WO2021031044A1

WO2021031044A1 - Iab node access method, iab node, and communication system

Info

Publication number: WO2021031044A1
Application number: PCT/CN2019/101221
Authority: WO
Inventors: 卓义斌; 朱元萍; 刘菁; 戴明增
Original assignee: 华为技术有限公司
Priority date: 2019-08-16
Filing date: 2019-08-16
Publication date: 2021-02-25

Abstract

Embodiments of the present application provide an IAB node access method, an IAB node, and a communication system, wherein the IAB node access method comprises: an IAB node determining to initiate a cell redirection or a radio resource control (RRC) re-establishment; and the IAB node selecting a cell from at least one cell supporting IABs, and initiating the cell redirection or the RRC re-establishment. In an application scenario in which an IAB node determines to initiate a cell redirection or an RRC re-establishment, cell selection is made from at least one cell supporting IABs, so as to ensure that the IAB node, when initiating a cell redirection or an RRC re-establishment, can quickly access a cell supporting IABs, thus reducing access delays.

Description

Access method of IAB node, IAB node and communication system

Technical field

The embodiments of the present application relate to the field of communication technologies, and in particular to an access method for accessing an integrated access and backhaul (IAB) node, an IAB node, and a communication system.

Background technique

The fifth-generation mobile communication (5G) network requires wider coverage, higher capacity and lower latency. In order to meet the above requirements, high-frequency small stations can be intensively deployed. However, the cost of providing optical fiber backhaul for these large numbers of densely deployed small stations is high, and the construction is difficult. The IAB technology uses wireless transmission schemes on both the Access Link and Backhaul Link, avoiding the deployment of optical fibers.

In the IAB network, an IAB node (IAB node) is also called a relay node (RN) or a wireless backhaul node. It can provide wireless access services for user equipment (UE). Data can be transmitted by at least one IAB node connected to a donor base station (donor gNodeB, DgNB) through a wireless backhaul link.

When a new IAB node needs to enter the network, or an IAB node that has already connected to the network needs to re-select a parent node for access, if you choose arbitrarily among all the cells or choose a cell on a certain frequency point, Access, the accessed cell may not be able to provide backhaul services for IAB nodes. If you access a parent node that cannot provide backhaul services for IAB nodes, it will cause the IAB node to fail to access or need to reselect the parent node Performing access further leads to prolonging the time delay of IAB node access.

Summary of the invention

The embodiments of the present application provide an access method of an IAB node, an IAB node, and a communication system, which shorten the access delay of the IAB node.

In the first aspect, an embodiment of the present application provides an access method for an IAB node, including: the IAB node determines to initiate cell redirection or RRC re-establishment. The IAB node selects a cell from at least one cell that supports IAB to initiate cell redirection or RRC re-establishment.

Through the IAB node access method provided in the first aspect, in the application scenario where the IAB node determines to initiate cell redirection or RRC re-establishment, by selecting a cell from at least one cell that supports IAB, it is ensured that the IAB node initiates cell redirection Or when RRC is re-established, it can quickly access a cell that supports IAB, which shortens the access delay.

Optionally, in a possible implementation manner of the first aspect, the IAB node determining to initiate cell redirection includes: the IAB node receives an RRC release message sent by the first IAB host and determines to initiate cell redirection. The RRC release message includes at least one cell that supports IAB.

Optionally, in a possible implementation manner of the first aspect, the IAB node determining to initiate cell redirection includes: the IAB node receives an RRC reconfiguration message sent by the first IAB host, and the RRC reconfiguration message includes at least one supporting IAB Of the cell. The IAB node receives the RRC release message sent by the first IAB host and determines to initiate cell redirection.

Optionally, in a possible implementation manner of the first aspect, the IAB node determining to initiate cell redirection includes: the IAB node receives an RRC rejection message sent by the first IAB host and determines to initiate cell redirection. The RRC rejection message includes at least one cell that supports IAB.

Optionally, in a possible implementation manner of the first aspect, the IAB node determining to initiate RRC re-establishment includes: the IAB node obtains at least one IAB-supporting cell from the first IAB host or OAM. The IAB node detects the radio link failure and determines to initiate RRC re-establishment. Or, the IAB node receives the radio link failure notification and determines to initiate RRC re-establishment.

Optionally, in a possible implementation manner of the first aspect, the IAB node selects a cell from at least one cell supporting IAB to initiate RRC re-establishment, including: the IAB node obtains a first timer, and the first timer is used to indicate The IAB node selects the effective time range for the cell to initiate RRC re-establishment according to at least one cell that supports IAB. The IAB node selects a cell from at least one cell that supports IAB to initiate RRC re-establishment within the valid time range indicated by the first timer.

Optionally, in a possible implementation manner of the first aspect, if the IAB node fails to perform RRC re-establishment, the method further includes: the IAB node selects a cell from at least one cell under the first IAB host. The IAB node initiates an RRC re-establishment to a cell selected from at least one cell under the first IAB host.

Optionally, in a possible implementation manner of the first aspect, the IAB node initiates RRC re-establishment to a cell selected from at least one cell under the first IAB host, including: the IAB node obtains the second timer, and the second The timer is used to indicate the effective time range during which the IAB node selects a cell to initiate RRC re-establishment according to at least one cell under the first IAB host. The IAB node initiates RRC re-establishment to a cell selected from at least one cell under the home of the first IAB within the valid time range indicated by the second timer.

Optionally, in a possible implementation manner of the first aspect, if the IAB node fails to perform RRC re-establishment, it further includes: the IAB node selects any accessible cell. The IAB node initiates RRC re-establishment to any accessible cell.

Optionally, in a possible implementation of the first aspect, it further includes: in the process of the IAB node initiating cell redirection or RRC re-establishment, the IAB node connects to the selected cell or the second IAB connected to the selected cell The host sends first information, and the first information is used to notify the second IAB host IAB node to support IAB.

In the second aspect, an embodiment of the present application provides an IAB node, including: a determining module, configured to determine to initiate cell redirection or RRC re-establishment. The processing module is used to select a cell from at least one cell supporting IAB to initiate cell redirection or RRC re-establishment.

Optionally, in a possible implementation of the second aspect, the determining module is specifically configured to: receive the RRC release message sent by the first IAB host and determine to initiate cell redirection. The RRC release message includes at least one cell that supports IAB.

Optionally, in a possible implementation manner of the second aspect, the determining module is specifically configured to receive an RRC reconfiguration message sent by the first IAB donor, where the RRC reconfiguration message includes at least one cell supporting IAB. Receive the RRC release message sent by the first IAB host and determine to initiate cell redirection.

Optionally, in a possible implementation of the second aspect, the determining module is specifically configured to receive the RRC rejection message sent by the first IAB host and determine to initiate cell redirection. The RRC rejection message includes at least one cell that supports IAB.

Optionally, in a possible implementation manner of the second aspect, the determining module is specifically configured to obtain at least one IAB-supporting cell from the first IAB host or OAM. Detect the radio link failure and determine to initiate RRC re-establishment. Or, receiving a radio link failure notification and determining to initiate RRC re-establishment.

Optionally, in a possible implementation manner of the second aspect, the processing module is specifically configured to: obtain a first timer, where the first timer is used to instruct the IAB node to select a cell to initiate RRC re-establishment according to at least one cell that supports IAB The effective time range. Within the valid time range indicated by the first timer, select a cell from at least one cell that supports IAB to initiate RRC re-establishment.

Optionally, in a possible implementation manner of the second aspect, if the IAB node fails to perform RRC re-establishment, the processing module is further configured to select a cell from at least one cell under the first IAB host. Initiate RRC re-establishment to a cell selected from at least one cell under the first IAB host.

Optionally, in a possible implementation manner of the second aspect, the processing module is specifically configured to: obtain a second timer, and the second timer is used to instruct the IAB node to select a cell based on at least one cell hosted by the first IAB The effective time range for RRC re-establishment. Within the valid time range indicated by the second timer, initiate RRC re-establishment to a cell selected from at least one cell under the home of the first IAB.

Optionally, in a possible implementation manner of the second aspect, if the IAB node fails to perform RRC re-establishment, the processing module is further configured to select any accessible cell. Initiate RRC re-establishment to any accessible cell.

Optionally, in a possible implementation manner of the second aspect, a sending module is further included, and the sending module is used to send a message to the selected cell or the selected cell during the process of initiating cell redirection or RRC re-establishment by the IAB node The connected second IAB host sends first information, and the first information is used to notify the second IAB host IAB node to support IAB.

