2 (which is referred to as the second relay terminal at this time).

[0068] In optional embodiments of the present disclosure, the first message includes at least one of the following: 1, identification information of the multi-hop relay link (for example, connection for Multi-hop); 2, identification information of the multi-hop relay link; 3, identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; 4, identification information of all or part of the relay terminals on the multi-hop relay link; 5, data carried by the SL-RLC0 (direct communication interface designated wireless link control channel).

[0069] In optional embodiments of the present disclosure, the first message can be a PC5-RRC message or a PC5-S message, and of course, a new PC5-S message or PC5-RRC message can also be used. In some embodiments, if the first message is a PC5-RRC message and the first message contains “identification information of the multi-hop relay link”, the first message can use the existing RemoteUEInformationSidelink message, in which the connectionforMultipleHop field needs to be added, which can be Option (optional) or use 1 bit. If the field is optional, the appearance of the field indicates that the first relay terminal needs to be triggered to establish an RRC connection. If the field is 1 bit, the value of the bit, such as 1, can be used to indicate that the first relay terminal needs to be triggered to establish an RRC connection.

[0070] Step 502, the first relay terminal performs a target operation.

[0071] The receiving of the first message can trigger the first relay terminal to perform a target operation, wherein the target operation comprises at least one of the following: 1. establishing a direct communication interface RRC connection with a third relay terminal, wherein the third relay terminal is a next-hop relay terminal in the first transmission direction; 2. sending a second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal; and 3. establishing an end-to-end RRC connection with a network device.

[0072] In optional embodiments of the present disclosure, the second message comprises at least one of the following information: 1. identification information of the established multi-hop relay link; 2. identification information of the multi-hop relay link; 3. identification information of each relay terminal and identification information of a remote terminal on the multi-hop relay link; 4. identification information of all or part of the relay terminals on the multi-hop relay link; and 5. data carried by the SL-RLC0.

[0073] It should be noted that the first message and the second message can be the same message, or can be different messages, and the information included in the first message can be the same as or different from the information included in the second message.

[0074] Similarly to the first message, in optional embodiments of the present disclosure, the second message can be a PC5-RRC message or a PC5-S message, and of course, a new PC5-S message or a PC5-RRC message can also be used. In some embodiments, if the second message is a PC5-RRC message and the second message contains “identification information of the established multi-hop relay link”, the second message can use the existing RemoteUEInformationSidelink message, wherein the connectionforMultipleHop field needs to be added, and the field can be Option (optional) or use 1 bit. As described above, if the field is optional, the appearance of the field indicates that the third relay terminal needs to be triggered to establish an RRC connection. If the field is 1 bit, the value of the bit, such as 1, can be used to indicate that the third relay terminal needs to be triggered to establish an RRC connection.

[0075] In actual applications, the status of the multi-hop relay link is very diverse. For example, one or more relay terminals in the multi-hop relay link can be in IDLE / INACTVE / OOC, and there can be no direct communication interface PC5-RRC connection between some adjacent relay terminals in the multi-hop relay link.

[0076] Please refer back to FIG. 4, in one possible multi-hop relay link situation, relay terminal 1 and relay terminal 2 are in IDLE / INACTIVE / OOC, relay terminal 3 is in RRC connected state, that is, there is an end-to-end RRC connection between relay terminal 3 and the network device, at the same time, there is no direct communication interface PC5-RRC connection between relay terminal 2 and relay terminal 3. Of course, the reader should understand that this one possible multi-hop relay link situation is one example of a variety of multi-hop relay link situations.

[0077] It is precisely because the multi-hop relay link situation is very diverse, how to design a way to adapt to the diverse multi-hop relay link situation, and to trigger all relay terminals in the multi-hop relay link that are not in the RRC connected state to enter the end-to-end RRC connected state with the network device and / or establish PC5-S / PC5-RRC connection between the next hop node in the first transmission direction is a very challenging task, where "triggering all relay terminals in the multi-hop relay link that are not in the RRC connected state to enter the end-to-end RRC connected state with the network device and / or establish PC5-S / PC5-RRC connection between the next hop node in the first transmission direction" can be understood in some embodiments as triggering all relay terminals in the multi-hop relay link that are not in the RRC connected state to enter the end-to-end RRC connected state with the network device and / or establish PC5-S / PC5-RRC connection between the next hop node in the first transmission direction.

[0078] The RRC connection establishment method provided by the embodiments of the present disclosure can transmit a trigger message hop by hop along the first transmission direction in the multi-hop relay link, that is, the first message and the second message described above, where the first message can be understood as a trigger message received by a relay terminal on the multi-hop relay link from the previous hop node in the first transmission direction, and the second message can be understood as a trigger message sent by a relay terminal on the multi-hop relay link to the next hop relay terminal in the first transmission direction. According to the above description of the first message and the second message, it can be known that the trigger messages transmitted between different adjacent hop nodes of the multi-hop relay link can be the same or different in the embodiments of the present disclosure.

[0079] After receiving the trigger message, the relay terminal in the multi-hop relay link can select one or more of the three different types of target operations according to the situation of the multi-hop relay link (which can include the situation of the relay terminal itself receiving the trigger message, the situation of other relay terminals). In this way, all relay terminals in the multi-hop relay link that are not in the RRC connected state can eventually enter the end-to-end RRC connected state with the network device and / or establish PC5-S / PC5-RRC connection between the next hop node in the first transmission direction.

[0080] It should be noted that, in some embodiments, the hop-by-hop transmission trigger message does not mean that each relay terminal on the multi-hop relay link can receive the trigger message, and in some cases, a relay terminal at a next hop or several next hops in the first transmission direction can not receive the trigger message, which is related to the type of target operation selected by the previous hop relay terminal of the relay terminal at the next hop or several next hops to perform, that is, if the target operation performed by the previous hop relay terminal of the relay terminal at the next hop or several next hops does not include sending the trigger message, then the relay terminal at the next hop or several next hops in the first transmission direction does not receive the trigger message, in other words, if the first relay terminal in the embodiments of the present disclosure is the previous hop relay terminal of the relay terminal at the next hop or several next hops, and the first relay terminal triggers the execution of the target operation after receiving the first message, but the target operation performed by the first relay terminal does not include "sending the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal", then the relay terminal at the next hop or several next hops does not receive the trigger message.

[0081] As described above, the first message can include the identification information of part of the relay terminals on the multi-hop relay link, and in optional embodiments of the present disclosure, the first message includes the identification information of part of the relay terminals on the multi-hop relay link, including the following two possible cases:

[0082] 1. The first message includes the identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link, for example, referring to FIG. 4, assuming that the first relay terminal is relay terminal 2 in FIG. 4, the first message can include the identification information of each relay terminal between relay terminal 2 and the network device, that is, the identification information of relay terminal 3.

[0083] 2. The first message includes the identification information of the first relay terminal and the identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link, for example, referring to FIG. 4, assuming that the first relay terminal is relay terminal 2 in FIG. 4, the first message can include the identification information of relay terminal 2 and the identification information of each relay terminal between relay terminal 2 and the network device, that is, the identification information of relay terminal 2 and the identification information of relay terminal 3.

[0084] Similarly, as described above, the second message can include the identification information of part of the relay terminals on the multi-hop relay link, and in optional embodiments of the present disclosure, the second message includes the identification information of part of the relay terminals on the multi-hop relay link, including the following two possible cases:

[0085] 1、the second message includes the identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link, for example, referring to FIG. 4, assuming that the first relay terminal is the relay terminal 1 in FIG. 4 and the third relay terminal is the relay terminal 2 in FIG. 4, the first message can include the identification information of each relay terminal between the relay terminal 2 and the network device, that is, the identification information of the relay terminal 3.

