CN110958642B

CN110958642B - Data transmission method and device for wireless backhaul network

Info

Publication number: CN110958642B
Application number: CN201811134516.XA
Authority: CN
Inventors: 朱元萍; 戴明增; 刘菁
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2018-09-27
Filing date: 2018-09-27
Publication date: 2022-04-22
Anticipated expiration: 2038-09-27
Also published as: CN110958642A; WO2020063504A1

Abstract

The application provides a data transmission method and device for a wireless backhaul network, which can perform data transmission in the wireless backhaul network. The method comprises the following steps: a sending node generates a first data packet and sends the first data packet to a receiving node; the receiving node receives the first data packet and analyzes the first data packet; the first data packet includes a first PDCP PDU generated by a first PDCP entity, the first PDCP PDU includes a first header and a first payload, the first header includes identification information of a PDCP layer of the first PDCP PDU, the first payload includes identification information of a first protocol layer of the first payload, and the first data packet further includes indication information of the first PDCP PDU, the indication information indicating that the first payload in the first PDCP PDU is data of the first protocol layer.

Description

Data transmission method and device for wireless backhaul network

Technical Field

The present application relates to the field of communications, and in particular, to a method and an apparatus for data transmission in a wireless backhaul network in the field of communications.

Background

In an Integrated Access and Backhaul (IAB) network, a wireless backhaul node, which may also be referred to as an IAB node or a Relay Node (RN), may provide wireless access services to a terminal device. The traffic data of the terminal device may be transmitted by the wireless backhaul node connected to a donor node, such as an IAB donor (IAB donor) or a donor base station (donor gbdeb, DgNB), via a wireless backhaul link. IAB networks support multi-hop and multi-connection networking, and therefore, multiple transmission paths may exist between the terminal device and the host node. On one transmission path, there is a certain hierarchical relationship between the wireless backhaul nodes, and between the wireless backhaul nodes and the host node serving the wireless backhaul nodes, and each wireless backhaul node regards the node providing backhaul service as a parent node (also referred to as the next hop node of the wireless backhaul node on the uplink in the present application), and accordingly, each wireless backhaul node can be regarded as a child node of its parent node.

The wireless backhaul node may have the role of a Mobile Terminal (MT), in other words, the wireless backhaul node may include at least one MT unit, for example, the wireless backhaul node may include the role of only one MT, which is a multi-connection capable MT, and the wireless backhaul node may establish backhaul connections with multiple parent nodes of the wireless backhaul node through the MT; also for example, the wireless backhaul node may include a plurality of MTs, each MT of the plurality of MTs establishing a connection with a parent node of the wireless backhaul node as an independent backhaul link of the wireless backhaul node.

Because the MT unit includes Packet Data Convergence Protocol (PDCP) layer, adaptation layer, Radio Link Control (RLC) layer, Medium Access Control (MAC) layer, and Physical (PHY) layer, when the wireless backhaul node has the MT role, how to perform data transmission in the IAB network becomes a technical problem to be solved urgently.

Disclosure of Invention

The application provides a data transmission method and device for a wireless backhaul network, which can perform data transmission in an IAB network.

In a first aspect, a data transmission method for a wireless backhaul network is provided, including: a sending node generates a first data packet; the sending node sends the first data packet to a receiving node; the first data packet comprises a first PDCP Protocol Data Unit (PDU) generated by a first PDCP entity, the first PDCP PDU comprises a first packet header and a first load, the first packet header comprises identification information of a PDCP layer of the first PDCP PDU, the first load comprises identification information of a first protocol layer of the first load, the first data packet further comprises indication information of the first PDCP PDU, the indication information is used for indicating that the first load in the first PDCP PDU is data of the first protocol layer, the first protocol layer corresponds to at least one PDCP entity in the sending node, and the at least one PDCP entity comprises the first PDCP entity.

The data transmission method for the wireless backhaul network of the embodiment of the present application, transmits a first data packet including a first PDCP PDU through a transmitting node, the first PDCP PDU includes identification information of a PDCP layer of the first PDCP PDU and identification information of a first protocol layer of the first payload, carrying indication information of a first PDCP PDU in a first data packet, for indicating that a first payload in the first PDCP PDU is data of a first protocol layer, so that the receiving node transmits the first payload in the first data packet to the first protocol layer of the receiving node according to the indication information, and processes the first payload in the first PDCP PDU according to the identification information of the PDCP layer of the first PDCP PDU and the identification information of the first protocol layer of the first payload, therefore, data transmission in the wireless backhaul network is completed, the sending node and the receiving node are ensured to be consistent in understanding, and errors are not easy to occur.

The identification information of the PDCP layer of the first PDCP PDU may be a Sequence Number (SN) or time information of the first PDCP PDU in the PDCP layer (e.g., a generation time or a latest failure time of the first PDCP PDU in the PDCP layer), and the like, and the identification information of the first protocol layer of the first payload may be a SN or time information of the first PDCP PDU in the first protocol layer (e.g., a generation time or a latest failure time of the first PDCP PDU in the first protocol layer), which is not limited in this embodiment of the application.

The indication information of the first PDCP PDU is used to indicate that the first payload in the first PDCP PDU is data of the first protocol layer, and the indication information may be generated in the first protocol layer or the PDCP layer, which is not limited in this embodiment of the present invention. The indication information may be one or more bit values, for example, a value of 1 in the indication information indicates that the first payload in the first PDCP PDU is data of the first protocol layer, which is not limited in this embodiment of the present application.

It should be understood that the first protocol layer may be an F1application protocol (F1application protocol, F1AP) protocol layer, or may be an additional layer between the F1AP layer and the PDCP layer, which is not limited in this embodiment of the present application. The F1AP layer is located above the PDCP layer, and the transmitting node and the receiving node each have a first protocol layer and a PDCP layer.

With reference to the first aspect, in certain implementations of the first aspect, the at least one PDCP entity corresponds to at least one mobile terminal, MT, unit one to one, respectively; or, the number of the at least one PDCP entity is multiple, and multiple PDCP entities of the at least one PDCP entity correspond to one MT unit of the at least one MT unit.

For example, the at least one PDCP entity may correspond to at least one MT unit, and the at least one PDCP entity and the at least one MT unit may be in a one-to-one correspondence relationship, or a plurality of PDCP entities correspond to one MT unit, which is not limited in this embodiment of the present application. Illustratively, when the sending node is a wireless backhaul node, the at least one PDCP entity belongs to at least one MT unit, and when the sending node is a host node, the at least one PDCP entity and the at least one MT unit at the wireless backhaul node have a corresponding relationship due to the absence of the MT unit in the host node.

Optionally, the wireless backhaul node includes a plurality of MT units, and the first data packet may further carry an identifier of the wireless backhaul node (e.g., an identifier of an MT unit of the wireless backhaul node, or an identifier of a DU of the wireless backhaul node) and a bearer identifier (e.g., an ID of a bearer) corresponding to the MT unit. In this way, the receiving node can deliver the received first PDCP PDU to the corresponding PDCP entity according to the identification therein.

With reference to the first aspect, in certain implementations of the first aspect, the sending node has multiple next-hop nodes, and the sending node sends the first data packet to a receiving node, including: the sending node sends the first data packet to the receiving node through a first next hop node in the plurality of next hop nodes; the method further comprises the following steps: the sending node sends a second data packet to the receiving node through a second next hop node of the plurality of next hop nodes, wherein the second data packet includes a second PDCP PDU generated by a second PDCP entity of the at least one PDCP entity, the second PDCP PDU includes a second header and the first payload, the second header includes identification information of a PDCP layer of the second PDCP PDU, the second data packet further includes indication information of the second PDCP PDU, and the indication information of the second PDCP PDU is used to indicate that the first payload of the second PDCP PDU is data of the first protocol layer.

Illustratively, the sending node may have multiple next hop nodes, i.e., there are multiple transmission paths from the sending node to the receiving node. In this case, the sending node may have a data copying capability, and copy the first payload in the first packet into multiple copies to be sent on different paths respectively. The transmitting node may transmit a first packet including a first payload through a first next-hop node of the plurality of next-hop nodes while transmitting a first packet including the first payload through a second next-hop node of the plurality of next-hop nodes.

It should be understood that, during data transmission, a data packet sent by a sending node may be lost due to poor link quality and the like, whereas in the data transmission method for the wireless backhaul network according to the embodiment of the present application, the sending node has a capability of data packet replication, and the sending node may transmit a plurality of identical first payloads through different transmission paths, so that reliability of data transmission of the first protocol layer can be improved.

With reference to the first aspect, in certain implementations of the first aspect, the sending node is a wireless backhaul node, and the receiving node is a host node; or, the sending node is a host node, and the receiving node is a wireless backhaul node.

For uplink transmission, the sending node is a wireless backhaul node, the receiving node is a host node, and the first data packet transmitted may be a data packet that is from a terminal device and needs to be sent to the host node. For downlink transmission, the sending node is a host node, the receiving node is a wireless backhaul node, and the first data packet transmitted may be a data packet that comes from the host node and needs to be sent to the terminal device.

Optionally, when the host node is in a CU-DU separated form, the sending node or the receiving node may also be a centralized unit CU of the host node, and when the host CU is in a User Plane (UP) and Control Plane (CP) separated form, the sending node or the receiving node may also be a CU-CP, which is not limited in this embodiment of the present invention.

In a second aspect, another data transmission method for a wireless backhaul network is provided, including: a receiving node receives a first data packet from a sending node; the receiving node analyzes the first data packet; the first data packet comprises a first PDCP Protocol Data Unit (PDU) generated by a first PDCP entity, the first PDCP PDU comprises a first packet header and a first load, the first packet header comprises identification information of a PDCP layer of the first PDCP PDU, the first load comprises identification information of the first protocol layer of the first load, the first data packet further comprises indication information of the first PDCP PDU, the indication information of the first PDCP PDU is used for indicating that the first load in the first PDCP PDU is data of the first protocol layer, the first protocol layer corresponds to at least one PDCP entity in the sending node, and the at least one PDCP entity comprises the first PDCP entity.

With reference to the second aspect, in some implementations of the second aspect, the at least one PDCP entity corresponds to the at least one mobile terminal, MT, unit one to one; or, the number of the at least one PDCP entity is multiple, and multiple PDCP entities of the at least one PDCP entity correspond to one MT unit of the at least one MT unit.

With reference to the second aspect, in some implementations of the second aspect, the receiving node includes a plurality of previous-hop nodes, and the receiving node receives the first packet from the sending node, including: the receiving node receiving the first data packet from the transmitting node through a first previous-hop node of the plurality of previous-hop nodes; the method further comprises the following steps: the receiving node receives a second data packet from the transmitting node through a second previous hop node of the plurality of previous hop nodes, wherein the second data packet comprises a second PDCP PDU generated by a second PDCP entity of the at least one PDCP entity, the second PDCP PDU comprises a second header and a second payload, the second header comprises identification information of a PDCP layer of the second PDCP PDU, the second payload comprises identification information of a first protocol layer of the second payload, the second data packet further comprises indication information of the second PDCP PDU, and the indication information of the second PDCP PDU is used for indicating that the second payload of the second PDCP PDU is data of the first protocol layer; the receiving node parses the second packet.

In the data transmission method for the wireless backhaul network according to the embodiment of the present application, a plurality of transmission paths exist between the sending node and the receiving node, so that the sending node can send a plurality of data packets through different paths, and the receiving node can receive the plurality of data packets through corresponding paths and process the plurality of data packets.

With reference to the second aspect, in certain implementations of the second aspect, the method further includes: the receiving node acquires identification information of a first protocol layer of the first load and identification information of a first protocol layer of the second load; and the receiving node processes the first load and the second load in sequence according to the identification information of the first protocol layer of the first load and the identification information of the first protocol layer of the second load.

Optionally, the above-mentioned receiving node may sequence the multiple payloads in the multiple PDCP PDUs in the first protocol layer of the receiving node, but the embodiment of the present application does not limit this.

With reference to the second aspect, in certain implementations of the second aspect, the sequentially processing the first payload and the second payload includes: the receiving node detects whether the identification information of the first protocol layer of the first load is the same as the identification information of the first protocol layer of the second load; if the identification information of the first protocol layer of the first payload is the same as the identification information of the first protocol layer of the second payload, the receiving node processes the first payload or the second payload.

According to the method, in order to improve the reliability of data transmission, a sending node is allowed to transmit a plurality of data packets with the same load through different transmission paths, but if a receiving node receives a plurality of data packets with the same load, only the load of one data packet needs to be processed, so that the receiving node has the capability of repeated detection, the receiving node can be prevented from repeatedly processing the same load, and the data processing efficiency is improved.

With reference to the second aspect, in some implementations of the second aspect, the sending node is a wireless backhaul node, and the receiving node is a host node; or, the sending node is a host node, and the receiving node is a wireless backhaul node.

In a third aspect, another data transmission method for a wireless backhaul network is provided, including: the host node sends a first message to the wireless backhaul node, wherein the first message carries an identifier of at least one PDCP entity of the wireless backhaul node, and the identifier of the at least one PDCP entity is used for the F1application protocol F1AP layer of the wireless backhaul node to correspond to the at least one PDCP entity; the host node receives a second message from the wireless backhaul node, the second message indicating a configuration result of the wireless backhaul node for the first message.

Illustratively, the first message is used for configuring that there is a correspondence between the F1AP layer of the wireless backhaul node and at least one PDCP entity of the wireless backhaul node.

In the data transmission method for the wireless backhaul network according to the embodiment of the present application, the host node sends the first message to the wireless backhaul node to configure that there is a correspondence between the F1AP layer of the wireless backhaul node and at least one PDCP entity, and sends the second message to feed back the configuration result to the host node, so that the protocol layer architectures of the host node and the wireless backhaul node are consistent, and subsequent data transmission is performed between the wireless backhaul node and the host node.

With reference to the third aspect, in certain implementations of the third aspect, the first message is further used to instruct, by one of the at least one PDCP entity, to preferentially transmit data of the F1AP layer; or, the method further comprises: the host node sends a third message to the wireless backhaul node, the third message indicating that data of the F1AP layer is preferentially transmitted by one of the at least one PDCP entity.