In a third aspect, an embodiment of the present application provides an IAB node, which is characterized by including a processor and a transceiver. The transceiver is used to communicate with other devices, and the processor is used to execute instructions to enable the IAB node to implement the IAB node access method provided in the foregoing first aspect and any one of the implementation manners of the first aspect.

In a fourth aspect, an embodiment of the present application provides a chip, which is characterized by including a processor and a transceiver. The transceiver is used to communicate with other devices, and the processor is used to execute instructions to enable the chip to implement the IAB node access method provided in the foregoing first aspect and any one of the implementation manners of the first aspect.

In a fifth aspect, an embodiment of the present application provides a method for accessing an IAB node, including: the IAB host sends a message to the IAB node. The IAB node determines to initiate cell redirection or radio resource control RRC re-establishment according to the message. The IAB node selects a cell from at least one cell that supports IAB to initiate cell redirection or RRC re-establishment.

Optionally, in a possible implementation manner of the fifth aspect, the IAB host sending a message to the IAB node includes: the IAB host sends an RRC release message to the IAB node, and the RRC release message includes at least one cell that supports IAB.

Optionally, in a possible implementation manner of the fifth aspect, the IAB host sending a message to the IAB node includes: the IAB host sends an RRC reconfiguration message to the IAB node, and the RRC reconfiguration message includes at least one cell that supports IAB. The IAB host sends an RRC release message to the IAB node.

Optionally, in a possible implementation manner of the fifth aspect, the IAB host sending a message to the IAB node includes: the IAB host sends an RRC rejection message to the IAB node, and the RRC rejection message includes at least one cell that supports IAB.

Optionally, in a possible implementation manner of the fifth aspect, the IAB host sends a message to the IAB node, including: the IAB host notifies the IAB node of at least one cell that supports IAB. The IAB host sends a radio link failure notification to the IAB node.

In a sixth aspect, an embodiment of the present application provides a communication system, including: an IAB node and an IAB host. IAB host, used to send messages to the IAB node. The IAB node is used to determine to initiate cell redirection or radio resource control RRC re-establishment according to the message. The IAB node is also used to select a cell from at least one cell that supports IAB to initiate cell redirection or RRC re-establishment.

In a seventh aspect, an embodiment of the present application provides a readable storage medium that stores computer-executable instructions. When the computer-executed instructions are executed by a processor, the IAB as provided in the first aspect and any one of the first aspect is implemented. The access method of the node, or the access method of the IAB node provided by any one of the fifth aspect and the fifth aspect.

In an eighth aspect, embodiments of the present application provide a program product. The program product includes a computer program (that is, an execution instruction), and the computer program is stored in a readable storage medium. When the computer program is read and executed by at least one processor, the at least one processor can implement the IAB node access method provided by any one of the above-mentioned first aspect and the first aspect, or implement the above-mentioned fifth aspect And an IAB node access method provided by any implementation manner of the fifth aspect.

In the foregoing aspects and any of the embodiments of each aspect, the first IAB host is an IAB host to which the IAB node is connected.

Description of the drawings

FIG. 1 is an architecture diagram of a communication system to which an embodiment of this application is applicable;

FIG. 2 is a schematic structural diagram of a donor base station to which an embodiment of this application is applicable;

FIG. 3 is a schematic structural diagram of another donor base station applicable to an embodiment of this application;

FIG. 4 is a flowchart of an IAB node access method provided by an embodiment of the application;

Figure 5 is a message interaction diagram of another IAB node access method provided by an embodiment of the application;

FIG. 6 is a message interaction diagram of another method for accessing an IAB node provided by an embodiment of this application;

FIG. 7 is a message interaction diagram of another method for accessing an IAB node provided by an embodiment of this application;

FIG. 8 is a message interaction diagram of another IAB node access method provided by an embodiment of the application;

FIG. 9 is a flowchart of a random access method for an IAB node according to an embodiment of the application;

FIG. 10 is a message interaction diagram for an IAB node to initiate random access according to an embodiment of this application;

FIG. 11 is a schematic structural diagram of an IAB node provided by an embodiment of this application;

FIG. 12 is a schematic diagram of another structure of an IAB node provided by an embodiment of the application.

detailed description

The embodiments of the present application are described below in conjunction with the drawings.

Please refer to FIG. 1, which is an architecture diagram of a communication system provided by an embodiment of this application. The embodiment of this application does not limit the name of the communication system. For example, the communication system may also be referred to as an IAB system or an IAB network. As shown in Figure 1, the communication system may include terminal equipment, IAB nodes, and donor base stations. It should be noted that the embodiments of this application do not limit the number and names of terminal devices, IAB nodes, and donor base stations. Exemplarily, in FIG. 1, there are two terminal devices, which are marked as terminal device 1 and terminal device 2 respectively. There are 5 IAB nodes, which are marked as IAB node 1 to IAB node 5. There is one donor base station.

Optionally, the communication system may also include other devices. For example, the communication system may also include core network equipment (not shown in FIG. 1). The donor base station can be connected to the core network equipment in a wireless or wired manner. The core network equipment and the donor base station can be separate and different physical equipment, or the functions of the core network equipment and the donor base station can be integrated on the same physical equipment, or a part of the physical equipment that integrates the core network equipment Functions and some functions of the donor base station.

The following describes each communication device.

(1) IAB node

The IAB node can also be called a relay node (RN) or a wireless backhaul node or a wireless backhaul device, etc., which can provide wireless access services for terminal devices, and can also provide a wireless backhaul function for its child nodes. The terminal equipment located in the coverage area of the IAB node can communicate with the IAB node wirelessly. The terminal device is connected to the donor base station by one or more IAB nodes through a wireless backhaul link. Specifically, the uplink data packet sent by the terminal device can be transmitted to the donor base station through one or more IAB nodes, and then sent by the donor base station to the mobile gateway device, for example, the user plane function (UPF) in the 5G core network. ). The downlink data packet received by the donor base station from the mobile gateway device may be sent to the terminal device through one or more IAB nodes.

On a transmission path between the terminal equipment and the donor base station, the terminal equipment, the IAB node, and the donor base station have a certain hierarchical relationship. Each IAB node may refer to the node providing the backhaul service as the parent node, and correspondingly, each IAB node may be referred to as the child node of its parent node. The parent node of the IAB node may be another IAB node or a donor base station, and the child node of the IAB node may be another IAB node or the aforementioned terminal device in this application.

Optionally, the IAB node may include: a mobile terminal part (mobile termination, MT) and a distributed unit part (distributed unit, DU). When an IAB node faces its parent node, the IAB node can be regarded as an MT. The function of the MT is similar to the above-mentioned terminal equipment in this application. When an IAB node faces its child nodes, the IAB node can be regarded as a DU and provides wireless backhaul services for its child nodes. It should be noted that this embodiment does not limit the number of parent nodes and child nodes of the IAB node.

Optionally, an F1 interface can be established between the DU of the IAB node and the CU of the donor base station, and an F1-AP message can be transmitted, which is a control plane message of the interface between the donor CU and the IAB DU. In a possible IAB scenario, the CU is a part of the host node, and the DU is a part of the IAB node. There may be a communication interface between the CU and the DU of the IAB node, that is, the F1 interface (or F1* interface). The F1 interface contains User plane and control plane. The application protocol layer of the control plane is the F1AP (F1 application Protocol) protocol layer. The control plane messages on the F1 interface between the CU and IAB nodes are called F1AP messages and can be used to manage the F1 interface. , Configure the DU of the IAB node, transmit the radio resource control (Radio Resource Control, RRC) message of the terminal, etc.

Optionally, there is an RRC connection between the MT of the IAB node and the donor base station CU, and the RRC message is transmitted. In a possible IAB scenario, the CU is a part of the host node, and the MT is a part of the IAB node, and an RRC connection can be established between the CU and the MT of the IAB node.

Optionally, in the IAB network, the IAB node supports dual connectivity (DC) or multi-connectivity. In this way, the number of parent nodes or child nodes of the IAB node may be multiple, and there may be multiple transmission paths between the terminal device and the donor base station. The IAB network supports multi-hop or multi-connection networking, which can cope with abnormal conditions that may occur on the backhaul link, such as link interruption or blockage (blockage), load fluctuations and other abnormal conditions, which improves the reliability of transmission and the network The coverage performance.