[0086] 2、the second message includes the identification information of the third relay terminal and the identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link, for example, referring to FIG. 4, assuming that the first relay terminal is the relay terminal 1 in FIG. 4 and the third relay terminal is the relay terminal 2 in FIG. 4, the first message can include the identification information of the relay terminal 2 and the identification information of each relay terminal between the relay terminal 2 and the network device, that is, the identification information of the relay terminal 2 and the identification information of the relay terminal 3.

[0087] After the first message and the second message are described, the three different types of target operations described above will be described respectively by the embodiments of the present disclosure.

[0088] The first target operation: the first relay terminal and the third relay terminal establish a direct communication interface RRC connection, wherein the third relay terminal is the next hop relay terminal in the first transmission direction.

[0089] In the optional embodiments of the present disclosure, the first relay terminal can establish a direct communication interface RRC connection with the third relay terminal if the condition of the multi-hop relay link meets certain conditions, specifically, if there is no direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal, the first relay terminal and the third relay terminal establish a direct communication interface PC5-RRC connection.

[0090] The second target operation: the first relay terminal sends the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal.

[0091] Similarly, in optional embodiments of the present disclosure, the first relay terminal can send the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal if the condition of the multi-hop relay link meets a certain condition, specifically, the first relay terminal sends the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal if a second condition is met. The second condition includes at least one of the following: 1. There is a direct communication interface connection between the first relay terminal and the third relay terminal; 2. The third relay terminal is in an RRC idle state (IDLE) or in an inactive state (INACTVE) or in an off-network state (OOC); 3. There is no end-to-end RRC connection between the third relay terminal and the network device; 4. There is no direct communication interface connection between the third relay terminal and the next-hop relay terminal of the third relay terminal in the first transmission direction; 5. At least one relay terminal between the first relay terminal and the network device on the multi-hop relay link is in an RRC idle state (IDLE) or an RRC inactive state (INACTVE) or in an off-network state (OOC).

[0092] It should be noted that if the target operation performed by the first relay terminal includes "sending the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal", the third relay terminal will receive the trigger message (i.e. the second message). Since the first relay terminal is any relay terminal on the multi-hop relay link, at this time, the third relay terminal can be understood as the first relay terminal in fact, and the third relay terminal receiving the second message can be understood as receiving the first message by the first relay terminal in fact. Further, the third relay terminal can also perform the target operation as described above after receiving the second message.

[0093] The third target operation: the first relay terminal and the network device establish an end-to-end RRC connection. The first relay terminal and the network device establishing an end-to-end RRC connection can include any of the following: 1. The first relay terminal establishes an end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device. 2. The first relay terminal establishes an end-to-end RRC connection with the network device through a multi-hop relay mode.

[0094] Please refer to FIG. 4, as shown in FIG. 4, for the relay terminal, the establishment of the end-to-end RRC connection with the network device can include: if there is a direct Uu interface connection between the relay terminal and the network device, establishing the end-to-end RRC connection with the network device through the Uu interface between the relay terminal and the network device; if there is no direct Uu interface connection between the relay terminal and the network device, the establishment of the end-to-end RRC connection with the network device can include: establishing the end-to-end RRC connection with the network device through the multi-hop relay mode, and the so-called "establishing the end-to-end RRC connection with the network device through the multi-hop relay mode" refers to establishing the end-to-end RRC connection with the network device through other relay terminals and the network device between the relay terminal and the network device.

[0095] In the above, the establishment of the end-to-end RRC connection between the first relay terminal and the network device through the Uu interface between the first relay terminal and the network device needs to meet certain conditions, specifically, if the first relay terminal is an in-network terminal, and the first relay terminal is in the RRC idle state (IDLE) or the RRC inactive state (INACTVE), the first relay terminal can establish the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device.

[0096] The establishment of the end-to-end RRC connection between the relay terminal and the network device through the multi-hop mode includes: 1, establishing a direct communication interface RRC connection with a third relay terminal; 2, sending a second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal; 3, sending an end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode.

[0097] In the above, similar to the above, in the optional embodiments of the present disclosure, the first relay terminal can establish a direct communication interface RRC connection with a third relay terminal if the conditions of the multi-hop relay link meet certain conditions, specifically, if there is no direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal, the first relay terminal and the third relay terminal establish a direct communication interface PC5-RRC connection.

[0098] Additionally, similar to the above, in optional embodiments of the present disclosure, the first relay terminal can send the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal if the condition of the multi-hop relay link meets a certain condition, specifically, the first relay terminal sends the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal if the second condition is met. The second condition includes at least one of the following: 1. There is a direct communication interface connection between the first relay terminal and the third relay terminal; 2. The third relay terminal is in an RRC idle state (IDLE) or in an inactive state (INACTVE) or in an off-network state (OOC); 3. There is no end-to-end RRC connection between the third relay terminal and the network device; 4. There is no direct communication interface connection between the third relay terminal and the next-hop relay terminal of the third relay terminal in the first transmission direction; 5. At least one relay terminal between the first relay terminal and the network device on the multi-hop relay link is in an RRC idle state or an RRC inactive state or in an off-network state.

[0099] In addition, the first relay terminal can send an end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode if the condition of the multi-hop relay link meets a certain condition, specifically, the first relay terminal sends the end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode if the first condition is met, wherein the first condition includes: 1. Each relay terminal between the first relay terminal and the network device on the multi-hop relay link has established an end-to-end RRC connection with the network device; 2. There is a direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal.

[0100] According to the above, in the process of the first relay terminal determining which of the three types of target operations it needs to perform, the first relay terminal may need to obtain the end-to-end RRC connection state between the relay terminal and the network device and / or the direct communication interface PC5-RRC connection state between the relay terminals.

[0101] To this end, a third message can be exchanged on the multi-hop relay link, wherein the third message carries the end-to-end RRC connection state between at least one relay terminal on the multi-hop relay link and the network device and / or the direct communication interface PC5-RRC connection state between the relay terminals. The first relay terminal can receive the third message.

[0102] In optional embodiments of the present disclosure, the third message can include at least one of the following: 1. a relay discovery related message; 2. a PC5-RRC message. The relay discovery related message may, for example, include a Relay discovery announcement message, a Relay discovery solicitation message, and a relay discovery solicitation response message. The PC5-RRC message may, for example, include a RemoteUEInformationSidelink message.

[0103] To facilitate the reader's understanding of the technical solutions provided by the embodiments of the present disclosure, the present disclosure will be described below with two embodiments taking the multi-hop relay link shown in FIG. 4 as an example.

[0104] Embodiment 1:

[0105] Suppose the remote terminal uses Model A to perform relay discovery and relay selection, in which case triggering all or part of the relay terminals in the multi-hop relay link to enter the RRC connected state includes the following steps:

[0106] Step 1: The remote terminal receives a Relay Discovery Announcement message from one or more relay terminals.

[0107] The Relay Discovery Announcement message can reuse the Relay Discovery Announcement message of Rel-17 U2N relay, while adding a Hop-Count parameter with a value of 1, indicating that the relay terminal supports multi-hop.

[0108] Step 2: The remote terminal performs multi-hop relay link selection and selects relay terminal 1.

[0109] If the remote terminal can only receive a Relay Discovery Announcement message sent by one relay terminal in step 1, and the direct communication interface channel quality (such as SD-RSRP) between the remote terminal and the relay terminal is higher than or equal to a threshold, the remote terminal can directly select the relay terminal as relay terminal 1 or select the multi-hop relay link corresponding to the relay terminal.

[0110] If the remote terminal can receive the Relay Discovery Announcement messages sent by multiple relay terminals in step 1, and the direct communication interface channel quality between the remote terminal and the multiple relay terminals are all higher than or equal to a threshold, a relay terminal can be randomly selected from the multiple relay terminals as the relay terminal 1 or a multi-hop relay link corresponding to a relay terminal is randomly selected.

