Switching method and apparatus, and storage medium

Abstract

Provided in the present disclosure are a switching method and apparatus, and a storage medium. The method comprises: acquiring related information of a target logical DU cell of a mobile IAB node; on the basis of the related information, switching a user equipment (UE), which is served by the mobile IAB node, to the target logical DU cell of the mobile IAB node from a source logical DU cell of the mobile IAB node.

Description

Switching method, device and storage medium

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application number 202311014905.X, filed on August 11, 2023, entitled “Switching method, device and storage medium,” which is incorporated herein by reference in its entirety. Technical Field

[0003] The present disclosure relates to the field of communication technologies, and in particular to a switching method, device, and storage medium. Background Art

[0004] Related technologies are beginning to explore the integration of mobile access and backhaul (IAB) nodes, increasing support for mobility scenarios. For example, IAB nodes can be installed in high- or low-speed vehicles to serve users on board. Therefore, it was determined that support for changing the anchor centralized unit (donor-CU) of the integrated access and backhaul distributed unit (IAB-DU) was needed, known as IAB-DU migration.

[0005] Since the source logical distribution unit DU needs to release the F1 connection with the source donor-CU after the IAB-DU migration, the terminal / user equipment (User Equipment, UE) served by the source logical DU needs to be switched to another cell. According to relevant technologies, the source donor-CU can determine the target cell to switch the UE based on the UE's measurement report results of the neighboring cells. When the cell of the source logical DU and the cell of the target logical DU use the same downlink frequency, the cell of the source logical DU and the cell of the target logical DU cannot be activated at the same time. Therefore, the UE served by the source logical DU cannot measure the signal quality of the target logical DU cell, resulting in the source donor-CU being unable to determine the target cell to which the UE is switched.

[0006] Summary of the Invention

[0007] The embodiments of the present disclosure provide a handover method, apparatus, and storage medium to solve the technical problem in related technologies that a source donor-CU cannot determine a target cell for UE handover.

[0008] In a first aspect, an embodiment of the present disclosure provides a handover method, which is applied to a source anchor centralized unit (donor-CU) of a source logical distribution unit (DU) of a mobile access and backhaul integrated IAB node, comprising:

[0009] Obtaining relevant information of a target logical DU cell of the mobile IAB node;

[0010] Hand over the user equipment UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node based on the relevant information.

[0011] In some embodiments, the switching, based on the relevant information, of the UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node includes:

[0012] Configuring the UE to measure the target logical DU cell;

[0013] Determine a target logical DU cell for handing over the UE to the mobile IAB node based on the measurement result.

[0014] In some embodiments, the switching, based on the relevant information, of the UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node includes:

[0015] Determine to hand over the UE to the target logical DU cell based on the correspondence or co-location relationship between the target logical DU cell and the source logical DU cell.

[0016] In some embodiments, the downlink frequency of the target logical DU cell is the same as that of the source logical DU cell, or the downlink frequency of the target logical DU cell is different from that of the source logical DU cell.

[0017] In some embodiments, obtaining relevant information of a target logical DU cell of the mobile IAB node includes:

[0018] The relevant information sent by the source logical DU of the mobile IAB node is obtained through an F1 interface application protocol F1AP message.

[0019] In some embodiments, the relevant information includes one or more of the following information:

[0020] Identification information of the target logical DU cell;

[0021] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0022] Downlink frequency information of the target logical DU cell;

[0023] Measurement reference signal configuration information of the target logical DU cell.

[0024] In some embodiments, the method further comprises:

[0025] receiving a handover command for the UE from a target donor-CU of a target logical DU of the mobile IAB node;

[0026] The handover command is sent to the UE.

[0027] In a second aspect, an embodiment of the present disclosure provides a handover method, applied to a mobile IAB node, comprising:

[0028] Send relevant information of the target logical DU cell of the mobile IAB node; the relevant information is used to switch the UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node.

[0029] In some embodiments, the method further comprises:

[0030] Determine a beam for the UE to perform RACH-less handover in the target logical DU cell;

[0031] Configuring a synchronization signal block SSB corresponding to the beam and a configuration authorization CG physical uplink shared channel PUSCH resource for the SSB; the PUSCH resource is used by the UE to send an initial uplink message of RACH-less switching to the target logical DU cell;

[0032] The first configuration information is sent to the target donor-CU of the target logical DU of the mobile IAB node through an F1AP message, wherein the first configuration information is used to indicate the SSB corresponding to the beam and the CG PUSCH resources for the SSB.

[0033] In some embodiments, the method further comprises:

[0034] Determining a beam for the UE to perform RACH-less handover in the target logical DU cell;

[0035] The physical downlink control channel PDCCH associated with the SSB corresponding to the beam is used to dynamically schedule the UE to use the authorized PUSCH resources; the PUSCH resources are used by the UE to send an initial uplink message to the target logical DU cell.

[0036] In some embodiments, determining a beam for the UE to perform RACH-less handover in the target logical DU cell includes:

[0037] The beam for the UE to perform RACH-less switching in the target logical DU is determined based on the measurement result of the UE on the target logical DU cell included in the switching preparation information.

[0038] In some embodiments, determining a beam for the UE to perform RACH-less handover in the target logical DU cell includes:

[0039] Determine a beam used by the UE in the source logical DU cell;

[0040] The beam used by the UE for RACH-less handover in the target logical DU cell is determined based on the beam used by the UE in the source logical DU cell.

[0041] In some embodiments, sending relevant information about the target logical DU cell of the mobile IAB node includes:

[0042] The relevant information of the target logical DU cell of the mobile IAB node is sent to the source donor-CU of the source logical DU of the mobile IAB node through an F1AP message.

[0043] In some embodiments, the relevant information includes one or more of the following information:

[0044] Identification information of the target logical DU cell;

[0045] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0046] Downlink frequency information of the target logical DU cell;

[0047] Measurement reference signal configuration information of the target logical DU cell.