The following is an exemplary description with reference to FIG. 1.

There are two available paths for data transmission between the terminal device 1 and the donor base station. They are:

Path 1. Terminal device 1←→IAB node 4←→IAB node 3←→IAB node 1←→the donor base station.

Path 2. Terminal device 1←→IAB node 4←→IAB node 2←→IAB node 1←→Host base station.

There are three available paths for data transmission between the terminal device 2 and the donor base station. They are:

Path 3, terminal device 2←→IAB node 4←→IAB node 3←→IAB node 1←→host base station.

Path 4. Terminal device 2←→IAB node 4←→IAB node 2←→IAB node 1←→Host base station.

Path 5, terminal device 2←→IAB node 5←→IAB node 2←→IAB node 1←→host base station.

Parent node and child node of IAB node 1

The IAB node 1 has one parent node, which is specifically a donor base station. IAB node 1 has two child nodes, namely IAB node 2 and IAB node 3.

Parent node and child node of IAB node 4

IAB node 4 has two parent nodes, namely IAB node 2 and IAB node 3. There are two sub-nodes of IAB node 4, namely terminal device 1 and terminal device 2.

Parent node and child node of IAB node 5

There is one parent node of IAB node 5, specifically IAB node 2. There is one child node of IAB node 5, specifically terminal device 2.

(2) Donor base station

The donor base station may also be referred to as a donor node or IAB donor (IAB donor).

The donor base station may be an access network element with complete base station functions. For example, the terminal device is connected to a radio access network (RAN) node of the wireless network. At present, some examples of RAN nodes are: new radio access technology (NR) (or 5G) systems in the new generation of base stations (generation Node B, gNB), transmission reception point (transmission reception point, TRP) , Evolved Node B (evolved Node B, eNB), radio network controller (RNC), Node B (Node B, NB), base station controller (base station controller, BSC), base transceiver station (base transceiver station, BTS), home base station (for example, home evolved NodeB, or home Node B, HNB), baseband unit (BBU), relay station, or wireless fidelity (Wifi) access point (access point, AP) etc. The wireless coverage area of the donor base station may include one or more cells. The embodiment of this application does not limit the specific technology and specific equipment form adopted by the donor base station.

The donor base station may also be an access network element including a centralized unit (centralized unit, CU) and a distributed unit (distributed unit, DU) separated form. The donor base station can be connected to a core network device that provides services for terminal devices, and provides a wireless backhaul function for IAB nodes. For example, the core network may be a 5G core network (5GC). For another example, the core network may be a 4G core network, also referred to as an evolved packet core (EPC). In this application, the centralized unit of the donor base station may also be referred to as donor CU, donor CU or IAB CU, and the distributed unit of the donor base station may be referred to as donor DU, donor DU or IAB DU.

The communication between the donor base station and the IAB node or terminal device follows a certain protocol layer structure. For example, the control plane protocol layer structure may include the radio resource control (RRC) layer, the packet data convergence protocol (PDCP) layer, the radio link control (RLC) layer, and the media interface. Access control (media access control, MAC) layer and physical layer and other protocol layer functions. The user plane protocol layer structure can include the functions of the PDCP layer, the RLC layer, the MAC layer, and the physical layer; in one implementation, the PDCP layer can also include a service data adaptation protocol (SDAP) layer ; On the backhaul link between the host node and the IAB node, the RLC layer may also include a backhaul adaptation protocol (backhaul adaptation protocol) layer.

The functions of these protocol layers can be implemented by one node or by multiple nodes; for example, in a structure, the donor base station can include donor CU and donor DU, and multiple donor DUs can be centrally controlled by one donor CU. As shown in Figure 2, donor CU donor and DU can be divided according to the protocol layer of the wireless network. For example, the functions of the PDCP layer and above protocol layers are set in the donor CU, and the protocol layers below PDCP, such as the RLC layer and MAC layer, etc. In donor DU.

This type of protocol layer division is just an example. It can also be divided in other protocol layers. For example, in the RLC layer, the functions of the RLC layer and above protocol layers are set to donor CU, and the functions of the protocol layers below the RLC layer are set to donor. DU; or, divided in a certain protocol layer, for example, set part of the functions of the RLC layer and the functions of the protocol layer above the RLC layer in the donor CU, and set the remaining functions of the RLC layer and the functions of the protocol layer below the RLC layer in donor DU. In addition, it can also be divided in other ways, for example, by delay. The functions that need to meet the delay requirements for processing time are set in the donor DU, and the functions that do not need to meet the delay requirements are set in the donor CU.

Please continue to refer to Figure 3. Compared to the structure shown in Figure 2, the control plane (CP) and user plane (UP) of the donor CU can also be separated and implemented by dividing them into different entities, which are the control planes. CU entity (CU-CP entity) and user plane CU entity (CU-UP entity). For example, the donor CU may consist of one CU-CP and one (or more) CU-UPs.

In the above structure, the signaling generated by the donor CU can be sent to the IAB node or terminal device through the donor DU, or the signaling generated by the terminal device or IAB node can be sent to the donor CU through the donor DU. Among them, the donor DU can directly pass the protocol layer encapsulation without analyzing the signaling and transparently transmit it to the IAB node, terminal device or donor CU. In the following embodiments, if this signaling is involved in the transmission between the donor DU and the IAB node or terminal equipment, at this time, the donor DU does not analyze the signaling when sending or receiving the signaling, but directly encapsulates the signaling through the protocol layer. Transparent transmission to the target receiving node.

In the above embodiments, the CU is divided into network devices of the wireless access network. In addition, the CU may also be divided into network devices on the core network (CN) side, which is not limited here.

When the above CU-DU structure is adopted, the donor base station in each embodiment of the present application may be a donor CU node, or a donor DU node, or a device including a donor CU node and a donor DU node.

(3) Terminal equipment

Terminal equipment, also known as user equipment (UE), mobile station (MS), or mobile terminal (mobile terminal, MT), is a device that provides users with voice/data connectivity, for example, Handheld devices with wireless connection function, or vehicle-mounted devices, etc. At present, some examples of terminal devices are: mobile phones (mobile phones), tablet computers, notebook computers, handheld computers, mobile internet devices (MID), wearable devices, virtual reality (VR) devices, augmented Augmented reality (AR) equipment, wireless terminals in industrial control (industrial control), wireless terminals in self-driving (self-driving), wireless terminals in remote medical surgery, and smart grid (smart grid) The wireless terminal in the transportation safety (transportation safety), the wireless terminal in the smart city (smart city), or the wireless terminal in the smart home (smart home), etc.

It should be noted that the IAB networking scenario shown in Figure 1 is only an example. In the IAB scenario combining multi-hop and multi-connection, there are more other possibilities, for example, a donor base station and another donor base station. The following IAB nodes form dual connections to serve terminal equipment, etc., which are not listed one by one.

According to the prior art, in an application scenario, when an IAB node selects a cell for access like a terminal device, but the cell does not support IAB, the IAB node needs to be redirected to an IAB-supporting cell through the donor base station. In the district. In the process of cell redirection, the message sent by the donor base station to the IAB node may carry the redirected carrier information. The IAB node may try to search for a cell through the carrier information, and select a suitable cell for access. However, the suitable cell is not necessarily a cell that supports IAB. When the message sent by the donor base station to the IAB node does not carry the redirected carrier information, the cell that the IAB node selects to access may be any cell, and the cell may not necessarily be a cell that supports IAB. Therefore, the time delay for the IAB node to access a cell that supports IAB or access to an IAB-enabled parent node is relatively long. In another application scenario, when an IAB node that has already accessed the IAB network determines to initiate RRC re-establishment, if a suitable cell is not found within a given time, the MT part of the IAB node will enter the RRC idle state. Even if a suitable cell is found for access, the accessed cell may not necessarily support IAB, resulting in increased IAB node re-establishment delay or failure in re-establishment.

In view of this, the embodiments of the present application provide an access method for an IAB node, which can quickly access a cell that supports IAB when the IAB node initiates cell redirection or RRC re-establishment, and shortens the access delay.

The description is given below in conjunction with the drawings.

Fig. 4 is a flowchart of an IAB node access method provided by an embodiment of the application. In the method for accessing an IAB node provided in this embodiment, the executor may be an IAB node. As shown in FIG. 4, the access method of the IAB node provided in this embodiment may include:

S401: The IAB node determines to initiate cell redirection or RRC re-establishment.