[0111] Step 3, the remote terminal and the relay terminal 1 establish a direct communication interface connection.

[0112] The direct communication interface connection includes a PC5-S connection and / or a PC5-RRC connection.

[0113] Step 4, the remote terminal sends a first message to the relay terminal 1 through the direct communication interface.

[0114] The first message is a trigger message. The first message includes at least one of the following: 1, identification information of the multi-hop relay link (such as connection for Multi-hop); 2, data carried by the SL-RLC0 bearer. The first message can be a PC5-RRC or PC5-S message.

[0115] Step 5, the relay terminal 1 performs a target operation.

[0116] The target operation includes at least one of the following: 1, establishing an end-to-end RRC connection with the network device; 2, establishing a direct communication interface RRC connection with the relay terminal 2; 3, sending a second message to the relay terminal 2 through the direct communication interface between the relay terminal 1 and the relay terminal 2.

[0117] The “establishing an end-to-end RRC connection with the network device” includes: establishing an end-to-end RRC connection with the network device through a multi-hop relay mode.

[0118] If the relay terminal 1 needs to establish an end-to-end RRC connection with the network device through a multi-hop relay mode, if at least one relay terminal between the multi-hop relay and the network device does not have a PC5-S / PC5-RRC connection or at least one relay terminal does not establish an end-to-end RRC connection with the network device, at least one of the following is further included: 1, establishing a direct communication interface RRC connection with the relay terminal 2; 2, sending a second message to the relay terminal 2 through the direct communication interface between the relay terminal 1 and the relay terminal 2; 3, sending an end-to-end RRC connection establishment request between the relay terminal 1 and the network device to the network device through a multi-hop relay mode.

[0119] The second message is a trigger message. The second message includes at least one of the following: 1, identification information of the multi-hop relay link; 2, data carried by the SL-RLC0. The second message can be a PC5-RRC or a PC5-S message.

[0120] Specifically, the relay terminal 1 can establish a direct communication interface RRC connection with the relay terminal 2 if the status of the multi-hop relay link meets certain conditions. Specifically, the relay terminal 1 establishes a direct communication interface PC5-RRC connection with the relay terminal 2 if there is no direct communication interface PC5-RRC connection between the relay terminal 1 and the relay terminal 2.

[0121] In addition, the relay terminal 1 can send a second message to the relay terminal 2 through the direct communication interface between the relay terminal 1 and the relay terminal 2 if the status of the multi-hop relay link meets certain conditions. Specifically, the relay terminal 1 sends a second message to the relay terminal 2 through the direct communication interface between the relay terminal 1 and the relay terminal 2 if the following conditions are met. The conditions include at least one of the following: 1, there is a direct communication interface connection between the relay terminal 1 and the relay terminal 2; 2, the relay terminal 2 is in an RRC idle state (IDLE) or in an inactive state (INACTVE) or in an off-network state (OOC); 3, there is no end-to-end RRC connection between the relay terminal 2 and the network device; 4, there is no direct communication interface connection between the relay terminal 2 and the relay terminal 3; 5, at least one relay terminal located between the relay terminal 1 and the network device on the multi-hop relay link is in an RRC idle state (IDLE) or an RRC inactive state (INACTVE) or in an off-network state (OOC).

[0122] In addition, the relay terminal 1 can send an end-to-end RRC connection establishment request between the relay terminal 1 and the network device to the network device through the multi-hop relay mode if the status of the multi-hop relay link meets certain conditions. Specifically, the relay terminal 1 sends an end-to-end RRC connection establishment request between the relay terminal 1 and the network device to the network device through the multi-hop relay mode if the following conditions are met. The conditions include: 1, each relay terminal located between the relay terminal 1 and the network device on the multi-hop relay link has established an end-to-end RRC connection with the network device; 2, there is a direct communication interface PC5-RRC connection between the relay terminal 1 and the relay terminal 2.

[0123] Step 6, if the relay terminal 1 sends a second message to the relay terminal 2 by performing a target operation, the relay terminal 2 performs an operation similar to the target operation described above. For the sake of convenience, the operation similar to the target operation described above is referred to as target operation-2.

[0124] The target operation-2 includes at least one of the following: 1, establishing an end-to-end RRC connection with the network device; 2, establishing a direct communication interface RRC connection with the relay terminal 3; 3, sending a third message to the relay terminal 3 through the direct communication interface between the relay terminal 2 and the relay terminal 3.

[0125] The "establishing an end-to-end RRC connection with the network device" includes establishing an end-to-end RRC connection with the network device through a multi-hop relay mode.

[0126] If the relay terminal 2 needs to establish an end-to-end RRC connection with the network device through a multi-hop relay mode, and if at least one relay terminal between the multi-hop relay and the network device does not have a PC5-S / PC5-RRC connection or at least one relay terminal does not establish an end-to-end RRC connection with the network device, the method further includes at least one of the following: 1, establishing a direct communication interface RRC connection with the relay terminal 3; 2, sending a third message to the relay terminal 3 through the direct communication interface between the relay terminal 2 and the relay terminal 3; 3, sending an end-to-end RRC connection establishment request between the relay terminal 2 and the network device to the network device through a multi-hop relay mode.

[0127] The third message is a trigger message. The third message includes at least one of the following: 1, identification information of the multi-hop relay link; 2, data carried through an SL-RLC0 bearer. The third message can be a PC5-RRC or PC5-S message.

[0128] Specifically, the relay terminal 2 can establish a direct communication interface RRC connection with the relay terminal 3 when the status of the multi-hop relay link meets certain conditions. Specifically, if there is no direct communication interface PC5-RRC connection between the relay terminal 2 and the relay terminal 3, the relay terminal 2 establishes a direct communication interface PC5-RRC connection with the relay terminal 3.

[0129] In addition, the relay terminal 2 can send a third message to the relay terminal 3 through the direct communication interface between the relay terminal 2 and the relay terminal 3 when the status of the multi-hop relay link meets certain conditions. Specifically, if the following conditions are met, the relay terminal 2 sends a third message to the relay terminal 3 through the direct communication interface between the relay terminal 2 and the relay terminal 3. The conditions include at least one of the following: 1, there is a direct communication interface connection between the relay terminal 2 and the relay terminal 3; 2, the relay terminal 3 is in an RRC idle state (IDLE) or in an inactive state (INACTVE) or in an off-network state (OOC); 3, the relay terminal 3 does not have an end-to-end RRC connection with the network device.

[0130] In addition, the relay terminal 2 can send, to the network device, a request for establishing an end-to-end RRC connection between the relay terminal 2 and the network device in a multi-hop relay manner if a condition of the multi-hop relay link meets a certain condition. Specifically, the relay terminal 2 sends, to the network device, the request for establishing the end-to-end RRC connection between the relay terminal 2 and the network device in the multi-hop relay manner if the following condition is met, wherein the first condition includes: 1. the relay terminal 3 has established the end-to-end RRC connection with the network device; and 2. there is a direct communication interface PC5-RRC connection between the relay terminal 2 and the relay terminal 3.

[0131] Step 7, if the relay terminal 2 performs the target operation-2 and sends the third message to the relay terminal 3, if the relay terminal 3 is an in-network terminal and the relay terminal 3 is in an RRC idle state (IDLE) or an RRC inactive state (INACTVE), the relay terminal 3 can establish the end-to-end RRC connection with the network device through the Uu interface between the relay terminal 3 and the network device.

[0132] Embodiment 2

[0133] It is assumed that the remote terminal performs relay discovery and relay selection in the Model B manner, in which case triggering all or part of the relay terminals in the multi-hop relay link to enter the RRC connected state includes the following steps.

[0134] Step 1, the remote terminal performs multi-hop relay link selection in the Model B manner and selects the relay terminal 1.

[0135] Step 2, the remote terminal and the relay terminal 1 establish a direct communication interface connection.

