Data transmission method and device in multi-hop relay scene

Abstract

The invention provides a data transmission method and device in a multi-hop relay scene, and the method comprises the steps: receiving data from a last-hop node; any one of the following operations is executed: replacement between a first local identifier of a remote terminal and a second local identifier of the remote terminal is executed on a direct communication interface link relay adaptation protocol (SRAP) layer; a first local identifier of the remote terminal and a second local identifier of the remote terminal are simultaneously carried in an SRAP protocol data unit PDU header; the second local identifier of the remote terminal is used in the SRAP PDU head; and using the first local identifier of the remote terminal in the SRAP PDU header. According to the data transmission method and device in the multi-hop relay scene provided by the invention, the data can be correctly routed to the target node.

Description

Technical Field

[0001] This application relates to the field of communication technologies, and in particular, to a data transmission method and apparatus in a multi-hop relay scenario. Background Art

[0002] In a multi-hop UE-to-Network (U2N) relay scenario, the data of a remote terminal needs to be forwarded to a network device through N (N is greater than or equal to 1) UE-to-UE (U2U) relays and one U2N relay. In this case, since the local identifier assigned to the U2U relay by the U2U relay and the local identifier assigned to the U2N relay by a network device (such as a base station) are completely two independent identifiers, if the U2N relay processes according to the existing protocol, after the U2N relay receives data from the previous-hop U2U relay, the local identifier assigned by the U2U relay and the local identifier assigned by the network device cannot be associated at the Sidelink Relay Adaptation Protocol (SRAP) layer of the direct communication interface link relay. Therefore, it cannot be ensured that the data can be correctly routed to the target node, resulting in communication interruption. Summary of the Invention

[0003] This application provides a data transmission method and apparatus in a multi-hop relay scenario, which solves the problem that in the multi-hop U2N relay scenario, the prior art cannot ensure that the data can be correctly routed to the target node.

[0004] In a first aspect, this application provides a data transmission method in a multi-hop relay scenario, which is applied to a UE-to-Network (U2N) relay. The method includes:

[0005] After receiving data from the previous-hop node, perform any one of the following operations:

[0006] Perform replacement between a first local identifier of a remote terminal and a second local identifier of the remote terminal at the Sidelink Relay Adaptation Protocol (SRAP) layer of the direct communication interface link relay;

[0007] Simultaneously carry the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit (PDU) header;

[0008] Use the second local identifier of the remote terminal in the SRAP PDU header;

[0009] Use the first local identifier of the remote terminal in the SRAP PDU header;

[0010] Wherein, in the uplink transmission direction, the previous hop node is a terminal-to-terminal relay U2U relay; in the downlink transmission direction, the previous hop node is a network device; the first local identifier of the remote terminal is a local identifier assigned to the remote terminal by a first U2U relay between the remote terminal and the U2N relay, and the first U2U relay is any U2U relay or a specified U2U relay between the remote terminal and the U2N relay; the second local identifier of the remote terminal is a local identifier assigned to the remote terminal by the network device.

[0011] In the embodiments of the present application, the U2N relay can ensure that the data can be correctly routed to the target node after receiving the data from the previous hop in the following multiple ways: Method 1: Perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the SRAP layer; Method 2: Carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit (abbreviation: PDU) header; Method 3: Use the second local identifier of the remote terminal in the SRAP PDU header; Method 4: Use the first local identifier of the remote terminal in the SRAP PDU header.

[0012] Optionally, performing replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the SRAP layer of the communication interface link relay adaptation protocol includes at least one of the following:

[0013] In the uplink transmission direction, for the received SRAP PDU, replace the first local identifier of the remote terminal included in the SRAP PDU header with the second local identifier of the remote terminal;

[0014] In the downlink transmission direction, for the received SRAP PDU, replace the second local identifier of the remote terminal included in the SRAP PDU header with the first local identifier of the remote terminal.

[0015] In an embodiment of the present application, in the uplink transmission direction, the U2N relay replaces the first local identifier of the remote terminal included in the received SRAP PDU header with the second local identifier of the remote terminal, and routes according to the second local identifier of the remote terminal to ensure that data can be correctly routed to the target node; in the downlink transmission direction, the U2N relay replaces the second local identifier of the remote terminal included in the received SRAP PDU header with the first local identifier of the remote terminal, and routes according to the first local identifier of the remote terminal, so that any U2U relay between the U2N relay and the remote terminal can perform correct routing based on the information included in the SRAP PDU header.

[0016] Optionally, the method further includes:

[0017] In the uplink transmission direction, for the received SRAP PDU, delete the local identifier of the U2N relay included in the SRAP PDU header;

[0018] In the downlink transmission direction, for the received SRAP PDU, add the local identifier of the U2N relay to the SRAP PDU header;

[0019] Wherein, the local identifier of the U2N relay is a local identifier assigned to the U2N relay by any U2U relay between the remote terminal and the U2N relay.

[0020] In an embodiment of the present application, in the uplink transmission direction, the U2N relay deletes the local identifier of the U2N relay included in the SRAP PDU header based on the received SRAP PDU, which can reduce unnecessary SRAP PDU header overhead; in the downlink transmission direction, the U2N relay adds the local identifier of the U2N relay to the SRAP PDU header based on the received SRAP PDU, so that the SRAP PDU contains the local identifier of the U2N relay, and subsequent nodes in the downlink direction can perform correct routing based on the information included in the SRAP PDU header.

[0021] Optionally, 1 bit of indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

[0022] In the embodiments of the present application, while enabling data to be correctly routed to the target node, the end-to-end scenario corresponding to the end-to-end data can be identified through the 1-bit indication information carried in the SRAP PDU header, such as: the terminal-to-network device scenario, or the terminal-to-terminal scenario, so as to perform appropriate processing on the SRAP PDU.

[0023] Optionally, simultaneously carrying the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit (PDU) header includes:

[0024] Generating a new SRAP PDU according to the received SRAP PDU, and simultaneously carrying the first local identifier of the remote terminal and the second local identifier of the remote terminal in the PDU header of the new SRAP PDU.

[0025] In the embodiments of the present application, the U2N relay can generate a new SRAP PDU according to the received SRAP PDU, so that the PDU header of the new SRAP PDU simultaneously carries the first local identifier of the remote terminal and the second local identifier of the remote terminal, realizing correct routing based on the information contained in the SRAP PDU header during the data forwarding process.

[0026] Optionally, the method further includes at least one of the following:

[0027] Notifying the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the first information;

[0028] Notifying any U2U relay between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the second information;

[0029] Notifying the remote terminal of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the third information.

[0030] In an embodiment of the present application, the U2N relay may send a first piece of information to a network device to notify the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay; the U2N relay may send a second piece of information to any U2U relay between the remote terminal and the U2N relay to notify any U2U relay between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay; the U2N relay may also send a third piece of information to the remote terminal to notify the remote terminal of its second local identifier and / or the local identifier corresponding to the U2N relay. By notifying the first local identifier of the remote terminal, the second local identifier of the remote terminal, and the local identifier corresponding to the U2N relay to the corresponding nodes, each node on the transmission path can identify the SRAP PDU header of the forwarded data, thereby ensuring that the data can be correctly routed to the target node.

[0031] Optionally, the first piece of information is carried by radio resource control (RRC) signaling or media access control element (MAC CE) of the Uu interface; the second piece of information and / or the third piece of information is carried by direct communication interface PC5-RRC signaling or sidelink MAC CE.

[0032] In a second aspect, the present application provides a data transmission method in a multi-hop relay scenario, which is applied to a first user equipment to user equipment (U2U) relay. The method includes:

[0033] For a remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, not allocate the first local identifier of the remote terminal to the remote terminal or allocate the first local identifier of the remote terminal to the remote terminal; and / or,

[0034] For the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, not allocate the local identifier corresponding to the U2N relay to the U2N relay or allocate the local identifier corresponding to the U2N relay to the U2N relay;

[0035] Wherein, the first U2U relay is any U2U relay or a designated U2U relay between the remote terminal and the U2N relay.

[0036] In the embodiments of the present application, before the end-to-end connection is established between the remote terminal and the U2N relay, any U2U relay or the designated U2U relay (herein referred to as the first U2U relay, and there is no limitation on how to determine it specifically. For example, it can be the U2U relay connected to the remote terminal or the U2U relay connected to the U2N relay) between the remote terminal and the U2N relay can allocate the first local identifier of the remote terminal to the remote terminal or allocate the corresponding local identifier of the U2N relay to the U2N relay. The purpose is that when data is transmitted between the remote terminal and the U2N relay before the remote terminal and the network device establish a connection, the local identifier can be used, thereby reducing the header overhead of the SRAP PDU. Before the end-to-end connection is established between the remote terminal and the U2N relay, any U2U relay or the designated U2U relay (herein referred to as the first U2U relay, and there is no limitation on how to determine it specifically. For example, it can be the U2U relay connected to the remote terminal or the U2U relay connected to the U2N relay) between the remote terminal and the U2N relay may not allocate the first local identifier of the remote terminal to the remote terminal or allocate the corresponding local identifier of the U2N relay to the U2N relay. In this way, when data is transmitted between the remote terminal and the U2N relay before the remote terminal and the network device establish a connection, the local can be used to carry the L2 address of the remote terminal and the L2 address of the U2N relay in the SRAP PDU.

[0037] Optionally, if the first local identifier of the remote terminal is allocated to the remote terminal, the method further includes:

[0038] Sending fourth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the fourth information includes the first local identifier corresponding to the remote terminal; and / or;

[0039] Sending fifth information to the network device serving the remote terminal, where the fifth information includes the first local identifier of the remote terminal.

[0040] In an embodiment of the present application, the first U2U relay assigns a first local identifier of the remote terminal to the remote terminal, and sends the first local identifier corresponding to the remote terminal to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, and / or sends the first local identifier corresponding to the remote terminal to a network device, so that all communication nodes involved in communication in a multi-hop U2N relay scenario can perform correct routing based on the information included in the SRAP PDU header.

[0041] Optionally, if a local identifier corresponding to the U2N relay is assigned to the U2N relay, the method includes:

[0042] Send sixth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the sixth information includes the local identifier corresponding to the U2N relay; and / or;

[0043] Send seventh information to a network device serving the remote terminal, where the seventh information includes the local identifier corresponding to the U2N relay.

[0044] In an embodiment of the present application, the first U2U relay assigns a local identifier corresponding to the U2N relay to the U2N relay, and sends the local identifier corresponding to the U2N relay (i.e., the local identifier of the U2N relay) to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, and / or sends the local identifier corresponding to the U2N relay to a network device, so that in the data forwarding process, the node receiving the data can perform correct routing based on the information included in the SRAP PDU header.

[0045] Optionally, the method further includes:

[0046] Receive a second local identifier of the remote terminal from a network device, and use the second local identifier of the remote terminal in the SRAP PDU header.

[0047] In an embodiment of the present application, the first U2U relay may receive the second local identifier of the remote terminal from a network device and use the second local identifier of the remote terminal in the SRAP PDU header, so that in the data forwarding process, the node receiving the SRAP PDU can perform correct routing based on the information included in the SRAP PDU header.

[0048] Optionally, the fifth information and / or the seventh information are carried by Uu RRC signaling or MAC CE, and the fourth information and / or the sixth information are carried by PC5-RRC or sidelink MAC CE.

[0049] In a third aspect, the present application provides a data transmission method in a multi-hop relay scenario, which is applied to a network device. The method includes at least one of the following:

[0050] Send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the terminal-to-network relay U2N relay;

[0051] Send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N Relay, and any one U2Urelay between the remote terminal and the U2N relay.

[0052] In the embodiments of the present application, the network device can forward data in a multi-hop relay scenario through the following multiple methods to ensure that the data can be correctly routed to the target node: Method 1: Send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the U2N relay; Method 2: Send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N Relay, and any one U2U relay between the remote terminal and the U2N relay; Method 3: Combine Method 1 and Method 2.

[0053] Optionally, the method further includes:

[0054] In the uplink transmission direction, determine the corresponding Packet Data Convergence Protocol (PDCP) entity according to the second local identifier of the remote terminal carried in the SRAP PDU header.

[0055] In the embodiments of the present application, in the uplink transmission direction, the network device determines the corresponding Packet Data Convergence Protocol (PDCP) entity based on the second local identifier of the remote terminal carried in the SRAP PDU header, which is convenient for forwarding data to the appropriate PDCP entity, so as to ensure that the received SRAP data can be delivered to the correct PDCP entity.

[0056] Optionally, the method further includes at least one of the following:

[0057] Receive the first local identifier of the remote terminal sent by the U2N relay and / or the local identifier corresponding to the U2N relay;

[0058] Receive the first local identifier of the remote terminal sent by any U2U relay between the remote terminal and the U2N relay and / or the local identifier corresponding to the U2N relay;

[0059] Receive the first local identifier of the remote terminal sent by the remote terminal and / or the local identifier corresponding to the U2N relay.

[0060] In the embodiments of the present application, the network device may receive the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay sent by at least one of the U2N relay, any U2U relay between the remote terminal and the U2N relay, and the remote terminal, so that in the data forwarding process, correct routing can be performed based on the information included in the SRAP PDU header.

[0061] Optionally, the method further includes at least one of the following:

[0062] Receive the eighth information sent by the U2N relay, and allocate a corresponding first local identifier for the U2N relay according to the eighth information;

[0063] Send the ninth information to the U2N relay, where the ninth information is used to indicate the correspondence between the first local identifier allocated by the network device for the U2N relay and the local identifier corresponding to the U2N relay.

[0064] In the embodiments of the present application, the network device may receive the eighth information sent by the U2N relay for indicating that the network device allocates a corresponding first local identifier for the U2N relay. The network device allocates a corresponding first local identifier for the U2N relay (here refers to the newly allocated local identifier), and sends the first local identifier allocated for it and the local identifier corresponding to the U2N relay (here refers to the local identifier that the U2N relay originally had / was originally allocated) to the U2N relay, so that correct routing can be performed based on the information included in the SRAP PDU header.

[0065] Optionally, the eighth information and / or the ninth information are carried by Uu interface RRC signaling or MAC CE.

[0066] Optionally, 1 bit of indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

[0067] In the embodiments of the present application, while enabling the data to be correctly routed to the target node, the 1 bit of indication information carried in the SRAP PDU header can identify the end-to-end scenario corresponding to the end-to-end data, such as: the terminal-to-network device scenario, or the terminal-to-terminal scenario, so as to perform appropriate processing on the SRAP PDU.

[0068] In a fourth aspect, the present application provides a data transmission device in a multi-hop relay scenario. The device is applied to a terminal-to-network relay U2N relay, and the device includes:

[0069] A processing unit, configured to perform at least one of the following operations after receiving data from the previous hop node:

[0070] Perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol SRAP layer;

[0071] Simultaneously carry the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit PDU header;

[0072] Use the second local identifier of the remote terminal in the SRAP PDU header;

[0073] Use the first local identifier of the remote terminal in the SRAP PDU header;

[0074] Wherein, in the uplink transmission direction, the previous hop node is a terminal-to-terminal relay U2U relay; in the downlink transmission direction, the previous hop node is a network device; the first local identifier of the remote terminal is a local identifier assigned to the remote terminal by the first U2U relay between the remote terminal and the U2N relay, and the first U2U relay is any one or a specified U2U relay between the remote terminal and the U2N relay, and the second local identifier of the remote terminal is a local identifier assigned to the remote terminal by the network device.

[0075] In the embodiments of the present application, the U2N relay can ensure that data can be correctly routed to the target node after receiving data from the previous hop in the following multiple ways: Way 1: Replace the first local identifier of the remote terminal with the second local identifier of the remote terminal at the SRAP layer; Way 2: Carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP PDU header; Way 3: Use the second local identifier of the remote terminal in the SRAP PDU header; Way 4: Use the first local identifier of the remote terminal in the SRAP PDU header.

[0076] Optionally, the processing unit is specifically configured to perform at least one of the following:

[0077] In the uplink transmission direction, for the received SRAP PDU, replace the first local identifier of the remote terminal included in the SRAP PDU header with the second local identifier of the remote terminal;

[0078] In the downlink transmission direction, for the received SRAP PDU, replace the second local identifier of the remote terminal included in the SRAP PDU header with the first local identifier of the remote terminal.