Illustratively, a certain PDCP entity of the at least one configured PDCP entity may be indicated in the first message as a preferred PDCP entity, i.e., data of the F1AP layer is transmitted preferentially through the preferred PDCP entity. The data here refers to control plane data of the F1AP layer, and may specifically be signaling of the control plane. The host node may also configure the preferred PDCP entity for the wireless backhaul node through the third message, which is not limited in this embodiment.

With reference to the third aspect, in certain implementations of the third aspect, the first message and the second message are F1AP messages; or, the first message and the second message are Radio Resource Control (RRC) messages.

In a fourth aspect, another data transmission method for a wireless backhaul network is provided, including: the wireless backhaul node receiving a first message from a host node, the first message carrying an identification of at least one PDCP entity of the wireless backhaul node, the identification of the at least one PDCP entity being used for a F1application protocol F1AP layer of the wireless backhaul node to correspond to the at least one PDCP entity; and the wireless backhaul node configures according to the first message, and sends a second message to the host node, where the second message is used to indicate a configuration result of the wireless backhaul node on the first message.

With reference to the fourth aspect, in some implementations of the fourth aspect, the first message is further used to instruct one of the at least one PDCP entity to preferentially transmit data of the F1AP layer; or, the method further comprises: the wireless backhaul node receives a third message sent by the host node, where the third message is used to instruct one of the at least one PDCP entity to preferentially transmit data of the F1AP layer.

With reference to the fourth aspect, in certain implementations of the fourth aspect, the first message and the second message are F1AP messages; or, the first message and the second message are Radio Resource Control (RRC) messages.

In a fifth aspect, another data transmission method for a wireless backhaul network is provided, including: the host node sends a fourth message to the wireless backhaul node, wherein the fourth message carries an identifier of at least one adaptation layer entity of the wireless backhaul node, and the identifier of the at least one adaptation layer entity is used for enabling a Packet Data Convergence Protocol (PDCP) entity of the wireless backhaul node to correspond to the at least one adaptation layer entity; the host node receives a fifth message from the wireless backhaul node, the fifth message indicating a configuration result of the wireless backhaul node for the first message.

Exemplarily, the fourth message is used for configuring a correspondence relationship between a PDCP entity of the wireless backhaul node and at least one adaptation layer entity of the wireless backhaul node.

In the data transmission method for the wireless backhaul network according to the embodiment of the present application, the host node sends the fourth message to the wireless backhaul node to configure a correspondence relationship between the PDCP entity of the wireless backhaul node and at least one adaptation layer entity, and sends the fifth message to feed back the configuration result to the host node, so that protocol layer architectures of the host node and the wireless backhaul node are consistent, and subsequent data transmission is performed between the wireless backhaul node and the host node.

With reference to the fifth aspect, in some implementations of the fifth aspect, the fourth message is further used to indicate that data of the PDCP layer is preferentially transmitted by one of the at least one adaptation layer entity; the method further comprises the following steps: the host node sends a sixth message to the wireless backhaul node, where the sixth message is used to instruct one of the at least one adaptation layer entity to preferentially transmit data of the PDCP layer.

For example, in the above fourth message, it may be indicated that a certain adaptation layer entity of the configured at least one adaptation layer entity is a preferred adaptation layer entity, that is, data is preferentially transmitted through the adaptation layer entity. The data herein refers to control plane data, and may specifically be signaling of the control plane. The host node may also configure a preferred adaptation layer entity for the wireless backhaul node through a sixth message, which is not limited in this embodiment of the present application.

With reference to the fifth aspect, in certain implementations of the fifth aspect, the fourth message and the fifth message are F1AP messages; or, the fourth message and the fifth message are Radio Resource Control (RRC) messages.

In a sixth aspect, another data transmission method for a wireless backhaul network is provided, including: the wireless backhaul node receives a fourth message from a host node, where the fourth message carries an identifier of at least one adaptation layer entity of the wireless backhaul node, and the identifier of the at least one adaptation layer entity is used for a Packet Data Convergence Protocol (PDCP) entity of the wireless backhaul node to correspond to the at least one adaptation layer entity; and the wireless backhaul node performs configuration according to the fourth message, and sends a fifth message to the host node, where the fifth message is used to indicate a configuration result of the wireless backhaul node on the fourth message.

With reference to the sixth aspect, in some implementations of the sixth aspect, the fourth message is further used to instruct preferential transmission of data of the PDCP layer by one of the at least one adaptation layer entity; or, the method further comprises: and the wireless backhaul node receives a sixth message sent by the host node, where the sixth message is used to instruct one of the at least one adaptation layer entity to preferentially transmit data of the PDCP layer.

With reference to the sixth aspect, in certain implementations of the sixth aspect, the fourth message and the fifth message are F1AP messages; or, the fourth message and the fifth message are Radio Resource Control (RRC) messages.

In a seventh aspect, a data transmission apparatus for a wireless backhaul network is provided, configured to perform the method in any possible implementation manner of any one of the above aspects. The apparatus illustratively comprises means for performing the method of any one of the possible implementations of any one of the aspects set forth above.

In an eighth aspect, another data transmission apparatus for a wireless backhaul network is provided, the apparatus comprising: a transceiver, a memory, and a processor. Wherein the transceiver, the memory, and the processor communicate with each other through an internal connection path, the memory is configured to store instructions, the processor is configured to execute the instructions stored by the memory to control the receiver to receive signals and control the transmitter to transmit signals, and the processor is configured to execute the instructions stored by the memory to cause the processor to perform the method of any one of the possible implementations of any one of the aspects.

In a ninth aspect, there is provided a computer program product, the computer program product comprising: computer program code which, when run by a computer, causes the computer to perform the method of the above aspects.

In a tenth aspect, a computer-readable medium is provided for storing a computer program comprising instructions for performing the method in the above aspects.

In an eleventh aspect, there is provided a chip comprising a processor for calling up and executing instructions stored in a memory from the memory, so that a communication device in which the chip is installed performs the method in the above aspects.

In a twelfth aspect, another chip is provided, including: the system comprises an input interface, an output interface, a processor and a memory, wherein the input interface, the output interface, the processor and the memory are connected through an internal connection path, the processor is used for executing codes in the memory, and when the codes are executed, the processor is used for executing the method in the aspects.

Drawings

Fig. 1 shows a schematic diagram of a communication system of an embodiment of the present application.

Fig. 2 shows a schematic flow diagram of a data transmission method for a wireless backhaul network according to an embodiment of the present application.

Fig. 3 shows a schematic flow chart of another data transmission method for a wireless backhaul network according to an embodiment of the present application.

Fig. 4 shows a schematic flow chart of another data transmission method for a wireless backhaul network according to an embodiment of the present application.

Fig. 5 shows a schematic diagram of multiple connections of a multi-MT based wireless backhaul network according to an embodiment of the present application.

Fig. 6 shows a schematic diagram of a multi-MT based control plane protocol stack according to an embodiment of the present application.

Fig. 7 shows a schematic diagram of another control plane protocol stack based on multiple MTs according to an embodiment of the present application.

Fig. 8 shows a schematic diagram of a multi-MT based user plane protocol stack according to an embodiment of the present application.

Fig. 9 shows a schematic diagram of another user plane protocol stack based on multiple MTs according to an embodiment of the present application.

Fig. 10 illustrates a schematic diagram of a single MT based wireless backhaul network multi-connectivity according to an embodiment of the present application.

Fig. 11 shows a schematic diagram of a control plane protocol stack based on a single MT according to an embodiment of the present application.

Fig. 12 shows a schematic diagram of another control plane protocol stack based on a single MT according to an embodiment of the present application.

Fig. 13 shows a schematic block diagram of a data transmission apparatus for a wireless backhaul network according to an embodiment of the present application.

Fig. 14 shows a schematic block diagram of another data transmission apparatus for a wireless backhaul network according to an embodiment of the present application.

Detailed Description

The technical solution in the present application will be described below with reference to the accompanying drawings.

It should be understood that the names of all nodes and messages in the present application are only names set for convenience of description in the present application, and the names in the actual network may be different, and it should not be understood that the present application defines the names of various nodes and messages, on the contrary, any name having the same or similar function as the node or message used in the present application is considered as a method or equivalent replacement in the present application, and is within the protection scope of the present application, and will not be described in detail below.

Compared with the fourth generation mobile communication system, the fifth generation mobile communication system (5th-generation, 5G) has all-around requirements for various network performance indexes. For example, the capacity index is improved by 1000 times, the coverage requirement is wider, the time delay is ultrahigh and reliable, and the time delay is ultralow. On one hand, in consideration of rich high-frequency carrier frequency resources, in a hot spot area, in order to meet the requirement of 5G ultrahigh capacity, networking by using high-frequency small stations is more popular. The high-frequency carrier wave has poor propagation characteristics, is seriously attenuated by shielding and has a small coverage range, so a large number of densely deployed small stations are needed, and accordingly, the cost of providing optical fiber return for the densely deployed small stations is high, the construction difficulty is high, and an economic and convenient return scheme is needed; on the other hand, from the perspective of wide coverage requirements, network coverage is provided in some remote areas, the deployment difficulty of optical fibers is high, the cost is high, and a flexible and convenient access and return scheme also needs to be designed.

In order to further reduce the deployment cost and improve the deployment flexibility, 5G introduces an Integrated Access and Backhaul (IAB) technology, and an access link (access link) and a backhaul link (backhaul link) both adopt a wireless transmission scheme, thereby avoiding optical fiber deployment.

The present application refers to a node supporting integrated access and backhaul as a wireless backhaul node, which may also be referred to as a Relay Node (RN) or an IAB node (IAB node). For convenience of description, the IAB node is taken as an example for explanation. The IAB node may provide a radio access service for a terminal device, and traffic data of the terminal device is transmitted by being connected to a host node through a radio backhaul link by the IAB node, where the host node is also called an IAB host (IAB node) or a host base station (donor gbb). Illustratively, the DgNB may be an access network element having a complete base station function, or may be an access network element in a form of a Centralized Unit (CU) and a Distributed Unit (DU) which are separated. The DgNB is connected to a core network element serving the terminal device, for example, to a 5G core (5G core, 5GC), and provides a wireless backhaul function for the IAB node. For convenience of description, the centralized unit of the host node is referred to as a host CU (denor CU), and the distributed unit of the host node is referred to as a host du (denor du), where the denor CU may also be in a form in which a Control Plane (CP) and a User Plane (UP) are separated, for example, one CU is composed of one CU-CP and a plurality of CUs-UPs, which is not limited in this embodiment of the present application.

In consideration of the requirement of service transmission reliability, the IAB node may support multi-connectivity to cope with abnormal situations that may occur in the backhaul link, such as an abnormal situation of a link, such as a link interruption or blocking (block) and a load fluctuation, and improve the reliability guarantee of transmission. The multi-connection may be a Dual Connection (DC) connection, or may be two or more connections, which is not limited in the embodiment of the present application.

IAB networks support multi-hop and multi-connection networking, and therefore, multiple transmission paths may exist between the terminal device and the host node. In one path, there is a certain hierarchical relationship between IAB nodes, and between an IAB node and a host node serving the IAB node, in this embodiment, each IAB node regards a node providing backhaul service for the IAB node as a parent node, and accordingly, each IAB node can be regarded as a child node of its parent node. In other words, the parent node of an IAB node is the next hop node of the IAB node on the uplink, and the child node of an IAB node is the previous hop node of the IAB node on the uplink.

For convenience of description, the following defines basic terms used in the present application.

Next hop node (also called parent node) of uplink: a node that provides wireless backhaul link resources.

Uplink previous hop node (also called child node): nodes that use backhaul link resources for data transmission to and from a network, here a core network or other network on top of an access network, such as the internet, private network, etc.

Access Link (AL): an access link refers to a wireless link used when a terminal device communicates with a node (e.g., an IAB node, a donor node, or a donor DU) that provides access service to the terminal device, and includes links for uplink transmission and downlink transmission. Uplink transmission on the access link is also referred to as uplink transmission of the access link, and downlink transmission is also referred to as downlink transmission of the access link.

Backhaul Link (BL): the backhaul link refers to a wireless link used by a node to communicate with its parent node, and includes uplink and downlink transmission links. Uplink transmissions on the backhaul link are also referred to as uplink transmissions of the backhaul link, and downlink transmissions are also referred to as downlink transmissions of the backhaul link. Including but not limited to the aforementioned IAB nodes.

Path (path): the entire route from a sending node to a receiving node, a path consists of at least one link, which in this application means a connection between adjacent nodes.

In order to better understand the data transmission method and apparatus for a wireless backhaul network according to the embodiments of the present application, a description is first given below of a communication system applied to the embodiments of the present application. Referring to fig. 1, fig. 1 is a schematic diagram of a communication system according to an embodiment of the present application.

It should be noted that, the communication system to which the embodiment of the present application is applied includes, but is not limited to: a narrowband internet of things (NB-IoT) system, a Wireless Local Access Network (WLAN) system, an LTE system, a next generation 5G mobile communication system, or a communication system after 5G, such as an NR, device to device (D2D) communication system.

The communication system shown in fig. 1 is an IAB system. The IAB system includes a host node, IAB node A, IAB node B, IAB node C, and terminal devices served by the IAB node C (UE 1 is taken as an example in fig. 1). The parent node of the IAB node A is the host node, and the IAB node A is the parent node of the IAB node C. The parent node of the IAB node B is the host node, and the IAB node B is the parent node of the IAB node C. Thus, IAB node C has two parents. In other words, IAB node C includes two next-hop nodes on the uplink, and the uplink data packet to be sent via IAB node C can be transmitted to the host node through two paths. In the present application, the IAB node a is also referred to as a first next hop node of the IAB node C, and the IAB node B is also referred to as a second next hop node of the IAB node C.