[0136] The direct communication interface connection includes a PC5-S connection and / or a PC5-RRC connection.

[0137] Step 3, the remote terminal sends a first message to the relay terminal 1 through the direct communication interface.

[0138] The first message is a trigger message. The first message includes at least one of the following: 1. identification information of the multi-hop relay link (for example, connection for Multi-hop); 2. identification information of the multi-hop relay link; 3. identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; 4. identification information of all or part of the relay terminals on the multi-hop relay link; and 5. data carried through an SL-RLC0 (direct communication interface designated radio link control channel).

[0139] If the first message includes the identification information of part of the relay terminals on the multi-hop relay link, the identification information of the part of the relay terminals includes the identification information of the relay terminal 2 and the identification information of the relay terminal 3.

[0140] Step 4, the relay terminal 1 performs a target operation.

[0141] The target operation includes at least one of the following: 1, establishing an end-to-end RRC connection with the network device; 2, establishing a direct communication interface RRC connection with the relay terminal 2; 3, sending a second message to the relay terminal 2 through the direct communication interface between the relay terminal 1 and the relay terminal 2.

[0142] The "establishing an end-to-end RRC connection with the network device" includes establishing an end-to-end RRC connection with the network device through a multi-hop relay mode.

[0143] If the relay terminal 1 needs to establish an end-to-end RRC connection with the network device through a multi-hop relay mode, and if at least one relay terminal between the multi-hop relay and the network device does not have a PC5-S / PC5-RRC connection or at least one relay terminal does not establish an end-to-end RRC connection with the network device, the method further includes at least one of the following: 1, establishing a direct communication interface RRC connection with the relay terminal 2; 2, sending a second message to the relay terminal 2 through the direct communication interface between the relay terminal 1 and the relay terminal 2; 3, sending an end-to-end RRC connection establishment request between the relay terminal 1 and the network device to the network device through a multi-hop relay mode.

[0144] The second message is a trigger message. The second message includes at least one of the following: 1, identification information of the multi-hop relay link (for example, connection for Multi-hop); 2, identification information of the multi-hop relay link; 3, identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; 4, identification information of all or part of the relay terminals on the multi-hop relay link; 5, data carried through an SL-RLC0 (direct communication interface designated radio link control channel).

[0145] If the second message includes the identification information of part of the relay terminals on the multi-hop relay link, the identification information of the part of the relay terminals includes the identification information of the relay terminal 2 and the identification information of the relay terminal 3; or the identification information of the part of the relay terminals includes the identification information of the relay terminal 3.

[0146] Specifically, the relay terminal 1 can establish a direct communication interface RRC connection with the relay terminal 2 if a condition is met for the multi-hop relay link, and specifically, the relay terminal 1 establishes a direct communication interface PC5-RRC connection with the relay terminal 2 if there is no direct communication interface PC5-RRC connection between the relay terminal 1 and the relay terminal 2.

[0147] In addition, the relay terminal 1 can send a second message to the relay terminal 2 through the direct communication interface between the relay terminal 1 and the relay terminal 2 if a condition is met for the multi-hop relay link, and specifically, the relay terminal 1 sends the second message to the relay terminal 2 through the direct communication interface between the relay terminal 1 and the relay terminal 2 if the following conditions are met. The conditions include at least one of the following: 1, there is a direct communication interface connection between the relay terminal 1 and the relay terminal 2; 2, the relay terminal 2 is in an RRC idle state (IDLE) or in an inactive state (INACTVE) or in an off-network state (OOC); 3, there is no end-to-end RRC connection between the relay terminal 2 and the network device; 4, there is no direct communication interface connection between the relay terminal 2 and the relay terminal 3; 5, at least one relay terminal located between the relay terminal 1 and the network device on the multi-hop relay link is in an RRC idle state (IDLE) or an RRC inactive state (INACTVE) or in an off-network state (OOC).

[0148] In addition, the relay terminal 1 can send an end-to-end RRC connection establishment request between the relay terminal 1 and the network device to the network device through the multi-hop relay mode if a condition is met for the multi-hop relay link, and specifically, the relay terminal 1 sends the end-to-end RRC connection establishment request between the relay terminal 1 and the network device to the network device through the multi-hop relay mode if the following conditions are met. The conditions include: 1, each relay terminal located between the relay terminal 1 and the network device on the multi-hop relay link has established an end-to-end RRC connection with the network device; 2, there is a direct communication interface PC5-RRC connection between the relay terminal 1 and the relay terminal 2.

[0149] Step 5, if the relay terminal 1 sends the second message to the relay terminal 2 by performing the target operation, the relay terminal 2 performs an operation similar to the target operation described above. For the sake of convenience, the operation similar to the target operation described above is referred to as target operation-2.

[0150] The target operation-2 includes at least one of the following: 1, establishing an end-to-end RRC connection with the network device; 2, establishing a direct communication interface RRC connection with the relay terminal 3; 3, sending a third message to the relay terminal 3 through the direct communication interface between the relay terminal 2 and the relay terminal 3.

[0151] The "establishing an end-to-end RRC connection with the network device" includes: establishing the end-to-end RRC connection with the network device through the multi-hop relay mode.

[0152] If the relay terminal 2 needs to establish the end-to-end RRC connection with the network device through the multi-hop relay mode, and if at least one relay terminal between the multi-hop relay and the network device does not have the PC5-S / PC5-RRC connection or at least one relay terminal does not establish the end-to-end RRC connection with the network device, the method further includes at least one of the following: 1. establishing a direct communication interface RRC connection with the relay terminal 3; 2. sending a third message to the relay terminal 3 through the direct communication interface between the relay terminal 2 and the relay terminal 3; and 3. sending a request for establishing the end-to-end RRC connection between the relay terminal 2 and the network device to the network device through the multi-hop relay mode.

[0153] The third message is a trigger message. The third message includes at least one of the following: 1. identification information of the multi-hop relay link (for example, connection for Multi-hop); 2. identification information of the multi-hop relay link; 3. identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; 4. identification information of all or part of the relay terminals on the multi-hop relay link; and 5. data carried through the SL-RLC0 (direct communication interface designated radio link control channel).

[0154] If the third message includes the identification information of the part of the relay terminals on the multi-hop relay link, the identification information of the part of the relay terminals includes the identification information of the relay terminal 3.

[0155] Specifically, the relay terminal 2 can establish the direct communication interface RRC connection with the relay terminal 3 when the condition of the multi-hop relay link meets a certain condition. Specifically, if there is no direct communication interface PC5-RRC connection between the relay terminal 2 and the relay terminal 3, the relay terminal 2 establishes the direct communication interface PC5-RRC connection with the relay terminal 3.

[0156] In addition, the relay terminal 2 can send the third message to the relay terminal 3 through the direct communication interface between the relay terminal 2 and the relay terminal 3 when the condition of the multi-hop relay link meets a certain condition. Specifically, the relay terminal 2 sends the third message to the relay terminal 3 through the direct communication interface between the relay terminal 2 and the relay terminal 3 if the following conditions are met. The conditions include at least one of the following: 1. there is a direct communication interface connection between the relay terminal 2 and the relay terminal 3; 2. the relay terminal 3 is in an RRC idle state (IDLE) or in an inactive state (INACTVE) or in an off-network state (OOC); and 3. there is no end-to-end RRC connection between the relay terminal 3 and the network device.

[0157] In addition, the relay terminal 2 can send the end-to-end RRC connection establishment request between the relay terminal 2 and the network device to the network device through the multi-hop relay mode in a case where the condition of the multi-hop relay link meets a certain condition. Specifically, the relay terminal 2 sends the end-to-end RRC connection establishment request between the relay terminal 2 and the network device to the network device through the multi-hop relay mode if the following condition is met, wherein the first condition includes: 1. the relay terminal 3 has established the end-to-end RRC connection with the network device; 2. there is a direct communication interface PC5-RRC connection between the relay terminal 2 and the relay terminal 3.

