EP-4149161-B1 - ELECTRONIC APPARATUS, RADIO COMMUNICATION METHOD, AND COMPUTER-READABLE STORAGE MEDIUM

EP4149161B1EP 4149161 B1EP4149161 B1EP 4149161B1EP-4149161-B1

Inventors

ZHANG, Shumeng
YUAN, Yingting
LIU, RUI
CHEN, Guanyu
HUANG, Zhihan
LIU, Jinghang
CUI, Tao
XU, XIAODONG

Dates

Publication Date: 20260506
Application Date: 20210430

Claims (11)

An electronic device (400) for a core network node, comprising processing circuitry (410, 420, 430, 440) configured to: determine a topological position of an integrated access and backhaul, IAB, node in an IAB network at a next time instant, the topological position comprising a target parent node and a target donor node of the IAB node; send a switching request to the target donor node of the IAB node at the next time instant, to request that the IAB node is switched at the next time instant to the target parent node and the target donor node at the next time instant; and send a switching notification to a source donor node of the IAB node at a current time instant, the switching notification comprising the topological position of the IAB node at the next time instant, so that the IAB node is connected to both the source donor node at the current time instant and the target donor node at the next time instant on a control plane; wherein the circuitry is configured to determine the topological position of the IAB node at the next time instant according to a historical geographical position and a historical topological position of the IAB node, received at the core network node from an IAB donor node.
The electronic device according to claim 1, wherein the processing circuitry is further configured to: determine a geographical position of the IAB node at the next time instant based on the historical geographical position of the IAB node; and determine the topological position of the IAB node at the next time instant according to the geographical position of the IAB node at the next time instant and the historical topological position of the IAB node.
The electronic device according to claim 1, wherein the processing circuitry is further configured to: receive the historical topological position of the IAB node from the source donor node at the current time instant.
The electronic device according to claim 1, wherein the processing circuitry is further configured to: receive a switching response from the target donor node at the next time instant, to determine that the IAB node is allowed, at the next time instant, to be switched to the target parent node and the target donor node at the next time instant.
An electronic device (600) for an IAB donor node, comprising processing circuitry (610, 620, 630) configured to: receive a switching notification from a core network node that comprises a topological position of an integrated access and backhaul, IAB, node in an IAB network at a next time instant, the topological position comprising a target parent node and a target donor node of the IAB node; and send the switching notification to the IAB node, so that the IAB node is connected to both the electronic device and the donor node at the next time instant on a control plane; wherein the processing circuitry is further configured to: send a historical topological position of the IAB node to the core network node, for the core network node to determine the topological position of the IAB node at the next time instant.
The electronic device according to claim 5, wherein the processing circuitry is further configured to: send the switching notification through an RRC reconfiguration message.
The electronic device according to claim 5, wherein the processing circuitry is further configured to: in response to a switching success message from the donor node at the next time instant, switch the IAB node from the electronic device to the target donor node at the next time instant on a user plane.
The electronic device according to claim 5, wherein the processing circuitry is further configured to: in response to a release message from the target donor node at the next time instant, release connection with the IAB node on the control plane.
An electronic device (810, 820, 830) for an IAB node, comprising processing circuitry configured to: receive a switching notification from a source donor node of the electronic device at a current time instant, wherein the switching notification comprises a topological position of the electronic device in an integrated access and backhaul, IAB, network at a next time instant, and the topological position comprises a target parent node and a target donor node of the electronic device, wherein the topological position of the IAB node at the next time instant is determined by a core network node according to a historical geographical position and a historical topological position of the IAB node; and connect to the target donor node at the next time instant on a control plane, while connecting to the source donor node at the current time instant on the control plane.
The electronic device according to claim 9, wherein the processing circuitry is further configured to: perform a random access process to connect a mobile terminal (MT) unit in the electronic device to the parent node at the next time instant.
The electronic device according to claim 9, wherein the processing circuitry is further configured to: connect a distributed unit, DU, in the electronic device to the donor node at the next time instant on the control plane.