[0079] In the embodiments of the present application, in the uplink transmission direction, the U2N relay replaces the first local identifier of the remote terminal included in the received SRAP PDU header with the second local identifier of the remote terminal, and routes according to the second local identifier of the remote terminal to ensure that data can be correctly routed to the target node; in the downlink transmission direction, the U2N relay replaces the second local identifier of the remote terminal included in the received SRAP PDU header with the first local identifier of the remote terminal, and routes according to the first local identifier of the remote terminal, so that after the U2N relay and any U2U relay between the remote terminal and the U2N relay receive data from the U2N relay, they can perform correct routing based on the information included in the SRAP PDU header.

[0080] Optionally, the processing unit is further configured to:

[0081] In the uplink transmission direction, for the received SRAP PDU, delete the local identifier of the U2N relay included in the SRAP PDU header;

[0082] In the downlink transmission direction, for the received SRAP PDU, add the local identifier of the U2N relay to the SRAP PDU header;

[0083] Among them, the local identifier of the U2N relay is the local identifier assigned to the U2N relay by any U2U relay between the remote terminal and the U2N relay.

[0084] In an embodiment of the present application, in the uplink transmission direction, the U2N relay deletes the local identifier of the U2N relay included in the SRAP PDU header based on the received SRAP PDU, which can reduce unnecessary SRAP PDU header overhead; in the downlink transmission direction, the U2N relay adds the local identifier of the U2N relay to the SRAP PDU header based on the received SRAP PDU, so that the SRAP PDU contains the local identifier of the U2N relay, and subsequent nodes in the downlink direction can perform correct routing based on the information included in the SRAP PDU header.

[0085] Optionally, 1 bit of indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

[0086] In an embodiment of the present application, while enabling the data to be correctly routed to the target node, the 1 bit of indication information carried in the SRAP PDU header can identify the corresponding end-to-end scenario of the end-to-end data, such as: the terminal-to-network device scenario, or the terminal-to-terminal scenario, so as to perform appropriate processing on the SRAP PDU.

[0087] Optionally, the processing unit is specifically configured to:

[0088] Generate a new SRAP PDU according to the received SRAP PDU, and the PDU header of the new SRAP PDU carries both the first local identifier of the remote terminal and the second local identifier of the remote terminal.

[0089] In an embodiment of the present application, the U2N relay can generate a new SRAP PDU according to the received SRAP PDU, so that the PDU header of the new SRAP PDU carries both the first local identifier of the remote terminal and the second local identifier of the remote terminal, realizing correct routing based on the information included in the SRAP PDU header during the data forwarding process.

[0090] Optionally, the device further includes a sending unit; the sending unit is configured to perform at least one of the following:

[0091] Notify the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the first information;

[0092] Notify any U2U relay between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the second information;

[0093] Notify the remote terminal of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the third information.

[0094] In an embodiment of the present application, the U2N relay may send first information to a network device to notify the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay; the U2N relay may send second information to any U2U relay between the remote terminal and the U2N relay to notify any U2U relay between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay; the U2N relay may also send third information to the remote terminal to notify the remote terminal of its second local identifier and / or the local identifier corresponding to the U2N relay. By notifying the first local identifier of the remote terminal, the second local identifier of the remote terminal, and the local identifier corresponding to the U2N relay to corresponding nodes, the nodes can perform correct routing based on the information included in the SRAP PDU header.

[0095] Optionally, the first information is carried by radio resource control (RRC) signaling or media access control element (MAC CE) of the Uu interface; the second information and / or the third information is carried by direct communication interface PC5-RRC signaling or sidelink MAC CE.

[0096] In a fifth aspect, the present application provides a data transmission device in a multi-hop relay scenario, which is applied to a first terminal-to-terminal relay U2U relay. The device includes:

[0097] A first processing unit, configured to, for a remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, not allocate the first local identifier of the remote terminal to the remote terminal or allocate the first local identifier of the remote terminal to the remote terminal; and / or,

[0098] A second processing unit, configured to, for the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, not allocate the local identifier corresponding to the U2N relay to the U2N relay or allocate the local identifier corresponding to the U2N relay to the U2N relay;

[0099] Among them, the first U2U relay is any U2U relay or a specified U2U relay between the remote terminal and the U2N relay.

[0100] In the embodiments of the present application, before the remote terminal and the U2N relay establish an end-to-end connection, any U2U relay or a specified U2U relay (here referring to the first U2U relay, and there is no limitation on how to determine it specifically. For example, it can be a U2U relay connected to the remote terminal or a U2U relay connected to the U2N relay) between the remote terminal and the U2N relay can allocate the first local identifier of the remote terminal to the remote terminal or allocate the local identifier corresponding to the U2N relay to the U2N relay. The purpose is to use the local identifier when data is transmitted between the remote terminal and the U2N relay before the remote terminal and the network device establish a connection, thereby reducing the header overhead of the SRAP PDU. Before the remote terminal and the U2N relay establish an end-to-end connection, any U2U relay or a specified U2U relay (here referring to the first U2U relay, and there is no limitation on how to determine it specifically. For example, it can be a U2U relay connected to the remote terminal or a U2U relay connected to the U2N relay) between the remote terminal and the U2N relay may not allocate the first local identifier of the remote terminal to the remote terminal or allocate the local identifier corresponding to the U2N relay to the U2N relay. In this way, when data is transmitted between the remote terminal and the U2N relay before the remote terminal and the network device establish a connection, the local can be used to carry the L2 address of the remote terminal and the L2 address of the U2N relay in the SRAP PDU.

[0101] Optionally, the device further includes: a sending unit; the sending unit is configured to, when allocating the first local identifier of the remote terminal to the remote terminal,

[0102] send fourth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the fourth information includes the first local identifier corresponding to the remote terminal; and / or;

[0103] send fifth information to the network device serving the remote terminal, where the fifth information includes the first local identifier of the remote terminal.

[0104] In the embodiment of the present application, the first U2U relay assigns a first local identifier of the remote terminal to the remote terminal, and sends the first local identifier corresponding to the remote terminal to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, and / or sends the first local identifier corresponding to the remote terminal to a network device, so that all communication nodes involved in communication in the multi-hop U2N relay scenario can perform correct routing based on the information included in the SRAP PDU header.

[0105] Optionally, the sending unit is further configured to: when assigning a local identifier corresponding to the U2N relay to the U2N relay,

[0106] send sixth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the sixth information includes the local identifier corresponding to the U2N relay; and / or;

[0107] send seventh information to the network device serving the remote terminal, where the seventh information includes the local identifier corresponding to the U2N relay.

[0108] In the embodiment of the present application, the first U2U relay assigns a local identifier corresponding to the U2N relay to the U2N relay, and sends the local identifier corresponding to the U2N relay (i.e., the local identifier of the U2N relay) to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, and / or sends the local identifier corresponding to the U2N relay to a network device, so that in the data forwarding process, the node receiving the data can perform correct routing based on the information included in the SRAP PDU header.

[0109] Optionally, the apparatus further includes: a receiving unit; the receiving unit is configured to:

[0110] receive a second local identifier of the remote terminal from a network device, and use the second local identifier of the remote terminal in the SRAP PDU header.

[0111] In the embodiment of the present application, the first U2U relay may receive the second local identifier of the remote terminal from a network device and use the second local identifier of the remote terminal in the SRAP PDU header, so that in the data forwarding process, the node receiving the SRAP PDU can perform correct routing based on the information included in the SRAP PDU header.

[0112] Optionally, the fifth information and / or the seventh information is carried by Uu RRC signaling or MAC CE, and the fourth information and / or the sixth information is carried by PC5-RRC or sidelink MAC CE.

[0113] In a sixth aspect, the present application provides a data transmission device in a multi-hop relay scenario, which is applied to a network device. The device includes:

[0114] A first sending unit, configured to send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to a terminal-to-network relay U2N relay; and / or,

[0115] A second sending unit, configured to send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N Relay, and any U2U relay between the remote terminal and the U2N relay.

[0116] In an embodiment of the present application, the network device can implement data forwarding in a multi-hop relay scenario in the following multiple ways to ensure that data can be correctly routed to the target node: Way 1: Send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the U2N relay; Way 2: Send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N Relay, and any U2U relay between the remote terminal and the U2N relay; Way 3: Combine Way 1 and Way 2.

[0117] Optionally, the device further includes: a processing unit; the processing unit is configured to:

[0118] In the uplink transmission direction, determine a corresponding Packet Data Convergence Protocol (PDCP) entity according to the second local identifier of the remote terminal carried in the SRAP PDU header.

[0119] In an embodiment of the present application, in the uplink transmission direction, the network device determines a corresponding Packet Data Convergence Protocol (PDCP) entity based on the second local identifier of the remote terminal carried in the SRAP PDU header, which is convenient for forwarding data to the appropriate PDCP entity, so as to ensure that the received SRAP data can be delivered to the correct PDCP entity.

[0120] Optionally, the device further includes a receiving unit; the receiving unit is configured to perform at least one of the following:

[0121] Receive the first local identifier of the remote terminal sent by the U2N relay and / or the local identifier corresponding to the U2N relay;

[0122] Receive the first local identifier of the remote terminal sent by any U2U relay between the remote terminal and the U2N relay and / or the local identifier corresponding to the U2N relay;

[0123] Receive the first local identifier of the remote terminal sent by the remote terminal and / or the local identifier corresponding to the U2N relay.

[0124] In the embodiments of the present application, the network device may receive the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay sent by at least one of the U2N relay, any U2U relay between the remote terminal and the U2N relay, and the remote terminal, so that in the data forwarding process, correct routing can be performed based on the information included in the SRAP PDU header.

[0125] Optionally, the processing unit is further configured to perform at least one of the following:

[0126] Receive the eighth information sent by the U2N relay, and allocate a corresponding first local identifier for the U2N relay according to the eighth information;

[0127] Send the ninth information to the U2N relay, where the ninth information is used to indicate the correspondence between the first local identifier allocated by the network device for the U2N relay and the local identifier corresponding to the U2N relay.

[0128] In the embodiments of the present application, the network device may receive the eighth information sent by the U2N relay for indicating that the network device allocates a corresponding first local identifier for the U2N relay. The network device allocates a corresponding first local identifier for the U2N relay (here referring to the newly allocated local identifier), and sends the first local identifier allocated for it and the local identifier corresponding to the U2N relay (here referring to the local identifier that the U2N relay originally had / was originally allocated) to the U2N relay, so that correct routing can be performed based on the information included in the SRAP PDU header.

[0129] Optionally, the eighth information and / or the ninth information is carried by Uu interface RRC signaling or MAC CE.

[0130] Optionally, 1 bit of indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

[0131] In the embodiments of the present application, while enabling the data to be correctly routed to the target node, through the 1 bit of indication information carried in the SRAP PDU header, the corresponding end-to-end scenario can be identified, such as: the terminal-to-network device scenario, or the terminal-to-terminal scenario, so as to perform appropriate processing on the SRAP PDU.

[0132] In a seventh aspect, the present application provides a data transmission device in a multi-hop relay scenario. The device is applied to a terminal-to-network relay U2N relay, and the device includes a memory, a transceiver, and a processor:

[0133] The memory is used to store computer programs; the transceiver is used to send and receive data under the control of the processor; the processor is used to read the computer programs in the memory and perform the following operations:

[0134] After receiving data from the previous hop node, perform at least one of the following operations:

[0135] Perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol SRAP layer;

[0136] Carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit PDU header;

[0137] Use the second local identifier of the remote terminal in the SRAP PDU header;

[0138] Use the first local identifier of the remote terminal in the SRAP PDU header;

[0139] Wherein, in the uplink transmission direction, the previous hop node is a terminal-to-terminal relay U2U relay; in the downlink transmission direction, the previous hop node is a network device; the first local identifier of the remote terminal is a local identifier assigned to the remote terminal by the first U2U relay between the remote terminal and the U2N relay, and the first U2U relay is any U2U relay or a designated U2U relay between the remote terminal and the U2N relay, and the second local identifier of the remote terminal is a local identifier assigned to the remote terminal by the network device.

[0140] In the embodiments of the present application, the U2N relay can ensure that the data can be correctly routed to the target node after receiving the data from the previous hop in the following multiple ways: Way 1: Replace the first local identifier of the remote terminal with the second local identifier of the remote terminal at the SRAP layer; Way 2: Carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP PDU header; Way 3: Use the second local identifier of the remote terminal in the SRAP PDU header; Way 4: Use the first local identifier of the remote terminal in the SRAP PDU header.

[0141] Optionally, when the processor is used to replace the first local identifier of the remote terminal with the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol (SRAP) layer, it specifically includes at least one of the following:

[0142] In the uplink transmission direction, for the received SRAP PDU, replace the first local identifier of the remote terminal included in the SRAP PDU header with the second local identifier of the remote terminal;

[0143] In the downlink transmission direction, for the received SRAP PDU, replace the second local identifier of the remote terminal included in the SRAP PDU header with the first local identifier of the remote terminal.

[0144] In the embodiments of the present application, in the uplink transmission direction, the U2N relay replaces the first local identifier of the remote terminal included in the received SRAP PDU header with the second local identifier of the remote terminal, and routes according to the second local identifier of the remote terminal to ensure that the data can be correctly routed to the target node; in the downlink transmission direction, the U2N relay replaces the second local identifier of the remote terminal included in the received SRAP PDU header with the first local identifier of the remote terminal, and routes according to the first local identifier of the remote terminal, so that after the U2N relay and any U2U relay between the remote terminal and the U2N relay receive the data from the U2N relay, they can perform correct routing based on the information included in the SRAP PDU header.

[0145] Optionally, the processor is further configured to perform the following operations:

[0146] In the uplink transmission direction, for the received SRAP PDU, delete the local identifier of the U2N relay included in the SRAP PDU header;

[0147] In the downlink transmission direction, for the received SRAP PDU, add the local identifier of the U2N relay to the SRAP PDU header;

[0148] Wherein, the local identifier of the U2N relay is a local identifier assigned to the U2N relay by any U2U relay between the remote terminal and the U2N relay.

[0149] In the embodiments of the present application, in the uplink transmission direction, based on the received SRAP PDU, the U2N relay deletes the local identifier of the U2N relay included in the SRAP PDU header, which can reduce unnecessary SRAP PDU header overhead; in the downlink transmission direction, based on the received SRAP PDU, the U2N relay adds the local identifier of the U2N relay to the SRAP PDU header, so that the SRAP PDU contains the local identifier of the U2N relay, and subsequent nodes in the downlink direction can perform correct routing based on the information included in the SRAP PDU header.

[0150] Optionally, 1-bit indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

[0151] In the embodiments of the present application, while enabling the data to be correctly routed to the target node, through the 1-bit indication information carried in the SRAP PDU header, the corresponding end-to-end scenario can be identified, such as: the terminal-to-network device scenario, or the terminal-to-terminal scenario, so as to perform appropriate processing on the SRAP PDU.

[0152] Optionally, when the processor is used to carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit PDU header, it specifically includes:

[0153] Generate a new SRAP PDU according to the received SRAP PDU, and both the first local identifier of the remote terminal and the second local identifier of the remote terminal are carried in the PDU header of the new SRAP PDU.

[0154] In the embodiments of the present application, the U2N relay can generate a new SRAP PDU according to the received SRAP PDU, so that both the first local identifier of the remote terminal and the second local identifier of the remote terminal are carried in the PDU header of the new SRAP PDU, realizing correct routing based on the information included in the SRAP PDU header during the data forwarding process.

[0155] Optionally, the processor is further configured to perform at least one of the following:

[0156] Notify the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the first information;

[0157] Notify any one of the U2U relays between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the second information;

[0158] Notify the remote terminal of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the third information.

[0159] In an embodiment of the present application, the U2N relay may send the first information to the network device to notify the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay; the U2N relay may send the second information to any one of the U2U relays between the remote terminal and the U2N relay to notify any one of the U2U relays between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay; the U2N relay may further send the third information to the remote terminal to notify the remote terminal of its second local identifier and / or the local identifier corresponding to the U2N relay. By notifying the first local identifier of the remote terminal, the second local identifier of the remote terminal, and the local identifier corresponding to the U2N relay to the corresponding nodes, the nodes can perform correct routing based on the information included in the SRAP PDU header.