[0158] Step 6, if the relay terminal 2 performs the target operation-2 and sends the third message to the relay terminal 3, if the relay terminal 3 is an in-network terminal, and the relay terminal 3 is in the RRC idle state (IDLE) or the RRC inactive state (INACTVE), then the relay terminal 3 can establish the end-to-end RRC connection with the network device through the Uu interface between the relay terminal 3 and the network device.

[0159] It should be understood that although each step in the flowchart of FIG. 5 is shown in sequence according to the direction of the arrow, these steps are not necessarily executed in sequence according to the direction of the arrow. Unless otherwise explicitly stated herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, at least part of the steps in FIG. 5 can include multiple steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of these steps or stages is not necessarily sequential, but can be alternately or alternately executed with at least part of other steps or steps or stages in other steps.

[0160] The technical solutions provided by the embodiments of the present disclosure can be applied to various systems. For example, the applicable systems can be a long term evolution (LTE) system, an LTE frequency division duplex (FDD) system, an LTE time division duplex (TDD) system, a long term evolution advanced (LTE-A) system, a universal mobile system (UMTS), a worldwide interoperability for microwave access (WiMAX) system, a 5G new radio (NR) system and an evolved communication system thereof, a 6G (sixth generation mobile communication technology) system, and the like. The various systems can include terminal devices and network devices. The system can also include a core network part, such as an evolved packet system (EPC), a 5G core network (5GC), and the like.

[0161] Based on the same technical concept, the embodiments of the present disclosure also provide an RRC connection establishment apparatus.

[0162] In one embodiment, as shown in FIG. 6, an RRC connection establishment apparatus 600 is provided for a first relay terminal, which is any relay terminal on a multi-hop relay link, comprising a receiving unit 601 and an executing unit 602.

[0163] The receiving unit 601 is configured to receive a first message from a previous hop node in a first transmission direction.

[0164] The executing unit 602 is configured to perform a target operation.

[0165] The first relay terminal is any relay terminal on the multi-hop relay link, the first transmission direction is a transmission direction from a remote terminal to a network device or an uplink transmission direction, and a previous hop node in the first transmission direction is the remote terminal or a second relay terminal. The first message includes at least one of the following: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; data of a wireless link control channel SL-RLC0 bearer specified through a direct communication interface; and target operations include at least one of the following: establishing an end-to-end RRC connection with the network device; establishing a direct communication interface RRC connection with a third relay terminal, the third relay terminal being a next hop relay terminal in the first transmission direction; and sending the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal.

[0166] In one of the embodiments, the first message includes identification information of part of the relay terminals on the multi-hop relay link, including: the first message includes identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link; or the first message includes identification information of the first relay terminal and identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link.

[0167] In one of the embodiments, in the case where the execution unit 602 is configured to establish an end-to-end RRC connection with the network device, the execution unit 602 is configured to perform any one of the following: establishing an end-to-end RRC connection with the network device through a Uu interface between the first relay terminal and the network device; and establishing an end-to-end RRC connection with the network device through a multi-hop relay mode.

[0168] In one of the embodiments, the execution unit 602 is configured to: if the first relay terminal is an in-network terminal and the first relay terminal is in an RRC idle state or an RRC inactive state, establish an end-to-end RRC connection with the network device through a Uu interface between the first relay terminal and the network device.

[0169] In one of the embodiments, the execution unit 602 is configured to perform at least one of the following: establishing a direct communication interface RRC connection with a third relay terminal; sending the second message to the third relay terminal through a direct communication interface between the first relay terminal and the third relay terminal; and sending an end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through a multi-hop relay mode.

[0170] In one of the embodiments, the second message comprises at least one of the following information: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of each relay terminal and identification information of the remote terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; and data carried by the SL-RLC0.

[0171] In one of the embodiments, the second message comprises identification information of part of the relay terminals on the multi-hop relay link, including: the second message comprises identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link; or the second message comprises identification information of the third relay terminal and identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link.

[0172] In one of the embodiments, when the execution unit 602 is configured to send, to the network device, the end-to-end RRC connection establishment request between the first relay terminal and the network device in the multi-hop relay mode, the execution unit 602 is configured to: if a first condition is met, send, to the network device, the end-to-end RRC connection establishment request between the first relay terminal and the network device in the multi-hop relay mode; and the first condition comprises: each relay terminal between the first relay terminal and the network device on the multi-hop relay link has established an end-to-end RRC connection with the network device; and there is a direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal.

[0173] In one of the embodiments, when the execution unit 602 is configured to establish a direct communication interface RRC connection with the third relay terminal, the execution unit 602 is configured to: if there is no direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal, establish a direct communication interface PC5-RRC connection with the third relay terminal.

[0174] In one of the embodiments, when the execution unit 602 is configured to send, to the third relay terminal, the second message through the direct communication interface between the first relay terminal and the third relay terminal, the execution unit 602 is configured to: if a second condition is met, send, to the third relay terminal, the second message through the direct communication interface between the first relay terminal and the third relay terminal; and the second condition comprises at least one of the following: there is a direct communication interface connection between the first relay terminal and the third relay terminal; the third relay terminal is in an RRC idle state or in an inactive state or in a disconnection state; there is no end-to-end RRC connection between the third relay terminal and the network device; there is no direct communication interface connection between the third relay terminal and the next-hop relay terminal of the third relay terminal in the first transmission direction; and at least one relay terminal between the first relay terminal and the network device on the multi-hop relay link is in an RRC idle state or an RRC inactive state or in a disconnection state.

[0175] In one of the embodiments, the receiving unit 601 is further configured to receive a third message, the third message carrying an end-to-end RRC connection state between at least one relay terminal and the network device over the multi-hop relay link and / or a direct communication interface PC5-RRC connection state between the relay terminals.

[0176] In one of the embodiments, the third message comprises at least one of the following: a relay discovery related message; a PC5-RRC message.

[0177] It is to be noted that the above RRC connection establishment apparatus provided by the embodiments of the present disclosure can implement all the method steps achieved by the above RRC connection establishment method embodiments for the first relay terminal, and achieve the same technical effects. Therefore, the parts and beneficial effects of the embodiments that are the same as the method embodiments will not be described in detail herein.

[0178] The above modules in the RRC connection establishment apparatus can be all or partially implemented by software, hardware and combination thereof. The above modules can be embedded in or independent of the processor in the first relay terminal in hardware form, or stored in the memory in the first relay terminal in software form, so as to be called and executed by the processor to perform the operations corresponding to the above modules.

[0179] Based on the same technical concept, the embodiments of the present disclosure further provide a first relay terminal. The first relay terminal can implement the functions of the first relay terminal in the foregoing embodiments.

[0180] FIG. 7 is a structural schematic diagram of a first relay terminal provided by the embodiments of the present disclosure. The first relay terminal can include a processor 700, a transceiver 710 and a memory 720. The transceiver 710 is configured to receive and send data under the control of the processor 700.

[0181] In FIG. 7, the bus architecture can include any number of interconnected buses and bridges, which are specifically linked together by various circuits of one or more processors represented by the processor 700 and the memory represented by the memory 720. The bus architecture can also link various other circuits such as peripheral devices, voltage stabilizers and power management circuits, which are well known in the art, and thus, will not be further described herein. The bus interface provides an interface.

[0182] The transceiver 710 can be a plurality of elements, i.e., including a transmitter and a receiver, providing a unit for communicating with various other devices over transmission media, including wireless channels, wired channels, optical cables, etc. transmission media. For different user equipment, the user interface can also be an interface that can be externally connected to the required equipment, including but not limited to a keypad, a display, a speaker, a microphone, a joystick, etc.