[0048] In a third aspect, an embodiment of the present disclosure provides a handover method, applied to a UE, including:

[0049] Determine the PUSCH resources of the SSB corresponding to the beam for RACH-less handover in the target cell;

[0050] An initial uplink message is sent to the target cell using the PUSCH resource.

[0051] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less handover in the target cell includes:

[0052] Receiving a handover command sent by a network device; the handover command includes first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB;

[0053] Based on the first configuration information, the SSB corresponding to the beam for RACH-less switching in the target cell is selected and the PUSCH resources for the SSB are determined.

[0054] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less handover in the target cell includes:

[0055] receiving a handover command sent by a network device; the handover command does not include first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB;

[0056] Determine that the SSB corresponding to the PDCCH used by the target cell to schedule the UE is the SSB corresponding to the beam for performing RACH-less switching in the target cell, detect the PDCCH used by the target cell to schedule the UE; and determine the PUSCH resources scheduled by the PDCCH.

[0057] In some embodiments, the handover command further includes second configuration information, where the second configuration information is used to indicate to the UE an SSB receiving power threshold for selecting SSB;

[0058] The selecting the SSB corresponding to the beam for performing RACH-less switching in the target cell includes:

[0059] Selecting an SSB with a reception power higher than the SSB reception power threshold from among the SSBs indicated in the first configuration information as the SSB corresponding to the beam for RACH-less switching in the target cell; or,

[0060] The SSB whose receiving power corresponding to the PDCCH is higher than the SSB receiving power threshold is selected as the SSB corresponding to the beam for RACH-less switching in the target cell.

[0061] In some embodiments, the method further comprises:

[0062] If the receiving power of the SSB indicated in the first configuration information is lower than the SSB receiving power threshold, or the receiving power threshold of the SSB corresponding to the PDCCH is lower than the SSB receiving power threshold, a random access process is initiated to access the target cell.

[0063] In a fourth aspect, an embodiment of the present disclosure provides a source donor-CU of a source logical DU of a mobile IAB node, comprising a memory, a transceiver, and a processor;

[0064] A memory for storing a computer program; a transceiver for transmitting and receiving data under the control of the processor; and a processor for reading the computer program in the memory and performing the following operations:

[0065] Obtaining relevant information of a target logical DU cell of the mobile IAB node;

[0066] Hand over the UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node based on the relevant information.

[0067] In some embodiments, the switching, based on the relevant information, of the UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node includes:

[0068] Configuring the UE to measure the target logical DU cell;

[0069] Determine a target logical DU cell for handing over the UE to the mobile IAB node based on the measurement result.

[0070] In some embodiments, the switching, based on the relevant information, of the UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node includes:

[0071] Determine to hand over the UE to the target logical DU cell based on the correspondence or co-location relationship between the target logical DU cell and the source logical DU cell.

[0072] In some embodiments, the downlink frequency of the target logical DU cell is the same as that of the source logical DU cell, or the downlink frequency of the target logical DU cell is different from that of the source logical DU cell.

[0073] In some embodiments, obtaining relevant information of a target logical DU cell of the mobile IAB node includes:

[0074] The relevant information sent by the source logical DU of the mobile IAB node is obtained through an F1AP message.

[0075] In some embodiments, the relevant information includes one or more of the following information:

[0076] Identification information of the target logical DU cell;

[0077] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0078] Downlink frequency information of the target logical DU cell;

[0079] Measurement reference signal configuration information of the target logical DU cell.

[0080] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0081] receiving a handover command for the UE from a target donor-CU of a target logical DU of the mobile IAB node;

[0082] The handover command is sent to the UE.

[0083] In a fifth aspect, an embodiment of the present disclosure provides a mobile IAB node, including a memory, a transceiver, and a processor;

[0084] A memory for storing a computer program; a transceiver for transmitting and receiving data under the control of the processor; and a processor for reading the computer program in the memory and performing the following operations:

[0085] Send relevant information of the target logical DU cell of the mobile IAB node; the relevant information is used to switch the UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node.

[0086] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0087] Determining a beam for the UE to perform RACH-less handover in the target logical DU cell;

[0088] Configure the SSB corresponding to the beam and the CG PUSCH resource for the SSB; the PUSCH resource is used by the UE to send an initial uplink message of RACH-less switching to the target logical DU cell;

[0089] The first configuration information is sent to the target donor-CU of the target logical DU of the mobile IAB node through an F1AP message, wherein the first configuration information is used to indicate the SSB corresponding to the beam and the CG PUSCH resources for the SSB.

[0090] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0091] Determining a beam for the UE to perform RACH-less handover in the target logical DU cell;

[0092] The SSB-related PDCCH corresponding to the beam is used to dynamically schedule the UE to use the authorized PUSCH resources; the PUSCH resources are used by the UE to send an initial uplink message to the target logical DU cell.

[0093] In some embodiments, determining a beam for the UE to perform RACH-less handover in the target logical DU cell includes:

[0094] The beam for the UE to perform RACH-less switching in the target logical DU is determined based on the measurement result of the UE on the target logical DU cell included in the switching preparation information.

[0095] In some embodiments, determining a beam for the UE to perform RACH-less handover in the target logical DU cell includes:

[0096] Determine a beam used by the UE in the source logical DU cell;

[0097] The beam used by the UE for RACH-less handover in the target logical DU cell is determined based on the beam used by the UE in the source logical DU cell.

[0098] In some embodiments, sending relevant information about the target logical DU cell of the mobile IAB node includes:

[0099] The relevant information of the target logical DU cell of the mobile IAB node is sent to the source donor-CU of the source logical DU of the mobile IAB node through an F1AP message.

[0100] In some embodiments, the relevant information includes one or more of the following information:

[0101] Identification information of the target logical DU cell;

[0102] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0103] Downlink frequency information of the target logical DU cell;

[0104] Measurement reference signal configuration information of the target logical DU cell.