For example, an uplink data packet of the UE1 may be transmitted to the host node through one or more IAB nodes, and then sent to the mobile gateway device (e.g., a user plane function Unit (UPF) in a 5G core network) by the host node, and a downlink data packet is received from the mobile gateway device by the host node, and then sent to the UE1 through the IAB node. In fig. 1, there are two available paths for data transmission between UE1 and the host node, path 1: UE1 ← → IAB node C ← → IAB node a ← → host node, path 2: UE1 ← → IAB node C ← → IAB node B ← → host node.

Optionally, the IAB system may further include other numbers of terminal devices and IAB nodes. As shown in fig. 1, the IAB system further includes an IAB node D and a terminal device (UE 2 is taken as an example in fig. 1) served by the IAB node D. The parent node of IAB node D is IAB node a and IAB node C may also serve UE 2.

Thus, there are three available paths for data transmission between UE 2 and the host node, path 1: UE 2 ← → IAB node C ← → IAB node a ← → host node, path 2: UE 2 ← → IAB node C ← → IAB node B ← → host node, path 3: UE 2 ← → IAB node D ← → IAB node a ← → host node.

The IAB network shown in fig. 1 is only exemplary, and in an IAB scenario where multi-hop and multi-connection are combined, there are still more other possibilities, for example, an IAB node under a host node and another host node forms a dual connection to provide services for a terminal device, and so on, which are not listed here.

It is understood that the host node may include, but is not limited to: an evolved node B (eNB), a Radio Network Controller (RNC), a Node B (NB), a Base Station Controller (BSC), a Base Transceiver Station (BTS), a home base station (e.g., home evolved node B (HNB)), a Base Band Unit (BBU), an LTE (evolved LTE, LTE) base station, an NR base station (next generation node B, gbb), and the like.

It should also be understood that terminal devices may include, but are not limited to: user Equipment (UE), a mobile station, an access terminal, a subscriber unit, a subscriber station, a mobile station, a remote terminal, a mobile device, a terminal, a wireless communication device, a user agent, a station (station, ST) in a Wireless Local Access Network (WLAN), a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device with wireless communication capability, a computing device, other processing devices connected to a wireless modem, a vehicle mounted device, a wearable device, a mobile station in a future 5G network, and a terminal device in a future evolved Public Land Mobile Network (PLMN) network, etc.

The IAB node is a specific name for a relay node in an IAB network, and does not limit the scheme of the present application. The IAB node is used only for the description, and does not indicate a scenario that the scheme of the present application is only used for NR, and in the present application, the IAB node may refer to any node or device with a relay function in a general way.

In addition, there are many alternatives for the user plane protocol architecture of IAB, which can be divided into the IAB architecture of layer 2 and the IAB architecture of layer 3. The IAB node shown in fig. 1, e.g., IAB node A, IAB node B, IAB node C, may have two existing forms: one is to exist as an independent access node, which can independently manage terminal equipment accessing to an IAB node, and this type of relay generally needs to have complete base station protocol stack functions, such as Radio Resource Control (RRC) functions, and this type of relay is generally called layer 3 relay; while another form of relay node and host node can jointly perform user management, such relay usually has only partial layer 2 protocol stack function of the base station, and is called layer 2 relay. The layer 2 relay generally exists as a DU of a home node under a control and bearer split (CU-DU) architecture of NR, and performs control plane communication with the home node or a CU of the home node through an F1application protocol (F1application protocol, F1AP) interface.

Taking UE as an example, in an IAB architecture of layer 2, a Packet Data Convergence Protocol (PDCP) layer and a Service Data Application Protocol (SDAP) layer that are peer to each other with the UE are located on a host node or a CU of the host node. The IAB node performs forwarding of UE service data in a Radio Link Control (RLC) layer and below, that is, a forwarded data packet is a PDCP layer Protocol Data Unit (PDU) of the UE.

For example, for a certain protocol layer, an information Unit from a higher protocol layer above the protocol layer may be referred to as a Service Data Unit (SDU), and after processing by the protocol layer, an information Unit directed to a next protocol layer may be referred to as a PDU. For example, the information units received by the PDCP layer from a higher protocol layer may be referred to as PDCP SDUs, and the information units processed by the PDCP layer and directed to a next layer may be referred to as PDCP PDUs. The processing here may include assigning Sequence Number (SN), header compression, ciphering, integrity protection, packetizing header, and the like.

In addition, an adaptation layer (adaptation layer) is introduced in the backhaul link of the IAB node in layer 2, and the adaptation layer carries some information related to the guarantee of routing and quality of service (QoS), UE identification, and bearer, and provides routing and QoS mapping functions required for data forwarding. It should be understood that the adaptation layer may be a separate protocol layer, or may be a sub-layer or a sub-module of an existing protocol layer, for example, a sub-layer of an RLC layer, or a sub-layer of a MAC layer, which is not limited in this embodiment of the present application. It should also be understood that the newly introduced protocol layer with routing and QoS mapping functions is referred to as an adaptation layer only for convenience of description, but in an actual network, the protocol layer may have other names, and the embodiment of the present application does not limit this.

Optionally, in a case that the adaptation layer may be an independent protocol layer, the deployment of the adaptation layer is divided into two manners, and for different deployment manners, the processing manners of the data packet are different, and the two deployment manners are introduced below respectively.

In the first mode, the adaptation layer is deployed above the RLC layer, and this deployment mode has the following characteristics:

1. mapping of the data packets to the RLC channel (RLC channel) of the backhaul link may be performed in the adaptation layer, and the RLC channel of the backhaul link may be in one-to-one correspondence with UE bearers (UE bearers), or multiple UE bearers may be aggregated and mapped to the RLC channel of the same backhaul link.

2. The IAB node may directly perform mapping from the RLC channel of the previous-hop link to the RLC channel of the next-hop link between the backhaul links, or may perform mapping from the UE bearer to the RLC channel of the next-hop link.

3. The RLC layer entity of the IAB node on the backhaul link corresponds to the Logical Channel (LCH) or the RLC bearer or the RLC channel of the IAB node on the backhaul link.

4. For the RLC Acknowledged Mode (AM), only the automatic repeat request (ARQ) mode can be adopted.

In the second mode, the adaptation layer is deployed below the RLC layer and above a Medium Access Control (MAC) layer, that is, the adaptation layer is deployed between the MAC layer and the RLC layer, and this deployment mode has the following characteristics:

1. the mapping of the data packets to the LCH of the backhaul link may be performed at the adaptation layer, where the LCH of the backhaul link may correspond to the UE bearers one to one, or multiple UE bearers may be aggregated and mapped to the LCH of the same backhaul link.

2. The IAB node may directly perform mapping from the LCH of the previous-hop link to the LCH of the next-hop link between backhaul links, or may perform mapping and/or aggregation from the UE bearer to the LCH of the next-hop link.

3. The RLC entities of the IAB node on the return link correspond to the UE bearer one by one.

4. For the RLC Acknowledged Mode (AM), an end-to-end ARQ mode (end-to-end ARQ) or a hop-by-hop ARQ mode (hop-by-hop ARQ) may be used.

5. Either end-to-end reassembly (reassembling) or hop-by-hop reassembly may be employed.

Illustratively, the end-to-end ARQ modes are: the ARQ-related functions are configured only on the RLC entities at both ends, and the RLC layer of the middle IAB node has segmentation and/or re-segmentation functions without performing ARQ functions (including feedback on packet reception as a receiving node and retransmission of unacknowledged packets as a transmitting node), wherein segmentation is for one complete RLC service data unit SDU and re-segmentation is for one RLC SDU segment. Taking uplink transmission as an example, the UE sends a data packet to the host node through the IAB node, the host node feeds back an Acknowledgement (ACK) message to the IAB node when receiving the data packet correctly, and feeds back a non-acknowledgement (NACK) message to the IAB node when not receiving the data packet correctly, the IAB node only forwards these messages, and when the host node feeds back a NACK message, the UE sends the data packet to the host node again through the IAB node until the host node feeds back an ACK message for the data packet.

And the hop-by-hop ARQ mode is: all nodes in the IAB network, including the IAB nodes, are configured with ARQ-related functionality. The RLC layer of the IAB node has segmentation and/or re-segmentation functionality as well as ARQ related functionality. That is, the IAB node can not only forward the data packet, but also feed back to the node sending the data packet (the previous hop node of the IAB node) whether the data packet is correctly received.

Illustratively, the data packet can adopt two modes of hop-by-hop recombination and end-to-end recombination in the transmission process.

The hop-by-hop recombination is as follows: when a sending node sends a data packet to a receiving node through N intermediate nodes, on each segment of link, if the sending node performs segmentation processing on RLC SDUs in an RLC layer, the intermediate node may reassemble (reassembling) the segments in the RLC layer of the receiving side, and thus, the complete RLC SDUs can be recovered.

The end-to-end reorganization is: when a sending node sends a data packet to a receiving node through N intermediate nodes, the sending node can perform segmentation processing on RLC SDUs on an RLC layer, the N intermediate nodes between the sending node and the receiving node can also perform segmentation processing on complete RLC SDUs, or the segmentation processing on the RLC SDU (segment) continues to be performed, but the intermediate nodes do not perform reassembly on a receiving side of the receiving node until the RLC SDU segments are transmitted to the receiving node, and the receiving node can reassemble all received segments on the RLC layer of the receiving side of the receiving node to recover the complete RLC SDUs.

It can be understood that, when the IAB network adopts the hop-by-hop ARQ mode, the corresponding reassembly mode is also hop-by-hop reassembly; when the end-to-end ARQ mode is adopted, the reassembly mode may be hop-by-hop reassembly or end-to-end reassembly.

The wireless backhaul node may have the role of a Mobile Terminal (MT), in other words, the wireless backhaul node may include at least one MT unit, for example, the wireless backhaul node may include the role of only one MT, which is a multi-connection capable MT, and the wireless backhaul node may establish backhaul connections with multiple parent nodes of the wireless backhaul node through the MT; also for example, the wireless backhaul node may include a plurality of MTs, each MT of the plurality of MTs establishing a connection with a parent node of the wireless backhaul node as an independent backhaul link of the wireless backhaul node. The MT unit includes protocol layers such as a Packet Data Convergence Protocol (PDCP) layer, an adaptation layer, a Radio Link Control (RLC) layer, a Medium Access Control (MAC) layer, and a Physical (PHY) layer. The present application proposes a method for data transmission in a wireless backhaul network for the case that the wireless backhaul node includes an MT unit.

Fig. 2 shows a schematic flow chart of a data transmission method 200 for a wireless backhaul network according to an embodiment of the present application. The method 200 may be applied to the communication system 100 shown in fig. 1, but the embodiment of the present application is not limited thereto. The wireless backhaul network of the embodiments of the present application includes a wireless backhaul node and a host node, where the wireless backhaul node has a plurality of next-hop nodes on an uplink.

S210, a sending node generates a first data packet;

s220, the sending node sends the first data packet to a receiving node; correspondingly, the receiving node receives the first data packet from the sending node;

s230, the receiving node parses the first data packet;

the first data packet includes a first PDCP Protocol Data Unit (PDU) generated by a first packet data convergence protocol PDCP entity, the first PDCP PDU includes a first packet header and a first load, the first packet header includes identification information of a PDCP layer of the first PDCP PDU, the first load includes identification information of a first protocol layer of the first load, the first data packet further includes indication information of the first PDCP PDU, the indication information is used for indicating that the first load in the first PDCP PDU is data of the first protocol layer, the first protocol layer corresponds to at least one PDCP entity in the sending node, and the at least one PDCP entity includes the first PDCP entity.

Illustratively, a transmitting node may generate a first data packet and transmit the first data packet to a receiving node. The transmitting node includes a PDCP layer and a first protocol layer located above the PDCP layer, and the first protocol layer corresponds to at least one PDCP entity of the PDCP layer. Here, "corresponding" indicates that a packet can be transferred between the first protocol layer and at least one PDCP entity. Therefore, the first PDCP PDU of the first packet is obtained by the sending node performing first protocol layer encapsulation, adding the identification information of the first protocol layer to the first protocol layer, performing PDCP layer encapsulation, and adding the identification information of the PDCP layer to the PDCP layer. Based on such a processing order, the first header of the first PDCP PDU includes identification information of the PDCP layer of the first PDCP PDU, and the first payload of the first PDCP PDU includes identification information of the first protocol layer of the first payload. In order to facilitate the distinction by the receiving node, the first data packet further includes indication information of the first PDCP PDU, which is used to indicate that the first payload in the first PDCP PDU is data of the first protocol layer, so that the receiving node transfers the first payload in the first PDCP PDU to the corresponding first protocol layer for processing according to the indication information. It should be understood that the first payload may include user plane data and may also include control plane signaling, which is not limited in this embodiment of the present application.

And the receiving node receives the first data packet from the sending node, analyzes the first data packet and acquires a first PDCP PDU of the first data packet. The receiving node may obtain indication information of a first PDCP PDU in the first data packet, and deliver a first payload in the first PDCP PDU to a first protocol layer of the receiving node according to the indication information. The receiving node may further obtain identification information of a PDCP layer of the first PDCP PDU in the first header of the first PDCP PDU, so as to determine a precedence order of the first PDCP PDU on a transmission link corresponding to the first PDCP entity, so as to perform a sorting process with other PDCP PDUs generated by the first PDCP entity. The receiving node may further obtain identification information of a first protocol layer of the first load in the first load of the first PDCP PDU, so as to determine a precedence order of the first load in the first PDCP PDU on transmission links corresponding to the plurality of PDCP entities, so as to perform a sorting process with loads in PDCP PDUs generated by other PDCP entities.

Optionally, the first payload may further include a first sub-packet header and a first sub-payload, where the identification information of the first protocol layer of the first payload is carried in the first sub-packet header, and the first sub-payload is data that actually needs to be processed. Generally, during the first protocol layer processing, the identification information of the first protocol layer of the first payload is that the first protocol layer is allocated to the received SDU, and is carried in the header portion of the newly generated PDU after being processed. The identification information of the first protocol layer of the first payload is a sequence number SN or time for identifying the first payload or the first sub-payload.