[0160] Optionally, the first information is carried by radio resource control (RRC) signaling or media access control unit (MAC) CE over the Uu interface; the second information and / or the third information are carried by direct communication interface (PC5)-RRC signaling or sidelink MAC CE.

[0161] In an eighth aspect, the present application provides a data transmission device in a multi-hop relay scenario, which is applied to a first terminal-to-terminal relay U2U relay. The device includes: a memory, a transceiver, and a processor:

[0162] The memory is configured to store a computer program; the transceiver is configured to transmit and receive data under the control of the processor; the processor is configured to read the computer program in the memory and perform the following operations:

[0163] For the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, the first local identifier of the remote terminal is not allocated to the remote terminal or the first local identifier of the remote terminal is allocated to the remote terminal; and / or,

[0164] For the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, the local identifier corresponding to the U2N relay is not allocated to the U2N relay or the local identifier corresponding to the U2N relay is allocated to the U2N relay;

[0165] Wherein, the first U2U relay is any U2U relay or a specified U2U relay between the remote terminal and the U2N relay.

[0166] In the embodiments of the present application, before establishing an end-to-end connection between the remote terminal and the U2N relay, any U2U relay or a specified U2U relay (referred to as the first U2U relay here) between the remote terminal and the U2N relay is not limited to how to be determined specifically. For example, it can be a U2U relay connected to the remote terminal or a U2U relay connected to the U2N relay) can allocate the first local identifier of the remote terminal to the remote terminal or allocate the local identifier corresponding to the U2N relay to the U2N relay. The purpose is to use the local identifier when data is transmitted between the remote terminal and the U2N relay before the remote terminal establishes a connection with the network device, thereby reducing the header overhead of the SRAP PDU. Before establishing an end-to-end connection between the remote terminal and the U2N relay, any U2U relay or a specified U2U relay (referred to as the first U2U relay here, and how to be determined specifically is not limited. For example, it can be a U2U relay connected to the remote terminal or a U2U relay connected to the U2N relay) may not allocate the first local identifier of the remote terminal to the remote terminal or allocate the local identifier corresponding to the U2N relay to the U2N relay, so that when data is transmitted between the remote terminal and the U2N relay before the remote terminal establishes a connection with the network device, the local can be used to carry the L2 address of the remote terminal and the L2 address of the U2N relay in the SRAP PDU.

[0167] Optionally, when the processor is used to allocate the first local identifier of the remote terminal to the remote terminal, it is further used to perform the following operations:

[0168] Send the fourth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the fourth information includes the first local identifier corresponding to the remote terminal; and / or;

[0169] Send the fifth information to the network device serving the remote terminal, where the fifth information includes the first local identifier of the remote terminal.

[0170] In the embodiments of the present application, the first U2U relay assigns the first local identifier of the remote terminal to the remote terminal, sends the first local identifier corresponding to the remote terminal to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, and / or sends the first local identifier corresponding to the remote terminal to the network device, so that all communication nodes involved in communication in the multi-hop U2N relay scenario can perform correct routing based on the information included in the SRAP PDU header.

[0171] Optionally, when the processor is used to assign a local identifier corresponding to the U2N relay to the U2N relay, it is further used to perform the following operations:

[0172] Send the sixth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the sixth information includes the local identifier corresponding to the U2N relay; and / or;

[0173] Send the seventh information to the network device serving the remote terminal, where the seventh information includes the local identifier corresponding to the U2N relay.

[0174] In the embodiments of the present application, the first U2U relay assigns the local identifier corresponding to the U2N relay to the U2N relay, sends the local identifier corresponding to the U2N relay (i.e., the local identifier of the U2N relay) to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, and / or sends the local identifier corresponding to the U2N relay to the network device, so that correct routing can be performed based on the information included in the SRAP PDU header during the data forwarding process.

[0175] Optionally, the processor is further used to perform the following operations:

[0176] Receive the second local identifier of the remote terminal from the network device and use the second local identifier of the remote terminal in the SRAP PDU header.

[0177] In the embodiments of the present application, the first U2U relay may receive the second local identifier of the remote terminal from a network device and use the second local identifier of the remote terminal in the SRAP PDU header, so that correct routing can be performed based on the information contained in the SRAP PDU header during the data forwarding process.

[0178] Optionally, the fifth information and / or the seventh information are carried by Uu RRC signaling or MAC CE, and the fourth information and / or the sixth information are carried by PC5-RRC or sidelink MAC CE.

[0179] In a ninth aspect, the present application provides a data transmission device in a multi-hop relay scenario, which is applied to a network device. The device includes: a memory, a transceiver, and a processor:

[0180] The memory is used to store computer programs; the transceiver is used to transmit and receive data under the control of the processor; the processor is used to read the computer programs in the memory and perform at least one of the following operations:

[0181] Send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the terminal-to-network relay U2N relay;

[0182] Send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N relay, and any one of the U2U relays between the remote terminal and the U2N relay.

[0183] In the embodiments of the present application, the network device can implement data forwarding in a multi-hop relay scenario in the following multiple ways to ensure that data can be correctly routed to the target node: Way 1: Send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the U2N relay; Way 2: Send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N relay, and any one of the U2U relays between the remote terminal and the U2N relay; Way 3: Combine Way 1 and Way 2.

[0184] Optionally, the processor is further configured to perform the following operation: in the uplink transmission direction, determine the corresponding packet data convergence protocol (PDCP) entity according to the second local identifier of the remote terminal carried in the SRAP PDU header.

[0185] In an embodiment of the present application, in the uplink transmission direction, the network device determines a corresponding Packet Data Convergence Protocol (PDCP) entity based on the second local identifier of the remote terminal carried in the SRAP PDU header, facilitating the forwarding of data to the appropriate PDCP entity, thereby ensuring that the received SRAP data is delivered to the correct PDCP entity.

[0186] Optionally, the processor is further configured to perform at least one of the following operations:

[0187] Receive the first local identifier of the remote terminal sent by the U2N relay and / or the local identifier corresponding to the U2N relay;

[0188] Receive the first local identifier of the remote terminal sent by any U2U relay between the remote terminal and the U2N relay and / or the local identifier corresponding to the U2N relay;

[0189] Receive the first local identifier of the remote terminal sent by the remote terminal and / or the local identifier corresponding to the U2N relay.

[0190] In an embodiment of the present application, the network device may receive the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay sent by at least one of the U2N relay, any U2U relay between the remote terminal and the U2N relay, and the remote terminal, enabling correct routing based on the information contained in the SRAP PDU header during the data forwarding process.

[0191] Optionally, the processor is further configured to perform at least one of the following operations:

[0192] Receive the eighth information sent by the U2N relay, and allocate a corresponding first local identifier to the U2N relay according to the eighth information;

[0193] Send the ninth information to the U2N relay, where the ninth information is used to indicate the correspondence between the first local identifier allocated by the network device to the U2N relay and the local identifier corresponding to the U2N relay.

[0194] In an embodiment of the present application, a network device may receive eighth information sent by a U2N relay for instructing the network device to allocate a corresponding first local identifier to the U2N relay. The network device allocates a corresponding first local identifier to the U2N relay (here, it refers to the newly allocated local identifier), and sends the allocated first local identifier and the local identifier corresponding to the U2N relay (here, it refers to the local identifier that the U2N relay already had / was previously allocated) to the U2N relay, and can perform correct routing based on the information included in the SRAP PDU header.

[0195] Optionally, the eighth information and / or the ninth information is carried by Uu interface RRC signaling or MAC CE.

[0196] Optionally, a 1-bit indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

[0197] In an embodiment of the present application, while enabling the data to be correctly routed to the target node, the 1-bit indication information carried in the SRAP PDU header can identify the corresponding end-to-end scenario, such as: the terminal-to-network device scenario, or the terminal-to-terminal scenario, so as to perform appropriate processing on the SRAP PDU.

[0198] In a tenth aspect, the present application provides a non-transitory readable storage medium storing a computer program, and the computer program is used to cause a processor to execute the method described in any one of the above.

[0199] The present application provides a data transmission method and apparatus in a multi-hop relay scenario. After receiving data from the previous hop node, any of the following operations is performed: replacing the first local identifier of the remote terminal and the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol (SRAP) layer; carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit (PDU) header; using the second local identifier of the remote terminal in the SRAP PDU header; using the first local identifier of the remote terminal in the SRAP PDU header; wherein, in the uplink transmission direction, the previous hop node is a user-to-user (U2U) relay from the terminal to the network; in the downlink transmission direction, the previous hop node is a network device; the first local identifier of the remote terminal is a local identifier assigned to the remote terminal by a first U2U relay between the remote terminal and the U2N relay, and the first U2U relay is any U2U relay or a specified U2U relay between the remote terminal and the U2N relay; the second local identifier of the remote terminal is a local identifier assigned to the remote terminal by the network device. Therefore, through the above various methods, it is possible to enable the U2N relay to perform correct routing based on the information contained in the SRAP PDU header after receiving data from the previous hop.

[0200] It should be understood that the content described in the above invention content section is not intended to limit the key or important features of the embodiments of the present application, nor to limit the scope of the present application. Other features of the present application will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0201] In order to more clearly illustrate the technical solutions in the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0202] Figure 1 It is a schematic flowchart of the data transmission method in a multi-hop relay scenario provided by an embodiment of the present application;

[0203] Figure 2 It is an interaction schematic diagram of the data transmission method in a multi-hop relay scenario provided by an embodiment of the present application;

[0204] Figure 3 It is a schematic diagram of the SRAP PDU format provided by an embodiment of the present application Figure 1 ;

[0205] Figure 4 Schematic diagram of the SRAP PDU format provided by the embodiments of the present application Figure 2 ;

[0206] Figure 5 Schematic diagram of the SRAP PDU format provided by the embodiments of the present application Figure 3 ;

[0207] Figure 6 Interaction schematic diagram of the data transmission method in the multi-hop relay scenario provided by another embodiment of the present application;

[0208] Figure 7 Schematic diagram of the SRAP PDU format provided by the embodiments of the present application Figure 4 ;

[0209] Figure 8 Interaction schematic diagram of the data transmission method in the multi-hop relay scenario provided by yet another embodiment of the present application;

[0210] Figure 9 Schematic diagram of the SRAP PDU format provided by the embodiments of the present application Figure 5 ;

[0211] Figure 10 Schematic diagram of the structure of the data transmission device in the multi-hop relay scenario provided by the embodiments of the present application;

[0212] Figure 11 One of the schematic diagrams of the structure of the data transmission device in the multi-hop relay scenario provided by the embodiments of the present application;

[0213] Figure 12 Another schematic diagram of the structure of the data transmission device in the multi-hop relay scenario provided by the embodiments of the present application;

[0214] Figure 13 Yet another schematic diagram of the structure of the data transmission device in the multi-hop relay scenario provided by the embodiments of the present application;

[0215] Figure 14 Fourth schematic diagram of the structure of the data transmission device in the multi-hop relay scenario provided by the embodiments of the present application. Detailed implementation manners

[0216] In the embodiments of the present application, the term "and / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after.

[0217] In the embodiments of the present application, the term "a plurality of" refers to two or more, and other quantifiers are similar thereto.

[0218] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0219] To clearly understand the technical solutions of the present application, the solutions of the prior art will be introduced in detail first.

[0220] In a multi-hop U2N relay scenario, the data of a remote terminal needs to be forwarded to a network device through N (N is greater than or equal to 1) U2U relays and one U2N relay at the same time. In this case, since the local identifier assigned to the U2U relay for the U2U relay and the local identifier assigned to the U2N relay by the network device (such as a base station) are completely two independent identifiers, if the U2N relay processes according to the existing protocol, after the U2N relay receives data from the previous-hop U2U relay, the local identifier assigned by the U2U relay and the local identifier assigned by the network device cannot be associated at the direct communication interface link relay adaptation protocol SRAP layer. Therefore, it is impossible to ensure that the data can be correctly routed to the target node, resulting in communication interruption.

[0221] To solve the problem that the prior art cannot ensure that the data is correctly routed to the target node in a multi-hop U2N relay scenario, any one of the following methods can be used: replacing the local identifier of the remote terminal by the U2N relay, the SRAP PDU carrying both the first local identifier and the second local identifier of the remote terminal, using only the first local identifier, using only the second local identifier, etc. After receiving data from the previous hop, correct routing can be achieved based on the information contained in the SRAP PDU header.

[0222] Therefore, based on the above research, the data transmission method and device in a multi-hop relay scenario proposed in the present application are proposed. In the present application, the following various methods can be used to achieve correct routing based on the information contained in the SRAP PDU header after receiving data from the previous hop: Method 1: Perform replacement between the first local identifier and the second local identifier of the remote terminal at the SRAP layer; Method 2: Carry both the first local identifier and the second local identifier of the remote terminal in the SRAP PDU header; Method 3: Use the second local identifier of the remote terminal in the SRAP PDU header; Method 4: Use the first local identifier of the remote terminal in the SRAP PDU header.

[0223] Among them, the method and the apparatus are based on the same application concept. Since the principles of the method and the apparatus for solving problems are similar, the implementation of the apparatus and the method can be referred to each other, and the repeated parts will not be described again.

[0224] Embodiments of the present application will be described below with reference to the accompanying drawings.

[0225] See Figure 1 as shown Figure 1 It is a schematic flowchart of a data transmission method in a multi-hop relay scenario provided by an embodiment of the present application. The execution subject of the data transmission method in the multi-hop relay scenario provided by this embodiment is a terminal-to-network relay U2N relay. The multi-hop relay scenario includes a remote terminal, at least one U2U relay, one U2N relay, and a network device (such as a base station).

[0226] In the uplink transmission direction, the previous-hop node is a terminal-to-terminal relay U2U relay; in the downlink transmission direction, the previous-hop node is a network device; the first local identifier of the remote terminal is a local identifier assigned to the remote terminal by the first U2U relay between the remote terminal and the U2N relay, and the first U2U relay is any U2U relay or a specified U2U relay between the remote terminal and the U2N relay; the second local identifier of the remote terminal is a local identifier assigned to the remote terminal by the network device.

[0227] Among them, there are various ways to determine the specified U2U relay. For example, the specified U2U relay can be the first U2U relay connected to the remote terminal (Remote UE) or the first U2U relay connected to the U2N relay, which is not limited in this application.

[0228] The data transmission method in the multi-hop relay scenario provided by the embodiment of the present application includes the following steps: after receiving data from the previous-hop node, perform any one of the following operations:

[0229] Step 101: Perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol SRAP layer.

[0230] Among them, the U2N relay performs replacement of the local identifier of the remote terminal (including the first identifier and the second identifier of the remote terminal). The first local identifier of the remote terminal can be assigned by the first U2U relay, and the second local identifier of the remote terminal can be assigned by the base station.

[0231] Step 102: Carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit (PDU) header.

[0232] The SRAP PDU header carries both the first local identifier of the remote terminal and the second local identifier of the remote terminal. The first local identifier of the remote terminal can be assigned by the first U2U relay, and the second local identifier of the remote terminal can be assigned by the base station. Meanwhile, it is necessary to interact the first local identifier of the remote terminal and the second local identifier of the remote terminal between different nodes.

[0233] Step 103: Use the second local identifier of the remote terminal in the SRAP PDU header.

[0234] Completely use the first local identifier of the remote terminal, where the first local identifier of the remote terminal can be assigned by the first U2U relay and needs to be notified to the network device.

[0235] Step 104: Use the first local identifier of the remote terminal in the SRAP PDU header.

[0236] Completely use the second local identifier of the remote terminal. The second local identifier of the remote terminal can be directly assigned by the network device; or, the first U2U relay first assigns the first local identifier of the remote terminal and then notifies the network device. The network device can determine the second local identifier of the remote terminal according to the first local identifier of the remote terminal. After assigning the second local identifier of the remote terminal, only the second local identifier of the remote terminal is used.

[0237] In the embodiments of the present application, the U2N relay can achieve correct routing based on the information included in the SRAP PDU header after receiving data from the previous hop through the following multiple methods: Method 1: Perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the SRAP layer; Method 2: Carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP PDU header; Method 3: Use the second local identifier of the remote terminal in the SRAP PDU header; Method 4: Use the first local identifier of the remote terminal in the SRAP PDU header.