[0183] The processor 700 is responsible for managing the bus architecture and general processing, and the memory 720 can store data used by the processor 700 when performing operations.

[0184] In some embodiments, the processor 700 can be a CPU (Central Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a CPLD (Complex Programmable Logic Device), and the processor 700 can also adopt a multi-core architecture. The processor 700 and the memory 720 can also be physically arranged separately.

[0185] The processor 700 calls the program stored in the memory to perform the following steps according to the obtained executable instructions:

[0186] The control transceiver 710 receives a first message from a previous hop node in a first transmission direction; performs a target operation; wherein the first relay terminal is any relay terminal on a multi-hop relay link, the first transmission direction is a transmission direction from a remote terminal to a network device or an uplink transmission direction, and the previous hop node in the first transmission direction is a remote terminal or a second relay terminal; The first message includes at least one of the following: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; data specified by the direct communication interface SL-RLC0 bearer of the wireless link control channel; The target operation includes at least one of the following: establishing an end-to-end RRC connection with the network device; establishing a direct communication interface RRC connection with a third relay terminal, the third relay terminal being a next hop relay terminal in the first transmission direction; sending a second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal.

[0187] In one of the embodiments, the first message includes the identification information of part of the relay terminals on the multi-hop relay link, including: the first message includes the identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link; or, the first message includes the identification information of the first relay terminal and the identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link.

[0188] In one of the embodiments, the establishing the end-to-end RRC connection with the network device includes any of the following: the control transceiver 710 establishes the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device; the control transceiver 710 establishes the end-to-end RRC connection with the network device through the multi-hop relay mode.

[0189] In one of the embodiments, the control transceiver 710 establishes the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device, including: if the first relay terminal is an in-network terminal, and the first relay terminal is in the RRC idle state or the RRC inactive state, the control transceiver 710 establishes the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device.

[0190] In one of the embodiments, the control transceiver 710 establishes the end-to-end RRC connection with the network device through the multi-hop relay mode, including at least one of the following: the control transceiver 710 establishes a direct communication interface RRC connection with the third relay terminal; the control transceiver 710 sends a second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal; the control transceiver 710 sends an end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode.

[0191] In one of the embodiments, the second message includes at least one of the following information: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of each relay terminal and the remote terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; data carried by the SL-RLC0.

[0192] In one of the embodiments, the second message includes the identification information of part of the relay terminals on the multi-hop relay link, including: the second message includes the identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link; or, the second message includes the identification information of the third relay terminal and the identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link.

[0193] In one of the embodiments, the control transceiver 710 sends, to the network device, the end-to-end RRC connection setup request between the first relay terminal and the network device in a multi-hop relay manner, including: if a first condition is met, the control transceiver 710 sends, to the network device, the end-to-end RRC connection setup request between the first relay terminal and the network device in a multi-hop relay manner; wherein the first condition includes: each relay terminal located between the first relay terminal and the network device on the multi-hop relay link has established an end-to-end RRC connection with the network device; and there is a direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal.

[0194] In one of the embodiments, the control transceiver 710 establishes a direct communication interface RRC connection with the third relay terminal, including: if there is no direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal, the control transceiver 710 establishes a direct communication interface PC5-RRC connection with the third relay terminal.

[0195] In one of the embodiments, the control transceiver 710 sends, to the third relay terminal, the second message through the direct communication interface between the first relay terminal and the third relay terminal, including: if a second condition is met, the control transceiver 710 sends, to the third relay terminal, the second message through the direct communication interface between the first relay terminal and the third relay terminal; wherein the second condition includes at least one of the following: there is a direct communication interface connection between the first relay terminal and the third relay terminal; the third relay terminal is in an RRC idle state or in an inactive state or in an off-network state; there is no end-to-end RRC connection between the third relay terminal and the network device; there is no direct communication interface connection between the third relay terminal and the next-hop relay terminal of the third relay terminal in the first transmission direction; at least one relay terminal located between the first relay terminal and the network device on the multi-hop relay link is in an RRC idle state or an RRC inactive state or in an off-network state.

[0196] In one of the embodiments, the processor is further configured to control the control transceiver 710 to receive a third message, the third message carrying an end-to-end RRC connection state between at least one relay terminal on the multi-hop relay link and the network device and / or a direct communication interface PC5-RRC connection state between relay terminals.

[0197] In one of the embodiments, the third message includes at least one of the following: a relay discovery related message; a PC5-RRC message.

[0198] In one embodiment, a computer readable storage medium is provided, which can be any available medium or data storage device that can be accessed by a processor including, but not limited to, a magnetic storage device (e.g., floppy diskette, hard disk, tape, MO, etc.), an optical storage device (e.g., CD, DVD, BD, HVD, etc.), and a semiconductor memory (e.g., ROM, EPROM, EEPROM, NAND FLASH, SSD, etc.), etc.

[0199] In one embodiment, a computer readable storage medium is provided, which can be any available medium or data storage device that can be accessed by a processor including, but not limited to, a magnetic storage device (e.g., floppy diskette, hard disk, tape, MO, etc.), an optical storage device (e.g., CD, DVD, BD, HVD, etc.), and a semiconductor memory (e.g., ROM, EPROM, EEPROM, NAND FLASH, SSD, etc.), etc.

[0200] receiving a first message from a previous hop node in a first transmission direction; performing a target operation;

[0201] Wherein, the first transmission direction is a transmission direction from a remote terminal to a network device or an uplink transmission direction, and the previous hop node in the first transmission direction is the remote terminal or a second relay terminal; the first message includes at least one of the following: identification information of a multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; data of a SL-RLC0 bearer specified through a direct communication interface; the target operation includes at least one of the following: establishing an end-to-end RRC connection with the network device; establishing an RRC connection of a direct communication interface with a third relay terminal, which is a next hop relay terminal in the first transmission direction; sending a second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal.

[0202] In one embodiment, the first message includes identification information of part of the relay terminals on the multi-hop relay link, including: the first message includes identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link; or, the first message includes identification information of the first relay terminal and identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link.

[0203] In one embodiment, establishing an end-to-end RRC connection with the network device includes any one of the following: establishing an end-to-end RRC connection with the network device through a Uu interface between the first relay terminal and the network device; establishing an end-to-end RRC connection with the network device through a multi-hop relay mode.

[0204] In one of the embodiments, the establishing the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device comprises: if the first relay terminal is an in-network terminal, and the first relay terminal is in an RRC idle state or an RRC inactive state, establishing the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device.

[0205] In one of the embodiments, the establishing the end-to-end RRC connection with the network device through the multi-hop relay mode comprises at least one of the following: establishing a direct communication interface RRC connection with the third relay terminal; sending a second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal; and sending an end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode.

[0206] In one of the embodiments, the second message comprises at least one of the following information: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of each relay terminal and identification information of the remote terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; and data carried by the SL-RLC0.

[0207] In one of the embodiments, the second message comprises identification information of part of the relay terminals on the multi-hop relay link, which comprises: the second message comprises identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link; or the second message comprises identification information of the third relay terminal and identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link.

[0208] In one of the embodiments, the sending the end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode comprises: if a first condition is met, sending the end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode; wherein the first condition comprises: each relay terminal between the first relay terminal and the network device on the multi-hop relay link has established an end-to-end RRC connection with the network device; and there is a direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal.

[0209] In one of the embodiments, the establishing the direct communication interface RRC connection with the third relay terminal comprises: if there is no direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal, establishing the direct communication interface PC5-RRC connection with the third relay terminal.

[0210] In one of the embodiments, the sending the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal comprises: if the second condition is met, sending the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal; and the second condition comprises at least one of the following: the first relay terminal and the third relay terminal have a direct communication interface connection; the third relay terminal is in an RRC idle state or in an inactive state or in a disconnection state; the third relay terminal and the network device do not have an end-to-end RRC connection; the third relay terminal and a next-hop relay terminal of the third relay terminal in the first transmission direction do not have a direct communication interface connection; at least one relay terminal between the first relay terminal and the network device on the multi-hop relay link is in an RRC idle state or an RRC inactive state or in a disconnection state.