Therefore, the data transmission method for the wireless backhaul network of the embodiment of the present application, by a sending node, sends a first data packet including a first PDCP PDU, the first PDCP PDU includes identification information of a PDCP layer of the first PDCP PDU and identification information of a first protocol layer of the first payload, carrying indication information of a first PDCP PDU in a first data packet, for indicating that a first payload in the first PDCP PDU is data of a first protocol layer, so that the receiving node transmits the first payload in the first data packet to the first protocol layer of the receiving node according to the indication information, and processes the first payload in the first PDCP PDU according to the identification information of the PDCP layer of the first PDCP PDU and the identification information of the first protocol layer of the first payload, therefore, data transmission in the wireless backhaul network is completed, the sending node and the receiving node are ensured to be consistent in understanding, and errors are not easy to occur.

It should be understood that the first protocol layer may be an F1application protocol (F1application protocol, F1AP) layer, or an additional layer between the F1AP layer and the PDCP layer, which is not limited in this embodiment of the present application. The F1AP layer is located above the PDCP layer, and the transmitting node and the receiving node each have a first protocol layer and a PDCP layer.

As an optional embodiment, the sending node is a wireless backhaul node, and the receiving node is a host node; or, the sending node is a host node, and the receiving node is a wireless backhaul node.

As an optional embodiment, the at least one PDCP entity corresponds to at least one MT unit of the mobile terminal one to one; or, the number of the at least one PDCP entity is multiple, and multiple PDCP entities of the at least one PDCP entity correspond to one MT unit of the at least one MT unit.

As an optional embodiment, the sending node has a plurality of next hop nodes, and the sending node sends the first data packet to the receiving node, including: the sending node sends the first data packet to the receiving node through a first next hop node in the plurality of next hop nodes; the method further comprises the following steps: the sending node sends a second data packet to the receiving node through a second next hop node of the plurality of next hop nodes, wherein the second data packet includes a second PDCP PDU generated by a second PDCP entity of the at least one PDCP entity, the second PDCP PDU includes a second header and the first payload, the second header includes identification information of a PDCP layer of the second PDCP PDU, the second data packet further includes indication information of the second PDCP PDU, and the indication information of the second PDCP PDU is used to indicate that the first payload of the second PDCP PDU is data of the first protocol layer.

Illustratively, the sending node may have multiple next hop nodes, i.e., there are multiple transmission paths from the sending node to the receiving node. In this case, the sending node may have a data copying capability, and copy the first payload in the first packet into multiple copies to be sent on different paths respectively. The transmitting node may transmit a first data packet including a first payload through a first next-hop node of the plurality of next-hop nodes while transmitting a second data packet including the first payload through a second next-hop node of the plurality of next-hop nodes.

As an optional embodiment, the receiving node includes a plurality of previous-hop nodes, and the receiving node receives a first packet from a sending node, including: the receiving node receiving the first data packet from the transmitting node through a first previous-hop node of the plurality of previous-hop nodes; the method further comprises the following steps: the receiving node receives a second data packet from the transmitting node through a second previous hop node of the plurality of previous hop nodes, wherein the second data packet comprises a second PDCP PDU generated by a second PDCP entity of the at least one PDCP entity, the second PDCP PDU comprises a second header and a second payload, the second header comprises identification information of a PDCP layer of the second PDCP PDU, the second payload comprises identification information of a first protocol layer of the second payload, the second data packet further comprises indication information of the second PDCP PDU, and the indication information of the second PDCP PDU is used for indicating that the second payload of the second PDCP PDU is data of the first protocol layer; the receiving node parses the second packet.

Illustratively, the receiving node may include a plurality of previous hop nodes corresponding to the transmitting node, i.e., the receiving node may receive the data packet from the transmitting node through a plurality of transmission paths. In this case, the receiving node may receive a packet from the transmitting node through a plurality of previous-hop nodes and process the plurality of packets. The receiving node may receive a first data packet from the transmitting node via a first previous-hop node of the plurality of previous-hop nodes while receiving a second data packet from the transmitting node via a second previous-hop node of the plurality of previous-hop nodes.

Illustratively, the receiving node includes a plurality of previous-hop nodes, and the receiving node is considered as a whole as a wireless backhaul node or a host node, regardless of the existence of the host node in the form of CU and DU separation. In a special case, when the receiving node is a host CU in the host node or a CU-CP of the host node, the last-hop node of the receiving node refers to the last-hop node of the host DU in the host node when a plurality of transmission paths between the node and the receiving node share the F1 interface between the same host DU and the host CU.

In an embodiment of the present application, the second data packet includes a second PDCP PDU generated by the second PDCP entity, a structure of the second PDCP PDU is similar to that of the first data packet, a second header in the second PDCP PDU includes identification information of a PDCP layer of the second PDCP PDU, a second payload in the second PDCP PDU includes identification information of a first protocol layer of the second payload, and the second data packet further includes indication information of the second PDCP PDU, which is used to indicate that the second payload in the second PDCP PDU is data of the first protocol layer.

Furthermore, the second data packet is from the sending node, i.e. the second data packet is from the same sending node as the first data packet, but it should be understood that the second data packet may also be from other nodes. In a case where the second packet and the first packet both come from the sending node, the second payload in the second packet may be the same as or different from the first payload in the first packet, and this is not limited in this embodiment of the present application.

In the data transmission method for the wireless backhaul network according to the embodiment of the present application, a plurality of transmission paths exist between the sending node and the receiving node, so that the sending node can send a plurality of data packets through different transmission paths, and the receiving node can receive the plurality of data packets through corresponding paths and process the plurality of data packets.

As an optional embodiment, the method further comprises: the receiving node acquires identification information of a first protocol layer of the first load and identification information of a first protocol layer of the second load; and the receiving node processes the first load and the second load in sequence according to the identification information of the first protocol layer of the first load and the identification information of the first protocol layer of the second load.

For example, after receiving the first packet and the second packet, the receiving node may obtain the identification information of the first protocol layer of the first payload from the first packet, and obtain the identification information of the first protocol layer of the second payload from the second packet, and then, the receiving node may process the first payload in the first PDCP PDU and the second payload in the second PDCP PDU in order according to the identification information of the first protocol layer of the first payload and the identification information of the first protocol layer of the second payload. Assuming that the identification information of the first protocol layer is a sequence number allocated to the first protocol layer, for example, the identification information of the first protocol layer of the first payload is 3, and the identification information of the first protocol layer of the second payload is 5, the receiving node may process the first payload in the first PDCP PDU first, and then process the second payload in the second PDCP PDU.

As an alternative embodiment, said sequentially processing said first load and said second load comprises: the receiving node detects whether the identification information of the first protocol layer of the first load is the same as the identification information of the first protocol layer of the second load; if the identification information of the first protocol layer of the first payload is the same as the identification information of the first protocol layer of the second payload, the receiving node processes the first payload or the second payload.

Due to the capability of data replication, the sending node can replicate the first payload into multiple copies and respectively send the copies on different paths. Therefore, the receiving node needs to repeatedly detect the payload in the packets from different paths. Specifically, the receiving node may determine whether the identification information of the first protocol layer of the first payload is the same as the identification information of the first protocol layer of the second payload, and if the identification information of the first protocol layer of the first payload is the same as the identification information of the first protocol layer of the second payload, it indicates that the first payload is the same as the second payload, and the receiving node may only need to process one of the first payload and the second payload.

Fig. 3 shows a schematic flow chart of another data transmission method 300 for a wireless backhaul network according to an embodiment of the present application. The method 300 may be applied to the communication system 100 shown in fig. 1, but the embodiment of the present application is not limited thereto.

S310, a host node sends a first message to a wireless backhaul node, wherein the first message carries an identifier of at least one PDCP entity of the wireless backhaul node, and the identifier of the at least one PDCP entity is used for a layer F1application protocol F1AP of the wireless backhaul node to correspond to the at least one PDCP entity; correspondingly, the wireless backhaul node receives a first message from the host node.

Illustratively, the first message is for configuring that there is a correspondence between the F1application protocol F1AP layer (or F1AP entity) of the wireless backhaul node and at least one PDCP entity of the wireless backhaul node.

S320, the wireless backhaul node configures according to the first message, and sends a second message to the host node, where the second message is used to indicate a result of the wireless backhaul node configuring according to the first message; correspondingly, the host node receives a second message from the wireless backhaul node.

Illustratively, the donor node may send a first message to the wireless backhaul node configuring a correspondence between the F1AP layer (or F1AP entity) of the wireless backhaul node and the at least one PDCP entity, where the correspondence means that the F1AP message may be transmitted between the F1AP layer and the at least one PDCP entity. For uplink transmission, the wireless backhaul node may send a F1AP message to one of the at least one PDCP entity through the F1AP layer, and then the PDCP entity transmits the F1AP message to the host node through the corresponding path, and the host node receives the F1AP message through the corresponding PDCP entity and transmits the F1AP message to the F1AP layer at the host node that is peer to the wireless backhaul node. For downlink transmission, the host node may send a F1AP message to one of the at least one PDCP entity through the F1AP layer, and then the PDCP entity transmits the F1AP message to the wireless backhaul node through a corresponding path, and the wireless backhaul node receives the F1AP message through the corresponding PDCP entity and transmits the F1AP message to the F1AP layer of the wireless backhaul node for processing.

When the host node is in a CU-DU separated form, the host node may also be a centralized unit CU of the host node, and when the host CU is in a User Plane (UP) and Control Plane (CP) separated form, the host node may also be a CU-CP, which is not limited in this embodiment.

The first message may carry the configured identifier of the at least one PDCP entity, so that the wireless backhaul node may establish a correspondence between the F1AP layer and the at least one PDCP entity directly according to the identifier of the at least one PDCP entity. Since the wireless backhaul node may have the role of the mobile terminal MT, the PDCP entity is included in the MT unit of the wireless backhaul node, and corresponds to the radio bearer used for transmitting the F1AP message, optionally, the identification of the at least one PDCP entity may be implemented by the identification of the MT and the identification of the radio bearer. Optionally, the first message may further carry an identifier of the wireless backhaul node, so that the wireless backhaul node distinguishes the message from the host node. Alternatively, in case there is only one MT in the wireless backhaul node, the identification of the MT may be the identification of the wireless backhaul node.

It should be understood that the host node may configure the same correspondence between the F1AP layer and the PDCP entity for multiple wireless backhaul nodes, or may configure an independent correspondence between the F1AP layer and the PDCP entity for each wireless backhaul node, which is not limited in this embodiment of the present application. If the host node needs to configure different corresponding relationships for each wireless backhaul node, the first message sent to each wireless backhaul node needs to carry an identifier of the corresponding wireless backhaul node.

Illustratively, there is a correspondence between the above-mentioned F1AP layer and at least one PDCP entity, and there may be two cases. Assuming that the wireless backhaul node includes m PDCP entities, the first case is that there is a corresponding relationship between the F1AP layer and the m PDCP entities, where the m PDCP entities are the at least one PDCP entity; another case is that the F1AP layer has a corresponding relationship with n PDCP entities of the m PDCP entities, where the n PDCP entities are the at least one PDCP entity. Wherein m and n are positive integers, and m is greater than n.

After receiving the first message sent by the host node, the wireless backhaul node may perform configuration according to the first message, and feed back a configuration result to the host node through a second message, where the configuration result may be a configuration success or a configuration failure. For example, the second message may include a bit value, where the bit value is 1 to indicate that the configuration is successful, and the bit value is 0 to indicate that the configuration is failed, or the second message includes a plurality of bit values to indicate that the F1AP layer corresponds to each PDCP entity in the at least one PDCP entity, which is not limited in this embodiment. It should be understood that, while configuring the above-mentioned corresponding relationship for the wireless backhaul node, the host node itself also configures the same corresponding relationship, so as to ensure that the protocol layer architectures of the wireless backhaul node and the host node are consistent.

It should be understood that the protocol layer corresponding to the above F1AP layer may be F1AP or T1AP, and the application does not limit the specific names of the protocol layers. The protocol layer may be used to establish, maintain, and update the interface between the DU of the wireless backhaul node and the host CU of the host node, may perform configuration management on the context of the terminal device, and may also transmit RRC messages of the terminal device.

As an optional embodiment, the first message is further used to instruct one of the at least one PDCP entity to preferentially transmit data of the F1AP layer.

As an optional embodiment, the method further comprises: the host node sending a third message to the wireless backhaul node, the third message indicating that data of the F1AP layer is preferentially transmitted by one of the at least one PDCP entity; correspondingly, the wireless backhaul node receives a third message sent by the host node, where the third message is used to indicate that data of the F1AP layer is preferentially transmitted by one of the at least one PDCP entity.

In addition, the host node may also configure whether to allow the layer F1AP of the wireless backhaul node to perform replication (duplication) operation through the above-mentioned first message or other additional messages, i.e., configure whether the wireless backhaul node has a data replication function, so that the wireless backhaul node can transmit the same load through different transmission paths. The data replication function may be activated by default once configured, or may be configured first by the host node and then activated by additional other messages, which is not limited in this embodiment of the present application.

As an alternative embodiment, the first message and the second message are F1AP messages; or, the first message and the second message are Radio Resource Control (RRC) messages.

For example, the first message and the second message may be RRC messages, and the first message may be at least one independent message respectively sent by the host node to at least one MT unit of the wireless backhaul node, and one of the at least one MT unit may correspond to the at least one PDCP entity. Correspondingly, the wireless backhaul node can send at least one second message to the host node via the at least one MT unit, respectively, for responding to the first message.

The first message and the second message may also be F1AP messages, in which case the first message may be sent by the host node to an MT unit of the wireless backhaul node via a default transmission path and then to the F1AP layer of the wireless backhaul node via the MT unit of the wireless backhaul node. Correspondingly, the wireless backhaul node sends a second message to the host node through the layer F1AP for responding to the first message.

Fig. 4 shows a schematic flow chart of another data transmission method 400 for a wireless backhaul network according to an embodiment of the present application. The method 400 may be applied to the communication system 100 shown in fig. 1, but the embodiment of the present application is not limited thereto.