[0238] Optionally, the replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol (SRAP) layer includes at least one of the following:

[0239] In the uplink transmission direction, for the received SRAP PDU, replace the first local identifier of the remote terminal included in the SRAP PDU header with the second local identifier of the remote terminal;

[0240] In the downlink transmission direction, for the received SRAP PDU, replace the second local identifier of the remote terminal included in the SRAP PDU header with the first local identifier of the remote terminal.

[0241] In an embodiment of the present application, in the uplink transmission direction, the U2N relay replaces the first local identifier of the remote terminal included in the received SRAP PDU header with the second local identifier of the remote terminal, and routes according to the second local identifier of the remote terminal, so that after the network device receives data from the U2N relay, it can perform correct routing based on the information included in the SRAP PDU header; in the downlink transmission direction, the U2N relay replaces the second local identifier of the remote terminal included in the received SRAP PDU header with the first local identifier of the remote terminal, and routes according to the first local identifier of the remote terminal, so that after the U2N relay and any U2U relay between the remote terminal and the U2N relay receive data from the U2N relay, they can perform correct routing based on the information included in the SRAP PDU header.

[0242] Optionally, the method further includes:

[0243] In the uplink transmission direction, for the received SRAP PDU, delete the local identifier of the U2N relay included in the SRAP PDU header;

[0244] In the downlink transmission direction, for the received SRAP PDU, add the local identifier of the U2N relay to the SRAP PDU header;

[0245] Wherein, the local identifier of the U2N relay is a local identifier assigned to the U2N relay by any U2U relay between the remote terminal and the U2N relay.

[0246] In the embodiments of the present application, based on the above method 1, the replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal is performed at the SRAP layer. In the uplink transmission direction, the U2N relay deletes the local identifier of the U2N relay included in the SRAP PDU header based on the received SRAP PDU, which can reduce unnecessary SRAP PDU header overhead. In the downlink transmission direction, the U2N relay adds the local identifier of the U2N relay to the SRAP PDU header based on the received SRAP PDU, so that the SRAP PDU contains the local identifier of the U2N relay, and subsequent nodes in the downlink direction can perform correct routing based on the information included in the SRAP PDU header.

[0247] Optionally, 1 bit of indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

[0248] In the embodiments of the present application, while enabling the data to be correctly routed to the target node, the 1 bit of indication information carried in the SRAP PDU header can identify the corresponding end-to-end scenario, such as: the terminal-to-network device scenario or the terminal-to-terminal scenario, so as to perform appropriate processing on the SRAP PDU.

[0249] The following uses specific embodiments to elaborate in detail on the data transmission method in a multi-hop relay scenario.

[0250] Exemplarily, Embodiment 1 (performing replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the SRAP layer)

[0251] See Figure 2 as shown Figure 2 is an interaction diagram of the data transmission method in a multi-hop relay scenario provided by the embodiments of the present application. The data transmission method in the multi-hop relay scenario provided by this embodiment includes the following steps:

[0252] Step 1-2c: The remote terminal discovers through the relay discovery process that it can access the network device (here referring to the base station, such as: gNB) in a multi-hop relay manner through multiple U2U relays (for example, U2U relay1 and U2U relay2) and 1 U2N relay, and then establishes a direct communication interface PC5 connection corresponding to each hop in the multi-hop connection.

[0253] Among them, Step 1: The remote terminal discovers through the relay discovery process;

[0254] Step 2a: Establish a PC5 connection between the remote terminal and U2U relay1;

[0255] Step 2b: Establish a PC5 connection between U2U relay1 and U2U relay2;

[0256] Step 2c: Establish a PC5 connection between U2U relay2 and U2N relay.

[0257] Step 3: At least one U2U relay between the remote terminal and the U2N relay assigns the first local identifier corresponding to the remote terminal (i.e., the first local identifier of the remote terminal) to the remote terminal, and assigns the local identifier corresponding to the U2N relay to the U2N relay.

[0258] Step 4: Optional step, establish an end-to-end connection between the remote terminal and the U2N relay (i.e., End-to-End PC5 Connection Establishment). (This step is not mandatory)

[0259] Step 5: The remote terminal sends an RRC connection establishment request to the network device.

[0260] When transmitting this end-to-end connection establishment request, a pre-configured PC5 Radio Link Control (RLC) channel can be used.

[0261] Steps 6-7: After receiving this end-to-end connection establishment request, the U2N relay requests the network device to assign the second local identifier corresponding to the remote terminal (i.e., the second local identifier of the remote terminal) to the remote terminal.

[0262] Among them, Step 6: The U2N relay requests the network device (here referring to gNB) to assign a local identifier to the remote terminal;

[0263] Step 7: The network device assigns a local identifier to the remote terminal.

[0264] Specifically, the U2N relay can request the network device to assign the second local identifier corresponding to the remote terminal to the remote terminal through Sidelink UE Information.

[0265] The network device assigns the second local identifier corresponding to the remote terminal to the remote terminal.

[0266] Step 8: The U2N relay forwards the RRC connection establishment request sent by the remote terminal to the network device.

[0267] Step 9: The network device sends an RRC connection establishment message to the remote terminal.

[0268] Optionally, after step 9, the network device may send an RRC reconfiguration message to the remote terminal, etc. Since this is an existing process, it will not be described in detail.

[0269] Step 10: The remote terminal sends uplink data to the U2N relay.

[0270] Among them, the first local identifier of the remote terminal and the local identifier of the U2N relay are carried in the SRAP PDU header of the uplink data.

[0271] An example of the SRAP PDU format is as Figure 3 shown, where UE ID 1 is the first local identifier of the remote terminal and UE ID is the local identifier of the U2N relay.

[0272] Steps 11 - 12: The U2N relay performs replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the SRAP layer, and sends the processed data to the network device.

[0273] Among them, in step 11: The U2N relay exchanges (or replaces) the first local identifier of the remote terminal in the uplink SRAP PDU header with the second local identifier of the remote terminal;

[0274] In step 12: The U2N relay sends the uplink data to the network device.

[0275] For the uplink (i.e., in the uplink transmission direction), the U2N relay replaces the first local identifier of the remote terminal with the second local identifier of the remote terminal at the SRAP layer. Optionally, for the uplink, the U2N relay deletes the local identifier of the U2N relay at the SRAP layer;

[0276] Specifically, whether the above operation is processed on the SRAP sending side or the SRAP receiving side depends on the implementation of the U2N relay.

[0277] An example of the processed SRAP PDU format is as Figure 4 shown, where UE ID 2 (for SRC) is the second local identifier of the remote terminal.

[0278] Step 13: The network device sends downlink data to the terminal.

[0279] An example of the SRAP PDU format is as Figure 4 shown, where UE ID 2 is the second local identifier of the remote terminal.

[0280] Steps 14 - 15: The U2N relay performs replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the SRAP layer, and sends the processed data to the remote terminal.

[0281] Among them, in step 14: The U2N relay replaces the second local identifier of the remote terminal in the downlink SRAP PDU header with the first local identifier of the remote terminal;

[0282] In step 15: The U2N relay sends downlink data to the remote terminal.

[0283] For the downlink (i.e., in the downlink transmission direction), the second local identifier of the remote terminal is replaced with the first local identifier of the remote terminal at the SRAP layer. Optionally, for the downlink, the local identifier of the U2N relay is added at the SRAP layer;

[0284] An example of the SRAP PDU format is as Figure 5 shown, where UE ID 1 is the first local identifier of the remote terminal, and UE ID is the local identifier of the U2N relay.

[0285] Specifically, whether the above operations are processed on the SRAP sending side or the SRAP receiving side depends on the implementation of the U2N relay.

[0286] Optionally, for the downlink, 1 bit of indication information can also be carried in the SRAP PDU header, which is used to indicate whether the data type is for the U2N relay scenario or the U2U relay scenario. So that the remote terminal can deliver the data to the appropriate Packet Data Convergence Protocol (PDCP) entity (i.e., the PDCP entity) after receiving the data.

[0287] Optionally, simultaneously carrying the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit PDU header includes:

[0288] Generating a new SRAP PDU according to the received SRAP PDU, and the PDU header of the new SRAP PDU simultaneously carries the first local identifier of the remote terminal and the second local identifier of the remote terminal.

[0289] In the embodiments of the present application, the U2N relay can generate a new SRAP PDU according to the received SRAP PDU, so that the PDU header of the new SRAP PDU carries both the first local identifier of the remote terminal and the second local identifier of the remote terminal, realizing that in the data forwarding process, correct routing can be performed based on the information contained in the SRAP PDU header.

[0290] Optionally, the method further includes at least one of the following:

[0291] Notifying the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the first information;

[0292] Notifying any U2U relay between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the second information;

[0293] Notifying the remote terminal of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the third information.

[0294] In the embodiments of the present application, based on Method 2, when both the first local identifier of the remote terminal and the second local identifier of the remote terminal are carried in the SRAP protocol data unit PDU header, the U2N relay can send the first information to the network device to notify the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay; the U2N relay can send the second information to any U2U relay between the remote terminal and the U2N relay to notify any U2U relay between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay; the U2N relay can also send the third information to the remote terminal to notify the remote terminal of its second local identifier and / or the local identifier corresponding to the U2N relay. By notifying the first local identifier of the remote terminal, the second local identifier of the remote terminal, and the local identifier corresponding to the U2N relay to the corresponding nodes, the nodes can perform correct routing based on the information contained in the SRAP PDU header.

[0295] Optionally, based on Mode 2, the first local identifier of the remote terminal and the second local identifier of the remote terminal are simultaneously carried in the SRAP protocol data unit (PDU) header. It further includes: for the uplink, the network device determines the corresponding PDCP entity according to the second local identifier of the remote terminal carried in the SRAP PDU header; for the downlink, the remote terminal determines to deliver the relevant data to the corresponding PDCP entity according to the second local identifier of the remote terminal carried in the SRAP PDU header.

[0296] Optionally, it further includes: the U2N relay needs to notify the correspondence between the second local identifier of the remote terminal and the first local identifier of the remote terminal to the remote terminal and one or more U2U relays between the remote terminal and the U2N relay.

[0297] Optionally, the first information is carried by the radio resource control (RRC) signaling or the media access control unit (MAC) CE of the Uu interface; the second information and / or the third information are carried by the direct communication interface PC5-RRC signaling or the sidelink MAC CE.

[0298] Optionally, for Mode 2, simultaneously carrying the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit (PDU) header can be implemented by any of the following methods:

[0299] Method 21: In the downlink transmission direction, when the network device (such as a base station) sends data to the U2N relay, only the second local identifier is carried. The U2N relay processes the received SRAP PDU and adds the first local identifier.

[0300] Method 22: In the downlink transmission direction, when the base station generates the SRAP PDU, it simultaneously includes the first local identifier and the second local identifier.

[0301] Method 23: In the uplink transmission direction, the data received by the U2N relay from the U2U relay only contains the first local identifier. The U2N relay adds the second local identifier and then sends it to the network device (such as a base station).

[0302] Method 24: In the uplink transmission direction, when the remote terminal generates the SRAP PDU, it directly carries the first local identifier and the second local identifier.

[0303] Exemplarily, in Embodiment 2 (for Mode 2, simultaneously carrying the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit (PDU) header, and using the same SRAP PDU header for each hop)

[0304] See Figure 6 as shown Figure 6 This is an interactive schematic diagram of the data transmission method in a multi-hop relay scenario provided by another embodiment of the present application. The data transmission method in the multi-hop relay scenario provided by this embodiment includes the following steps:

[0305] Step 1-2c: The remote terminal discovers through the relay discovery process that it can access the network device (here referring to the base station, such as: gNB) in a multi-hop relay manner through multiple U2U relays (for example, U2U relay1 and U2U relay2) and 1 U2N relay, and then establishes a direct communication interface PC5 connection corresponding to each hop in the multi-hop connection.

[0306] Among them, Step 1: The remote terminal discovers through the relay discovery process;

[0307] Step 2a: Establish a PC5 connection between the remote terminal and U2U relay1;

[0308] Step 2b: Establish a PC5 connection between U2U relay1 and U2U relay2;

[0309] Step 2c: Establish a PC5 connection between U2U relay2 and U2N relay.

[0310] Step 3: At least one U2U relay between the remote terminal and the U2N relay assigns a first local identifier corresponding to the remote terminal to the remote terminal and assigns a local identifier corresponding to the U2N relay to the U2N relay.

[0311] Step 4: Optional step, establish an end-to-end connection between the remote terminal and the U2N relay. (This step is not necessary)

[0312] Step 5: The remote terminal sends an RRC connection establishment request to the network device

[0313] When transmitting this end-to-end connection establishment request, a pre-configured PC5 RLC channel can be used.

[0314] Steps 6-7: After receiving the end-to-end connection establishment request, the U2N relay requests the network device to assign a second local identifier corresponding to the remote terminal to the remote terminal.

[0315] Among them, Step 6: The U2N relay requests the network device (here referring to gNB) to assign a local identifier to the remote terminal;

[0316] Step 7: The network device assigns a local identifier to the remote terminal.

[0317] Specifically, the U2N relay may request the network device to allocate a second local identifier corresponding to the remote terminal for the remote terminal through Sidelink UE Information.

[0318] Optionally, the U2N relay or the U2U relay that allocates the first local identifier for the remote terminal needs to notify the network device of the first local identifier corresponding to the remote terminal and / or the local identifier corresponding to the U2N relay.

[0319] Step 8: The U2N relay forwards the RRC connection establishment request sent by the remote terminal to the network device.

[0320] Step 9: The network device sends an RRC connection establishment message to the terminal.

[0321] Optionally, after Step 9, the network device may send an RRC reconfiguration message, etc. to the remote terminal. Since it is an existing process, it will not be described in detail.

[0322] Step 10: The terminal and the network device perform uplink / downlink data transmission through multi-hop relays.

[0323] Among them, the first local identifier of the remote terminal and the second local identifier of the remote terminal are carried in the SRAP PDU header of the SRAP layer at the same time. Taking the uplink (here referring to the uplink transmission direction) as an example, the SRAP PDU format is shown as Figure 7 shown. Wherein: UEID 1 is the first local identifier of the remote terminal, UE ID is the local identifier of the U2N relay, and UE ID 2 is the second local identifier of the remote terminal.

[0324] For uplink / downlink data transmission, when the data is transmitted between U2U relays or between a U2U relay and a U2N relay, the U2U relay may ignore the second local identifier of the remote terminal included in the SRAP PDU header. When the data is transmitted between the U2N relay and the base station, the first local identifier of the remote terminal included in the SRAP PDU header may be ignored.

[0325] For the uplink, the network device receives the data from the U2N relay and determines the corresponding PDCP entity according to the second local identifier corresponding to the remote terminal included therein.

[0326] For the downlink, the remote terminal determines to deliver the relevant data to the corresponding PDCP entity according to the second local identifier of the remote terminal carried in the SRAP PDU header.

[0327] Exemplarily, in Embodiment 3 (for Method 2, both the first local identifier of the remote terminal and the second local identifier of the remote terminal are carried in the SRAP protocol data unit (PDU) header. For uplink, the U2N relay adds the second local identifier of the remote terminal to the SRAP PDU header; for downlink, the U2N relay adds the first local identifier of the remote terminal to the SRAP PDU header).

[0328] As shown in combination with Figure 6 the data transmission method in the multi-hop relay scenario provided in this embodiment includes the following steps:

[0329] Step 1-2c: The remote terminal discovers through the relay discovery process that it can access the network device in a multi-hop relay manner through multiple U2U relays (for example, U2U relay1 and U2U relay2) and 1 U2N relay, and then establishes a direct communication interface PC5 connection corresponding to each hop in the multi-hop connection.

[0330] Among them, in Step 1: The remote terminal discovers through the relay discovery process;

[0331] Step 2a: Establish a PC5 connection between the remote terminal and U2U relay1;

[0332] Step 2b: Establish a PC5 connection between U2U relay1 and U2U relay2;

[0333] Step 2c: Establish a PC5 connection between U2U relay2 and U2N relay.