[0105] In a sixth aspect, an embodiment of the present disclosure provides a UE, including a memory, a transceiver, and a processor;

[0106] A memory for storing a computer program; a transceiver for transmitting and receiving data under the control of the processor; and a processor for reading the computer program in the memory and performing the following operations:

[0107] Determine the PUSCH resources of the SSB corresponding to the beam for RACH-less handover in the target cell;

[0108] An initial uplink message is sent to the target cell using the PUSCH resource.

[0109] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less handover in the target cell includes:

[0110] Receiving a handover command sent by a network device; the handover command includes first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB;

[0111] Based on the first configuration information, the SSB corresponding to the beam for RACH-less switching in the target cell is selected and the PUSCH resources for the SSB are determined.

[0112] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less handover in the target cell includes:

[0113] receiving a handover command sent by a network device; the handover command does not include first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB;

[0114] Determine that the SSB corresponding to the PDCCH used by the target cell to schedule the UE is the SSB corresponding to the beam for performing RACH-less switching in the target cell, detect the PDCCH used by the target cell to schedule the UE; and determine the PUSCH resources scheduled by the PDCCH.

[0115] In some embodiments, the handover command further includes second configuration information, where the second configuration information is used to indicate to the UE an SSB receiving power threshold for selecting SSB;

[0116] The selecting the SSB corresponding to the beam for performing RACH-less switching in the target cell includes:

[0117] Selecting an SSB with a reception power higher than the SSB reception power threshold from among the SSBs indicated in the first configuration information as the SSB corresponding to the beam for RACH-less switching in the target cell; or,

[0118] The SSB whose receiving power corresponding to the PDCCH is higher than the SSB receiving power threshold is selected as the SSB corresponding to the beam for RACH-less switching in the target cell.

[0119] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0120] If the receiving power of the SSB indicated in the first configuration information is lower than the SSB receiving power threshold, or the receiving power threshold of the SSB corresponding to the PDCCH is lower than the SSB receiving power threshold, a random access process is initiated to access the target cell.

[0121] In a seventh aspect, an embodiment of the present disclosure provides a switching device, including:

[0122] An acquisition module, configured to acquire relevant information of a target logical DU cell of a mobile IAB node;

[0123] A handover module is configured to handover a user equipment UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node based on the relevant information.

[0124] In some embodiments, the switching module includes a configuration unit and a first switching unit;

[0125] The configuration unit is used to configure the UE to measure the target logical DU cell;

[0126] The first switching unit is configured to determine, based on the measurement result, a target logical DU cell for switching the UE to the mobile IAB node.

[0127] In some embodiments, the switching module includes a second switching unit;

[0128] The second switching unit is configured to determine, based on a correspondence relationship or a co-location relationship between the target logical DU cell and the source logical DU cell, to switch the UE to the target logical DU cell.

[0129] In some embodiments, the downlink frequency of the target logical DU cell is the same as that of the source logical DU cell, or the downlink frequency of the target logical DU cell is different from that of the source logical DU cell.

[0130] In some embodiments, the acquisition module is specifically configured to:

[0131] The relevant information sent by the source logical DU of the mobile IAB node is obtained through an F1 interface application protocol F1AP message.

[0132] In some embodiments, the relevant information includes one or more of the following information:

[0133] Identification information of the target logical DU cell;

[0134] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0135] Downlink frequency information of the target logical DU cell;

[0136] Measurement reference signal configuration information of the target logical DU cell.

[0137] In some embodiments, the apparatus further comprises a receiving module and a third sending module;

[0138] The receiving module is configured to receive a handover command for the UE from a target donor-CU of a target logical DU of the mobile IAB node;

[0139] The third sending module is configured to send the handover command to the UE.

[0140] In an eighth aspect, an embodiment of the present disclosure provides a switching device, including:

[0141] The first sending module is configured to send relevant information of a target logical DU cell of a mobile IAB node; the relevant information is used to switch a UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node.

[0142] In some embodiments, the apparatus further comprises a second determining module, a configuring module, and a fourth sending module;

[0143] The second determining module is configured to determine a beam for the UE to perform RACH-less handover in the target logical DU cell;

[0144] The configuration module is used to configure the synchronization signal block SSB corresponding to the beam and the configuration authorization CG physical uplink shared channel PUSCH resource for the SSB; the PUSCH resource is used by the UE to send the initial uplink message of RACH-less switching to the target logical DU cell;

[0145] The fourth sending module is used to send the first configuration information to the target donor-CU of the target logical DU of the mobile IAB node through an F1AP message, wherein the first configuration information is used to indicate the SSB corresponding to the beam and the CG PUSCH resources for the SSB.

[0146] In some embodiments, the apparatus further comprises a second determination module and a scheduling module;

[0147] The second determining module is configured to determine a beam for the UE to perform RACH-less switching in the target logical DU cell;

[0148] The scheduling module is used to dynamically schedule the UE to use the authorized PUSCH resources using the physical downlink control channel PDCCH related to the SSB corresponding to the beam; the PUSCH resources are used by the UE to send an initial uplink message to the target logical DU cell.

[0149] In some embodiments, the second determining module includes a first determining unit;

[0150] The first determining unit is configured to determine a beam for the UE to perform RACH-less switching in the target logical DU based on a measurement result of the UE on the target logical DU cell included in the switching preparation information.

[0151] In some embodiments, the second determining module includes a second determining unit and a third determining unit;

[0152] The second determining unit is configured to determine a beam used by the UE in the source logical DU cell;

[0153] The third determining unit is configured to determine, based on the beam used by the UE in the source logical DU cell, a beam for the UE to perform RACH-less switching in the target logical DU cell.

[0154] In some embodiments, the first sending module is specifically configured to:

[0155] The relevant information of the target logical DU cell of the mobile IAB node is sent to the source donor-CU of the source logical DU of the mobile IAB node through an F1AP message.