S410, the host node sends a fourth message to the wireless backhaul node, where the fourth message carries an identifier of the at least one adaptation layer entity or a cell group identifier of at least one parent node corresponding to the at least one adaptation layer entity, and the identifier of the at least one adaptation layer entity is used for a packet data convergence protocol PDCP entity of the wireless backhaul node to correspond to the at least one adaptation layer entity; the wireless backhaul node correspondingly receives a fourth message from the host node.

S420, the wireless backhaul node configures according to the fourth message, and sends a fifth message to the host node, where the fifth message is used to indicate a configuration result of the wireless backhaul node for the fourth message; the host node correspondingly receives a fifth message from the wireless backhaul node.

Illustratively, the host node may send a fourth message to the wireless backhaul node configuring a correspondence between the PDCP entity of the wireless backhaul node and the at least one adaptation layer entity, where the correspondence means that PDCP PDUs can be transmitted between the PDCP entity and the at least one adaptation layer entity. In the embodiment of the present application, the adaptation layer is located above the RLC layer. For uplink transmission, the wireless backhaul node may send a PDCP PDU to one of the at least one adaptation layer entity through the PDCP entity, and then the adaptation layer entity transmits the PDCP PDU to the host node through a corresponding path, and the host node receives the PDCP PDU through the corresponding adaptation layer entity and transmits the PDCP PDU to the PDCP entity of the host node for processing. For downlink transmission, the host node may send a PDCP PDU to one of the at least one adaptation layer entity through the PDCP entity, and then the adaptation layer entity transmits the PDCP PDU to the wireless backhaul node through a corresponding path, and the wireless backhaul node receives the PDCP PDU through the corresponding adaptation layer entity and transmits the PDCP PDU to the PDCP entity of the wireless backhaul node for processing.

The fourth message may carry the configured identifier of the at least one adaptation layer entity, so that the wireless backhaul node may directly establish a corresponding relationship between the PDCP entity and the at least one adaptation layer entity according to the identifier of the at least one adaptation layer entity. Alternatively, the fourth message may carry a cell group identifier of at least one parent node corresponding to the at least one adaptation layer entity, for example, the adaptation layer entities of the wireless backhaul node and the parent node of the wireless backhaul node are in one-to-one correspondence, and the host node may indicate the at least one parent node of the wireless backhaul node to the wireless backhaul node through the cell group identifier, so that the wireless backhaul node determines the adaptation layer entity corresponding to the at least one parent node. Optionally, the fourth message may further carry an identifier of the wireless backhaul node, so that the wireless backhaul node distinguishes the message from the host node.

For example, the host node may configure the same corresponding relationship between the PDCP entity and the adaptation layer entity for multiple wireless backhaul nodes, or may configure an independent corresponding relationship between the PDCP entity and the adaptation layer entity for each wireless backhaul node, which is not limited in this embodiment of the present application. If the host node needs to configure different corresponding relationships for each wireless backhaul node, the fourth message sent to each wireless backhaul node needs to carry the identifier of the corresponding wireless backhaul node.

Illustratively, there is a corresponding relationship between the PDCP entity and the at least one adaptation layer entity, and there may be two cases. Assuming that the wireless backhaul node includes p adaptation layer entities, the first case is that there is a corresponding relationship between the PDCP entity and the p adaptation layer entities, and the p adaptation layer entities are the at least one adaptation layer entity; in another case, the PDCP entity and q adaptation layer entities of the p adaptation layer entities have a corresponding relationship, and the q adaptation layer entities are the at least one adaptation layer entity. Wherein p and q are both positive integers, and p is greater than q.

After receiving the fourth message sent by the host node, the wireless backhaul node may perform configuration according to the fourth message, and feed back a configuration result to the host node through a fifth message, where the configuration result may be a configuration success or a configuration failure. For example, the fifth message may include a bit value, where the bit value is 1 to indicate that the configuration is successful, and the bit value is 0 to indicate that the configuration is failed, or the fifth message includes a plurality of bit values to indicate that the PDCP entity and each of the at least one adaptation layer entity are configured successfully or unsuccessfully, which is not limited in this embodiment of the present application. Illustratively, while configuring the above corresponding relationship for the wireless backhaul node, the host node itself also configures the same corresponding relationship, so as to ensure that the protocol layer architectures of the wireless backhaul node and the host node are consistent.

As an optional embodiment, the fourth message is further used to instruct that data of the PDCP layer is preferentially transmitted by one of the at least one adaptation layer entity.

As an optional embodiment, the method further comprises: the host node sending a sixth message to the wireless backhaul node, the sixth message indicating that data of the PDCP layer is preferentially transmitted by one of the at least one adaptation layer entity; correspondingly, the wireless backhaul node receives a sixth message sent by the host node.

Illustratively, in the fourth message, a certain adaptation layer entity of the configured at least one adaptation layer entity may be indicated as a preferred adaptation layer entity, that is, data of the PDCP layer is preferentially transmitted by the adaptation layer entity. The data of the PDCP layer herein refers to control plane data, and may specifically be signaling of the control plane. The host node may also configure a preferred adaptation layer entity for the wireless backhaul node through a sixth message, which is not limited in this embodiment of the present application.

As an alternative embodiment, the fourth message and the fifth message are F1AP messages; or, the fourth message and the fifth message are Radio Resource Control (RRC) messages.

Illustratively, the fourth message and the fifth message may be RRC messages, and then the fourth message may be a message sent by the host node to an MT unit of the wireless backhaul node, the MT unit including a PDCP entity. Correspondingly, the wireless backhaul node can send a fifth message to the host node via the MT unit for responding to the fourth message.

The fourth message and the fifth message may also be F1AP messages, in which case the fourth message may be sent by the host node to the MT unit of the wireless backhaul node via a default transmission path and then sent to the F1AP entity of the wireless backhaul node via the MT unit of the wireless backhaul node. Correspondingly, the wireless backhaul node sends a fifth message to the host node through the F1AP entity for responding to the fourth message.

Next, referring to fig. 5 to fig. 12, taking the terminal device as UE1, the wireless backhaul node as IAB node C, the first next hop node as IAB node a, and the second next hop node as IAB node B as examples, the data transmission method for the wireless backhaul network according to the present application will be described in detail.

Fig. 5-9 show networking diagrams and protocol stack diagrams of multiple connections of a multi-MT based wireless backhaul network according to an embodiment of the present application. It should be understood that, a plurality of the references herein refer to 2 or more than 2, only 2 MT scenarios are shown in the figures, and the illustration is made only for the case where the wireless backhaul node includes 2 MTs, and actually, more MTs may be configured according to the number of paths that the wireless backhaul node needs to support, and similarly, the embodiment of the present application does not limit this case where the wireless backhaul node includes more MTs.

Fig. 5 is a diagram illustrating multiple connections of a multi-MT based wireless backhaul network. Corresponding to the communication system shown in fig. 1, UE1 is connected to a DU of an IAB node C, and accesses to an IAB network through the IAB node C, where the IAB node C has two next-hop nodes, i.e., two parents, IAB node a and IAB node B on the uplink. The IAB node C includes 2 MT units, MT1 and MT 2 respectively. MT1 is connected to the DU of IAB node a and MT 2 is connected to the DU of IAB node B, so that the IAB node C has two independent transmission paths to the home node. Each of the IAB node a and the IAB node B includes 1 MT unit, and the IAB node a and the IAB node B are connected to the host DU of the host node through the respective MT units. The host node of fig. 5 is an access network element in which the host CU and the host DU are separate entities, and the host CU includes a CU-CP and a CU-UP.

In the networking scenario described above, there may be multiple possible situations in the protocol stack of the backhaul link.

Fig. 6 shows a schematic diagram of a control plane protocol stack based on multiple MTs. The UE1 includes a Radio Resource Control (RRC) layer, a Packet Data Convergence Protocol (PDCP) layer, a Radio Link Control (RLC) layer, a Medium Access Control (MAC) layer, and a Physical (PHY) layer. Wherein the host node includes a protocol layer peered to the RRC layer and the PDCP layer of the UE 1. When the host node is in a CU-DU separation form, a protocol layer equivalent to the RRC layer and the PDCP layer of the UE1 is located on the host CU of the host node. The host CU shown in fig. 6 is a separate UP and CP, and a peer protocol layer to the RRC layer and the PDCP layer of the UE1 is located on the CU-UP of the host node.

In the DU part of the IAB node C, the F1AP protocol layer of the IAB node is peer-to-peer with the F1AP protocol layer at the CU-CP of the donor node, and the PDU (or referred to as F1AP message) of the F1AP layer may encapsulate the RRC message of the UE1, or may encapsulate only the management message of the donor node to the IAB node, for example, the F1 interface management related message or the UE context configuration related message. The F1 interface is the interface between the DU part of the IAB node and the CU-CP of the host node. The IAB node C includes MT1 and MT 2, and the MT1 and MT 2 respectively have their own protocol layers, which are an adaptation layer, an RLC layer, an MAC layer, and a PHY layer from top to bottom. Wherein the adaptation layer is operable to perform packet routing for determining a next hop node and QoS mapping for determining a radio bearer (or RLC bearer, or RLC channel, or Logical Channel (LCH)) of a backhaul link for a packet to be sent. Any one or more of the following information may be carried in the adaptation layer: information for packet routing (e.g., an identity of the UE, an identity of the donor node, an identity of the IAB node, etc.), information for QoS mapping (e.g., an identity of a radio bearer of the UE, a QoS Class Identifier (QCI), a 5G QoS identifier (5G QoS identifier, 5QI), etc.), packet type indication information (e.g., indication information to distinguish user plane data, RRC messages, F1AP messages), flow control feedback information, etc. Illustratively, the function of the adaptation layer can also be extended by extending the function of any protocol layer (such as RLC layer, MAC layer, PDCP layer, etc.) or any plurality of protocol layers in the existing layer 2 without requiring additional protocol layers.

In the IAB node C, the F1AP layer at the DU has a corresponding relationship with the PDCP layer of MT1 and the PDCP layer of MT 2, and specifically, an uplink packet generated by the F1AP layer of the IAB node C may be transferred to the PDCP layer of MT1 for processing, and then sent to the host node through the IAB node a, or transferred to the PDCP layer of MT 2 for processing, and then sent to the host node through the IAB node B. The host node has a peer-to-peer protocol layer shown in fig. 6, and is configured to process the received uplink data packet. For the downlink data packet sent by the host node, the processing manner is similar, and details are not described here. The uplink data packet generated by the layer F1AP of the IAB node C may include an uplink RRC message of the UE.

For example, the correspondence relationship between the F1AP layer at the DU and the PDCP layer of the MT1 and the PDCP layer of the MT 2 may be that the host node configures the wireless backhaul node through the first message before data transmission, where the first message may be an F1AP message or an RRC message, which is not limited in this embodiment of the present application.

Illustratively, in order to enable the F1AP layer of the IAB node C to have the selection capability of the multipath routing, the donor node may send a first message to the IAB node C, the first message carrying configuration information for configuring an F1AP entity of the IAB node C, a radio bearer and/or a PDCP entity corresponding to the MT1 and/or the MT 2, indicating that the F1AP message may be sent via a radio bearer a of the MT1, or indicating that the F1AP message may be sent via a radio bearer b of the MT 2, or indicating that the F1AP message may be sent via the radio bearer a of the MT1 and the radio bearer b of the MT 2.

Optionally, when the F1AP entity of the IAB node C is configured to correspond to the radio bearers (or corresponding PDCP entities) of the MT1 and MT 2, the donor node (or donor CU, or CU-CP) may further designate one of the M T units as a preferred (primary) node, or designate a specific bearer of one of the MTs as a preferred bearer, that is, the IAB node C may preferentially select the MT or the specific bearer of the MT when it needs to transmit the F1AP message. If the donor node does not specify a preferred node and/or bearer, the priority of both is considered the same, and the specific MT to select for transmission of the F1AP message is determined by the IAB node C.

The first message may be an F1AP message sent to the F1AP entity of the IAB node C, or two separate RRC messages sent to MT1 and MT 2 of the IAB node C, respectively.

Alternatively, the IAB node C may send a second message to the donor node (or donor CU, or CU-CP) indicating the configuration result, e.g., configuration complete or configuration failure. Similar to the first message, the second message may also be an F1AP message, or an RRC message, the specific type depending on the type of the first message. Illustratively, if the second message is an RRC message, then MT1 and MT 2 of the IAB node C will each send two different second messages in response to the respective received first message.

The protocol stack adaptation layer shown in fig. 6 is located above the RLC layer, the RLC layer on the IAB node C is complete in function, and each node in the architecture can adopt a hop-by-hop ARQ mode. And fig. 7 is similar to fig. 6 except that the adaptation layer is located between the RLC layer and the MAC layer. In the protocol stack architecture shown in fig. 7, for the radio bearer in the Acknowledged Mode (AM) of the MT at the IAB node C, when an ARQ (automatic repeat request) in the end-to-end (E2E) mode is adopted, the ARQ-related functions are configured only on the RLC entities at the two ends (i.e., the RLC entities at the MT1 and MT 2 and the RLC entity at the host DU), and the RLC layers of the middle IAB nodes (e.g., IAB node a and IAB node B) have the segmentation (segmentation) or re-segmentation (re-segmentation) functions, and do not have the ARQ-related functions. Wherein segmentation is for one complete RLC SDU and re-segmentation is for one RLC SDU segment (segment).

Optionally, the intermediate IAB node (e.g., IAB node a and IAB node B) may further have a reassembling (reassembling) capability, for example, when transmitting a data packet carried in an Unacknowledged Mode (UM) mode, the intermediate IAB node may be further configured to reassemble the RLC SDU segments to recover the complete RLC SDU, so that, for some data packets that cannot recover the complete RLC SDU, the intermediate IAB node may discard them in advance, and avoid transmission resource waste caused by continuous transmission of a subsequent link.

The control plane protocol stack architectures shown in fig. 6 and fig. 7 have the following features: corresponding to an F1AP entity of the DU part of the IAB node C, MT1 and MT 2 have two separate PDCP entities available to carry Protocol Data Units (PDUs) of the F1 AP.