[0334] Step 3: At least one U2U relay between the remote terminal and the U2N relay respectively assigns the first local identifier corresponding to the remote terminal to the remote terminal, and assigns the local identifier corresponding to the U2N relay to the U2N relay.

[0335] Step 4: An optional step is to establish an end-to-end connection between the remote terminal and the U2N relay. (This step is not necessary).

[0336] Step 5: The remote terminal sends an RRC connection establishment request to the network device.

[0337] When transmitting this end-to-end connection establishment request, a pre-configured PC5 RLC channel can be used.

[0338] Steps 6-7: After receiving the end-to-end connection establishment request, the U2N relay requests the network device to assign the second local identifier corresponding to the remote terminal to the remote terminal.

[0339] Among them, step 6: The U2N relay requests the network device (here it refers to the gNB) to allocate a local identifier for the remote terminal;

[0340] Step 7: The network device allocates a local identifier for the remote terminal.

[0341] Specifically, the U2N relay can request the network device to allocate the second local identifier corresponding to the remote terminal for the remote terminal through Sidelink UE Information.

[0342] Optionally, the U2N relay or the U2U relay that allocates the first local identifier for the remote terminal needs to notify the network device of the first local identifier corresponding to the remote terminal and / or the local identifier corresponding to the U2N relay.

[0343] Step 8: The U2N relay forwards the RRC connection establishment request sent by the remote terminal to the network device.

[0344] Step 9: The network device sends an RRC connection establishment message to the terminal.

[0345] Optionally, after step 9, the network device can send an RRC reconfiguration message, etc. to the remote terminal. Since it is an existing process, it will not be described in detail.

[0346] Step 10: The terminal and the network device perform uplink / downlink data transmission through multi-hop relays.

[0347] For the uplink, the SRAP PDU format of the data received by the U2U relay from the U2U relay is as Figure 3 shown.

[0348] The SRAP layer of the U2U relay needs to add the second local identifier UE ID2 of the remote terminal in the SRAP PDU header to generate an SRAP PDU in the format as Figure 7 shown. It should be noted that this PDU format is only an exemplary schematic diagram, and the order of each field does not need to be restricted during specific implementation. In order to identify different SDAP PDU header formats, 1 Rbit in the SRAP PDU header can be used to indicate the specific format.

[0349] For the downlink, the SRAP PDU format received by the U2N relay from the network device is as Figure 4 shown.

[0350] The SRAP layer of the U2U relay needs to add the first local identifier of the remote terminal in the SRAP PDU header. Optionally, it also needs to add the local identifier of the relay terminal to generate as Figure 7The SRAP PDU in the shown format. It should be noted that this PDU format is only an exemplary schematic diagram, and the order of each field does not need to be restricted during specific implementation. To identify different SDAP PDU header formats, 1 Rbit in the SRAP PDU header can be used to indicate the specific format.

[0351] For the uplink, the network device receives data from the U2N relay and determines the corresponding PDCP entity according to the second local identifier of the remote terminal contained therein.

[0352] For the downlink, the remote terminal determines to deliver the relevant data to the corresponding PDCP entity according to the second local identifier of the remote terminal carried in the SRAP PDU header.

[0353] Optionally, based on Method 3, using the second local identifier of the remote terminal in the SRAP PDU header, and based on Method 4, using the first local identifier of the remote terminal in the SRAP PDU header, it further includes at least one of the following:

[0354] 1) For the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, the U2U relay between the remote terminal and the U2N relay does not allocate the first local identifier of the remote terminal and / or does not allocate the local identifier corresponding to the U2N relay for the U2N relay;

[0355] 2) For the remote end, before establishing an end-to-end connection between the remote terminal and the U2N relay, the U2U relay between the remote terminal and the U2N relay allocates the first local identifier of the remote terminal and / or allocates the local identifier corresponding to the U2N relay for the U2N relay.

[0356] Optionally, the local identifier of the U2N relay is allocated by the network device.

[0357] Optionally, the U2N relay needs to notify the remote terminal and one or more U2U relays between the remote terminal and the U2N relay of the correspondence between the second local identifier and the first local identifier of the U2N relay.

[0358] Exemplarily, Embodiment 4 (the base station allocates the second local identifier of the remote terminal, and the U2U relay does not allocate the first local identifier of the remote terminal)

[0359] See Figure 8 as shown Figure 8Interaction schematic diagram of the data transmission method in a multi-hop relay scenario provided by another embodiment of this application. The data transmission method in the multi-hop relay scenario provided by this embodiment includes the following steps:

[0360] Step 1-2c: The remote terminal discovers through the relay discovery process that it can access the network device in a multi-hop relay manner through multiple U2U relays (for example, U2U relay1 and U2U relay2) and 1 U2N relay, and then establishes a direct communication interface PC5 connection corresponding to each hop in the multi-hop connection.

[0361] Among them, Step 1: The remote terminal discovers through the relay discovery process;

[0362] Step 2a: Establish a PC5 connection between the remote terminal and U2U relay1;

[0363] Step 2b: Establish a PC5 connection between U2U relay1 and U2U relay2;

[0364] Step 2c: Establish a PC5 connection between U2U relay2 and U2N relay.

[0365] Step 3: Optional step, establish an end-to-end connection between the remote terminal and the U2N relay. (This step is not necessary)

[0366] Step 4: The remote terminal sends an RRC connection establishment request to the network device.

[0367] When transmitting this end-to-end connection establishment request, a pre-configured PC5 RLC channel can be used.

[0368] Steps 5-6: After receiving the end-to-end connection establishment request, the U2N relay requests the network device to allocate a second local identifier corresponding to the remote terminal for the remote terminal.

[0369] Among them, Step 5: The U2N relay requests the network device (here it refers to gNB) to allocate a local identifier for the remote terminal;

[0370] Step 6: The network device allocates a local identifier for the remote terminal.

[0371] Specifically, the U2N relay can request the network device to allocate a second local identifier corresponding to the remote terminal for the remote terminal through Sidelink UE Information. Optionally, it can also request the network device to allocate a second local identifier corresponding to the U2N relay for the U2N relay.

[0372] Step 7: The U2N relay forwards the RRC connection establishment request sent by the remote terminal to the network device.

[0373] Step 8: The network device sends an RRC connection establishment message to the terminal.

[0374] Optionally, after step 8, the network device may send an RRC reconfiguration message to the remote terminal, etc. Since it is an existing process, it will not be described in detail.

[0375] Step 9: The terminal and the network device perform uplink / downlink data transmission through multi-hop relay.

[0376] For the uplink, an example of the SRAP PDU format of the data received by the U2U relay from the U2U relay is as Figure 3 shown, where both UE ID 1 and UE ID are assigned by the network device.

[0377] After the SRAP layer of the U2U relay receives the SRAP PDU, when forwarding the data to the network, it may optionally delete the UE ID (for DST) therein.

[0378] For the downlink, an example of the SRAP PDU format of the data received by the U2N relay from the network device is as Figure 9 shown, where UE ID 1 is assigned by the network device.

[0379] After the SRAP layer of the U2N relay receives the SRAP PDU, when forwarding the data to the U2U relay, it may add the local identifier corresponding to the U2N relay in the SRAP PDU. See Figure 5 shown.

[0380] Exemplarily, in Embodiment 5 (the base station assigns a second local identifier to the remote terminal, and the U2U relay assigns a first local identifier to the remote terminal)

[0381] Combined with Figure 6 shown, the data transmission method in the multi-hop relay scenario provided in this embodiment includes the following steps:

[0382] Step 1-2c: The remote terminal discovers through the relay discovery process that it can access the network device in a multi-hop relay manner through multiple U2U relays (for example, U2U relay1 and U2U relay2) and 1 U2N relay, and then establishes a direct communication interface PC5 connection corresponding to each hop in the multi-hop connection.

[0383] Among them, step 1: The remote terminal passes through the relay discovery process;

[0384] Step 2a: Establish a PC5 connection between the remote terminal and U2U relay1;

[0385] Step 2b: Establish a PC5 connection between U2U relay1 and U2U relay2;

[0386] Step 2c: Establish a PC5 connection between U2U relay2 and U2N relay.

[0387] Step 3: At least one U2U relay between the remote terminal and U2N relay assigns a first local identifier corresponding to the remote terminal to the remote terminal respectively, and assigns a local identifier corresponding to the U2N relay to the U2N relay.

[0388] Step 4: Optional step, establish an end-to-end connection between the remote terminal and U2N relay. (This step is not mandatory)

[0389] Step 5: The remote terminal sends an RRC connection establishment request to the network device.

[0390] When transmitting this end-to-end connection establishment request, a pre-configured PC5 RLC channel can be used.

[0391] Steps 6 - 7: After receiving the end-to-end connection establishment request, the U2N relay requests the network device to assign a second local identifier corresponding to the remote terminal to the remote terminal.

[0392] Among them, Step 6: The U2N relay requests the network device (here it refers to gNB) to assign a local identifier to the remote terminal;

[0393] Step 7: The network device assigns a local identifier to the remote terminal.

[0394] Specifically, the U2N relay can request the network device to assign a second local identifier corresponding to the remote terminal to the remote terminal through Sidelink UE Information. Optionally, it can also request the network device to assign a second local identifier corresponding to the U2N relay to the U2N relay.

[0395] Once obtaining the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay, it is necessary to notify the remote terminal and each U2U relay between the remote terminal and the U2N relay. Subsequently, the SRAP layer can only use the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay assigned by the network device.

[0396] Step 8: The U2N relay forwards the RRC connection establishment request sent by the remote terminal to the network device.

[0397] Step 9: The network device sends an RRC connection establishment message to the terminal.

[0398] Optionally, after Step 9, the network device may send an RRC reconfiguration message to the remote terminal, etc. Since this is an existing process, it will not be described in detail.

[0399] Step 10: The terminal and the network device perform uplink / downlink data transmission through multi-hop relay.

[0400] For the uplink, an example of the SRAP PDU format of the data received by the U2U relay from the U2U relay is as Figure 3 shown, where at least UE ID 1 is assigned by the network. Optionally, the local identifier UE ID of the U2N relay may be assigned by the U2U relay or by the network device.

[0401] Optionally, after the SRAP layer of the U2U relay receives the SRAP PDU, when forwarding the data to the network, it may optionally delete the UE ID (for DST) therein.

[0402] For the downlink, an example of the SRAP PDU format of the data received by the U2U relay from the network device is as Figure 9 shown, where UE ID 1 is assigned by the network device.

[0403] If the local identifier of the U2N relay is not included in the above SRAP PDU, after the SRAP layer of the U2N relay receives the SRAP PDU, when forwarding the data to the U2U relay, it may add the corresponding local identifier of the U2N relay to the SRAP PDU. See Figure 5 shown.

[0404] Therefore, in the embodiments of the present application, through the following multiple methods, namely Method 1: performing replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the SRAP layer; Method 2: simultaneously carrying the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit (English: Protocol Data Unit, abbreviated as: PDU) header; Method 3: using the second local identifier of the remote terminal in the SRAP PDU header; Method 4: using the first local identifier of the remote terminal in the SRAP PDU header. It is possible to correctly route based on the information contained in the SRAP PDU header after receiving data from the previous hop.

[0405] Another embodiment of the present application provides a data transmission method in a multi-hop relay scenario, which is applied to a first user-to-user (U2U) relay. The method includes:

[0406] For a remote terminal, before establishing an end-to-end connection between the remote terminal and a U2N relay, either not allocate a first local identifier of the remote terminal to the remote terminal or allocate the first local identifier of the remote terminal to the remote terminal; and / or,

[0407] For the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, either not allocate a local identifier corresponding to the U2N relay to the U2N relay or allocate the local identifier corresponding to the U2N relay to the U2N relay;

[0408] Wherein, the first U2U relay is any U2U relay or a specified U2U relay between the remote terminal and the U2N relay.

[0409] In an embodiment of the present application, before establishing an end-to-end connection between a remote terminal and a U2N relay, any U2U relay or a specified U2U relay (referred to as the first U2U relay here, and there is no limitation on how to determine it specifically. For example, it can be a U2U relay connected to the remote terminal or a U2U relay connected to the U2N relay) between the remote terminal and the U2N relay can allocate the first local identifier of the remote terminal to the remote terminal or allocate the local identifier corresponding to the U2N relay to the U2N relay. The purpose is to use the local identifier when transmitting data between the remote terminal and the U2N relay before the remote terminal establishes a connection with a network device, thereby reducing the header overhead of the SRAP PDU. Before establishing an end-to-end connection between the remote terminal and the U2N relay, any U2U relay or a specified U2U relay (referred to as the first U2U relay here, and there is no limitation on how to determine it specifically. For example, it can be a U2U relay connected to the remote terminal or a U2U relay connected to the U2N relay) between the remote terminal and the U2N relay may not allocate the first local identifier of the remote terminal to the remote terminal or allocate the local identifier corresponding to the U2N relay to the U2N relay. In this way, when transmitting data between the remote terminal and the U2N relay before the remote terminal establishes a connection with a network device, the local can be used to carry the L2 address of the remote terminal and the L2 address of the U2N relay in the SRAP PDU.

[0410] Optionally, if a first local identifier of the remote terminal is assigned to the remote terminal, the method further includes:

[0411] Sending fourth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the fourth information includes the first local identifier corresponding to the remote terminal; and / or;

[0412] Sending fifth information to a network device serving the remote terminal, where the fifth information includes the first local identifier of the remote terminal.

[0413] In an embodiment of the present application, the first U2U relay assigns the first local identifier of the remote terminal to the remote terminal, sends the first local identifier corresponding to the remote terminal to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, and / or sends the first local identifier corresponding to the remote terminal to the network device, so that all communication nodes involved in communication in a multi-hop U2N relay scenario can perform correct routing based on the information included in the SRAP PDU header.

[0414] Optionally, if a local identifier corresponding to the U2N relay is assigned to the U2N relay, the method includes:

[0415] Sending sixth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the sixth information includes the local identifier corresponding to the U2N relay; and / or;

[0416] Sending seventh information to a network device serving the remote terminal, where the seventh information includes the local identifier corresponding to the U2N relay.

[0417] In an embodiment of the present application, the first U2U relay assigns the local identifier corresponding to the U2N relay to the U2N relay, sends the local identifier corresponding to the U2N relay (i.e., the local identifier of the U2N relay) to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, and / or sends the local identifier corresponding to the U2N relay to the network device, so that in the data forwarding process, the received data can perform correct routing based on the information included in the SRAP PDU header.

[0418] Optionally, the method further includes:

[0419] Receive the second local identifier of the remote terminal from a network device, and use the second local identifier of the remote terminal in the SRAP PDU header.

[0420] In the embodiments of this application, the first U2U relay can receive the second local identifier of the remote terminal from a network device and use the second local identifier of the remote terminal in the SRAP PDU header. In this way, during the data forwarding process, the node that receives the SRAP PDU can perform correct routing based on the information contained in the SRAP PDU header.

[0421] Optionally, the fifth information and / or the seventh information are carried by Uu RRC signaling or MAC CE, and the fourth information and / or the sixth information are carried by PC5-RRC or sidelink MAC CE.

[0422] It should be noted here that for the data transmission method in the multi-hop relay scenario with the first U2U relay as the execution entity provided in this application, the specific implementation process can refer to Figures 2 - 9 the embodiments shown, and the specific implementation process will not be elaborated here.

[0423] Another embodiment of this application provides a data transmission method in a multi-hop relay scenario, which is applied to a network device. The method includes at least one of the following:

[0424] Send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the terminal-to-network relay U2N relay;

[0425] Send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N Relay, and any U2U relay between the remote terminal and the U2N relay.

[0426] In the embodiments of this application, the network device can implement data forwarding in the multi-hop relay scenario in the following multiple ways to ensure that the data can be correctly routed to the target node: Method 1: Send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the U2N relay; Method 2: Send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N Relay, and any U2U relay between the remote terminal and the U2N relay; Method 3: Combine Method 1 and Method 2.

[0427] Optionally, the method further includes:

[0428] In the uplink transmission direction, a corresponding Packet Data Convergence Protocol (PDCP) entity is determined according to the second local identifier of the remote terminal carried in the SRAP PDU header.