[0156] In some embodiments, the relevant information includes one or more of the following information:

[0157] Identification information of the target logical DU cell;

[0158] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0159] Downlink frequency information of the target logical DU cell;

[0160] Measurement reference signal configuration information of the target logical DU cell.

[0161] In a ninth aspect, an embodiment of the present disclosure provides a switching device, including:

[0162] The first determination module is used to determine the PUSCH resource of the SSB corresponding to the beam for RACH-less handover in the target cell;

[0163] The second sending module is configured to send an initial uplink message to the target cell by using the PUSCH resources.

[0164] In some embodiments, the first determining module includes a receiving unit and a fourth determining unit;

[0165] The receiving unit is configured to receive a handover command sent by a network device; the handover command includes first configuration information; the first configuration information is configured to indicate an SSB corresponding to the beam for performing RACH-less handover in the target cell and a CG PUSCH resource for the SSB;

[0166] The fourth determination unit is used to select the SSB corresponding to the beam for RACH-less switching in the target cell based on the first configuration information and determine the PUSCH resources for the SSB.

[0167] In some embodiments, the first determining module includes a receiving unit and a fifth determining unit;

[0168] The receiving unit is configured to receive a handover command sent by a network device; the handover command does not include first configuration information; the first configuration information is configured to indicate an SSB corresponding to the beam for performing RACH-less handover in the target cell and a CG PUSCH resource for the SSB;

[0169] The fifth determination unit is used to determine that the SSB corresponding to the PDCCH used by the target cell to schedule the UE is the SSB corresponding to the beam performing RACH-less switching in the target cell, detect the PDCCH used by the target cell to schedule the UE; and determine the PUSCH resources scheduled by the PDCCH.

[0170] In some embodiments, the handover command further includes second configuration information, where the second configuration information is used to instruct the UE to select an SSB receive power threshold for SSB use;

[0171] The fourth determining unit is specifically configured to:

[0172] Selecting an SSB with a reception power higher than the SSB reception power threshold from among the SSBs indicated in the first configuration information as the SSB corresponding to the beam for RACH-less switching in the target cell; or,

[0173] The SSB whose receiving power corresponding to the PDCCH is higher than the SSB receiving power threshold is selected as the SSB corresponding to the beam for RACH-less switching in the target cell.

[0174] In some embodiments, the apparatus further comprises an initiating module;

[0175] The initiating module is used to initiate a random access process to access the target cell if the receiving power of the SSB indicated in the first configuration information is lower than the SSB receiving power threshold, or the receiving power threshold of the SSB corresponding to the PDCCH is lower than the SSB receiving power threshold.

[0176] In the tenth aspect, an embodiment of the present disclosure further provides a non-transitory readable storage medium, wherein the non-transitory readable storage medium stores a computer program, and the computer program is used to enable the processor to execute the switching method described in the first aspect, the second aspect or the third aspect as described above.

[0177] In the eleventh aspect, an embodiment of the present disclosure further provides a processor-readable storage medium, wherein the processor-readable storage medium stores a computer program, and the computer program is used to enable the processor to execute the switching method described in the first aspect, the second aspect or the third aspect above.

[0178] In the twelfth aspect, an embodiment of the present disclosure further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and the computer program is used to enable a computer to execute the switching method described in the first aspect, the second aspect or the third aspect above.

[0179] In a thirteenth aspect, an embodiment of the present disclosure further provides a communication device, in which a computer program is stored, and the computer program is used to enable the communication device to execute the switching method described in the first aspect, the second aspect or the third aspect above.

[0180] In a fourteenth aspect, an embodiment of the present disclosure further provides a chip product, wherein a computer program is stored in the chip product, and the computer program is used to enable the chip product to execute the switching method described in the first aspect, the second aspect or the third aspect above.

[0181] The switching method, device, and storage medium provided by the present disclosure enable the source logical DU of the mobile IAB node to report relevant information of the target logical DU cell of the mobile IAB node to the source donor-CU of the source logical DU of the mobile IAB node, so that the source donor-CU of the source logical DU of the mobile IAB node promptly obtains the target cell to which the UE is switched, thereby enabling the UE to switch between IAB logical DUs. BRIEF DESCRIPTION OF THE DRAWINGS

[0182] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or related technologies, the following is a brief introduction to the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0183] Figure 1 is a schematic diagram of the IAB system;

[0184] Figure 2 is a schematic diagram of the IAB network architecture;

[0185] Figure 3 is a schematic diagram of a Parent IAB-node and a Child IAB-node;

[0186] Figure 4 is a schematic diagram of the IAB system F1-U protocol stack;

[0187] Figure 5 is a schematic diagram of the IAB system F1-C protocol stack;

[0188] FIG6 is a schematic diagram of the routing function of the IAB system;

[0189] FIG7 is a schematic diagram of the IAB-DU migration process;

[0190] FIG8 is a flowchart of a switching method according to an embodiment of the present disclosure;

[0191] FIG9 is a second flow chart of a switching method according to an embodiment of the present disclosure;

[0192] FIG10 is a third flow chart of a switching method according to an embodiment of the present disclosure;

[0193] FIG11 is a schematic diagram of a switching principle according to an embodiment of the present disclosure;

[0194] FIG12 is a second schematic diagram of a switching principle provided by an embodiment of the present disclosure;

[0195] FIG13 is a schematic structural diagram of a source donor-CU of a source logical DU of a mobile IAB node provided by an embodiment of the present disclosure;

[0196] FIG14 is a schematic structural diagram of a mobile IAB node provided in an embodiment of the present disclosure;

[0197] FIG15 is a schematic structural diagram of a UE provided in an embodiment of the present disclosure;

[0198] FIG16 is a schematic diagram of a structure of a switching device according to an embodiment of the present disclosure;