Therefore, in this case, for the sending node (e.g., IAB node C in uplink, host node in downlink or CU-CP in host node, etc.), the F1AP protocol layer above it needs to have a routing function for determining whether the F1AP PDU is sent via MT1 or MT 2, and determining that the routed F1AP PDU will be delivered to the PDCP entity corresponding to the selected MT unit to continue the processing at the sending side.

Illustratively, in the F1AP message of the F1-C (F1-control plane) interface between the CU and the homed DU of the homed node, the following information needs to be carried: an identity of IAB node C (e.g., an identity of MT1 or an identity of MT 2 or an identity of a DU of IAB node C), and a bearer identity of MT1 or MT 2 (e.g., an ID of a bearer). As such, for uplink control plane message transmission, the CU-CP may deliver the received PDCP PDUs to the corresponding PDCP entity. For downlink control plane message transmission, the host DU may add the above information to the header information of the adaptation layer of the downlink packet, and transmit the information to the IAB node C via an appropriate next-hop IAB node (IAB node a or IAB node B).

For a receiving node (e.g., an IAB node C for downlink, a donor node for uplink or a CU-CP in a donor node, etc.), an F1AP protocol layer thereon is configured with two PDCP entities corresponding thereto, and the F1AP protocol layer of the receiving node may also have the capability of ordering F1AP messages (F1AP PDUs) submitted by the PDCP entities on two paths, so that the F1AP layer may process in order the F1AP messages received from the transmitting node. Illustratively, the sorting of the receiving node may be performed according to identification information carried in the F1AP PDU, which may be information such as sequence number or time information (e.g., generation time, latest expiration time, etc.), which may be added in the F1AP PDU by the F1AP layer of the transmitting side.

Alternatively, if considering increasing the reliability of F1AP message transmission, the backhaul multi-connection capable IAB node C is configured to transmit repeated (duplicated) F1AP messages over multiple backhaul paths, then the F1AP layer of the sending node needs to have the capability of packet duplication. Accordingly, the peer F1AP layer at the receiving node needs to have duplicate detection capability, and if the receiving node receives two or more identical F1AP PDUs, the receiving node may process only one of the F1AP PDUs and discard the other F1AP PDU.

It should be understood that the embodiment of the present application only uses the F1AP layer as an example, in other possible implementations, the above-mentioned function of performing routing on the F1AP PDU, the function of adding identification information, the function of duplicate detection, and the like may also be performed by other newly added protocol layers, for example, an additional layer located between the F1AP layer and the PDCP layer, which is not limited in this application.

In addition, the F1AP message (including the uplink F1AP message and the downlink F1AP message) of the IAB node C may be transmitted to the respective parent node through the radio bearers of the MT1 and the MT 2. The radio bearer may be a Data Radio Bearer (DRB) or a Signaling Radio Bearer (SRB). It should be noted that the protocol stacks shown in fig. 6 and 7 are protocol stacks transmitted through SRBs.

Considering that the MT part of the IAB node C also has a control plane RRC layer, for the IAB node C, the RRC message of the MT and the F1AP message of the DU part thereof may multiplex transmission of a certain SRB (or an RLC bearer corresponding to the SRB, or an RLC channel, or a logical channel) of the MT, so that, in order to facilitate the PDCP entity of the receiving node to distinguish whether the received PDCP PDU is an F1AP message or an RRC message, the sending node needs to carry a message type indication (i.e., the indication information in the method 200) in the PDCP PDU, for example, the sending node may carry a message type indication in the header of the PDCP PDU, where the message type indication takes a value of x when the PDCP SDU is an F1AP message, and takes a value of y when the PDCP SDU is an RRC message, which is not limited in this embodiment of the present application.

Fig. 8 shows a schematic diagram of a multi-MT based user plane protocol stack. The UE1 comprises a service data application protocol SDAP layer, a packet data convergence protocol PDCP layer, a radio link control RLC layer, a media access control MAC layer and a physical PHY layer. Wherein the donor node includes a protocol layer that is peered to the PDCP layer and the SDAP layer of the UE 1. The donor node shown in fig. 8 is in a CU-DU separation form, and the protocol layers that are equivalent to the PDCP layer and the SDAP layer of the UE1 are located on the donor CU of the donor node. Alternatively, when the host CU is in a form of User Plane (UP) and Control Plane (CP) separation, a protocol layer peering to the PDCP layer and the SDAP layer of the UE1 is located on the CU-UP of the host node.

Since the host node is in a form where the CU and the DU are separated, the CU and the host DU are connected through an F1-U (F1-user plane) interface, and a user plane Protocol of the F1-U interface includes a GPRS Tunneling Protocol (GTP) layer, a user data packet Protocol (UDP) layer, an Internet Protocol (IP) layer, an L2 layer, and an L1 layer, where the L1 layer and the L2 layer generally refer to Protocol layers for wired communication, and depend on a connection technology specifically adopted between the host DU and the CU, for example, the L1 layer may be a physical layer, the L2 layer may be a data link layer, and the L2 layer may further include: a MAC layer, a logical link control layer (LLC), a point-to-point protocol (PPP) layer, and a link layer of Ethernet (Ethernet) technology. The specific protocol layers included in the L1 layer and the L2 layer are not limited in the embodiments of the present application.

The protocol stack adaptation layer shown in fig. 8 is located above the RLC layer, for uplink transmission, user data can be processed by the protocol layer (including the adaptation layer, the RLC layer, the MAC layer, and the PHY layer) on the backhaul link transmitting side of MT1 or MT 2 and then transmitted to the corresponding parent node, after the user data is processed by the routing function module in the adaptation layer, the backhaul link of MT1 or MT 2 is selected for transmission, and then, corresponding to MT1 and MT 2, there are two quality of service (QoS) mapping function modules, respectively, which are mainly used to determine the radio bearer (or RLC bearer, or RLC channel, or logical channel LCH) of the backhaul link transmitting the user data. After the QoS mapping process, the IAB node C selects an RLC channel or an RLC bearer for carrying user data, and then transfers the uplink data packet to a lower layer module (for the RLC layer, the MAC layer, and the PHY layer shown in fig. 8) of the corresponding MT to be processed, and then sends the uplink data packet to the corresponding parent node (IAB node a or IAB node B). Fig. 9 is similar to fig. 8, except that the adaptation layer is located between the RLC layer and the MAC layer, and is not described here again.

Alternatively, in fig. 8, the routing function module of the adaptation layer of the IAB node C is common to the MT1 and the MT 2, in other words, the adaptation layer of the MT1 or the MT 2 has the routing function module, and the MT1 and the MT 2 share the routing function module for routing.

Under the multi-connection protocol architecture shown in fig. 8, one UE carries a corresponding data packet, and at the IAB node C, the data packet can be transmitted only through the backhaul connection of a preferred MT (MT 1 or MT 2), or can be transmitted through the backhaul connections of two MTs. For example, the IAB node C may decide by itself which MT to transmit through, or may be configured by the anchor node (or anchor CU or CU-CP) for the IAB node C, and the anchor node (or anchor CU or CU-CP) may configure the IAB node C by sending an RRC message or an F1AP message, which is not limited in this embodiment.

Therefore, when the IAB node C needs to transmit the data packets carried by the same UE through the MT1 and the MT 2, for the protocol architecture shown in fig. 8, the adaptation layers of the MT1 and the MT 2 at the IAB node C may be independent (i.e. all functions of the two adaptation layer entities are independent from each other), or the routing part functions of the adaptation layers of the two MTs are common, and the functions of the QoS mapping part are located on the MT1 and the MT 2, respectively. For the protocol architecture shown in fig. 9, the backhaul link protocol layers (including RLC layer, adaptation layer, MAC layer, and PHY layer) of MT1 and MT 2 at IAB node C are independent of each other, or the RLC layer and the routing portion of the adaptation layer of MT1 and MT 2 are common, and the QoS mapping portion functions of the adaptation layer are located on MT1 and MT 2, respectively.

Furthermore, at the home node, if the home node is connected to IAB node a and IAB node B via two home DUs, respectively, an F1-U connection may be established between the two home DUs and CU-UP, respectively, i.e. corresponding to a radio bearer or PDCP entity of a certain UE, two GTP tunnels are maintained between the home CU (or CU-UP) and the two home DUs, respectively. For uplink reception, the host CU or CU-UP forwards the data packets received from both GTP tunnels to the same PDCP entity for processing. If the host node is connected with the IAB node A and the IAB node B through a host DU, corresponding to a radio bearer or a PDCP entity of a certain UE, a GTP tunnel of an F1-U interface can be established between the host DU and the CU-UP, and the host DU transmits data packets of the UE radio bearer received from the IAB node A and the IAB node B to the CU or the CU-UP through the GTP tunnel of the F1-U interface and then is delivered to the PDCP entity corresponding to the UE radio bearer by the CU or the CU-UP for processing.

Optionally, if the donor node is connected to the IAB node a and the IAB node B through a host DU, and the same UE bearer needs to be transmitted through two paths, namely, an IAB node C (MT 1) -IAB node a-host DU and an IAB node C (MT 2) -IAB node B-host DU, for the protocol architecture diagram shown in fig. 8, two adaptation layers at the host DU facing the IAB node a and the IAB node B may be independent of each other, or a routing portion function of the two adaptation layers may be common, and a function of the QoS mapping portion is located on two independent modules corresponding to the IAB node a and the IAB node B, respectively. For the protocol architecture shown in fig. 9, the protocol layers (including RLC layer, adaptation layer, MAC layer, and PHY layer) of the backhaul links facing the IAB node a and the IAB node B at the home DU are independent from each other, or the RLC layer facing the IAB node a and the IAB node B and the routing portion of the adaptation layer at the home DU are common, and the QoS mapping portion function, MAC layer, and PHY layer of the adaptation layer are respectively located on two independent modules corresponding to the IAB node a and the IAB node B.

Fig. 10-12 show networking diagrams and protocol stack diagrams of single MT based wireless backhaul network multi-connectivity according to an embodiment of the present application.

Fig. 10 is a diagram of a single MT based wireless backhaul network multiple connections. Corresponding to the communication system shown in fig. 1, UE1 is connected to a DU of IAB node C, which has two next-hop nodes, i.e., two parents, IAB node a and IAB node B on the uplink, and accesses the IAB network through IAB node C. The IAB node C includes 1 MT unit. The MT is connected to the DU of IAB node a and to the DU of IAB node B, so that the IAB node C has two independent transmission paths to the home node. Each of the IAB node a and the IAB node B includes 1 MT unit, and the IAB node a and the IAB node B are connected to the host DU of the host node through the respective MT units. The host node of fig. 10 is an access network element in which the host CU and the host DU are separate entities, and the host CU includes a CU-CP and a CU-UP.

Fig. 11 and 12 show schematic diagrams of a control plane protocol stack based on a single MT. Fig. 11 is similar to fig. 6, the adaptation layer is located above the RLC layer, fig. 12 is similar to fig. 7, the adaptation layer is located between the RLC layer and the MAC layer, and reference may be made to fig. 6 and fig. 7 for description of the protocol stack, which is not described herein again.

An F1AP entity corresponding to the DU part of the IAB node C, whose MT part has a PDCP entity capable of carrying the PDU of the F1AP, and under the PDCP entity, there may be multiple sets of lower layer protocol (including, for example, RLC layer, adaptation layer, MAC layer, PHY layer, etc.) entities corresponding to multiple parents (IAB node a and IAB node B in this embodiment).

Therefore, in this case, for the sending node (e.g., IAB node C of uplink, home node of downlink or CU-CP in home node, etc.), the PDCP layer above it needs to have a routing function for determining whether the PDCP PDU of the control plane is sent via IAB node a or IAB node B, and determining that the routed PDCP PDU will be processed to a lower protocol layer corresponding to the selected link (e.g., RLC layer, adaptation layer, MAC layer, etc., or F1AP, SCTP, IP layer, etc. of F1-C interface).

Illustratively, in the F1AP message of the F1-C interface between the CU and DU of the host node, the following information needs to be carried: an identity of the IAB node C (e.g., an identity of the MT or an identity of a DU of the IAB node C), and a bearer identity of the MT (e.g., an ID of the bearer). As such, for uplink control plane message transmission, the CU-CP may deliver the received PDCP PDUs to the corresponding PDCP entity. For downlink control plane message transmission, the host DU may add the above information to the header information of the adaptation layer of the downlink packet, and transmit the information to the IAB node C via an appropriate next-hop IAB node (IAB node a or IAB node B).

For a receiving node (e.g., IAB node C for downlink, host node for uplink or CU-CP in host node, etc.), the PDCP protocol layer above it is configured with two adaptation layer entities (corresponding to fig. 11) or RLC entities (corresponding to fig. 12) corresponding to it, and then the PDCP layer of the receiving node may also have the capability of ordering the delivered PDCP PDUs on two paths to ensure in-sequence delivery to the upper protocol layer.

Alternatively, if the reliability of the transmission of the control plane message (F1AP message of IAB node C or RRC message of IAB node C) is considered to be increased, the PDCP entity of IAB node C with backhaul multi-connection capability carrying the corresponding control plane message may be configured with the capability of packet duplication. Accordingly, the peer PDCP layer at the receiving node needs to have duplicate detection capability, and if the receiving node receives two or more identical PDCP PDUs, the receiving node can process only one PDCP PDU and discard the other PDCP PDU.

In addition, the F1AP messages (including the uplink F1AP message and the downlink F1AP message) of the IAB node C may be transmitted to the respective parent nodes through the radio bearer of the MT. The radio bearer may be a Data Radio Bearer (DRB) or a Signaling Radio Bearer (SRB). Note that the protocol stacks shown in fig. 11 and 12 are protocol stacks transmitted by SRB.

Regarding the user plane protocol stack based on single MT, the two cases can be also divided according to the location of the adaptation layer, which is similar to the user plane protocol stack based on multiple MTs shown in fig. 8 and fig. 9, and therefore, this part can refer to the related description of fig. 8 and fig. 9, and is not described again here. It should be noted that, in the user plane protocol stack based on a single MT, one MT includes two sets of backhaul link processing and transmission modules, and the transmission module includes a sending module and a receiving module.