Among them, the implementation manner for the IAB node to determine initiation of cell redirection or RRC re-establishment may refer to the implementation manner for terminal equipment or the IAB node to determine initiation of cell redirection or RRC re-establishment in the existing communication process, and the principles are similar. For example, when the IAB node is in the RRC connection state, if the IAB node detects that the wireless backhaul link between it and the parent node has a radio link failure (RLF) and the IAB node has only one parent node, or When the IAB node is dual-connected (with two parent nodes) and both parent nodes have RLF or the primary parent node has RLF, the IAB node will initiate an RRC re-establishment process. For example, when the donor base station decides to redirect the IAB node to a cell of another frequency point according to the inter-frequency measurement report information reported by the IAB node, the donor base station sends a cell redirection to the IAB node. The foregoing is only an example of the IAB node initiating RRC re-establishment or cell redirection, and the manner in which the IAB node initiates RRC re-establishment or cell redirection is not limited in this embodiment.

S402. The IAB node selects a cell from at least one cell that supports IAB to initiate cell redirection or RRC re-establishment.

Specifically, if the IAB node determines to initiate cell redirection, the IAB node may select a cell from at least one cell that supports IAB to initiate cell redirection. If the IAB node determines to initiate RRC re-establishment, the IAB node may select a cell from at least one cell that supports IAB to initiate RRC re-establishment. Wherein, the at least one cell that supports IAB is a cell that supports IAB that can be obtained by an IAB node.

It can be seen that the IAB node access method provided in this embodiment, in an application scenario where the IAB node determines to initiate cell redirection or RRC re-establishment, because the IAB node selects a cell among the acquired at least one cell that supports IAB, and initiates the cell Redirection or RRC re-establishment reduces the range of selectable cells. The new cell selected for access must be a cell that supports IAB. Therefore, you can quickly access an IAB-supported cell when the IAB node initiates cell redirection or RRC re-establishment. The cell shortens the access delay.

It should be noted that this embodiment does not limit the specific number and acquisition method of the at least one IAB-supporting cell, which may be different in different application scenarios.

Optionally, the identity of the cell supporting IAB can be any one of the following:

NR cell global identifier (NCGI), E-UTRAN cell global identifier (ECGI), and identification of the backhaul adaptation protocol (BAP) layer of the IAB node Information and other identification information that can uniquely identify the IAB node.

Optionally, the information of the cell supporting IAB may also include at least one of the following information: carrier frequency information of the cell, sub-carrier spacing (SCS) information, and measurement timing configuration (measurement timing configuration, MTC) information .

It should be noted that this embodiment does not limit the specific form of the acquired relevant information of at least one IAB cell. The following is an example to illustrate.

Optionally, in an implementation manner, the aforementioned related information of the at least one IAB-supporting cell may include: carrier frequency information; and at least one of the following information of the cell corresponding to each carrier frequency information: the identity of the cell , SCS information and MTC information. Exemplary, please refer to the examples shown in Table 1.

Table 1

Optionally, in another implementation manner, the above-mentioned related information of the at least one IAB-supporting cell may include: the identity of the cell; and at least one of the following information of each cell: carrier frequency information of the cell, SCS Information and MTC information. Exemplary, please refer to the examples shown in Table 2.

Table 2

NCGI 1 NCGI 1	载波频率F1Carrier frequency F1		SCS信息1SCS information 1	MTC信息1 MTC information 1
NCGI 2NCGI 2	载波频率F1Carrier frequency F1	SCS信息2SCS information 2	MTC信息2MTC information 2
NCGI 3NCGI 3	载波频率F1Carrier frequency F1	SCS信息3SCS information 3	MTC信息3MTC information 3
NCGI 4NCGI 4	载波频率F2Carrier frequency F2	SCS信息4SCS Information 4	MTC信息4MTC information 4
NCGI 5NCGI 5	载波频率F2Carrier frequency F2	SCS信息5SCS Information 5	MTC信息5MTC information 5

This embodiment provides an access method for an IAB node, including: the IAB node determines to initiate cell redirection or RRC re-establishment, and the IAB node selects a cell from at least one cell that supports IAB to initiate cell redirection or RRC re-establishment. In the application scenario where the IAB node determines to initiate cell redirection or RRC re-establishment, by selecting a cell from at least one cell that supports IAB, it is ensured that the IAB node can quickly access a cell that supports IAB when it initiates cell redirection or RRC re-establishment , Shortening the access delay.

Hereinafter, the MM provided in this application will be described in detail through the embodiments shown in FIGS. 5 to 8 in combination with different application scenarios. Among them, for the convenience of description, the cell that the IAB node initially tries to access (may support IAB or may not support IAB) or the cell that has been accessed (support IAB) may be called the first cell, and the IAB host to which the IAB node is connected It can be called the first IAB host. The IAB node determines that cell redirection or RRC re-establishment occurs, and the cell selected from at least one cell that supports IAB may be called the second cell. The IAB host connected to the second cell may be referred to as a second IAB host.

Optionally, on the basis of the embodiment shown in FIG. 4, FIG. 5 is a message interaction diagram of another IAB node access method provided in an embodiment of the application. In this embodiment, in an application scenario where the IAB node determines to initiate cell redirection, an implementation manner of the access method of the IAB node is provided. In the method for accessing an IAB node provided in this embodiment, the execution subject may involve the IAB node and the first IAB host. As shown in Figure 5, the method for accessing an IAB node provided in this embodiment may include:

S501: The first IAB host sends an RRC release message to the IAB node. Wherein, the RRC release message includes at least one cell that supports IAB.

Correspondingly, the IAB node receives the RRC release message sent by the first IAB host.

S502: The IAB node determines to initiate cell redirection.

S503. The IAB node selects a cell from at least one cell that supports IAB to initiate cell redirection.

In this embodiment, in S401, the IAB node determining to initiate cell redirection may include: the IAB node receives an RRC release message sent by the first IAB host and determines to initiate cell redirection, and the RRC release message includes at least one cell that supports IAB . That is, S501 and S502 are involved. Among them, the principles of S503 and S403 are similar and will not be repeated here.

In this embodiment, when the first IAB host determines to redirect the IAB node to a cell that supports IAB, the first IAB host may send an RRC release message to the IAB node. The RRC release message triggers the IAB node to determine to initiate cell redirection. Since the RRC release message includes at least one cell that supports IAB, the IAB node can select a cell to initiate cell redirection based on at least one cell that supports IAB carried in the RRC release message. This ensures that the selected cell must support IAB, thereby shortening the access delay in the scenario where the cell redirection is determined to be initiated.

It should be noted that this embodiment does not limit the judgment condition for the first IAB host to determine to redirect the IAB node to a cell that supports IAB. For example, the IAB node initially selects the first cell for random access, and completes the RRC connection establishment process. However, the first cell is a cell that does not support IAB. Therefore, the first IAB host determines to redirect the IAB node to a cell that supports IAB.

Optionally, the RRC release message may include a cell list, and the cell list may include the at least one cell that supports IAB.

Optionally, the cell list may include at least one of the following information: cell identity, carrier frequency information, SCS information, and MTC information. For details, please refer to the embodiment shown in FIG. 4, and the principle is similar, and will not be repeated here.

Optionally, on the basis of the embodiment shown in FIG. 4, FIG. 6 is a message interaction diagram of another method for accessing an IAB node provided by an embodiment of this application. In the application scenario where the IAB node determines to initiate cell redirection, this embodiment provides another implementation manner of the access method of the IAB node. In the method for accessing an IAB node provided in this embodiment, the execution subject may involve the IAB node and the first IAB host. As shown in Figure 6, the method for accessing an IAB node provided in this embodiment may include:

S601. The first IAB host sends a first message to the IAB node. The first message includes at least one cell supporting IAB.

Correspondingly, the IAB node receives the first message sent by the first IAB host.

Optionally, the first message may include at least one of the following: an RRC reconfiguration message and an F1-AP message.

S602: The first IAB host sends an RRC release message to the IAB node.

S603: The IAB node determines to initiate cell redirection.

S604. The IAB node selects a cell from at least one cell that supports IAB to initiate cell redirection.

In this embodiment, optionally, in S401, the IAB node determining to initiate cell redirection may include: the IAB node receives an RRC reconfiguration message sent by the first IAB host, and the RRC reconfiguration message includes at least one cell that supports IAB; The IAB node receives the RRC release message sent by the first IAB host and determines to initiate cell redirection. That is, S601 to S603 are involved. Among them, the principles of S604 and S403 are similar and will not be repeated here.