[0429] In an embodiment of the present application, in the uplink transmission direction, a network device determines a corresponding Packet Data Convergence Protocol (PDCP) entity based on the second local identifier of the remote terminal carried in the SRAP PDU header, which facilitates forwarding data to the appropriate PDCP entity, thereby ensuring that the received SRAP data is delivered to the correct PDCP entity.

[0430] Optionally, the method further includes at least one of the following:

[0431] Receiving the first local identifier of the remote terminal sent by the U2N relay and / or the local identifier corresponding to the U2N relay;

[0432] Receiving the first local identifier of the remote terminal sent by any U2U relay between the remote terminal and the U2N relay and / or the local identifier corresponding to the U2N relay;

[0433] Receiving the first local identifier of the remote terminal sent by the remote terminal and / or the local identifier corresponding to the U2N relay.

[0434] In an embodiment of the present application, a network device may receive the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay sent by at least one of the U2N relay, any U2U relay between the remote terminal and the U2N relay, and the remote terminal, so that in the data forwarding process, correct routing can be performed based on the information included in the SRAP PDU header.

[0435] Optionally, the method further includes at least one of the following:

[0436] Receiving the eighth information sent by the U2N relay, and allocating a corresponding first local identifier to the U2N relay according to the eighth information;

[0437] Sending the ninth information to the U2N relay, where the ninth information is used to indicate the correspondence between the first local identifier allocated to the U2N relay by the network device and the local identifier corresponding to the U2N relay.

[0438] In the embodiments of the present application, a network device may receive eighth information sent by a U2N relay for instructing the network device to allocate a corresponding first local identifier to the U2N relay. The network device allocates a corresponding first local identifier to the U2N relay (here, it refers to the newly allocated local identifier), and sends the allocated first local identifier and the local identifier corresponding to the U2N relay (here, it refers to the local identifier that the U2N relay already had / was already allocated) to the U2N relay, and can perform correct routing based on the information included in the SRAP PDU header.

[0439] Optionally, the eighth information and / or the ninth information is carried by Uu interface RRC signaling or MAC CE.

[0440] Optionally, 1 bit of indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

[0441] In the embodiments of the present application, while enabling the data to be correctly routed to the target node, through the 1 bit of indication information carried in the SRAP PDU header, the corresponding end-to-end scenario can be identified, such as: the terminal-to-network device scenario, or the terminal-to-terminal scenario, so as to perform appropriate processing on the SRAP PDU.

[0442] It should be noted here that for the data transmission method in the multi-hop relay scenario with the network device as the execution entity provided by the present application, the specific implementation process can refer to Figures 2 - 9 the embodiments shown, and the specific implementation process will not be elaborated here.

[0443] Figure 10 FIG. is a schematic structural diagram of a data transmission device in a multi-hop relay scenario provided by an embodiment of the present application. As Figure 10 shown, the data transmission device in the multi-hop relay scenario provided in this embodiment is applied to the terminal-to-network relay U2N relay. Then, the data transmission device in the multi-hop relay scenario provided in this embodiment includes: a transceiver 1000, configured to receive and send data under the control of a processor 1010.

[0444] Among them, in Figure 10Among them, the bus architecture may include any number of interconnected buses and bridges, and various circuits of one or more processors represented by the processor 1010 and the memory represented by the memory 1020 are specifically linked together. The bus architecture can also link together various other circuits such as peripheral devices, voltage regulators, 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. The transceiver 1000 may be multiple components, that is, including a transmitter and a receiver, and provides a unit for communicating with various other devices on a transmission medium, and these transmission mediums include wireless channels, wired channels, optical fiber cables, and other transmission mediums. For different user devices, the user interface 1030 may also be an interface capable of externally connecting and internally connecting required devices, and the connected devices include but are not limited to a keypad, a display, a speaker, a microphone, a joystick, etc.

[0445] The processor 1010 is responsible for managing the bus architecture and general processing, and the memory 1020 can store data used by the processor 1010 when executing operations.

[0446] Optionally, the processor 1010 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a complex programmable logic device (CPLD), and the processor may also adopt a multi-core architecture.

[0447] The processor 1010 is used to execute any of the methods provided in the embodiments of the present application according to the obtained executable instructions by calling the program stored in the memory 1020. The processor 1010 and the memory 1020 may also be physically separated.

[0448] In this embodiment, the memory 1020 is used to store a computer program; the transceiver 1000 is used to transmit and receive data under the control of the processor; the processor 1010 is used to read the computer program in the memory and perform the following operations:

[0449] After receiving data from the previous hop node, perform at least one of the following operations:

[0450] Perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol SRAP layer;

[0451] Simultaneously carry the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit PDU header;

[0452] Use the second local identifier of the remote terminal in the SRAP PDU header;

[0453] Use the first local identifier of the remote terminal in the SRAP PDU header;

[0454] Wherein, in the uplink transmission direction, the previous hop node is a terminal-to-terminal relay U2U relay; in the downlink transmission direction, the previous hop node is a network device; the first local identifier of the remote terminal is a local identifier assigned to the remote terminal by a first U2U relay between the remote terminal and the U2N relay, and the first U2U relay is any U2U relay or a specified U2U relay between the remote terminal and the U2N relay, and the second local identifier of the remote terminal is a local identifier assigned to the remote terminal by the network device.

[0455] In the embodiments of the present application, the U2N relay can achieve correct routing based on the information included in the SRAP PDU header after receiving data from the previous hop through the following multiple methods: Method 1, perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the SRAP layer; Method 2, carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP PDU header; Method 3, use the second local identifier of the remote terminal in the SRAP PDU header; Method 4, use the first local identifier of the remote terminal in the SRAP PDU header.

[0456] Optionally, when the processor 1010 is used to perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol SRAP layer, it specifically includes at least one of the following:

[0457] In the uplink transmission direction, for the received SRAP PDU, replace the first local identifier of the remote terminal included in the SRAP PDU header with the second local identifier of the remote terminal;

[0458] In the downlink transmission direction, for the received SRAP PDU, replace the second local identifier of the remote terminal included in the SRAP PDU header with the first local identifier of the remote terminal.

[0459] In an embodiment of the present application, in the uplink transmission direction, the U2N relay replaces the first local identifier of the remote terminal included in the received SRAP PDU header with the second local identifier of the remote terminal, and routes according to the second local identifier of the remote terminal, so that after the network device receives data from the U2N relay, it can perform correct routing based on the information included in the SRAP PDU header; in the downlink transmission direction, the U2N relay replaces the second local identifier of the remote terminal included in the received SRAP PDU header with the first local identifier of the remote terminal, and routes according to the first local identifier of the remote terminal, so that any U2U relay between the U2N relay and the remote terminal can perform correct routing based on the information included in the SRAP PDU header after receiving data from the U2N relay.

[0460] Optionally, the processor 1010 is further configured to perform the following operations:

[0461] In the uplink transmission direction, for the received SRAP PDU, delete the local identifier of the U2N relay included in the SRAP PDU header;

[0462] In the downlink transmission direction, for the received SRAP PDU, add the local identifier of the U2N relay to the SRAP PDU header;

[0463] Wherein, the local identifier of the U2N relay is a local identifier assigned to the U2N relay by any U2U relay between the remote terminal and the U2N relay.

[0464] In an embodiment of the present application, in the uplink transmission direction, the U2N relay deletes the local identifier of the U2N relay included in the SRAP PDU header based on the received SRAP PDU, which can reduce unnecessary SRAP PDU header overhead; in the downlink transmission direction, the U2N relay adds the local identifier of the U2N relay to the SRAP PDU header based on the received SRAP PDU, so that the SRAP PDU includes the local identifier of the U2N relay, and subsequent nodes in the downlink direction can perform correct routing based on the information included in the SRAP PDU header.

[0465] Optionally, 1 bit of indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

[0466] In the embodiments of the present application, while enabling data to be correctly routed to the target node, the 1-bit indication information carried in the SRAP PDU header can be used to identify the corresponding end-to-end scenario, such as: the terminal-to-network device scenario or the terminal-to-terminal scenario, so as to perform appropriate processing on the SRAP PDU.

[0467] Optionally, when the processor 1010 is used to carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit (PDU) header, it specifically includes:

[0468] Generating a new SRAP PDU according to the received SRAP PDU, where both the first local identifier of the remote terminal and the second local identifier of the remote terminal are carried in the PDU header of the new SRAP PDU.

[0469] In the embodiments of the present application, the U2N relay can generate a new SRAP PDU according to the received SRAP PDU, so that both the first local identifier of the remote terminal and the second local identifier of the remote terminal are carried in the PDU header of the new SRAP PDU, realizing correct routing based on the information contained in the SRAP PDU header during the data forwarding process.

[0470] Optionally, the processor 1010 is further configured to perform at least one of the following:

[0471] Notifying the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the first information;

[0472] Notifying any U2U relay between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the second information;

[0473] Notifying the remote terminal of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the third information.

[0474] In an embodiment of the present application, the U2N relay may send a first piece of information to a network device to notify the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay; the U2N relay may send a second piece of information to any one of the U2U relays between the remote terminal and the U2N relay to notify any one of the U2U relays between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay; the U2N relay may further send a third piece of information to the remote terminal to notify the remote terminal of its second local identifier and / or the local identifier corresponding to the U2N relay. By notifying the first local identifier of the remote terminal, the second local identifier of the remote terminal, and the local identifier corresponding to the U2N relay to the corresponding nodes, the nodes can perform correct routing based on the information included in the SRAP PDU header.

[0475] Optionally, the first piece of information is carried by Radio Resource Control (RRC) signaling or Media Access Control Element (MAC CE) on the Uu interface; the second piece of information and / or the third piece of information is carried by ProSe Radio Resource Control (PC5-RRC) signaling or Sidelink MAC CE on the direct communication interface.

[0476] It should be noted here that the data transmission device in the multi-hop relay scenario provided in the present application can implement all the method steps implemented in the method embodiment described in the first aspect above, and can achieve the same technical effects. The same parts and beneficial effects as those in the method embodiment will not be specifically described in this embodiment.

[0477] Figure 11 FIG. 1100 is a schematic structural diagram of a data transmission device in a multi-hop relay scenario provided in an embodiment of the present application. The data transmission device in the multi-hop relay scenario provided in this embodiment is applied to a terminal-to-network relay U2N relay. The data transmission device 1100 in the multi-hop relay scenario provided in this embodiment includes:

[0478] A processing unit 1101, configured to, after receiving data from the previous-hop node, perform at least one of the following operations:

[0479] Perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the Service Relay Adaptation Protocol (SRAP) layer of the direct communication interface link;

[0480] Carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP Protocol Data Unit (PDU) header;

[0481] Use the second local identifier of the remote terminal in the SRAP PDU header;

[0482] Use the first local identifier of the remote terminal in the SRAP PDU header;

[0483] Wherein, in the uplink transmission direction, the previous hop node is the terminal-to-terminal relay U2U relay; in the downlink transmission direction, the previous hop node is a network device; the first local identifier of the remote terminal is a local identifier assigned to the remote terminal by a first U2U relay between the remote terminal and the U2N relay, and the first U2U relay is any U2U relay or a specified U2U relay between the remote terminal and the U2N relay, and the second local identifier of the remote terminal is a local identifier assigned to the remote terminal by the network device.

[0484] In the embodiments of the present application, the U2N relay can achieve correct routing based on the information included in the SRAP PDU header after receiving data from the previous hop through the following multiple methods: Method 1: Perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the SRAP layer; Method 2: Carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP PDU header; Method 3: Use the second local identifier of the remote terminal in the SRAP PDU header; Method 4: Use the first local identifier of the remote terminal in the SRAP PDU header.

[0485] Optionally, the processing unit 1101 is specifically configured to perform at least one of the following:

[0486] In the uplink transmission direction, for the received SRAP PDU, replace the first local identifier of the remote terminal included in the SRAP PDU header with the second local identifier of the remote terminal;

[0487] In the downlink transmission direction, for the received SRAP PDU, replace the second local identifier of the remote terminal included in the SRAP PDU header with the first local identifier of the remote terminal.

[0488] In an embodiment of the present application, in the uplink transmission direction, the U2N relay replaces the first local identifier of the remote terminal included in the received SRAP PDU header with the second local identifier of the remote terminal, and routes according to the second local identifier of the remote terminal, so that after the network device receives data from the U2N relay, it can perform correct routing based on the information included in the SRAP PDU header; in the downlink transmission direction, the U2N relay replaces the second local identifier of the remote terminal included in the received SRAP PDU header with the first local identifier of the remote terminal, and routes according to the first local identifier of the remote terminal, so that any U2U relay between the U2N relay and the remote terminal can perform correct routing based on the information included in the SRAP PDU header after receiving data from the U2N relay.

[0489] Optionally, the processing unit 1101 is further configured to:

[0490] In the uplink transmission direction, for the received SRAP PDU, delete the local identifier of the U2N relay included in the SRAP PDU header;

[0491] In the downlink transmission direction, for the received SRAP PDU, add the local identifier of the U2N relay to the SRAP PDU header;

[0492] Wherein, the local identifier of the U2N relay is a local identifier assigned to the U2N relay by any U2U relay between the remote terminal and the U2N relay.

[0493] In an embodiment of the present application, in the uplink transmission direction, the U2N relay deletes the local identifier of the U2N relay included in the SRAP PDU header based on the received SRAP PDU, which can reduce unnecessary SRAP PDU header overhead; in the downlink transmission direction, the U2N relay adds the local identifier of the U2N relay to the SRAP PDU header based on the received SRAP PDU, so that the SRAP PDU contains the local identifier of the U2N relay, and subsequent nodes in the downlink direction can perform correct routing based on the information included in the SRAP PDU header.

[0494] Optionally, 1 bit of indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

[0495] In the embodiments of the present application, while enabling data to be correctly routed to the target node, the corresponding end-to-end scenario can be identified through the 1-bit indication information carried in the SRAP PDU header, such as: the terminal-to-network device scenario, or the terminal-to-terminal scenario, so as to perform appropriate processing on the SRAP PDU.

[0496] Optionally, the processing unit 1101 is specifically configured to:

[0497] Generate a new SRAP PDU according to the received SRAP PDU, and the PDU header of the new SRAP PDU carries both the first local identifier of the remote terminal and the second local identifier of the remote terminal.

[0498] In the embodiments of the present application, the U2N relay can generate a new SRAP PDU according to the received SRAP PDU, so that the PDU header of the new SRAP PDU carries both the first local identifier of the remote terminal and the second local identifier of the remote terminal, realizing correct routing based on the information contained in the SRAP PDU header during the data forwarding process.

[0499] Optionally, the device further includes a sending unit; the sending unit is configured to perform at least one of the following:

[0500] Notify the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the first information;

[0501] Notify any U2U relay between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the second information;

[0502] Notify the remote terminal of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the third information.

[0503] In an embodiment of the present application, the U2N relay may send a first piece of information to a network device to notify the network device of the first local identifier of a remote terminal and / or the local identifier corresponding to the U2N relay; the U2N relay may send a second piece of information to any U2U relay between the remote terminal and the U2N relay to notify any U2U relay between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay; the U2N relay may further send a third piece of information to the remote terminal to notify the remote terminal of its second local identifier and / or the local identifier corresponding to the U2N relay. By notifying the first local identifier of the remote terminal, the second local identifier of the remote terminal, and the local identifier corresponding to the U2N relay to the corresponding nodes, the nodes can perform correct routing based on the information included in the SRAP PDU header.

[0504] Optionally, the first piece of information is carried by radio resource control (RRC) signaling or media access control element (MAC CE) of the Uu interface; the second piece of information and / or the third piece of information is carried by direct communication interface PC5-RRC signaling or sidelink MAC CE.

[0505] It should be noted here that the data transmission device in the multi-hop relay scenario provided by the present application can implement all the method steps implemented by the method embodiment described in the first aspect above, and can achieve the same technical effects. The same parts and beneficial effects as those in the method embodiment will not be specifically described in this embodiment.