In the embodiment of the present application, if the host node is a complete functional entity, the form of separation of the CU and the DU may not be considered, and a protocol stack between the host CU and the host DU in each protocol stack diagram is not needed, and the host node may externally reserve a protocol stack that is equivalent to the protocol stack between the IAB node and the UE 1. It should be appreciated that in actual networking, there may be many other possibilities for the scenario of a multi-connectivity architecture, for example, there may be multiple intermediate IAB nodes in one path between IAB node a and the home node, or there may be no intermediate IAB nodes. When adding or subtracting intermediate IAB nodes, the interface between IAB nodes may refer to the backhaul link protocol stack between IAB node C and IAB node a (or IAB node B), while the interface between IAB nodes and the home node may refer to the backhaul link protocol stack between IAB node a (or IAB node B) and the home node, which are not listed here.

It should be understood that the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

The data transmission method for the wireless backhaul network according to the embodiment of the present application is described in detail above with reference to fig. 1 to 12, and the data transmission apparatus for the wireless backhaul network according to the embodiment of the present application is described in detail below with reference to fig. 13 to 14.

Fig. 13 shows a data transmission apparatus 1300 for a wireless backhaul network according to an embodiment of the present application, where the apparatus 1300 may be a wireless backhaul node or a chip in the wireless backhaul node, and the apparatus 1300 may be a host node or a chip in the host node. The apparatus 1300 includes: a processing unit 1310 and a transceiver unit 1320.

In one possible implementation, the apparatus 800 is configured to execute the respective procedures and steps corresponding to the sending node in the method 200.

The processing unit 1310 is configured to: generating a first data packet; the transceiving unit 1320 is configured to: sending the first data packet to a receiving node; wherein the first data packet includes a first PDCP protocol data unit PDU generated by a first packet data convergence protocol PDCP entity, the first PDCP PDU includes a first header and a first payload, the first header includes identification information of a PDCP layer of the first PDCP PDU, the first payload includes identification information of a first protocol layer of the first payload, the first data packet further includes indication information of the first PDCP PDU, the indication information is used to indicate that a first payload in the first PDCP PDU is data of the first protocol layer, the first protocol layer corresponds to at least one PDCP entity in the apparatus, and the at least one PDCP entity includes the first PDCP entity.

Optionally, the at least one PDCP entity corresponds to at least one MT unit of the mobile terminal one to one, respectively; or, the number of the at least one PDCP entity is multiple, and multiple PDCP entities of the at least one PDCP entity correspond to one MT unit of the at least one MT unit.

Optionally, the apparatus has a plurality of next hop nodes, and the transceiver 1320 is specifically configured to: transmitting, by a first next hop node of the plurality of next hop nodes, the first data packet to the receiving node; the transceiving unit 1320 is further configured to: sending, by a second next hop node of the plurality of next hop nodes, a second data packet to the receiving node, where the second data packet includes a second PDCP PDU generated by a second PDCP entity of the at least one PDCP entity, the second PDCP PDU includes a second header and the first payload, the second header includes identification information of a PDCP layer of the second PDCP PDU, and the second data packet further includes indication information of the second PDCP PDU, and the indication information of the second PDCP PDU is used to indicate that the first payload of the second PDCP PDU is data of the first protocol layer.

Optionally, the apparatus is a wireless backhaul node, and the receiving node is a host node; or the device is a host node, and the receiving node is a wireless backhaul node.

In another possible implementation manner, the apparatus 800 is configured to execute the respective procedures and steps corresponding to the receiving node in the method 200.

The transceiving unit 1320 is configured to: receiving a first data packet from a transmitting node; the processing unit 1310 is configured to: analyzing the first data packet; the first data packet comprises a first PDCP Protocol Data Unit (PDU) generated by a first PDCP entity, the first PDCP PDU comprises a first packet header and a first load, the first packet header comprises identification information of a PDCP layer of the first PDCP PDU, the first load comprises identification information of the first protocol layer of the first load, the first data packet further comprises indication information of the first PDCP PDU, the indication information of the first PDCP PDU is used for indicating that the first load in the first PDCP PDU is data of the first protocol layer, the first protocol layer corresponds to at least one PDCP entity in the sending node, and the at least one PDCP entity comprises the first PDCP entity.

Optionally, the at least one PDCP entity corresponds to the at least one mobile terminal MT unit one to one, respectively; or, the number of the at least one PDCP entity is multiple, and multiple PDCP entities of the at least one PDCP entity correspond to one MT unit of the at least one MT unit.

Optionally, the apparatus includes a plurality of previous-hop nodes, and the transceiver 1320 is specifically configured to: receiving, by a first previous-hop node of the plurality of previous-hop nodes, the first data packet from the sending node; the transceiving unit 1320 is further configured to: receiving, by a second previous-hop node of the plurality of previous-hop nodes, a second data packet from the transmitting node, wherein the second data packet includes a second PDCP PDU generated by a second PDCP entity of the at least one PDCP entity, the second PDCP PDU includes a second header and a second payload, the second header includes identification information of a PDCP layer of the second PDCP PDU, the second payload includes identification information of a first protocol layer of the second payload, the second data packet further includes indication information of the second PDCP PDU, and the indication information of the second PDCP PDU is used to indicate that a second payload of the second PDCP PDU is data of the first protocol layer; the processing unit 1310 is further configured to: and analyzing the second data packet.

Optionally, the processing unit 1310 is further configured to: acquiring identification information of a first protocol layer of the first load and identification information of a first protocol layer of the second load; and processing the first load and the second load in sequence according to the identification information of the first protocol layer of the first load and the identification information of the first protocol layer of the second load.

Optionally, the processing unit 1310 is specifically configured to: detecting whether the identification information of the first protocol layer of the first load is the same as the identification information of the first protocol layer of the second load; and if the identification information of the first protocol layer of the first load is the same as the identification information of the first protocol layer of the second load, processing the first load or the second load.

Optionally, the sending node is a wireless backhaul node, and the apparatus is a host node; or, the sending node is a host node, and the device is a wireless backhaul node.

In another possible implementation, the apparatus 800 is configured to perform the respective procedures and steps corresponding to the host node in the method 300. The transceiver 1320 may specifically include a transmitting unit and a receiving unit.

The sending unit is used for: sending a first message to a wireless backhaul node, the first message carrying an identification of at least one packet data convergence protocol, PDCP, entity of the wireless backhaul node, the identification of the at least one PDCP entity being used for the F1application protocol, F1AP, layer of the wireless backhaul node to correspond to the at least one PDCP entity; the receiving unit is used for: receiving a second message from the wireless backhaul node, the second message indicating a configuration result of the wireless backhaul node for the first message.

Optionally, the first message is further used to indicate that data of the F1AP layer is preferentially transmitted by one of the at least one PDCP entity; or, the sending unit is further configured to: sending a third message to the wireless backhaul node, the third message indicating that data of the F1AP layer is preferentially transmitted by one of the at least one PDCP entity.

Optionally, the first message and the second message are F1AP messages; or the first message and the second message are Radio Resource Control (RRC) messages.

In another possible implementation manner, the apparatus 800 is configured to perform the respective procedures and steps corresponding to the wireless backhaul node in the method 300. The transceiver 1320 may specifically include a transmitting unit and a receiving unit.

The receiving unit is used for: receiving a first message from a host node, wherein the first message carries an identifier of at least one Packet Data Convergence Protocol (PDCP) entity of the wireless backhaul node, and the identifier of the at least one PDCP entity is used for enabling a layer F1application protocol (F1 AP) of the wireless backhaul node to correspond to the at least one PDCP entity; the sending unit is used for: and configuring according to the first message, and sending a second message to the host node, wherein the second message is used for representing the configuration result of the device on the first message.

Optionally, the first message is further used to indicate that data of the F1AP layer is preferentially transmitted by one of the at least one PDCP entity; or, the receiving unit is further configured to: and receiving a third message sent by the host node, wherein the third message is used for indicating that the data of the F1AP layer is transmitted preferentially through one PDCP entity of the at least one PDCP entity.

Optionally, the first message and the second message are F1AP messages; or, the first message and the second message are Radio Resource Control (RRC) messages.

In another possible implementation manner, the apparatus 800 is configured to execute the respective procedures and steps corresponding to the host node in the method 400. The transceiver 1320 may specifically include a transmitting unit and a receiving unit.

The sending unit is used for: sending a fourth message to a wireless backhaul node, where the fourth message carries an identifier of at least one adaptation layer entity of the wireless backhaul node, and the identifier of the at least one adaptation layer entity is used for a packet data convergence protocol PDCP entity of the wireless backhaul node to correspond to the at least one adaptation layer entity; the receiving unit is used for: receiving a fifth message from the wireless backhaul node, the fifth message indicating a configuration result of the wireless backhaul node for the first message.

Optionally, the fourth message is further used to indicate that data of the PDCP layer is preferentially transmitted by one of the at least one adaptation layer entity; the sending unit is further configured to: transmitting a sixth message to the wireless backhaul node, the sixth message indicating that data of the PDCP layer is preferentially transmitted by one of the at least one adaptation layer entity.

Optionally, the fourth message and the fifth message are F1AP messages; or, the fourth message and the fifth message are Radio Resource Control (RRC) messages.

In another possible implementation manner, the apparatus 800 is configured to perform the respective procedures and steps corresponding to the wireless backhaul node in the method 400. The transceiver 1320 may specifically include a transmitting unit and a receiving unit.

The receiving unit is used for: receiving a fourth message from a host node, where the fourth message carries an identifier of at least one adaptation layer entity of the wireless backhaul node, and the identifier of the at least one adaptation layer entity is used for a packet data convergence protocol PDCP entity of the wireless backhaul node to correspond to the at least one adaptation layer entity; the sending unit is used for: and configuring according to the fourth message, and sending a fifth message to the host node, wherein the fifth message is used for representing a configuration result of the device on the fourth message.

Optionally, the fourth message is further used to indicate that data of the PDCP layer is preferentially transmitted by one of the at least one adaptation layer entity; or, the receiving unit is further configured to: and receiving a sixth message sent by the host node, wherein the sixth message is used for indicating that the data of the PDCP layer is transmitted preferentially by one adaptation layer entity in the at least one adaptation layer entity.

It should be appreciated that the apparatus 1300 herein is embodied in the form of a functional unit. The term "unit" herein may refer to an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor (e.g., a shared, dedicated, or group processor) and memory that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable components that support the described functionality. In an alternative example, it can be understood by those skilled in the art that the apparatus 1300 can be embodied as the wireless backhaul node or the host node in the foregoing embodiments, and the apparatus 1300 can be configured to perform various processes and/or steps corresponding to the wireless backhaul node or the host node in the foregoing method embodiments, which are not described herein again to avoid repetition.

The apparatus 1300 of each of the above schemes has the function of implementing the corresponding steps executed by the wireless backhaul node or the host node in the above methods; the functions can be realized by hardware, and the functions can also be realized by executing corresponding software by hardware. The hardware or software comprises one or more modules corresponding to the functions; for example, the transmitting unit may be replaced by a transmitter, the receiving unit may be replaced by a receiver, other units, such as the determining unit, may be replaced by a processor, and the transceiving operation and the related processing operation in the respective method embodiments are respectively performed.

In the embodiment of the present application, the apparatus in fig. 13 may also be a chip or a chip system, for example: system on chip (SoC). Correspondingly, the receiving unit and the transmitting unit may be a transceiver circuit of the chip, and are not limited herein.

Fig. 14 illustrates another data transmission apparatus 1400 for a wireless backhaul network according to an embodiment of the present application. The apparatus 1400 includes a processor 1410, a transceiver 1420, and a memory 1430. Wherein the processor 1410, the transceiver 1420 and the memory 1430 are in communication with each other through the internal connection, the memory 1430 is configured to store instructions, and the processor 1410 is configured to execute the instructions stored in the memory 1430 to control the transceiver 1420 to transmit and/or receive signals.

Wherein the processor 1410 is configured to: generating a first data packet; the transceiver 1420 is configured to: sending the first data packet to a receiving node; wherein the first data packet includes a first PDCP protocol data unit PDU generated by a first packet data convergence protocol PDCP entity, the first PDCP PDU includes a first header and a first payload, the first header includes identification information of a PDCP layer of the first PDCP PDU, the first payload includes identification information of a first protocol layer of the first payload, the first data packet further includes indication information of the first PDCP PDU, the indication information is used to indicate that a first payload in the first PDCP PDU is data of the first protocol layer, the first protocol layer corresponds to at least one PDCP entity in the apparatus, and the at least one PDCP entity includes the first PDCP entity.

The transceiver 1420 is configured to: receiving a first data packet from a transmitting node; the processor 1410 is configured to: analyzing the first data packet; the first data packet comprises a first PDCP Protocol Data Unit (PDU) generated by a first PDCP entity, the first PDCP PDU comprises a first packet header and a first load, the first packet header comprises identification information of a PDCP layer of the first PDCP PDU, the first load comprises identification information of the first protocol layer of the first load, the first data packet further comprises indication information of the first PDCP PDU, the indication information of the first PDCP PDU is used for indicating that the first load in the first PDCP PDU is data of the first protocol layer, the first protocol layer corresponds to at least one PDCP entity in the sending node, and the at least one PDCP entity comprises the first PDCP entity.

In another possible implementation, the apparatus 800 is configured to perform the respective procedures and steps corresponding to the host node in the method 300.

The transceiver 1420 is configured to: sending a first message to a wireless backhaul node, where the fourth message carries an identifier of at least one adaptation layer entity of the wireless backhaul node, and the identifier of the at least one adaptation layer entity is used for a packet data convergence protocol PDCP entity of the wireless backhaul node to correspond to the at least one adaptation layer entity; receiving a second message from the wireless backhaul node, the second message indicating a configuration result of the wireless backhaul node for the first message.

In another possible implementation manner, the apparatus 800 is configured to perform the respective procedures and steps corresponding to the wireless backhaul node in the method 300.