It should be noted that this embodiment does not limit the execution sequence among S601, S602, and S603. As long as S601 is executed before S604. Optionally, an execution sequence may be S601, S602, S603, and S604. Optionally, another execution order may be S602, S603, S601, and S604.

In this embodiment, when the first IAB host determines to redirect the IAB node to a cell that supports IAB, the first IAB host may send an RRC release message to the IAB node. The RRC release message triggers the IAB node to determine to initiate cell redirection. The IAB node can obtain at least one IAB-supporting cell carried in the first message by receiving the first message sent by the first IAB host. Therefore, the IAB node can select a cell to initiate cell redirection based on the obtained at least one cell that supports IAB. This ensures that the selected cell must support IAB, thereby shortening the access delay in the scenario where the cell redirection is determined to be initiated.

Optionally, the first message may include a cell list, and the cell list may include the at least one cell supporting IAB.

Optionally, the cell list may include at least one of the following information: cell identity, carrier frequency information, SCS information, and MTC information. For details, please refer to the embodiment shown in FIG. 4, the principle is similar, and details are not repeated here.

Optionally, based on the embodiment shown in FIG. 4, FIG. 7 is a message interaction diagram of another method for accessing an IAB node provided by an embodiment of the application. In the application scenario where the IAB node determines to initiate cell redirection, this embodiment provides another implementation manner of the access method of the IAB node. In the method for accessing an IAB node provided in this embodiment, the execution subject may involve the IAB node and the first IAB host. As shown in Figure 7, the method for accessing an IAB node provided in this embodiment may include:

S701: The first IAB host sends an RRC rejection message to the IAB node. Wherein, the RRC reject message includes at least one cell that supports IAB.

Correspondingly, the IAB node receives the RRC rejection message sent by the first IAB host.

S702. The IAB node determines to initiate cell redirection.

S703. The IAB node selects a cell from at least one cell that supports IAB to initiate cell redirection.

In this embodiment, in S401, the IAB node determining to initiate cell redirection may include: the IAB node receives an RRC rejection message sent by the first IAB host and determines to initiate cell redirection. The RRC rejection message includes at least one cell that supports IAB. That is, S701 and S702 are involved. Among them, the principles of S703 and S403 are similar and will not be repeated here.

In this embodiment, when the first IAB host determines to redirect the IAB node to a cell that supports IAB, the first IAB host may send an RRC rejection message to the IAB node. The RRC reject message triggers the IAB node to determine to initiate cell redirection. Since the RRC reject message includes at least one cell that supports IAB, the IAB node can select the cell to initiate cell redirection based on at least one cell that supports IAB carried in the RRC reject message. This ensures that the selected cell must support IAB, thereby shortening the access delay in the scenario where the cell redirection is determined to be initiated.

It should be noted that this embodiment does not limit the judgment condition for the first IAB host to determine to redirect the IAB node to a cell that supports IAB. For example, the IAB node initially selects the first cell for random access, and the RRC connection establishment process has not been completed. However, the first cell is a cell that does not support IAB. Therefore, the first IAB host determines to redirect the IAB node to a cell that supports IAB. Compared with the embodiment shown in FIG. 5 or FIG. 6, this embodiment does not complete the RRC connection establishment process, which further accelerates the speed of selecting a cell supporting IAB and shortens the access delay.

Optionally, the RRC rejection message may include a cell list, and the cell list may include the at least one cell that supports IAB.

Optionally, on the basis of the embodiment shown in FIG. 4, FIG. 8 is a message interaction diagram of another method for accessing an IAB node provided by an embodiment of this application. In the application scenario where the IAB node determines to initiate RRC re-establishment, this embodiment provides yet another implementation manner of the access method of the IAB node. In the method for accessing an IAB node provided in this embodiment, the execution subject may involve the IAB node and the first IAB host. Optionally, it may also involve an operation and maintenance management system (operations, administrator and maintenance, OAM). As shown in Figure 8, the method for accessing an IAB node provided in this embodiment may include:

S801: The first IAB host notifies the IAB node of at least one cell that supports IAB.

Correspondingly, the IAB node obtains at least one cell that supports IAB from the first IAB host.

S802. The OAM notifies the IAB node of at least one cell that supports IAB.

Correspondingly, the IAB node obtains at least one cell that supports IAB from OAM.

S803: The IAB node detects that the radio link fails and determines to initiate RRC re-establishment. Or, the IAB node receives the radio link failure notification and determines to initiate RRC re-establishment.

S804. The IAB node selects a cell from at least one cell that supports IAB to initiate cell redirection.

In this embodiment, optionally, in S401, the IAB node determining to initiate RRC re-establishment may include: the IAB node receiving at least one IAB-supporting cell sent by the first IAB host or OAM. The IAB node detects the radio link failure and determines to initiate RRC re-establishment, or the IAB node receives the radio link failure notification and determines to initiate RRC re-establishment. That is, S801 to S803 are involved. Among them, the principles of S804 and S403 are similar and will not be repeated here.

It should be noted that S801 and S802 can be executed at the same time, or only one of them can be executed.

It should be noted that this embodiment does not limit the execution sequence between S801 and/or S802 and S803. As long as S801 and/or S802 are executed before S804. Optionally, the execution order may be S801, S803, S804, or S803, S801, S804, or S802, S803, S804, or S803, S802, S804.

In this embodiment, when the IAB node detects a wireless link failure by itself, or receives a wireless link failure notification, it can trigger the IAB node to determine to initiate RRC re-establishment. Optionally, the IAB node may receive a radio link failure notification sent by its parent node or the first IAB host. The IAB node may receive at least one IAB-supporting cell sent by the first IAB host or OAM. Therefore, the IAB node can select a cell to initiate RRC re-establishment based on the obtained at least one cell that supports IAB. This ensures that the selected cell must support IAB, thereby shortening the access delay in the scenario where the RRC re-establishment is determined to be initiated.

Optionally, the at least one IAB-supporting cell may be carried in a cell list included in a first message sent by the first IAB host or a second message sent by OAM. Optionally, the cell list may include at least one of the following information: cell identity, carrier frequency information, SCS information, and MTC information. For details, please refer to the embodiment shown in FIG. 4, and the principle is similar, and will not be repeated here.

For the first message involved in this embodiment, reference may be made to the description of the first message in the embodiment shown in FIG. 6, and the principle is similar, and will not be repeated here.

Optionally, in S804, the IAB node selects a cell from at least one cell supporting IAB to initiate cell redirection, which may include:

The IAB node acquires a first timer, and the first timer is used to instruct the IAB node to select a cell according to at least one cell supporting IAB to initiate an effective time range for RRC re-establishment.

The IAB node selects a cell from at least one cell that supports IAB to initiate RRC re-establishment within the valid time range indicated by the first timer.

The following examples are illustrative.

Assume that the valid time range indicated by the first timer is 3 minutes. At least one cell supporting IAB includes 10 cells, which are marked as cell 1 to cell 10. Therefore, the first timer indicates that the effective time for the IAB node to initiate RRC re-establishment according to the cell selection from cell 1 to cell 10 is 3 minutes.

Optionally, in an example, the IAB node selects cell 3 to initiate RRC re-establishment, and if the RRC re-establishment is successful after 1 minute, the RRC re-establishment process is stopped.

Optionally, in another example, the IAB node selects cell 3 to initiate RRC re-establishment, and if the RRC re-establishment fails after 1 minute, it continues to select cell 2 to initiate RRC re-establishment. After 1 minute, if the RRC re-establishment is successfully initiated to cell 2, the RRC re-establishment process is stopped.

Optionally, in another example, the IAB node selects cell 3 to initiate RRC re-establishment, and if the RRC re-establishment fails after 1 minute, it continues to select cell 5 to initiate RRC re-establishment. After 1 minute, the initiation of RRC re-establishment to cell 5 fails, and cell 8 is selected to initiate RRC re-establishment. After 1 minute, the RRC re-establishment fails to be initiated to cell 8. As the 3 minutes indicated by the first timer expires, the process of RRC re-establishment is stopped.

By setting the first timer, the IAB node can prevent unlimited attempts to initiate RRC re-establishment according to at least one cell that supports IAB, avoiding continuous failure of RRC re-establishment in abnormal scenarios, and shortening the access delay.