[0211] In one of the embodiments, the computer program, when executed by the processor, further implements the following steps: receiving a third message, the third message carrying an end-to-end RRC connection state between at least one relay terminal on the multi-hop relay link and the network device and / or a direct communication interface PC5-RRC connection state between relay terminals.

[0212] In one of the embodiments, the third message comprises at least one of the following: a relay discovery related message; a PC5-RRC message.

[0213] FIG. 8 is a schematic structural diagram of a chip according to an embodiment of the present disclosure. The chip 800 shown in FIG. 8 comprises a processor 810, which can invoke and run a computer program from a memory to implement the method in the embodiments of the present disclosure.

[0214] Optionally, as shown in FIG. 8, the chip 800 can further comprise a memory 820. The processor 810 can invoke and run a computer program from the memory 820 to implement the method in the embodiments of the present disclosure.

[0215] The memory 820 can be a separate device independent of the processor 810, or can be integrated in the processor 810.

[0216] Optionally, the chip 800 can further comprise an input interface 830. The processor 810 can control the input interface 830 to communicate with other devices or chips, and specifically, can obtain information or data sent by other devices or chips.

[0217] Optionally, the chip 800 can further comprise an output interface 840. The processor 810 can control the output interface 840 to communicate with other devices or chips, and specifically, can output information or data to other devices or chips.

[0218] Optionally, the chip 800 can be applied to a network element device in the embodiments of the present disclosure, and the chip 800 can implement corresponding processes implemented in various methods of the embodiments of the present disclosure. For brevity, details are not repeated here.

[0219] It should be understood that the chip 800 mentioned in the embodiments of the present disclosure can also be referred to as a system chip, a system-on-chip, a chip system or a system-on-chip, etc.

[0220] In one embodiment, a computer program product is provided, which can be used in a first relay terminal, the first relay terminal being any relay terminal in a multi-hop relay link, and the computer program product comprises a computer program which, when executed by a processor, implements the following steps:

[0221] receiving a first message from a previous hop node in a first transmission direction; performing a target operation;

[0222] The first transmission direction is a transmission direction from a remote terminal to a network device or an uplink transmission direction, and the previous hop node in the first transmission direction is the remote terminal or a second relay terminal. The first message comprises at least one of the following: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; data of a SL-RLC0 bearer specified by a direct communication interface; the target operation comprises at least one of the following: establishing an end-to-end RRC connection with the network device; establishing an RRC connection of a direct communication interface with a third relay terminal, the third relay terminal being a next hop relay terminal in the first transmission direction; and sending a second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal.

[0223] In one embodiment, the first message comprises identification information of part of the relay terminals on the multi-hop relay link, which comprises: the first message comprises identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link; or the first message comprises identification information of the first relay terminal and identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link.

[0224] In one embodiment, establishing an end-to-end RRC connection with the network device comprises any one of the following: establishing an end-to-end RRC connection with the network device through a Uu interface between the first relay terminal and the network device; and establishing an end-to-end RRC connection with the network device through a multi-hop relay mode.

[0225] In one of the embodiments, the establishing the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device comprises: if the first relay terminal is an in-network terminal, and the first relay terminal is in an RRC idle state or an RRC inactive state, establishing the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device.

[0226] In one of the embodiments, the establishing the end-to-end RRC connection with the network device through the multi-hop relay mode comprises at least one of the following: establishing a direct communication interface RRC connection with the third relay terminal; sending a second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal; and sending an end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode.

[0227] In one of the embodiments, the second message comprises at least one of the following information: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of each relay terminal and identification information of the remote terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; and data carried by the SL-RLC0.

[0228] In one of the embodiments, the second message comprises identification information of part of the relay terminals on the multi-hop relay link, which comprises: the second message comprises identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link; or the second message comprises identification information of the third relay terminal and identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link.

[0229] In one of the embodiments, the sending the end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode comprises: if a first condition is met, sending the end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode; wherein the first condition comprises: each relay terminal between the first relay terminal and the network device on the multi-hop relay link has established an end-to-end RRC connection with the network device; and there is a direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal.

[0230] In one of the embodiments, the establishing the direct communication interface RRC connection with the third relay terminal comprises: if there is no direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal, establishing the direct communication interface PC5-RRC connection with the third relay terminal.

[0231] In one of the embodiments, the sending the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal comprises: if the second condition is satisfied, sending the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal; and the second condition comprises at least one of the following: the first relay terminal and the third relay terminal have a direct communication interface connection; the third relay terminal is in an RRC idle state or in an inactive state or in a disconnection state; the third relay terminal and the network device do not have an end-to-end RRC connection; the third relay terminal and a next-hop relay terminal of the third relay terminal in the first transmission direction do not have a direct communication interface connection; at least one relay terminal between the first relay terminal and the network device on the multi-hop relay link is in an RRC idle state or in an RRC inactive state or in a disconnection state.

[0232] In one of the embodiments, the computer program, when executed by the processor, further implements the following steps: receiving a third message, the third message carrying an end-to-end RRC connection state between at least one relay terminal on the multi-hop relay link and the network device and / or a direct communication interface PC5-RRC connection state between relay terminals.

[0233] In one of the embodiments, the third message comprises at least one of the following: a relay discovery related message; a PC5-RRC message.

[0234] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be completed by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer readable storage medium, and when executed, can include the processes of the above-mentioned embodiments. Any reference to memory, storage, database or other medium used in the embodiments of the present disclosure can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0235] Any combination of the technical features in the above embodiments can be made, and for the sake of brevity, not all possible combinations are described above, however, as long as the combination of the technical features does not exist in contradiction, it shall be considered within the scope of the present disclosure.

[0236] The above-described embodiments only express several implementation manners of the present disclosure, and the description is relatively specific and detailed, but it shall not be understood as a limitation on the patent scope of the present disclosure. It shall be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present disclosure, and these shall be within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure patent shall be subject to the appended claims.

Claims

1. A radio resource control (RRC) connection setup method, wherein, The method for the first relay terminal comprises: receiving a first message from a previous hop node in a first transmission direction; performing a target operation; wherein the first relay terminal is any relay terminal on a multi-hop relay link, the first transmission direction is a transmission direction from a remote terminal to a network device or an uplink transmission direction, and the previous hop node in the first transmission direction is the remote terminal or a second relay terminal; the first message comprises at least one of: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; designating data of a sidelink radio link control (SL-RLC) 0 bearer through a direct communication interface; the target operation comprises at least one of: establishing an end-to-end radio resource control (RRC) connection with the network device; establishing a direct communication interface RRC connection with a third relay terminal, which is a next hop relay terminal in the first transmission direction; and sending a second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal.

2. The method of claim 1, wherein, the first message comprises identification information of part of the relay terminals on the multi-hop relay link, including: the first message comprises identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link; or the first message comprises identification information of the first relay terminal and identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link.

3. The method of claim 1, wherein, the end-to-end RRC connection with the network device comprises any of: establishing the end-to-end RRC connection with the network device through a Uu interface between the first relay terminal and the network device; and establishing the end-to-end RRC connection with the network device through a multi-hop relay mode.

4. The method of claim 3, wherein, the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device comprises: if the first relay terminal is an in-network terminal and the first relay terminal is in an RRC idle state or an RRC inactive state, establishing the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device.

5. The method of claim 3, wherein, the end-to-end RRC connection with the network device through the multi-hop relay mode comprises at least one of: establishing the direct communication interface RRC connection with the third relay terminal; sending the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal; and sending an end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device through the multi-hop relay mode.