[0506] Combined Figure 10 As shown in the figure, another embodiment of the present application provides a data transmission device in a multi-hop relay scenario. The data transmission device in the multi-hop relay scenario provided in this embodiment is applied to the first terminal-to-terminal relay U2U relay. Then, the data transmission device in the multi-hop relay scenario provided in this embodiment includes:

[0507] A memory, a transceiver, and a processor:

[0508] The memory is used to store a computer program; the transceiver is used to send and receive data under the control of the processor; the processor is used to read the computer program in the memory and perform the following operations:

[0509] For a remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, do not allocate the first local identifier of the remote terminal to the remote terminal or allocate the first local identifier of the remote terminal to the remote terminal; and / or,

[0510] For the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, do not allocate the local identifier corresponding to the U2N relay to the U2N relay or allocate the local identifier corresponding to the U2N relay to the U2N relay;

[0511] Wherein, the first U2U relay is any U2U relay or a specified U2U relay between the remote terminal and the U2N relay.

[0512] In the embodiments of the present application, before establishing an end-to-end connection between the remote terminal and the U2N relay, any U2U relay or a specified U2U relay (referred to as the first U2U relay here, and there is no limitation on how to determine it specifically, for example, it can be a U2U relay connected to the remote terminal or a U2U relay connected to the U2N relay) between the remote terminal and the U2N relay can allocate the first local identifier of the remote terminal to the remote terminal or allocate the local identifier corresponding to the U2N relay to the U2N relay. The purpose is to use the local identifier when data is transmitted between the remote terminal and the U2N relay before the remote terminal establishes a connection with the network device, thereby reducing the header overhead of the SRAP PDU. Before establishing an end-to-end connection between the remote terminal and the U2N relay, any U2U relay or a specified U2U relay (referred to as the first U2U relay here, and there is no limitation on how to determine it specifically, for example, it can be a U2U relay connected to the remote terminal or a U2U relay connected to the U2N relay) between the remote terminal and the U2N relay may not allocate the first local identifier of the remote terminal to the remote terminal or allocate the local identifier corresponding to the U2N relay to the U2N relay. In this way, when data is transmitted between the remote terminal and the U2N relay before the remote terminal establishes a connection with the network device, the local can be used to carry the L2 address of the remote terminal and the L2 address of the U2N relay in the SRAP PDU.

[0513] Optionally, when the processor is used to allocate the first local identifier of the remote terminal to the remote terminal, it is further used to perform the following operations:

[0514] Send fourth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the fourth information includes the first local identifier corresponding to the remote terminal; and / or;

[0515] Send a fifth piece of information to a network device serving the remote terminal, where the fifth piece of information includes a first local identifier of the remote terminal.

[0516] In an embodiment of the present application, the first U2U relay assigns a first local identifier of the remote terminal to the remote terminal, and sends the first local identifier corresponding to the remote terminal to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, and / or sends the first local identifier corresponding to the remote terminal to a network device, so that all communication nodes involved in communication in a multi-hop U2N relay scenario can perform correct routing based on the information included in the SRAP PDU header.

[0517] Optionally, when the processor is used to assign a local identifier corresponding to the U2N relay, the processor is further used to perform the following operations:

[0518] Send a sixth piece of information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the sixth piece of information includes the local identifier corresponding to the U2N relay; and / or;

[0519] Send a seventh piece of information to a network device serving the remote terminal, where the seventh piece of information includes the local identifier corresponding to the U2N relay.

[0520] In an embodiment of the present application, the first U2U relay assigns a local identifier corresponding to the U2N relay to the U2N relay, and sends the local identifier corresponding to the U2N relay (i.e., the local identifier of the U2N relay) to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, and / or sends the local identifier corresponding to the U2N relay to a network device, so that in the data forwarding process, the received data can perform correct routing based on the information included in the SRAP PDU header.

[0521] Optionally, the processor is further used to perform the following operations:

[0522] Receive a second local identifier of the remote terminal from a network device, and use the second local identifier of the remote terminal in the SRAP PDU header.

[0523] In the embodiment of the present application, the first U2U relay may receive the second local identifier of the remote terminal from the network device and use the second local identifier of the remote terminal in the SRAP PDU header, so that in the data forwarding process, the node receiving the SRAP PDU can perform correct routing based on the information included in the SRAP PDU header.

[0524] Optionally, the fifth information and / or the seventh information are carried by Uu RRC signaling or MAC CE, and the fourth information and / or the sixth information are carried by PC5-RRC or sidelink MAC CE.

[0525] It should be noted here that the data transmission device in the multi-hop relay scenario provided by the present application can implement all the method steps implemented by the method embodiment described in the second aspect above, and can achieve the same technical effects. The same parts and beneficial effects as those in the method embodiment will not be specifically described in this embodiment.

[0526] Figure 12 FIG. 2 is a second schematic structural diagram of the data transmission device in the multi-hop relay scenario provided by the embodiment of the present application. As Figure 12 shown, the data transmission device in the multi-hop relay scenario provided by this embodiment is applied to the first terminal-to-terminal relay U2U relay. Then, the data transmission device 1200 in the multi-hop relay scenario provided by this embodiment includes:

[0527] A first processing unit 1201, configured to, for the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, not allocate the first local identifier of the remote terminal to the remote terminal or allocate the first local identifier of the remote terminal to the remote terminal; and / or

[0528] A second processing unit 1202, configured to, for the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, not allocate the local identifier corresponding to the U2N relay to the U2N relay or allocate the local identifier corresponding to the U2N relay to the U2N relay;

[0529] Wherein, the first U2U relay is any U2U relay or a specified U2U relay between the remote terminal and the U2N relay.

[0530] In an embodiment of the present application, before establishing an end-to-end connection between a remote terminal and a U2N relay, any U2U relay or a designated U2U relay (herein referred to as the first U2U relay, and there is no limitation on how to determine it specifically. For example, it can be a U2U relay connected to the remote terminal or a U2U relay connected to the U2N relay) between the remote terminal and the U2N relay can allocate a first local identifier of the remote terminal to the remote terminal or allocate a local identifier corresponding to the U2N relay to the U2N relay. The purpose is to use the local identifier when data is transmitted between the remote terminal and the U2N relay before the remote terminal establishes a connection with a network device, thereby reducing the header overhead of the SRAP PDU. Before establishing an end-to-end connection between the remote terminal and the U2N relay, any U2U relay or a designated U2U relay (herein referred to as the first U2U relay, and there is no limitation on how to determine it specifically. For example, it can be a U2U relay connected to the remote terminal or a U2U relay connected to the U2N relay) between the remote terminal and the U2N relay may not allocate a first local identifier of the remote terminal to the remote terminal or allocate a local identifier corresponding to the U2N relay to the U2N relay. In this way, when data is transmitted between the remote terminal and the U2N relay before the remote terminal establishes a connection with a network device, the local can be used to carry the L2 address of the remote terminal and the L2 address of the U2N relay in the SRAP PDU.

[0531] Optionally, the device further includes: a sending unit; the sending unit is configured to, in the case of allocating the first local identifier of the remote terminal to the remote terminal,

[0532] send fourth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the fourth information includes the first local identifier corresponding to the remote terminal; and / or;

[0533] send fifth information to a network device serving the remote terminal, where the fifth information includes the first local identifier of the remote terminal.

[0534] In the embodiments of the present application, the first U2U relay assigns a first local identifier of the remote terminal to the remote terminal, and sends the first local identifier corresponding to the remote terminal to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, and / or sends the first local identifier corresponding to the remote terminal to a network device, so that all communication nodes involved in communication in a multi-hop U2N relay scenario can perform correct routing based on the information included in the SRAP PDU header.

[0535] Optionally, the sending unit is further configured to: when assigning a local identifier corresponding to the U2N relay to the U2N relay,

[0536] send sixth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the sixth information includes the local identifier corresponding to the U2N relay; and / or;

[0537] send seventh information to a network device serving the remote terminal, where the seventh information includes the local identifier corresponding to the U2N relay.

[0538] In the embodiments of the present application, the first U2U relay assigns a local identifier corresponding to the U2N relay to the U2N relay, and sends the local identifier corresponding to the U2N relay (i.e., the local identifier of the U2N relay) to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, and / or sends the local identifier corresponding to the U2N relay to a network device, so that in the data forwarding process, the received data can perform correct routing based on the information included in the SRAP PDU header.

[0539] Optionally, the apparatus further includes: a receiving unit; the receiving unit is configured to:

[0540] receive a second local identifier of the remote terminal from a network device, and use the second local identifier of the remote terminal in the SRAP PDU header.

[0541] In the embodiments of the present application, the first U2U relay may receive the second local identifier of the remote terminal from a network device and use the second local identifier of the remote terminal in the SRAP PDU header, so that in the data forwarding process, the node receiving the SRAP PDU can perform correct routing based on the information included in the SRAP PDU header.

[0542] Optionally, the fifth information and / or the seventh information are carried by Uu RRC signaling or MAC CE, and the fourth information and / or the sixth information are carried by PC5-RRC or sidelink MAC CE.

[0543] It should be noted here that the data transmission device in the multi-hop relay scenario provided by this application can implement all the method steps implemented in the method embodiments described in the second aspect above, and can achieve the same technical effects. Therefore, the same parts and beneficial effects as those in the method embodiments will not be specifically described in this embodiment.

[0544] Figure 13 This is the third structural schematic diagram of the data transmission device in the multi-hop relay scenario provided by the embodiments of this application. As Figure 13 shown, if the data transmission device in the multi-hop relay scenario provided by this embodiment is applied to a network device, the data transmission device in the multi-hop relay scenario provided by this embodiment includes: a transceiver 1300, configured to receive and send data under the control of a processor 1310.

[0545] Among them, in Figure 13 , the bus architecture may include any number of interconnected buses and bridges, specifically, various circuits of one or more processors represented by the processor 1310 and a memory represented by the memory 1320 are linked together. The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art. Therefore, they will not be further described herein. The bus interface provides an interface. The transceiver 1300 may be multiple components, that is, including a transmitter and a receiver, and provides a unit for communicating with various other devices on a transmission medium, and these transmission mediums include wireless channels, wired channels, optical fiber cables, and other transmission mediums. The processor 1310 is responsible for managing the bus architecture and general processing, and the memory 1320 may store data used by the processor 1310 when performing operations.

[0546] The processor 1310 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a complex programmable logic device (CPLD), and the processor may also adopt a multi-core architecture.

[0547] In this embodiment, the memory 1320 is used to store computer programs; the transceiver 1300 is used to transmit and receive data under the control of the processor; the processor 1310 is used to read the computer programs in the memory and perform the following operations:

[0548] Send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the terminal-to-network relay U2N relay;

[0549] Send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N Relay, and any one U2U relay between the remote terminal and the U2N relay.

[0550] In the embodiment of the present application, the network device can implement data forwarding in a multi-hop relay scenario through the following multiple methods to ensure that data can be correctly routed to the target node: Method 1: Send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the U2N relay; Method 2: Send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N Relay, and any one U2U relay between the remote terminal and the U2N relay; Method 3: Combine Method 1 and Method 2.

[0551] Optionally, the processor 1310 is further configured to perform the following operation: In the uplink transmission direction, determine the corresponding Packet Data Convergence Protocol (PDCP) entity according to the second local identifier of the remote terminal carried in the SRAP PDU header.

[0552] In the embodiment of the present application, in the uplink transmission direction, the network device determines the corresponding Packet Data Convergence Protocol (PDCP) entity based on the second local identifier of the remote terminal carried in the SRAP PDU header, which is convenient for forwarding data to the appropriate PDCP entity, so as to ensure that the received SRAP data is delivered to the correct PDCP entity.

[0553] Optionally, the processor 1310 is further configured to perform at least one of the following operations:

[0554] Receive the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay sent by the U2N relay;

[0555] Receive the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay sent by any one of the U2U relays between the remote terminal and the U2N relay;

[0556] Receive the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay sent by the remote terminal.

[0557] In the embodiments of the present application, the network device may receive the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay sent by at least one of the U2N relay, any one of the U2U relays between the remote terminal and the U2N relay, and the remote terminal, so that in the data forwarding process, correct routing can be performed based on the information included in the SRAP PDU header.

[0558] Optionally, the processor 1310 is further configured to perform at least one of the following operations:

[0559] Receive the eighth information sent by the U2N relay, and allocate a corresponding first local identifier for the U2N relay according to the eighth information;

[0560] Send the ninth information to the U2N relay, where the ninth information is used to indicate the correspondence between the first local identifier allocated by the network device for the U2N relay and the local identifier corresponding to the U2N relay.

[0561] In the embodiments of the present application, the network device may receive the eighth information sent by the U2N relay for indicating that the network device allocates a corresponding first local identifier for the U2N relay. The network device allocates a corresponding first local identifier for the U2N relay (here refers to the newly allocated local identifier), and sends the first local identifier allocated for it and the local identifier corresponding to the U2N relay (here refers to the local identifier that the U2N relay already had / was previously allocated) to the U2N relay, so that correct routing can be performed based on the information included in the SRAP PDU header.

[0562] Optionally, the eighth information and / or the ninth information are carried by Uu interface RRC signaling or MAC CE.

[0563] Optionally, 1 bit of indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

[0564] In the embodiments of the present application, while enabling data to be correctly routed to the target node, the corresponding end-to-end scenario can be identified through the 1-bit indication information carried in the SRAP PDU header, such as: the terminal-to-network device scenario, or the terminal-to-terminal scenario, so as to perform appropriate processing on the SRAP PDU.

[0565] It should be noted here that the data transmission device in the multi-hop relay scenario provided by the present application can implement all the method steps implemented by the method embodiments described in the above third aspect, and can achieve the same technical effects. The same parts and beneficial effects as those in the method embodiments will not be specifically described in this embodiment.

[0566] Figure 14 FIG. 4 is a schematic structural diagram of a data transmission device in a multi-hop relay scenario provided by an embodiment of the present application. As Figure 14 shown, the data transmission device in the multi-hop relay scenario provided by this embodiment is applied to a network device. The data transmission device 1400 in the multi-hop relay scenario includes:

[0567] A first sending unit 1401, configured to send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the terminal-to-network relay U2N relay; and / or,

[0568] A second sending unit 1402, configured to send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N Relay, and any one U2U relay between the remote terminal and the U2N relay.

[0569] In the embodiments of the present application, the network device can forward data in the multi-hop relay scenario in the following multiple ways to ensure that the data can be correctly routed to the target node: Way 1: Send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the U2N relay; Way 2: Send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N Relay, and any one U2U relay between the remote terminal and the U2N relay; Way 3: Combine Way 1 and Way 2.

[0570] Optionally, the device further includes: a processing unit; the processing unit is configured to:

[0571] In the uplink transmission direction, determine the corresponding packet data convergence protocol (PDCP) entity according to the second local identifier of the remote terminal carried in the SRAP PDU header.

[0572] In an embodiment of the present application, in the uplink transmission direction, the network device determines a corresponding Packet Data Convergence Protocol (PDCP) entity based on the second local identifier of the remote terminal carried in the SRAP PDU header, facilitating the forwarding of data to the appropriate PDCP entity, so as to ensure that the received SRAP data is delivered to the correct PDCP entity.

[0573] Optionally, the device further includes a receiving unit; the receiving unit is configured to perform at least one of the following:

[0574] Receive the first local identifier of the remote terminal sent by the U2N relay and / or the local identifier corresponding to the U2N relay;

[0575] Receive the first local identifier of the remote terminal sent by any U2U relay between the remote terminal and the U2N relay and / or the local identifier corresponding to the U2N relay;

[0576] Receive the first local identifier of the remote terminal sent by the remote terminal and / or the local identifier corresponding to the U2N relay.

[0577] In an embodiment of the present application, the network device may receive the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay sent by at least one of the U2N relay, any U2U relay between the remote terminal and the U2N relay, and the remote terminal, so that in the data forwarding process, correct routing can be performed based on the information included in the SRAP PDU header.

[0578] Optionally, the processing unit is further configured to perform at least one of the following:

[0579] Receive the eighth information sent by the U2N relay, and allocate a corresponding first local identifier to the U2N relay according to the eighth information;

[0580] Send the ninth information to the U2N relay, where the ninth information is used to indicate the correspondence between the first local identifier allocated by the network device to the U2N relay and the local identifier corresponding to the U2N relay.