Description

FIELD Embodiments of the present disclosure generally relate to the field of wireless communications, and in particular to an electronic device, a wireless communication method, and a computer-readable storage medium. Specially, the present disclosure relates to an electronic device for a core network in a wireless communication system, an electronic device for a donor node in a wireless communication system, an electronic device for an integrated access and backhaul (IAB) node in a wireless communication system, an electronic device as a user equipment in a wireless communication system, a wireless communication method performed by an electronic device in a core network, a wireless communication method performed by a donor node, a wireless communication method performed by an IAB node, a wireless communication method performed by a user equipment, and a computer-readable storage medium. BACKGROUND Compared with a LTE communication system, a 5G new radio (NR) communication system may use a wider bandwidth, such as millimeter wave band, and may use large-scale antenna and a multi-beam system. Therefore, 5G may provide a higher system rate and provide a condition for IAB technology. In an IAB network, a donor node (such as an IAB donor) may be connected to a core network through a cable, and an IAB node as a relay is directly or indirectly connected to the donor node, so as to connect to the core network. The donor node further serves as a donor base station. The IAB node integrates a wireless access link and a wireless backhaul (BH) link. The access link is a communication link between UE and the IAB node, and the backhaul link is a communication link between IAB nodes or between the IAB node and the donor base station. A user equipment (UE) may be connected to the IAB node or the donor node. That is, the UE may be connected to the donor node through one or more IAB nodes or directly to the donor node. IAB technology is more suitable for a dense scenario, which can reduce a burden of deploying a wired transmission network and expand coverage of a cell. Figure 1 is a schematic structural diagram showing an IAB network. As shown in Figure 1, an IAB donor node A is connected to the core network, an IAB node B and an IAB node C are connected to the IAB donor node A through the backhaul link, and the user equipment in the network may be connected to the IAB node, or connected to the IAB donor node. An important application scenario of the IAB technology is high-speed train. Figure 2 is a schematic diagram showing a scenario in which IAB technology is applied to a train. In Figure 2, a train with a length L travels along a rail, one or more access devices are arranged on the train, and the access devices may serve as IAB nodes in the IAB network. Users on the train, such as UE1 and UE2, are connected to the access devices through the access link. The access devices are connected to an eNB close to the rail through the backhaul link. The eNB close to the rail may serve as an IAB node in the IAB network, and is directly connected to the IAB donor node or connected to the IAB donor node through another IAB node. Due to rapid movement of the train, the access devices may be switched from an IAB donor node to another IAB donor node. There is a delay from a time instant when the access devices are disconnected from a source IAB donor node to a time instant when the access devices are connected to a new IAB donor node. A time period is required for performing radio link failure (RLF) detection after the access devices are connected to the new IAB donor node, resulting in a loss of service for a UE connected to the access devices and service interruption. During a time period from the time instant when the access devices are disconnected from a source IAB donor node to a time instant when the UE re-accesses the network after RLF discovery, the UE is in a state of service interruption. It can be seen that the UE loses service for a long time. Therefore, it is required to propose a technical solution to optimize a switching process in an IAB network, so as to avoid interruption of service for the UE or reduce a time period for which service for the UE is interrupted. Prior art includes: WO 2019/246446 A1 disclosing an inter donor handover of IAB nodes to achieve lower latency, better backhaul signal or load balancing, whereby the target donor node can be determined based on IAB node moving speed or moving direction. and WO 2020/066605 A1 disclosing inter donor handover by IAB nodes due to radio link failure. SUMMARY The invention is defined by the appended claims. With the electronic device, the wireless communication method and the computer-readable storage medium according to the present disclosure, the electronic device in the core network may predict the parent node and the donor node of the IAB node, so that the IAB node may be connected to both the source donor node and the target donor node on the control plane. In t