It should be noted that this embodiment does not limit the specific value of the first timer.

Optionally, if the IAB node access method provided in this embodiment fails to perform RRC re-establishment, it may also include:

The IAB node selects a cell from at least one cell under the home of the first IAB.

The IAB node initiates an RRC re-establishment to a cell selected from at least one cell under the first IAB host.

Specifically, if the IAB node fails to perform RRC re-establishment according to at least one IAB-supporting cell obtained from the first IAB host or from OAM, it may try to select a cell from at least one cell under the first IAB host to initiate RRC re-establishment. Since the first IAB host definitely supports IAB, at least one cell under the first IAB host must support IAB. This ensures that a cell that supports IAB is selected to initiate RRC re-establishment and shortens the access delay.

Optionally, the IAB node initiating RRC re-establishment to a cell selected from at least one cell under the first IAB host may include:

The IAB node acquires a second timer, and the second timer is used to instruct the IAB node to select a cell according to at least one cell under the first IAB dormant to initiate an effective time range for RRC re-establishment.

The IAB node initiates RRC re-establishment to a cell selected from at least one cell under the home of the first IAB within the valid time range indicated by the second timer.

Specifically, the second timer is used to instruct the IAB node to select the effective time range for initiating RRC re-establishment according to at least one cell under the first IAB donor. At least one cell supporting IAB selects the effective time range for the cell to initiate RRC re-establishment. The principle is similar, and you can refer to the above description, which will not be repeated here.

It should be noted that this embodiment does not limit the specific value of the second timer.

It should be noted that, in actual applications, the IAB node can obtain at least one cell supporting IAB from the first IAB host or OAM, and can also obtain at least one cell under the first IAB host. This embodiment does not limit the priority selection sequence of the two types of cells. For example, the IAB node may first select a cell to initiate RRC re-establishment within the valid time range indicated by the second timer in at least one cell under the home of the first IAB. If the second timer expires and the RRC re-establishment is not successful, the RRC re-establishment can be initiated by selecting a cell from at least one IAB-supporting cell obtained from the first IAB host or OAM within the valid time range indicated by the first timer.

Optionally, in the IAB node access method provided in this embodiment, if the IAB node fails to perform RRC re-establishment, it may also include:

The IAB node selects any cell that can be accessed.

The IAB node initiates RRC re-establishment to any accessible cell.

Among them, any cell that can be accessed may be a cell that supports IAB, or a cell that does not support IAB. When it is a cell that does not support IAB, the IAB node access method provided in any of the implementation manners in FIGS. 5 to 8 of this application can be implemented.

The embodiment of the application also provides a random access method for an IAB node. Fig. 9 is a flowchart of a random access method for an IAB node provided by an embodiment of the application. As shown in Figure 9, the random access method for IAB nodes provided in this embodiment may include:

S901. The IAB node selects random access resources.

Optionally, the IAB node may select a random access opportunity (occasion) on any of the following random access resources and initiate random access:

Random access resource 1: The competing random access resource broadcast by the donor base station for the terminal device.

Random access resource 2: The competing random access resource broadcast by the donor base station for the IAB node.

Random access resource 3: Non-competitive random access resources configured by the donor base station for the IAB node.

In this embodiment, random access can have multiple types. The type of random access is different, and the IAB node selects random access resources in different ways.

Optionally, for a certain type of random access, if the donor base station configures the IAB node with non-competitive random access resources of this type of random access, the IAB node may select from the configured non-competitive random access resources of this type of random access. Random access opportunities are selected from competing for random access resources; if the donor base station does not configure non-competitive random access resources for this type of random access for the IAB node, the IAB node can initiate competing random access and access resources from random access Select random access opportunity from 1 or random access resource 2.

Optionally, for random access during initial access, if the donor base station broadcasts random access resource 2, regardless of whether the donor base station broadcasts random access resource 1, the IAB node can select random access from random access resource 2. Opportunity: If the donor base station only broadcasts random access resource 1, the IAB node can select random access opportunity from random access resource 1.

Optionally, for the non-competitive random access requested by the physical downlink control channel (PDCCH), if the donor base station broadcasts both random access resource 2 and random access resource 1, the IAB node can access from random access Random access opportunity is selected from resource 2; if the donor base station only broadcasts random access resource 1, the IAB node can select random access opportunity from random access resource 1. If the donor base station broadcasts the random access resource 2 and the random access resource 1 at the same time, the IAB node can select a random access opportunity from the random access resources displayed by the PDCCH to instruct the IAB node to perform random access.

Optionally, for other types of random access other than PDCCH requests, for example, random access caused by radio link failure or random access initiated based on a scheduling request (Scheduling Request, SR), etc., if the donor base station only Random access resource 1 is broadcast, then the IAB node can select random access opportunities from random access resource 1. Because some random access types have high requirements for delay, if the donor base station broadcasts random access resource 2 and random access resource 1 at the same time, the IAB node can predefine or configure a certain random access The type selects random access opportunity from random access 1 or random access 2; or, the IAB node can compare the period of the two according to the received configuration message of random access resource 2 and random access resource 1. Random access opportunities are selected from random access resources with a shorter period; alternatively, the IAB node can select the first random access opportunity among the random access resource 2 and random access resource 1 received configuration messages. Access opportunity.

Through the above random access resource selection method, the method for IAB nodes to select random access resources in the access process of various random access types is enabled, and the access delay of the competing random access process is further optimized. .

S902: The IAB node initiates random access to the parent node.

Among them, the type of random access initiated by the IAB node to the parent node may be competing random access or non-competitive random access, which is not limited in this embodiment. And the reason for the IAB node to initiate random access can be triggered by RRC re-establishment, or triggered by SR request, or triggered by PDCCH request, or random access triggered by other reasons. In this embodiment, random access is initiated The reason is not limited.

Optionally, when the IAB node initiates random access, the IAB node may send first information to its parent node, and the first information is used to notify the parent node or the donor base station to which the parent node is connected The IAB node supports IAB instead of ordinary UE.

Specifically, as described in S901, the random access resource broadcast by the donor base station for the IAB node may overlap with the random access resource broadcast for the terminal device. Therefore, the first information can clearly inform the parent node of the IAB node that it supports IAB and is not an ordinary terminal device, so as to facilitate the subsequent communication process and improve the success rate of IAB node access.

Optionally, the parent node may be a target cell or a target IAB parent node selected by the IAB node in scenarios such as re-establishment or handover or cell reselection.

The implementation of the first information will be described below in conjunction with a signaling flow of the random access process. FIG. 10 is a message interaction diagram for an IAB node to initiate random access according to an embodiment of the application, and the involved execution subject may include an IAB node, a parent node, and a donor base station. As shown in Figure 10, the IAB node initiates random access, which may include:

1. The IAB node sends a random access pilot (preamble) to the parent node. Also called message 1.

2. The parent node sends a random access response (RAR) to the IAB node. Also called message 2.

3. The IAB node sends an RRC establishment request message or an RRC reestablishment request message to the parent node. Also called message 3.

4. The parent node sends an initial uplink RRC information transfer (INITIAL UL RRC MESSAGE TRANSFER) message to the donor base station. Wherein, the initial uplink RRC information transfer message may include the message 3, and the message 3 is transparently transmitted to the donor base station.

5. The donor base station sends a downlink RRC information transfer (DL RRC MESSAGE TRANSFER) message to the parent node. Wherein, the downlink RRC information transfer message may include message 4 (see the following description), and the message 4 is transparently transmitted to the parent node.

6. The parent node sends an RRC establishment message or an RRC re-establishment message to the IAB node. Also known as message 4.

7. The IAB node sends an RRC establishment complete message or an RRC reestablishment complete message to the parent node. Also known as message 5.

8. The parent node sends an uplink RRC information transfer (UL RRC MESSAGE TRANSFER) message to the donor base station. Wherein, the uplink RRC information transfer message may include message 5, and message 5 is transparently transmitted to the donor base station.

Among them, the specific content included in each message can refer to the existing communication protocol.

Optionally, the indication mode of the first information may be any of the following:

Manner 1: Predefine one or more random access pilot (preamble) indexes for random access of the IAB node through the protocol. When the IAB node uses one of the predefined one or more random access pilot indexes to perform random access, the parent node or the donor base station connected to the parent node can determine that the IAB node supports IAB.