[0581] In an embodiment of the present application, a network device may receive eighth information sent by a U2N relay for instructing the network device to allocate a corresponding first local identifier to the U2N relay. The network device allocates a corresponding first local identifier to the U2N relay (herein referring to the newly allocated local identifier), and sends the allocated first local identifier and the local identifier corresponding to the U2N relay (herein referring to the local identifier that the U2N relay already had / was previously allocated) to the U2N relay, and can perform correct routing based on the information included in the SRAP PDU header.

[0582] Optionally, the eighth information and / or the ninth information is carried by Uu interface RRC signaling or MAC CE.

[0583] Optionally, 1 bit of indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

[0584] In an embodiment of the present application, while enabling the data to be correctly routed to the target node, the 1 bit of indication information carried in the SRAP PDU header can be used to identify the corresponding end-to-end scenario, such as: the terminal-to-network device scenario, or the terminal-to-terminal scenario, so as to perform appropriate processing on the SRAP PDU.

[0585] It should be noted here that the data transmission device in the multi-hop relay scenario provided by the present application can implement all the method steps implemented by the method embodiment described in the above third aspect, and can achieve the same technical effects. The same parts and beneficial effects as those in the method embodiment will not be specifically described in this embodiment.

[0586] It should be noted that the division of units in the embodiments of the present application is schematic, and is only a logical function division. In actual implementation, there may be other division methods. In addition, in each embodiment of the present application, the functional units may be integrated into a processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above integrated unit may be implemented in the form of hardware or in the form of a software functional unit.

[0587] When the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a processor-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to execute all or part of the steps of the methods described in various embodiments of this application.

[0588] Embodiments of this application also provide a non-transitory readable storage medium. The non-transitory readable storage medium stores a computer program, and the computer program is used to cause a processor to execute any one of the above method embodiments.

[0589] Among them, the non-transitory readable storage medium can be any available medium or data storage device accessible by a processor, including but not limited to magnetic memories (such as floppy disks, hard disks, magnetic tapes, magneto-optical discs (MO), etc.), optical memories (such as CDs, DVDs, BDs, HVDs, etc.), and semiconductor memories (such as ROMs, EPROMs, EEPROMs, non-volatile memories (NANDFLASH), solid state drives (SSD), etc.).

[0590] Those skilled in the art should understand that the embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, this application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories and optical memories, etc.) containing computer-usable program codes.

[0591] This application is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of this application. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer-executable instructions. These computer-executable instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the functions specified in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0592] These processor-executable instructions may also be stored in a processor-readable memory that can direct a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the processor-readable memory produce a manufacture including instruction means that implement the function specified in one process or a plurality of processes and / or boxes Figure 1 in one box or a plurality of boxes Figure 1 specified in one box or a plurality of boxes.

[0593] It will be apparent to those skilled in the art that various modifications and variations can be made to the present application without departing from the spirit and scope of the application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these modifications and variations.

Claims

1. A data transmission method in a multi-hop relay scenario, characterized in that, applied to the terminal-to-network relay U2Nrelay, the method includes: After receiving data from the previous hop node, perform any one of the following operations: Perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol SRAP layer; Carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit PDU header; Use the second local identifier of the remote terminal in the SRAP PDU header; Use the first local identifier of the remote terminal in the SRAP PDU header; Wherein, in the uplink transmission direction, the previous hop node is the terminal-to-terminal relay U2U relay; in the downlink transmission direction, the previous hop node is a network device; the first local identifier of the remote terminal is the local identifier assigned to the remote terminal by the first U2U relay between the remote terminal and the U2N relay, and the first U2U relay is any one of the U2U relays between the remote terminal and the U2N relay or a specified U2U relay; the second local identifier of the remote terminal is the local identifier assigned to the remote terminal by the network device.

2. The method according to claim 1, characterized in that, The replacement of the first local identifier of the remote terminal and the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol SRAP layer includes at least one of the following: In the uplink transmission direction, for the received SRAP PDU, replace the first local identifier of the remote terminal included in the SRAP PDU header with the second local identifier of the remote terminal; In the downlink transmission direction, for the received SRAP PDU, replace the second local identifier of the remote terminal included in the SRAP PDU header with the first local identifier of the remote terminal.

3. The method according to claim 1, characterized in that, The method further includes: In the uplink transmission direction, for the received SRAP PDU, delete the local identifier of the U2N relay included in the SRAP PDU header; In the downlink transmission direction, for the received SRAP PDU, add the local identifier of the U2N relay to the SRAP PDU header; Wherein, the local identifier of the U2N relay is the local identifier assigned to the U2N relay by any one of the U2U relays between the remote terminal and the U2N relay.

4. The method according to claim 1, characterized in that, The SRAP PDU header carries 1 bit of indication information, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

5. The method according to claim 1, characterized in that, Carrying the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit (PDU) header at the same time includes: Generating a new SRAP PDU according to the received SRAP PDU, and carrying the first local identifier of the remote terminal and the second local identifier of the remote terminal in the PDU header of the new SRAP PDU at the same time.

6. The method according to claim 1, wherein, the method further includes at least one of the following: notifying the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using first information; notifying any one U2U relay between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using second information; notifying the remote terminal of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using third information.

7. The method according to claim 6, wherein, the first information is carried by radio resource control (RRC) signaling or media access control unit (MAC) CE through the Uu interface; the second information and / or the third information are carried by direct communication interface PC5-RRC signaling or sidelink MAC CE.

8. A data transmission method in a multi-hop relay scenario, wherein, applied to a first terminal-to-terminal relay U2U relay, the method includes: for a remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, not allocating the first local identifier of the remote terminal to the remote terminal or allocating the first local identifier of the remote terminal to the remote terminal; and / or, for the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, not allocating the local identifier corresponding to the U2N relay to the U2N relay or allocating the local identifier corresponding to the U2N relay to the U2N relay; wherein, the first U2U relay is any one U2U relay or a specified U2U relay between the remote terminal and the U2N relay.

9. The method according to claim 8, wherein, if the first local identifier of the remote terminal is allocated to the remote terminal, the method further includes: sending fourth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the fourth information includes the first local identifier corresponding to the remote terminal; and / or; sending fifth information to the network device serving the remote terminal, where the fifth information includes the first local identifier of the remote terminal.

10. The method according to claim 8, wherein, If a local identifier corresponding to the U2N relay is allocated for the U2N relay, the method includes: Sending sixth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the sixth information includes the local identifier corresponding to the U2N relay; and / or; Sending seventh information to a network device serving the remote terminal, where the seventh information includes the local identifier corresponding to the U2N relay.

11. The method according to claim 8, wherein, the method further includes: Receiving a second local identifier of the remote terminal from a network device and using the second local identifier of the remote terminal in the SRAP PDU header.

12. The method according to claim 9 or 10, wherein, The fifth information and / or the seventh information is carried by Uu RRC signaling or MAC CE, and the fourth information and / or the sixth information is carried by PC5-RRC or sidelink MAC CE.

13. A data transmission method in a multi-hop relay scenario, wherein, Applied to a network device, the method includes at least one of the following: Sending an SRAP PDU carrying both a first local identifier of a remote terminal and a second local identifier of the remote terminal to a terminal-to-network relay U2N relay; Sending the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N relay, and any one U2U relay between the remote terminal and the U2N relay.

14. The method according to claim 13, wherein, the method further includes: In an uplink transmission direction, determining a corresponding packet data convergence protocol (PDCP) entity according to the second local identifier of the remote terminal carried in the SRAP PDU header.

15. The method according to claim 13, wherein, the method further includes at least one of the following: Receiving the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay sent by the U2N relay; Receiving the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay sent by any one U2U relay between the remote terminal and the U2N relay; Receiving the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay sent by the remote terminal.

16. The method according to claim 13, wherein, the method further includes at least one of the following: Receiving eighth information sent by the U2N relay and allocating a corresponding first local identifier for the U2N relay according to the eighth information; Send a ninth piece of information to the U2N relay, where the ninth piece of information is used to indicate the correspondence between the first local identifier assigned by the network device to the U2N relay and the local identifier corresponding to the U2N relay.

17. The method according to claim 16, wherein, the eighth piece of information and / or the ninth piece of information is carried by Uu interface RRC signaling or MAC CE.

18. The method according to claim 14, wherein, a 1-bit indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

19. A data transmission device in a multi-hop relay scenario, wherein, the device is applied to a terminal-to-network relay U2N relay, and the device includes: a processing unit, configured to, after receiving data from the previous hop node, perform at least one of the following operations: perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol SRAP layer; carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit PDU header; use the second local identifier of the remote terminal in the SRAP PDU header; use the first local identifier of the remote terminal in the SRAP PDU header; wherein, in the uplink transmission direction, the previous hop node is a terminal-to-terminal relay U2U relay; in the downlink transmission direction, the previous hop node is a network device; the first local identifier of the remote terminal is the local identifier assigned to the remote terminal by the first U2U relay between the remote terminal and the U2N relay, the first U2U relay is any U2U relay or a specified U2U relay between the remote terminal and the U2N relay, and the second local identifier of the remote terminal is the local identifier assigned to the remote terminal by the network device.

20. A data transmission device in a multi-hop relay scenario, wherein, applied to a first terminal-to-terminal relay U2U relay, the device includes: a first processing unit, configured to, for a remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, not assign the first local identifier of the remote terminal to the remote terminal or assign the first local identifier of the remote terminal to the remote terminal; and / or, a second processing unit, configured to, for the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, not assign the local identifier corresponding to the U2N relay to the U2N relay or assign the local identifier corresponding to the U2N relay to the U2N relay; Among them, the first U2U relay is any U2U relay or a designated U2U relay between the remote terminal and the U2N relay.

21. A data transmission device in a multi-hop relay scenario, characterized in that it is applied to a network device, and the device includes: A first sending unit, configured to send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the terminal-to-network relay U2N relay; and / or, A second sending unit, configured to send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N relay, and any U2U relay between the remote terminal and the U2N relay.

22. A data transmission device in a multi-hop relay scenario, characterized in that the device is applied to the terminal-to-network relay U2N relay, and the device includes a memory, a transceiver, and a processor: The memory is used to store a computer program; the transceiver is used to send and receive data under the control of the processor; the processor is used to read the computer program in the memory and perform the following operations: After receiving data from the previous hop node, perform at least one of the following operations: Perform replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol SRAP layer; Carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit PDU header; Use the second local identifier of the remote terminal in the SRAP PDU header; Use the first local identifier of the remote terminal in the SRAP PDU header; Among them, in the uplink transmission direction, the previous hop node is the terminal-to-terminal relay U2U relay; in the downlink transmission direction, the previous hop node is a network device; the first local identifier of the remote terminal is a local identifier assigned to the remote terminal by the first U2U relay between the remote terminal and the U2N relay, and the first U2U relay is any U2U relay or a designated U2U relay between the remote terminal and the U2N relay, and the second local identifier of the remote terminal is a local identifier assigned to the remote terminal by the network device.

23. The device according to claim 22, characterized in that when the processor performs replacement between the first local identifier of the remote terminal and the second local identifier of the remote terminal at the direct communication interface link relay adaptation protocol SRAP layer, it specifically includes at least one of the following: In the uplink transmission direction, for the received SRAP PDU, replace the first local identifier of the remote terminal included in the SRAP PDU header with the second local identifier of the remote terminal; In the downlink transmission direction, for the received SRAP PDU, replace the second local identifier of the remote terminal included in the SRAP PDU header with the first local identifier of the remote terminal.

24. The apparatus according to claim 22, wherein, the processor is further configured to perform the following operations: In the uplink transmission direction, for the received SRAP PDU, delete the local identifier of the U2N relay included in the SRAP PDU header; In the downlink transmission direction, for the received SRAP PDU, add the local identifier of the U2N relay to the SRAP PDU header; wherein the local identifier of the U2N relay is a local identifier assigned to the U2N relay by any one of the U2U relays between the remote terminal and the U2N relay.

25. The apparatus according to claim 22, wherein, 1 bit of indication information is carried in the SRAP PDU header, and the indication information is used to indicate whether the data carried in the SRAP PDU is U2N data or U2U data.

26. The apparatus according to claim 22, wherein, when the processor is configured to carry both the first local identifier of the remote terminal and the second local identifier of the remote terminal in the SRAP protocol data unit PDU header, specifically includes: Generate a new SRAP PDU according to the received SRAP PDU, and both the first local identifier of the remote terminal and the second local identifier of the remote terminal are carried in the PDU header of the new SRAP PDU.

27. The apparatus according to claim 22, wherein, the processor is further configured to perform at least one of the following: Notify the network device of the first local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the first information; Notify any one of the U2U relays between the remote terminal and the U2N relay of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the second information; Notify the remote terminal of the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay by using the third information.

28. A data transmission apparatus in a multi-hop relay scenario, wherein, applied to the first terminal-to-terminal relay U2U relay, the apparatus includes: a memory, a transceiver, and a processor: The memory is used to store computer programs; the transceiver is used to transmit and receive data under the control of the processor; the processor is used to read the computer programs in the memory and perform the following operations: For the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, do not assign the first local identifier of the remote terminal to the remote terminal or assign the first local identifier of the remote terminal to the remote terminal; and / or, For the remote terminal, before establishing an end-to-end connection between the remote terminal and the U2N relay, do not allocate the local identifier corresponding to the U2N relay to the U2N relay or allocate the local identifier corresponding to the U2N relay to the U2N relay; Wherein, the first U2U relay is any U2U relay or a designated U2U relay between the remote terminal and the U2N relay.

29. The apparatus according to claim 28, wherein, when the processor is used to allocate the first local identifier of the remote terminal to the remote terminal, the processor is further used to perform the following operations: send fourth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the fourth information includes the first local identifier corresponding to the remote terminal; and / or; send fifth information to the network device serving the remote terminal, where the fifth information includes the first local identifier of the remote terminal.

30. The apparatus according to claim 28, wherein, when the processor is used to allocate the local identifier corresponding to the U2N relay to the U2N relay, the processor is further used to perform the following operations: send sixth information to the remote terminal, the U2N relay, and other U2U relays between the remote terminal and the U2N relay, where the sixth information includes the local identifier corresponding to the U2N relay; and / or; send seventh information to the network device serving the remote terminal, where the seventh information includes the local identifier corresponding to the U2N relay.

31. The apparatus according to claim 28, wherein, the processor is further used to perform the following operations: receive the second local identifier of the remote terminal from the network device and use the second local identifier of the remote terminal in the SRAP PDU header.

32. A data transmission apparatus in a multi-hop relay scenario, wherein, applied to a network device, the apparatus includes: a memory, a transceiver, a processor: The memory is used to store a computer program; the transceiver is used to transmit and receive data under the control of the processor; the processor is used to read the computer program in the memory and perform at least one of the following operations: send an SRAP PDU carrying both the first local identifier of the remote terminal and the second local identifier of the remote terminal to the terminal-to-network relay U2N relay; send the second local identifier of the remote terminal and / or the local identifier corresponding to the U2N relay to at least one of the remote terminal, the U2N Relay, and any one of the U2U relays between the remote terminal and the U2N relay.

33. The apparatus according to claim 32, wherein, The processor is further configured to perform the following operations: in the uplink transmission direction, determine a corresponding Packet Data Convergence Protocol (PDCP) entity according to the second local identifier of the remote terminal carried in the SRAP PDU header.

34. The apparatus according to claim 32, wherein, the processor is further configured to perform at least one of the following operations: receive the first local identifier of the remote terminal sent by the U2N relay and / or the local identifier corresponding to the U2N relay; receive the first local identifier of the remote terminal sent by any U2U relay between the remote terminal and the U2N relay and / or the local identifier corresponding to the U2N relay; receive the first local identifier of the remote terminal sent by the remote terminal and / or the local identifier corresponding to the U2N relay.

35. The apparatus according to claim 32, wherein, the processor is further configured to perform at least one of the following operations: receive the eighth information sent by the U2N relay, and allocate a corresponding first local identifier for the U2N relay according to the eighth information; send the ninth information to the U2N relay, where the ninth information is used to indicate the correspondence between the first local identifier allocated by the network device for the U2N relay and the local identifier corresponding to the U2N relay.

36. A non-transitory readable storage medium, wherein, the non-transitory readable storage medium stores a computer program, and the computer program is used to cause the processor to execute the method according to any one of claims 1 to 18.

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