6. The method of claim 1 or 5, wherein, the second message comprises at least one of: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; Identity information of all or part of relay terminals on the multi-hop relay link; Data carried by the SL-RLC0 bearer.

7. The method of claim 6, wherein, The second message includes identity information of part of relay terminals on the multi-hop relay link, including: The second message includes identity information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link; or, The second message includes identity information of the third relay terminal and identity information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link.

8. The method of claim 5, wherein, The method further includes: If a first condition is met, sending, by the first relay terminal, an end-to-end RRC connection establishment request between the first relay terminal and the network device to the network device in a multi-hop relay manner; The first condition includes: Each relay terminal located between the first relay terminal and the network device on the multi-hop relay link has established an end-to-end RRC connection with the network device; There is a direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal.

9. The method of claim 1 or 5, wherein, The first relay terminal and the third relay terminal establish a direct communication interface RRC connection, including: If there is no direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal, the first relay terminal and the third relay terminal establish a direct communication interface PC5-RRC connection.

10. The method of claim 1 or 5, wherein, The method further includes: If a second condition is met, sending, by the first relay terminal, the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal; The second condition includes at least one of the following: There is a direct communication interface connection between the first relay terminal and the third relay terminal; The third relay terminal is in an RRC idle state or in an inactive state or in an off-network state; There is no end-to-end RRC connection between the third relay terminal and the network device; There is no direct communication interface connection between the third relay terminal and the next-hop relay terminal of the third relay terminal in the first transmission direction; At least one relay terminal located between the first relay terminal and the network device on the multi-hop relay link is in an RRC idle state or an RRC inactive state or in an off-network state.

11. The method of claim 8 or 10, wherein, The method further includes: Receiving a third message, the third message carrying an end-to-end RRC connection state between at least one relay terminal on the multi-hop relay link and a network device and / or a direct communication interface PC5-RRC connection state between relay terminals.

12. The method of claim 11, wherein, The third message includes at least one of the following: Relay discovery related messages; PC5-RRC messages.

13. An RRC connection setup apparatus, wherein, For a first relay terminal, the first relay terminal being any relay terminal on a multi-hop relay link, the apparatus includes: The receiving unit is configured to receive a first message from a previous hop node in a first transmission direction; The performing unit is configured to perform a target operation; The first transmission direction is a transmission direction from a remote terminal to a network device or an uplink transmission direction, and the previous hop node in the first transmission direction is the remote terminal or a second relay terminal. The first message includes at least one of the following: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; data of a wireless link control channel (SL-RLC0) bearer specified through a direct communication interface; The target operation includes at least one of the following: establishing an end-to-end RRC connection with the network device; establishing a direct communication interface RRC connection with a third relay terminal, which is a next hop relay terminal in the first transmission direction; and sending a second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal.

14. A relay terminal, wherein, The relay terminal is a first relay terminal, which is any relay terminal on a multi-hop relay link, and includes a memory, a transceiver, and a processor: The memory is configured to store a computer program. The transceiver is configured to transceive data under control of the processor. The processor is configured to read the computer program in the memory and perform the following operations: controlling the transceiver to receive a first message from a previous hop node in a first transmission direction; performing a target operation; The first transmission direction is a transmission direction from a remote terminal to a network device or an uplink transmission direction, and the previous hop node in the first transmission direction is the remote terminal or a second relay terminal. The first message includes at least one of the following: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; data of a wireless link control channel (SL-RLC0) bearer specified through a direct communication interface; The target operation includes at least one of the following: establishing an end-to-end RRC connection with the network device; establishing a direct communication interface RRC connection with a third relay terminal, which is a next hop relay terminal in the first transmission direction; and 15. The relay terminal of claim 14, wherein, sending a second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal. The first message includes identification information of part of the relay terminals on the multi-hop relay link, including: The first message includes identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link; or The first message includes identification information of the first relay terminal and identification information of each relay terminal between the first relay terminal and the network device on the multi-hop relay link.

16. The relay terminal of claim 14, wherein, The establishing the end-to-end RRC connection with the network device comprises any one of the following: controlling the transceiver to establish the end-to-end RRC connection with the network device through a Uu interface between the first relay terminal and the network device; controlling the transceiver to establish the end-to-end RRC connection with the network device through a multi-hop relay mode.

17. The relay terminal of claim 16, wherein, The controlling the transceiver to establish the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device comprises: if the first relay terminal is an in-network terminal, and the first relay terminal is in an RRC idle state or an RRC inactive state, controlling the transceiver to establish the end-to-end RRC connection with the network device through the Uu interface between the first relay terminal and the network device.

18. The relay terminal of claim 16, wherein, The controlling the transceiver to establish the end-to-end RRC connection with the network device through the multi-hop relay mode comprises at least one of the following: controlling the transceiver to establish a direct communication interface RRC connection with the third relay terminal; controlling the transceiver to send the second message to the third relay terminal through a direct communication interface between the first relay terminal and the third relay terminal; controlling the transceiver to send, to the network device, a request for establishing an end-to-end RRC connection between the first relay terminal and the network device through a multi-hop relay mode.

19. The relay terminal according to claim 14 or 18, wherein The second message comprises at least one of the following information: identification information of the multi-hop relay link; identification information of the multi-hop relay link; identification information of the remote terminal and identification information of each relay terminal on the multi-hop relay link; identification information of all or part of the relay terminals on the multi-hop relay link; data carried by an SL-RLC0 bearer.

20. The relay terminal of claim 19, wherein, The second message comprises identification information of part of the relay terminals on the multi-hop relay link, comprising: The second message comprises identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link; or The second message comprises identification information of the third relay terminal and identification information of each relay terminal between the third relay terminal and the network device on the multi-hop relay link.

21. The relay terminal of claim 18, wherein, The controlling the transceiver to send, to the network device, a request for establishing an end-to-end RRC connection between the first relay terminal and the network device through a multi-hop relay mode comprises: if a first condition is met, controlling the transceiver to send, to the network device, a request for establishing an end-to-end RRC connection between the first relay terminal and the network device through a multi-hop relay mode; wherein the first condition comprises: each relay terminal between the first relay terminal and the network device on the multi-hop relay link has established an end-to-end RRC connection with the network device; there is a direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal.

22. The relay terminal of claim 18, wherein, The controlling the transceiver to establish a direct communication interface RRC connection with the third relay terminal comprises: If there is no direct communication interface PC5-RRC connection between the first relay terminal and the third relay terminal, the transceiver is controlled to establish a direct communication interface PC5-RRC connection with the third relay terminal.

23. The relay terminal of claim 18, wherein, The control of the transceiver to send the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal includes: If a second condition is met, the transceiver is controlled to send the second message to the third relay terminal through the direct communication interface between the first relay terminal and the third relay terminal. The second condition includes at least one of the following: There is a direct communication interface connection between the first relay terminal and the third relay terminal; The third relay terminal is in an RRC idle state or in an inactive state or in an off-network state; There is no end-to-end RRC connection between the third relay terminal and the network device; There is no direct communication interface connection between the third relay terminal and the next-hop relay terminal of the third relay terminal in the first transmission direction; At least one relay terminal between the first relay terminal and the network device on the multi-hop relay link is in an RRC idle state or an RRC inactive state or in an off-network state.

24. The relay terminal according to claim 21 or 23, wherein The processor is further configured to perform the following operations: The transceiver is controlled to receive a third message, and the third message carries an end-to-end RRC connection state between at least one relay terminal on the multi-hop relay link and a network device and / or a direct communication interface PC5-RRC connection state between relay terminals.

25. The relay terminal of claim 24, wherein, The third message includes at least one of the following: A relay discovery related message; A PC5-RRC message.

26. A processor-readable storage medium, wherein, The processor readable storage medium stores a program for causing the processor to perform the method of any one of claims 1 to 12.

Images