The transceiver 1420 is configured to: receiving a first message from a host node, wherein the fourth message carries an identifier of at least one adaptation layer entity of the wireless backhaul node, and the identifier of the at least one adaptation layer entity is used for a Packet Data Convergence Protocol (PDCP) entity of the wireless backhaul node to correspond to the at least one adaptation layer entity; and configuring according to the first message, and sending a second message to the host node, wherein the second message is used for representing the configuration result of the device on the first message.

In another possible implementation manner, the apparatus 800 is configured to execute the respective procedures and steps corresponding to the host node in the method 400.

The transceiver 1420 is configured to: sending a fourth message to a wireless backhaul node, where the fourth message carries an identifier of at least one adaptation layer entity of the wireless backhaul node, and the identifier of the at least one adaptation layer entity is used for a packet data convergence protocol PDCP entity of the wireless backhaul node to correspond to the at least one adaptation layer entity; receiving a fifth message from the wireless backhaul node, the fifth message indicating a configuration result of the wireless backhaul node for the first message.

In another possible implementation manner, the apparatus 800 is configured to perform the respective procedures and steps corresponding to the wireless backhaul node in the method 400.

The transceiver 1420 is configured to: receiving a fourth message from a host node, where the fourth message carries an identifier of at least one adaptation layer entity of the wireless backhaul node, and the identifier of the at least one adaptation layer entity is used for a packet data convergence protocol PDCP entity of the wireless backhaul node to correspond to the at least one adaptation layer entity; and configuring according to the fourth message, and sending a fifth message to the host node, wherein the fifth message is used for representing a configuration result of the device on the fourth message.

It is to be understood that the apparatus 1400 may be embodied as a wireless backhaul node or a host node in the above embodiments, and may be used to perform various steps and/or procedures corresponding to the wireless backhaul node or the host node in the above method embodiments. Alternatively, the memory 1430 may include a read-only memory and a random access memory, and provides instructions and data to the processor. The portion of memory may also include non-volatile random access memory. For example, the memory may also store device type information. The processor 1410 may be configured to execute instructions stored in the memory, and when the processor 1410 executes the instructions stored in the memory, the processor 1410 is configured to perform the various steps and/or flows of the method embodiments corresponding to the wireless backhaul node or the host node described above.

It should be understood that in the embodiment of the present application, the processor of the above apparatus may be a Central Processing Unit (CPU), and the processor may also be other general processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

In implementation, the steps of the above method may be performed by integrated logic circuits of hardware in a processor or instructions in the form of software. The steps of a method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software elements in a processor. The software elements may be located in ram, flash, rom, prom, or eprom, registers, among other storage media that are well known in the art. The storage medium is located in a memory, and a processor executes instructions in the memory, in combination with hardware thereof, to perform the steps of the above-described method. To avoid repetition, it is not described in detail here.

In the present application, "at least one" means one or more, "a plurality" means two or more. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a alone, both A and B, and B alone, where A, B may be singular or plural. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of the singular or plural items. For example, at least one (one) of a, b, or c, may represent: a, b, c, a-b, a-c, b-c or a-b-c, wherein a, b and c can be single or multiple.

Those of ordinary skill in the art will appreciate that the various method steps and elements described in connection with the embodiments disclosed herein can be implemented as electronic hardware, computer software, or combinations of both, and that the steps and elements of the various embodiments have been described above generally in terms of their functionality in order to clearly illustrate the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may also be an electric, mechanical or other form of connection.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present application.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be substantially or partially contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a read-only memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

While the invention has been described with reference to specific embodiments, the scope of the invention is not limited thereto, and those skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the invention. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for data transmission in a wireless backhaul network, comprising:

a receiving node receives a first data packet from a sending node;

the receiving node analyzes the first data packet;

wherein the first data packet includes a first PDCP PDU generated by a first PDCP entity, the first PDCP PDU includes a first header and a first payload, the first header includes identification information of a PDCP layer of the first PDCP PDU, the first payload includes identification information of a first protocol layer of the first payload, the first data packet further includes indication information of the first PDCP PDU, the indication information of the first PDCP PDU is used to indicate that the first payload in the first PDCP PDU is data of the first protocol layer, the first protocol layer corresponds to at least one PDCP entity in the transmitting node, and the at least one PDCP entity includes the first PDCP entity;

wherein the receiving node has a plurality of previous hop nodes, and the receiving node receives a first data packet from a transmitting node, comprising:

the receiving node receiving the first data packet from the transmitting node through a first previous-hop node of the plurality of previous-hop nodes;

the method further comprises the following steps:

the receiving node receives a second data packet from the transmitting node through a second previous hop node of the plurality of previous hop nodes, wherein the second data packet comprises a second PDCP PDU generated by a second PDCP entity of the at least one PDCP entity, the second PDCP PDU comprises a second header and a second payload, the second header comprises identification information of a PDCP layer of the second PDCP PDU, the second payload comprises identification information of a first protocol layer of the second payload, the second data packet further comprises indication information of the second PDCP PDU, and the indication information of the second PDCP PDU is used for indicating that the second payload of the second PDCP PDU is data of the first protocol layer;

the receiving node analyzes the second data packet;

the receiving node acquires identification information of a first protocol layer of the first load and identification information of a first protocol layer of the second load;

the receiving node detects whether the identification information of the first protocol layer of the first load is the same as the identification information of the first protocol layer of the second load according to the identification information of the first protocol layer of the first load and the identification information of the first protocol layer of the second load;

if the identification information of the first protocol layer of the first payload is the same as the identification information of the first protocol layer of the second payload, the receiving node processes the first payload or the second payload.

2. The method according to claim 1, wherein the at least one PDCP entity corresponds to the at least one mobile terminal, MT, unit one to one; or

The number of the at least one PDCP entity is plural, and plural PDCP entities of the at least one PDCP entity correspond to one MT unit of the at least one MT unit.

3. A method for data transmission in a wireless backhaul network, comprising:

the host node sends a first message to the wireless backhaul node, wherein the first message carries an identifier of at least one Packet Data Convergence Protocol (PDCP) entity of the wireless backhaul node, and the identifier of the at least one PDCP entity is used for enabling a layer F1application protocol (F1 AP) of the wireless backhaul node to correspond to the at least one PDCP entity;

the host node receives a second message from the wireless backhaul node, the second message indicating a configuration result of the wireless backhaul node for the first message.

4. The method as claimed in claim 3, wherein the first message is further used for indicating that data of F1AP layer is preferentially transmitted through one of the at least one PDCP entity; or

The method further comprises the following steps:

the host node sends a third message to the wireless backhaul node, the third message indicating that data of the F1AP layer is preferentially transmitted by one of the at least one PDCP entity.

5. A method for data transmission in a wireless backhaul network, comprising:

the wireless backhaul node receiving a first message from a host node, the first message carrying an identification of at least one packet data convergence protocol, PDCP, entity of the wireless backhaul node, the identification of the at least one PDCP entity being used for a layer F1application protocol, F1AP, of the wireless backhaul node to correspond to the at least one PDCP entity;

and the wireless backhaul node configures according to the first message, and sends a second message to the host node, where the second message is used to indicate a configuration result of the wireless backhaul node on the first message.

6. The method as claimed in claim 5, wherein the first message is further used for indicating that data of F1AP layer is preferentially transmitted through one of the at least one PDCP entity; or

The method further comprises the following steps:

the wireless backhaul node receives a third message sent by the host node, where the third message is used to instruct one of the at least one PDCP entity to preferentially transmit data of the F1AP layer.

7. A method for data transmission in a wireless backhaul network, comprising:

the host node sends a fourth message to the wireless backhaul node, wherein the fourth message carries an identifier of at least one adaptation layer entity of the wireless backhaul node, and the identifier of the at least one adaptation layer entity is used for enabling a Packet Data Convergence Protocol (PDCP) entity of the wireless backhaul node to correspond to the at least one adaptation layer entity;

the host node receives a fifth message from the wireless backhaul node, the fifth message indicating a configuration result of the wireless backhaul node for the fourth message.

8. The method of claim 7, wherein the fourth message is further used for indicating that data of a PDCP layer is preferentially transmitted by one of the at least one adaptation layer entity;

the method further comprises the following steps:

the host node sends a sixth message to the wireless backhaul node, where the sixth message is used to instruct one of the at least one adaptation layer entity to preferentially transmit data of the PDCP layer.

9. A method for data transmission in a wireless backhaul network, comprising:

the wireless backhaul node receives a fourth message from a host node, where the fourth message carries an identifier of at least one adaptation layer entity of the wireless backhaul node, and the identifier of the at least one adaptation layer entity is used for a Packet Data Convergence Protocol (PDCP) entity of the wireless backhaul node to correspond to the at least one adaptation layer entity;

and the wireless backhaul node performs configuration according to the fourth message, and sends a fifth message to the host node, where the fifth message is used to indicate a configuration result of the wireless backhaul node on the fourth message.

10. The method of claim 9, wherein the fourth message is further used for indicating that data of the PDCP layer is preferentially transmitted by one of the at least one adaptation layer entity; or

The method further comprises the following steps:

and the wireless backhaul node receives a sixth message sent by the host node, where the sixth message is used to instruct one of the at least one adaptation layer entity to preferentially transmit data of the PDCP layer.

11. A data transmission apparatus for a wireless backhaul network, comprising:

a transceiving unit for receiving a first data packet from a transmitting node;

the processing unit is used for analyzing the first data packet;

the apparatus has a plurality of previous-hop nodes, and the transceiver unit is specifically configured to:

receiving, by a first previous-hop node of the plurality of previous-hop nodes, the first data packet from the sending node;

the transceiver unit is further configured to:

receiving, by a second previous-hop node of the plurality of previous-hop nodes, a second data packet from the transmitting node, wherein the second data packet includes a second PDCP PDU generated by a second PDCP entity of the at least one PDCP entity, the second PDCP PDU includes a second header and a second payload, the second header includes identification information of a PDCP layer of the second PDCP PDU, the second payload includes identification information of a first protocol layer of the second payload, the second data packet further includes indication information of the second PDCP PDU, and the indication information of the second PDCP PDU is used to indicate that the second payload of the second PDCP PDU is data of the first protocol layer;

the processing unit is further to:

parsing the second data packet;

acquiring identification information of a first protocol layer of the first load and identification information of a first protocol layer of the second load;

according to the identification information of the first protocol layer of the first payload and the identification information of the first protocol layer of the second payload, the processing unit is specifically configured to:

detecting whether the identification information of the first protocol layer of the first load is the same as the identification information of the first protocol layer of the second load;

and if the identification information of the first protocol layer of the first load is the same as the identification information of the first protocol layer of the second load, processing the first load or the second load.

12. The apparatus of claim 11, wherein the at least one PDCP entity corresponds to the at least one MT unit, respectively; or

13. A data transmission apparatus for a wireless backhaul network, comprising:

a sending unit, configured to send a first message to a wireless backhaul node, where the first message carries an identifier of at least one PDCP entity of the wireless backhaul node, and the identifier of the at least one PDCP entity is used for a layer F1application protocol F1AP of the wireless backhaul node to correspond to the at least one PDCP entity;

a receiving unit, configured to receive a second message from the wireless backhaul node, where the second message is used to indicate a configuration result of the wireless backhaul node on the first message.

14. The apparatus of claim 13, wherein the first message is further configured to indicate that data of a F1AP layer is preferentially transmitted through one of the at least one PDCP entity; or

The sending unit is further configured to:

sending a third message to the wireless backhaul node, the third message indicating that data of the F1AP layer is preferentially transmitted by one of the at least one PDCP entity.

15. A data transmission apparatus for a wireless backhaul network, comprising:

a receiving unit, configured to receive a first message from a host node, where the first message carries an identifier of at least one PDCP entity of a wireless backhaul node, and the identifier of the at least one PDCP entity is used for a layer F1application protocol F1AP of the wireless backhaul node to correspond to the at least one PDCP entity;

a sending unit, configured to perform configuration according to the first message, and send a second message to the host node, where the second message is used to indicate a configuration result of the device on the first message.

16. The apparatus of claim 15, wherein the first message is further configured to indicate that data of a F1AP layer is preferentially transmitted through one of the at least one PDCP entity; or

The receiving unit is further configured to:

and receiving a third message sent by the host node, wherein the third message is used for indicating that the data of the F1AP layer is transmitted preferentially through one PDCP entity of the at least one PDCP entity.

17. A data transmission apparatus for a wireless backhaul network, comprising:

a sending unit, configured to send a fourth message to a wireless backhaul node, where the fourth message carries an identifier of at least one adaptation layer entity of the wireless backhaul node, and the identifier of the at least one adaptation layer entity is used for a packet data convergence protocol PDCP entity of the wireless backhaul node to correspond to the at least one adaptation layer entity;

a receiving unit, configured to receive a fifth message from the wireless backhaul node, where the fifth message is used to indicate a configuration result of the wireless backhaul node on the fourth message.

18. The apparatus of claim 17, wherein the fourth message is further configured to indicate that data of a PDCP layer is preferentially transmitted by one of the at least one adaptation layer entity;

the sending unit is further configured to:

transmitting a sixth message to the wireless backhaul node, the sixth message indicating that data of the PDCP layer is preferentially transmitted by one of the at least one adaptation layer entity.

19. A data transmission apparatus for a wireless backhaul network, comprising:

a receiving unit, configured to receive a fourth message from a host node, where the fourth message carries an identifier of at least one adaptation layer entity of a wireless backhaul node, and the identifier of the at least one adaptation layer entity is used for a packet data convergence protocol PDCP entity of the wireless backhaul node to correspond to the at least one adaptation layer entity;

a sending unit, configured to send a fifth message to the host node according to the fourth message, where the fifth message is used to indicate a configuration result of the device on the fourth message.

20. The apparatus of claim 19, wherein the fourth message is further configured to indicate that data of a PDCP layer is preferentially transmitted by one of the at least one adaptation layer entity; or

The receiving unit is further configured to:

and receiving a sixth message sent by the host node, wherein the sixth message is used for indicating that the data of the PDCP layer is transmitted preferentially by one adaptation layer entity in the at least one adaptation layer entity.