Method 2: If it is a competing random access type, it can be completed in message 3 (the RRC establishment request message or RRC re-establishment request message sent by the IAB node to the donor base station) or message 5 (the RRC establishment sent by the IAB node to the donor base station) The message or the RRC re-establishment complete message) carries the first information. When the parent node or the donor base station to which the parent node is connected receives the message 3 or the message 5, it can be determined that the IAB node supports IAB.

Method 3: If the donor base station broadcasts random access resource 2 and random access resource 1 at the same time, and random access resource 2 and random access resource 1 partially overlap in time and frequency, the IAB node can use random access resource 2 The random access opportunity is selected in the part that does not overlap with the random access resource 1, so that the parent node can determine that the IAB node supports IAB through the time-frequency position where the random access opportunity is located. If the IAB node selects the random access opportunity from the overlapping part of the random access resource 2 and the random access resource 1, it also needs to display or implicitly indicate that the connected device is an IAB node through the above several other methods .

It can be seen that through the above method, when the parent node or the parent base station accessed by the parent node receives the first information, the parent node or the parent base station accessed by the parent node can be notified to obtain the type of the access device (ordinary terminal device or IAB node), which can give priority to the random access process for the IAB node, and accelerate the random access process of the IAB node.

It should be noted that the embodiments shown in FIGS. 9 and 10 can be combined with any of the embodiments shown in FIGS. 4 to 8.

FIG. 11 is a schematic structural diagram of an IAB node provided by an embodiment of this application. As shown in Figure 11, the IAB node provided in this embodiment may include:

The determining module 1101 is used to determine to initiate cell redirection or RRC re-establishment;

The processing module 1102 is configured to select a cell from at least one cell supporting IAB to initiate cell redirection or RRC re-establishment.

Optionally, the determining module 1101 is specifically configured to:

Receive an RRC release message sent by a first IAB host and determine to initiate cell redirection; the RRC release message includes the at least one IAB-supporting cell, and the first IAB host is an IAB host connected to the IAB node.

Optionally, the determining module 1101 is specifically configured to:

Receiving an RRC reconfiguration message sent by a first IAB host, where the RRC reconfiguration message includes the at least one cell that supports IAB, and the first IAB host is an IAB host connected to the IAB node;

Receiving the RRC release message sent by the first IAB host and determining to initiate cell redirection.

Optionally, the determining module 1101 is specifically configured to:

Receive an RRC rejection message sent by a first IAB host and determine to initiate cell redirection; the RRC rejection message includes the at least one IAB-supporting cell, and the first IAB host is an IAB host connected to the IAB node.

Optionally, the determining module 1101 is specifically configured to:

Acquiring the at least one IAB-supporting cell from a first IAB host or OAM, where the first IAB host is an IAB host connected to the IAB node;

Detecting a radio link failure and determining to initiate RRC re-establishment; or, receiving a radio link failure notification and determining to initiate RRC re-establishment.

Optionally, the processing module 1102 is specifically configured to:

Acquiring a first timer, where the first timer is used to instruct the IAB node to select a cell according to the at least one IAB-supporting cell to initiate RRC re-establishment valid time range;

Within the valid time range indicated by the first timer, select a cell from the at least one IAB-supporting cell to initiate RRC re-establishment.

Optionally, if the RRC re-establishment of the IAB node fails, the processing module 1102 is further configured to:

Selecting a cell from at least one cell under the first IAB host;

Initiate RRC re-establishment to a cell selected from at least one cell under the first IAB host.

Optionally, the processing module 1102 is specifically configured to:

Acquiring a second timer, where the second timer is used to instruct the IAB node to select a cell to initiate an effective time range of RRC re-establishment according to at least one cell under the first IAB host;

Within the effective time range indicated by the second timer, initiate RRC re-establishment to a cell selected from at least one cell under the first IAB donor.

Choose any cell that can be accessed;

Initiate RRC re-establishment to any accessible cell.

Optionally, it also includes a sending module, and the sending module is used to:

In the process of the cell redirection or RRC re-establishment initiated by the IAB node, first information is sent to the selected cell or the second IAB host connected to the selected cell, and the first information is used to notify the The second IAB hosts the IAB node to support IAB.

The IAB node provided in this embodiment can perform the operations performed by the IAB node in the embodiments shown in Figure 4 to Figure 10 above. The technical principles and technical effects are similar, so I won’t repeat them here.

It should be understood that the division of modules in the above devices is only a division of logical functions, and may be fully or partially integrated into one physical entity in actual implementation, or may be physically separated. In addition, the modules in the device can be all implemented in the form of software called by processing elements; they can also be all implemented in the form of hardware; part of the modules can also be implemented in the form of software called by the processing elements, and some of the modules can be implemented in the form of hardware. For example, each module can be a separately set up processing element, or it can be integrated in a certain chip of the device for implementation. In addition, it can also be stored in the memory in the form of a program, which is called and executed by a certain processing element of the device. Features. In addition, all or part of these modules can be integrated together or implemented independently. The processing element described here can also become a processor, which can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each of the above modules may be implemented by an integrated logic circuit of hardware in a processor element or implemented in a form of being called by software through a processing element.

FIG. 12 is a schematic diagram of another structure of an IAB node provided by an embodiment of the application. As shown in FIG. 12, the IAB node provided in this embodiment may include: a processor 1201, a memory 1202, and a transceiver 1203. The transceiver 1203 is used to receive data or send data, and the memory 1202 is used to store instructions. The processor 1201 is configured to execute instructions stored in the memory 1202, and is configured to execute operations performed by the IAB node in the embodiments shown in FIGS. 4 to 10 above. The technical principles and technical effects are similar, so I won’t repeat them here.

The embodiment of the present application also provides an access method for IAB nodes, which may include:

The IAB host sends a message to the IAB node; the IAB node determines to initiate cell redirection or RRC re-establishment according to the message; the IAB node selects a cell from at least one cell that supports IAB to initiate cell redirection or RRC re-establishment.

Optionally, the message sent by the IAB host to the IAB node includes:

The IAB host sends an RRC release message to the IAB node, where the RRC release message includes the at least one IAB-supporting cell.

Optionally, the message sent by the IAB host to the IAB node includes:

Sending, by the IAB host, an RRC reconfiguration message to the IAB node, where the RRC reconfiguration message includes the at least one cell that supports IAB;

The IAB host sends an RRC release message to the IAB node.

Optionally, the message sent by the IAB host to the IAB node includes:

The IAB host sends an RRC rejection message to the IAB node, where the RRC rejection message includes the at least one cell that supports IAB.

Optionally, the message sent by the IAB host to the IAB node includes:

The IAB host notifies the IAB node of the at least one cell that supports IAB;

The IAB host sends a radio link failure notification to the IAB node.

The embodiment of the present application also provides a communication system, including: an IAB node and an IAB host.

The IAB host is used to send a message to the IAB node;

The IAB node is configured to determine to initiate cell redirection or RRC re-establishment according to the message;

The IAB node is also used to select a cell from at least one cell that supports IAB to initiate cell redirection or RRC re-establishment.

The IAB node is used to perform the operations performed by the IAB node in the embodiments shown in FIGS. 4-10, and the IAB host is used to perform the operations performed by the first IAB host in the embodiments shown in FIGS. 4-10. The technical principles and technical effects are similar, so I won’t repeat them here.

An embodiment of the present application also provides a chip. The chip may include a processor, a memory, and a transceiver. The transceiver is used to receive data or send data, the memory is used to store instructions, and the processor is used to execute all instructions. The instructions stored in the memory are used to execute the operations performed by the IAB node in the embodiments shown in Figs. 4-10. The technical principles and technical effects are similar, so I won’t repeat them here.

Among them, the structure of the chip can refer to the schematic structural diagram of the IAB node shown in FIG. 12.

Optionally, the chip may implement the functions of the IAB node shown in FIG. 12 (for example, the DU part and the MT part).

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using a software program, it may be implemented in the form of a computer program product in whole or in part. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on the computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer can be a general-purpose computer, a dedicated computer, a computer network, or other programmable devices. Computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, computer instructions may be transmitted from a website, computer, server, or data center through a cable (such as Coaxial cable, optical fiber, digital subscriber line (digital subscriber line, referred to as DSL)) or wireless (such as infrared, wireless, microwave, etc.) transmission to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that can be accessed by a computer or may include one or more data storage devices such as a server or a data center that can be integrated with the medium. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, and a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk (SSD)).