[0199] FIG17 is a second structural diagram of a switching device provided in an embodiment of the present disclosure;

[0200] FIG18 is a third structural diagram of the switching device provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0201] Future seamless cellular network deployment requires highly flexible and ultra-dense New Radio (NR) cell deployment. Ultra-dense networks are one of the goals of the fifth-generation mobile communication (5G). Deploying an NR network that doesn't require wired backhaul is crucial to achieving 5G's ultra-dense network. Because 5G millimeter waves reduce cell coverage, wireless self-backhaul systems must also be multi-hop to meet deployment requirements. 5G's high bandwidth, massive Multiple Input Multiple Output (MIMO), and beamforming make it easier to develop wireless self-backhaul systems for ultra-dense NR cells for 5G than for Long Term Evolution (LTE). To develop this multi-hop system with wireless self-backhaul, 3GPP initiated research and standardization of the IAB (Integrated Access and Backhaul for NR) project in Release 16. Figure 1 is a schematic diagram of the IAB system. As shown in Figure 1, access and backhaul adopt NR's Uu air interface wireless transmission. The relay node supports both access and backhaul functions. The relay node multiplexes the access link and backhaul link in the time domain, frequency domain or spatial domain. The access and backhaul links can use the same or different frequency bands.

[0202] Figure 2 shows the IAB network architecture. Figure 2a illustrates the IAB architecture in SA mode, and Figure 2b illustrates the IAB architecture in EN-DC mode. The relay node is referred to as the IAB-node, which supports both access and backhaul functions. The last-hop access node on the network side is called the IAB-donor, which supports gNB functionality and IAB-node access. All UE data is backhauled to the IAB-donor via one or more hops via the IAB-node.

[0203] Figure 3 illustrates a parent IAB-node and child IAB-node. As shown in Figure 3, the IAB-node functions are divided into two parts: gNB-DU functions, called the IAB-DU, and UE functions, called the IAB-MT. The IAB-DU implements network-side device functions, serving one or more cells and connecting to downstream child IAB-nodes. It provides NR air interface access to the UE and downstream child IAB-nodes and establishes an F1 connection with the IAB donor-CU. The IAB-MT implements some terminal device functions and connects to the upstream parent IAB-node or IAB-donor DU. The IAB-MT includes physical layer, layer 2, RRC, and NAS layer functions, and is indirectly connected to the IAB donor-CU and the core network. The IAB-node can access the network in either SA mode or EN-DC mode.

[0204] Figure 4 is a schematic diagram of the IAB system's F1-U protocol stack, and Figure 5 is a schematic diagram of the IAB system's F1-C protocol stack. As shown in Figures 4 and 5, F1-U and F1-C are built on the transport layer (IP) between the IAB-DU and the IAB-donor-CU, which goes through two wireless backhaul hops and one wired backhaul hop. On the backhaul link, the transport layer (IP) is carried on the Backhaul Adaptation Protocol (BAP) sublayer. The BAP entity in the IAB-node implements the IAB system's routing function, and the IAB-donor CU provides the routing table. BAP protocol data units (PDUs) are transmitted on the backhaul link's Radio Link Control (RLC) channel. The IAB-donor can configure multiple RLC channels on the backhaul link to carry services with different priorities and Quality of Service (QoS). The BAP entity maps BAP PDUs to different backhaul RLC channels.

[0205] Figure 6 shows the routing functionality of the IAB system. As shown in Figure 6, the routing function of the IAB system is implemented by the BAP layer. Each IAB node stores a routing table (BH routing configuration) and an RLC channel mapping table (BH RLC Channel Mapping Configuration). The BAP entity performs routing based on the routing table, RLC channel mapping table, and the routing ID in the BAP layer packet header. The Routing ID contains the destination BAP address and the path identifier.

[0206] The routing table contains the mapping between Routing IDs and next-hop addresses. The RLC channel mapping table contains the mapping between the previous-hop address, ingress RLC channel ID, and next-hop address and egress RLC channel ID. For each data packet, the next-hop address can be found in the routing table using the Routing ID in the packet header. Both the previous-hop address and the ingress RLC channel ID are known. Once the next-hop address is determined, the egress RLC channel ID can be found using the RLC channel mapping table based on the previous-hop address, ingress RLC channel ID, and next-hop address.

[0207] NR R18 started the discussion on mobile IAB nodes and increased support for mobility scenarios, for example, installing IAB nodes on high-speed or low-speed moving vehicles to serve users on the vehicle. First, R18 determined the need to support continuous IAB-MT switching scenarios, supporting the switching of IAB-MT between two non-F1 terminated donor-CUs without changing the donor-CU of the IAB-DU, also known as the IAB-MT migration process. However, when the donor-CU of the IAB-DU is not changed (that is, the F1 terminated donor-CU is not changed), the F1 service always needs to be transferred from the topological domain of the IAB-MT to the donor-CU of the IAB-DU. If the activity range of the mobile IAB node is large, the donor-CU of the IAB-MT is far away from the donor-CU of the IAB-DU, which will cause service transmission delays. Therefore, R18 determined the need to support changing the F1 terminated donor-CU, also known as IAB-DU migration.

[0208] Figure 7 is a schematic diagram of the IAB-DU migration process. As shown in Figure 7, during IAB-DU migration, the donor-CU of the IAB-DU changes from the source donor-CU to the target donor-CU. When executing this process, the IAB node needs to implement two logical DU functions. The target logical DU of the IAB node establishes an F1 connection with the target donor-CU. At this time, the original F1 connection is retained between the source logical DU of the IAB node and the source donor-CU. Through the two logical DUs and the corresponding F1 connections, the UE served by the IAB node can be switched from the source donor-CU and source logical DU to the target donor-CU and target logical DU. The source logical DU of the IAB node then releases the F1 connection with the source donor-CU. Since the original logical DU cell and the target logical DU cell are co-located, in principle, the UE's timing advance (TA) for the two cells is the same, and random access channel-less (RACH-less) switching can be supported.