The above embodiments are only used to illustrate the technical solutions of the application, not to limit it; although the application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that it can still implement the foregoing The technical solutions recorded in the examples are modified, or some or all of the technical features are equivalently replaced; these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

An IAB node access method, characterized in that it includes:

The access backhaul integrated IAB node determines to initiate cell redirection or radio resource control RRC re-establishment;

The IAB node selects a cell from at least one cell that supports IAB to initiate cell redirection or RRC re-establishment.
The method according to claim 1, wherein the determining by the IAB node to initiate cell redirection comprises:

The IAB node receives the RRC release message sent by the first IAB host and determines to initiate cell redirection; the RRC release message includes the at least one cell that supports IAB, and the first IAB host is the IAB to which the IAB node is connected Host.
The method according to claim 1, wherein the determining by the IAB node to initiate cell redirection comprises:

Receiving, by the IAB node, an RRC reconfiguration message sent by a first IAB host, where the RRC reconfiguration message includes the at least one cell that supports IAB, and the first IAB host is an IAB host to which the IAB node is connected;

The IAB node receives the RRC release message sent by the first IAB host and determines to initiate cell redirection.
The method according to claim 1, wherein the determining by the IAB node to initiate cell redirection comprises:

The IAB node receives the RRC rejection message sent by the first IAB host and determines to initiate cell redirection; the RRC rejection message includes the at least one IAB-supporting cell, and the first IAB host is the IAB to which the IAB node is connected Host.
The method according to claim 1, wherein the determining by the IAB node to initiate RRC re-establishment comprises:

The IAB node obtains the at least one IAB-supporting cell from a first IAB host or an operation and maintenance management system OAM, and the first IAB host is an IAB host to which the IAB node is connected;

The IAB node detects the radio link failure and determines to initiate RRC re-establishment; or, the IAB node receives the radio link failure notification and determines to initiate RRC re-establishment.
The method according to claim 5, wherein the IAB node selects a cell from at least one cell supporting IAB to initiate RRC re-establishment, comprising:

Acquiring, by the IAB node, a first timer, where the first timer is used to instruct the IAB node to select a cell according to the at least one IAB-supporting cell to initiate an effective time range for RRC re-establishment;

The IAB node selects a cell from the at least one IAB-supporting cell to initiate RRC re-establishment within the valid time range indicated by the first timer.
The method according to claim 6, wherein if the RRC re-establishment of the IAB node fails, the method further comprises:

The IAB node selects a cell from at least one cell under the first IAB host;

The IAB node initiates an RRC re-establishment to a cell selected from at least one cell under the first IAB donor.
The method according to claim 7, wherein the IAB node initiating RRC re-establishment to a cell selected from at least one cell under the first IAB host comprises:

Acquiring, by the IAB node, a second timer, where the second timer is used to instruct the IAB node to select a cell to initiate an RRC re-establishment effective time range according to at least one cell under the first IAB host;

The IAB node initiates an RRC re-establishment to a cell selected from at least one cell under the home of the first IAB within the valid time range indicated by the second timer.
The method according to any one of claims 5 to 8, wherein if the RRC re-establishment of the IAB node fails, the method further comprises:

The IAB node selects any cell that can be accessed;

The IAB node initiates RRC re-establishment to any accessible cell.
The method according to claim 1, further comprising:

In the process in which the IAB node initiates cell redirection or RRC re-establishment, the IAB node sends first information to the selected cell or the second IAB host connected to the selected cell, and the first information is used for Informing the second IAB host that the IAB node supports IAB.
An integrated IAB node for access and backhaul, which is characterized in that it includes:

The determining module is used to determine the initiation of cell redirection or radio resource control RRC re-establishment;

The processing module is used to select a cell from at least one cell supporting IAB to initiate cell redirection or RRC re-establishment.
The IAB node according to claim 11, wherein the determining module is specifically configured to:

Receive an RRC release message sent by a first IAB host and determine to initiate cell redirection; the RRC release message includes the at least one IAB-supporting cell, and the first IAB host is an IAB host connected to the IAB node.
The IAB node according to claim 11, wherein the determining module is specifically configured to:

Receiving an RRC reconfiguration message sent by a first IAB host, where the RRC reconfiguration message includes the at least one cell that supports IAB, and the first IAB host is an IAB host connected to the IAB node;

Receiving the RRC release message sent by the first IAB host and determining to initiate cell redirection.
The IAB node according to claim 11, wherein the determining module is specifically configured to:

Receive an RRC rejection message sent by a first IAB host and determine to initiate cell redirection; the RRC rejection message includes the at least one IAB-supporting cell, and the first IAB host is an IAB host connected to the IAB node.
The IAB node according to claim 11, wherein the determining module is specifically configured to:

Acquiring the at least one cell that supports IAB from a first IAB host or an operation and maintenance management system OAM, where the first IAB host is an IAB host connected to the IAB node;

Detecting a radio link failure and determining to initiate RRC re-establishment; or, receiving a radio link failure notification and determining to initiate RRC re-establishment.
The IAB node according to claim 15, wherein the processing module is specifically configured to:

Acquiring a first timer, where the first timer is used to instruct the IAB node to select a cell according to the at least one IAB-supporting cell to initiate RRC re-establishment valid time range;

Within the valid time range indicated by the first timer, select a cell from the at least one IAB-supporting cell to initiate RRC re-establishment.
The IAB node according to claim 16, wherein if the IAB node fails to perform RRC re-establishment, the processing module is further configured to:

Selecting a cell from at least one cell under the first IAB host;

Initiate RRC re-establishment to a cell selected from at least one cell under the first IAB host.
The IAB node according to claim 17, wherein the processing module is specifically configured to:

Acquiring a second timer, where the second timer is used to instruct the IAB node to select a cell to initiate an effective time range of RRC re-establishment according to at least one cell under the first IAB host;

Within the effective time range indicated by the second timer, initiate RRC re-establishment to a cell selected from at least one cell under the first IAB donor.
The IAB node according to any one of claims 15 to 18, wherein if the IAB node fails to perform RRC re-establishment, the processing module is further configured to:

Choose any cell that can be accessed;

Initiate RRC re-establishment to any accessible cell.
The IAB node according to claim 11, further comprising a sending module, and the sending module is configured to:

In the process of the cell redirection or RRC re-establishment initiated by the IAB node, first information is sent to the selected cell or the second IAB host connected to the selected cell, and the first information is used to notify the The second IAB hosts the IAB node to support IAB.
An integrated IAB node for access and backhaul, which is characterized by comprising a processor and a transceiver; the transceiver is used to communicate with other devices, and the processor is used to execute instructions so that the IAB node executes as claimed The method of any one of 1 to 10.
An IAB node access method, characterized in that it includes:

The access backhaul integrated IAB host sends a message to the IAB node;

The IAB node determines to initiate cell redirection or radio resource control RRC re-establishment according to the message;

The IAB node selects a cell from at least one cell that supports IAB to initiate cell redirection or RRC re-establishment.
The method according to claim 22, wherein the sending of a message by the IAB host to an IAB node comprises:

The IAB host sends an RRC release message to the IAB node, where the RRC release message includes the at least one cell that supports IAB.
The method according to claim 22, wherein the sending of a message by the IAB host to an IAB node comprises:

Sending, by the IAB host, an RRC reconfiguration message to the IAB node, where the RRC reconfiguration message includes the at least one cell that supports IAB;

The IAB host sends an RRC release message to the IAB node.
The method according to claim 22, wherein the sending of a message by the IAB host to an IAB node comprises:

The IAB host sends an RRC rejection message to the IAB node, where the RRC rejection message includes the at least one cell that supports IAB.
The method according to claim 22, wherein the sending of a message by the IAB host to an IAB node comprises:

The IAB host notifies the IAB node of the at least one cell that supports IAB;

The IAB host sends a radio link failure notification to the IAB node.
A communication system, characterized in that it includes: an integrated backhaul IAB node and an IAB host;

The IAB host is used to send a message to the IAB node;

The IAB node is configured to determine to initiate cell redirection or radio resource control RRC re-establishment according to the message;

The IAB node is also used to select a cell from at least one cell that supports IAB to initiate cell redirection or RRC re-establishment.
A storage medium, characterized in that it stores computer-executable instructions, and when the computer-executable instructions are executed by a processor, the method according to any one of claims 1 to 10, or the The method of any one of 26.