[0209] Problem 1: Since the source logical DU needs to release the F1 connection with the source donor-CU after IAB-DU migration, the UE served by the source logical DU needs to be handed over to another cell. According to relevant technologies, the source donor-CU can determine the target cell to which the UE should be handed over based on the UE's measurement report results of neighboring cells. When the cell of the source logical DU and the cell of the target logical DU use different downlink frequencies, the cell of the source logical DU and the cell of the target logical DU can be activated at the same time. Therefore, when the target logical DU cell is activated, the UE can still be connected to the source logical DU. The UE can measure the signal quality of the target logical DU cell and report it to the source donor-CU, so that the source donor-CU determines to hand over the UE to the target logical DU cell. However, when the cell of the source logical DU and the cell of the target logical DU use the same downlink frequency, the cell of the source logical DU and the cell of the target logical DU cannot be activated at the same time. Therefore, the UE served by the source logical DU cannot measure the signal quality of the target logical DU cell, resulting in the original donor-CU being unable to determine the target cell for the UE to hand over.

[0210] Question 2: With LTE RACH-less handover, the target base station determines whether to perform RACH-less handover for the UE based on the Operation Administration and Maintenance (OAM) configuration, for example, the source and target cell identifiers configured by OAM to allow RACH-less handover. If RACH-less handover is performed, the target base station configures the timing advance (TA) used by the UE to send the initial uplink message in the target cell, as well as a type 1 configured grant (CG) physical uplink shared channel (PUSCH) resource pre-configured for the initial uplink transmission, in the UE's handover command. Alternatively, the target cell dynamically schedules the UE's PUSCH transmission using the physical downlink control channel (PDCCH). During handover, the UE skips the random access procedure and transmits the initial uplink message in the target cell using the TA configured in the handover command and the pre-configured PUSCH resources or PUSCH resources dynamically scheduled by the PDCCH. However, unlike LTE RACH-less handover, in NR RACH-less handover, the UE needs to select a beam to use when handing over to the target cell. Related technologies do not address the issue of how the UE selects a beam for RACH-less handover.

[0211] Based on the above technical problems, the embodiments of the present disclosure propose a switching method, device and storage medium, in which the source logical DU of the mobile IAB node reports the relevant information of the target logical DU cell of the mobile IAB node to the source donor-CU of the source logical DU of the mobile IAB node, so that the source donor-CU of the source logical DU of the mobile IAB node promptly obtains the target cell for UE switching, thereby realizing the switching of the UE between IAB logical DUs.

[0212] To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present disclosure without making any creative efforts shall fall within the scope of protection of the present disclosure.

[0213] FIG8 is a flowchart of a handover method according to an embodiment of the present disclosure. As shown in FIG8 , an embodiment of the present disclosure provides a handover method, the execution subject of which may be a source donor-CU of a source logical DU of a mobile IAB node. The method includes:

[0214] Step 801: Obtain relevant information of the target logical DU cell of the mobile IAB node.

[0215] Specifically, in the embodiment of the present disclosure, the source logical DU of the mobile IAB node reports the relevant information of the target logical DU cell of the mobile IAB node to the source donor-CU of the source logical DU of the mobile IAB node.

[0216] The related information is used to hand over the UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node.

[0217] The source donor-CU of the source logical DU of the mobile IAB node obtains the relevant information of the target logical DU cell of the mobile IAB node.

[0218] For example, the source donor-CU of the source logical DU of the mobile IAB node obtains the relevant information sent by the source logical DU of the mobile IAB node through an F1 interface application protocol (F1 Application Protocol, F1AP) message.

[0219] For example, the source donor-CU of the source logical DU of the mobile IAB node obtains the relevant information sent by the source logical DU of the mobile IAB node through a distribution unit configuration update (GNB-DU CONFIGURATION UPDATE) message.

[0220] In some embodiments, the relevant information includes one or more of the following information:

[0221] Identification information of the target logical DU cell;

[0222] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0223] Downlink frequency information of the target logical DU cell;

[0224] Measurement reference signal configuration information of the target logical DU cell.

[0225] Step 802: Hand over the user equipment UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node based on the relevant information.

[0226] Specifically, in an embodiment of the present disclosure, after the source donor-CU of the source logical DU of the mobile IAB node obtains relevant information of the target logical DU cell of the mobile IAB node, the UE served by the mobile IAB node is switched from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node based on the relevant information.

[0227] In some embodiments, the switching, based on the relevant information, of the UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node includes:

[0228] Configuring the UE to measure the target logical DU cell;

[0229] Determine a target logical DU cell for handing over the UE to the mobile IAB node based on the measurement result.

[0230] Specifically, in an embodiment of the present disclosure, if the target logical DU cell and its co-located source logical DU cell have different downlink frequencies, the source donor-CU may configure the UE to measure the target logical DU cell based on the measurement reference signal configuration information of the target logical DU cell reported by the IAB node. The source donor-CU determines to hand over the UE served by the mobile IAB node to the target logical DU cell based on the UE's measurement results of the target logical DU cell. The source donor-CU may also determine to hand over the UE to the target logical DU cell based on the co-location relationship between the target logical DU cell and the source logical DU cell.

[0231] In some embodiments, the switching, based on the relevant information, of the UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node includes:

[0232] Determine to hand over the UE to the target logical DU cell based on the correspondence or co-location relationship between the target logical DU cell and the source logical DU cell.

[0233] Specifically, in the embodiment of the present disclosure, if the target logical DU cell and the co-located source logical DU cell have the same downlink frequency, the source donor-CU cannot obtain the UE's measurement results for the target logical DU cell because the target logical DU cell and the source logical DU cell cannot operate at the same time. The source donor-CU can only determine to hand over the UE served by the mobile IAB node from the source logical DU cell to the target logical DU cell based on the co-location relationship between the target logical DU cell and the source logical DU cell.

[0234] In some embodiments, the downlink frequency of the target logical DU cell and the source logical DU cell may be the same, or the downlink frequency of the target logical DU cell and the source logical DU cell may be different.

[0235] In some embodiments, the method further comprises:

[0236] receiving a handover command for the UE from a target donor-CU of a target logical DU of the mobile IAB node;

[0237] The handover command is sent to the UE.

[0238] Specifically, in the embodiment of the present disclosure, a source donor-CU of a source logical DU of a mobile IAB node receives a handover command for a UE from a target donor-CU of a target logical DU of the mobile IAB node.

[0239] Then the source donor-CU of the source logical DU of the mobile IAB node sends the handover command to the UE.

[0240] The source donor-CU of the source logical DU of the mobile IAB node can determine whether the downlink frequency of the target logical DU cell is the same as that of the co-located source logical DU cell. If an Xn interface exists between the source donor-CU and the target donor-CU, the source donor-CU can obtain the target logical DU cell information through the XnAP. This method is not affected by the Xn interface, that is, when there is no Xn interface between the source donor-CU and the target donor-CU, the source donor-CU can obtain the target logical DU cell information.

[0241] The handover method provided by the present disclosure reports the relevant information of the target logical DU cell of the mobile IAB node to the source donor-CU of the source logical DU of the mobile IAB node, so that the source donor-CU of the source logical DU of the mobile IAB node promptly obtains the target cell to which the UE is switched, thereby realizing the handover of the UE between IAB logical DUs.

[0242] FIG9 is a second flow chart of a handover method provided by an embodiment of the present disclosure. As shown in FIG9 , an embodiment of the present disclosure provides a handover method, the execution subject of which may be a mobile IAB node, etc. The method includes:

[0243] Step 901: Send relevant information of the target logical DU cell of the mobile IAB node; the relevant information is used to switch the UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node.

[0244] Specifically, in the embodiment of the present disclosure, the source logical DU of the mobile IAB node reports the relevant information of the target logical DU cell of the mobile IAB node to the source donor-CU of the source logical DU of the mobile IAB node.

[0245] The related information is used to hand over the UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node.

[0246] The source donor-CU of the source logical DU of the mobile IAB node obtains the relevant information of the target logical DU cell of the mobile IAB node.

[0247] The handover method provided by the present disclosure reports the relevant information of the target logical DU cell of the mobile IAB node to the source donor-CU of the source logical DU of the mobile IAB node, so that the source donor-CU of the source logical DU of the mobile IAB node promptly obtains the target cell to which the UE is switched, thereby realizing the handover of the UE between IAB logical DUs.

[0248] In some embodiments, the method further comprises:

[0249] Determine a beam for the UE to perform RACH-less handover in the target logical DU cell;

[0250] Configuring a synchronization signal block SSB corresponding to the beam and a configuration authorization CG physical uplink shared channel PUSCH resource for the SSB; the PUSCH resource is used by the UE to send an initial uplink message of RACH-less switching to the target logical DU cell;

[0251] The first configuration information is sent to the target donor-CU of the target logical DU of the mobile IAB node through an F1AP message, wherein the first configuration information is used to indicate the SSB corresponding to the beam and the CG PUSCH resources for the SSB.

[0252] Specifically, in the embodiment of the present disclosure, the target logical DU of the mobile IAB node also needs to determine the beam for the UE to perform RACH-less switching in the target logical DU cell, and directly pre-configure the synchronization signal block (SSB) corresponding to the beam and the CG PUSCH resources for the SSB.

[0253] After the target logical DU of the mobile IAB node determines the beam for the UE to perform RACH-less handover in the target logical DU cell, it configures the SSB corresponding to the beam and the CG PUSCH resource for the SSB. The PUSCH resource is used by the UE to send the initial uplink message of the RACH-less handover to the target logical DU cell.

[0254] The target logical DU of the mobile IAB node sends the SSB corresponding to the beam and the CG PUSCH resources for the SSB to the target donor-CU of the target logical DU of the mobile IAB node.

[0255] For example, the target logical DU of the mobile IAB node can send an F1AP message to the target donor-CU of the target logical DU of the mobile IAB node. The F1AP message carries first configuration information, and the first configuration information is used to indicate the SSB corresponding to the beam and the CG PUSCH resources for the SSB.

[0256] For example, the target logical DU of the mobile IAB node determines the SSB for the UE to perform RACH-less switching and pre-configures the type 1 CG PUSCH resource corresponding to the SSB. The target logical DU of the mobile IAB node generates a reconfiguration synchronization (ReconfigurationWithSync) message containing the pre-configured PUSCH resource information for the SSB and sends it to the UE through a switching command. The UE receives the switching command containing ReconfigurationWithSync. ReconfigurationWithSync contains the pre-configured PUSCH resource. The UE selects the SSB corresponding to the pre-configured PUSCH resource and uses the PUSCH resource and the TA of the source logical DU cell to send an initial uplink message to the target logical DU cell of the mobile IAB node.

[0257] In the embodiment of the present disclosure, the preconfigured PUSCH resources in the handover command are bound to the SSB, and the network can obtain the SSB selected by the UE through the PUSCH selected by the UE according to the preconfigured PUSCH resources. Therefore, even if the RACH process is skipped, the initial SSB selection in the target cell of the handover can be achieved.

[0258] The handover method provided by the present disclosure reports the relevant information of the target logical DU cell of the mobile IAB node to the source donor-CU of the source logical DU of the mobile IAB node, so that the source donor-CU of the source logical DU of the mobile IAB node promptly obtains the target cell to which the UE is switched, thereby realizing the handover of the UE between IAB logical DUs.

[0259] In some embodiments, the method further comprises:

[0260] Determining a beam for the UE to perform RACH-less handover in the target logical DU cell;

[0261] The physical downlink control channel PDCCH associated with the SSB corresponding to the beam is used to dynamically schedule the UE to use the authorized PUSCH resources; the PUSCH resources are used by the UE to send an initial uplink message to the target logical DU cell.

[0262] Specifically, in the embodiment of the present disclosure, the target logical DU of the mobile IAB node also needs to determine the beam for the UE to perform RACH-less switching in the target logical DU cell, and dynamically schedule the UE to use the authorized PUSCH resources through the PDCCH.

[0263] After the target logical DU of the mobile IAB node determines the beam for the UE to perform RACH-less handover in the target logical DU cell, it uses the PDCCH associated with the SSB corresponding to the beam to dynamically schedule the UE to use the authorized PUSCH resources. The PUSCH resources are used by the UE to send the initial uplink message of the RACH-less handover to the target logical DU cell.

[0264] For example, the target logical DU of the mobile IAB node determines the SSB for the UE to perform RACH-less handover, and uses the PDCCH corresponding to the SSB to dynamically schedule the UE's PUSCH transmission. The target logical DU of the mobile IAB node generates ReconfigurationWithSync information and sends it to the UE through a handover command. The UE receives the handover command containing ReconfigurationWithSync. ReconfigurationWithSync does not include pre-configured type 1 CG PUSCH resources. The UE detects the PDCCH of the target logical DU cell, selects the SSB corresponding to the PDCCH that schedules the UE, and uses the PUSCH resources scheduled by the PDCCH and the TA of the source logical DU cell to send an initial uplink message to the target logical DU cell.

[0265] The handover method provided by the present disclosure reports the relevant information of the target logical DU cell of the mobile IAB node to the source donor-CU of the source logical DU of the mobile IAB node, so that the source donor-CU of the source logical DU of the mobile IAB node promptly obtains the target cell to which the UE is switched, thereby realizing the handover of the UE between IAB logical DUs.

[0266] In some embodiments, the switching command further includes second configuration information, and the second configuration information is used to instruct the UE to select the SSB receiving power threshold used by SSB.

[0267] For example, the pre-configured PUSCH resource information for SSB includes an SSB receiving power threshold indicating that the UE selects SSB for use.

[0268] Specifically, when the target logical DU of the mobile IAB node is configured with the SSB corresponding to the beam and the CG PUSCH resources for the SSB, the UE selects the SSB with a receiving power higher than the SSB receiving power threshold from the SSB indicated in the first configuration information as the SSB corresponding to the beam for RACH-less switching in the target cell.

[0269] When the target logical DU of the mobile IAB node dynamically schedules the UE to use the authorized PUSCH resources through PDCCH, the UE selects the SSB whose receiving power corresponding to the PDCCH is higher than the SSB receiving power threshold as the SSB corresponding to the beam for RACH-less switching in the target cell.

[0270] In the disclosed embodiment, the PUSCH dynamically scheduled by the PDCCH is bound to the SSB, so that the network can learn the SSB selected by the UE through the PUSCH sent by the UE. Therefore, even if the RACH process is skipped, the initial SSB selection in the target cell of the handover can be achieved.

[0271] The handover method provided by the present disclosure reports the relevant information of the target logical DU cell of the mobile IAB node to the source donor-CU of the source logical DU of the mobile IAB node, so that the source donor-CU of the source logical DU of the mobile IAB node promptly obtains the target cell to which the UE is switched, thereby realizing the handover of the UE between IAB logical DUs.

[0272] In some embodiments, determining a beam for the UE to perform RACH-less handover in the target logical DU cell includes:

[0273] The beam for the UE to perform RACH-less switching in the target logical DU is determined based on the measurement result of the UE on the target logical DU cell included in the switching preparation information.

[0274] Specifically, in the embodiment of the present disclosure, the target logical DU of the mobile IAB node determines the beam for the UE to perform RACH-less handover in the target logical DU based on the UE's measurement result on the target logical DU cell included in the handover preparation information.

[0275] For example, the target logical DU of the mobile IAB node determines the SSB for the UE to perform RACH-less handover based on the cell measurement result (measurement result for SSB / CSI-RS) in the handover preparation information.

[0276] The handover method provided by the present disclosure reports the relevant information of the target logical DU cell of the mobile IAB node to the source donor-CU of the source logical DU of the mobile IAB node, so that the source donor-CU of the source logical DU of the mobile IAB node promptly obtains the target cell to which the UE is switched, thereby realizing the handover of the UE between IAB logical DUs.

[0277] In some embodiments, determining a beam for the UE to perform RACH-less handover in the target logical DU cell includes:

[0278] Determine a beam used by the UE in the source logical DU cell;

[0279] The beam used by the UE for RACH-less handover in the target logical DU cell is determined based on the beam used by the UE in the source logical DU cell.

[0280] Specifically, in an embodiment of the present disclosure, the target logical DU of the mobile IAB node first determines the beam used by the UE in the source logical DU cell, and then, based on the correspondence or quasi-co-location relationship between the beam of the source logical DU cell and the beam of the target logical DU cell, determines the beam for the UE to perform RACH-less switching in the target logical DU cell.

[0281] For example, the target logical DU of the mobile IAB node determines the SSB for the UE to perform RACH-less handover based on the beam used by the UE in the source logical DU cell and the quasi-co-location relationship between the SSB of the logical DU cell and the SSB of the target logical DU cell.

[0282] For another example, the target logical DU of the mobile IAB node determines the SSB for the UE to perform RACH-less switching based on the beam used by the UE in the source logical DU cell and the correspondence between the SSB of the logical DU cell and the SSB of the target logical DU cell.

[0283] The handover method provided by the present disclosure reports the relevant information of the target logical DU cell of the mobile IAB node to the source donor-CU of the source logical DU of the mobile IAB node, so that the source donor-CU of the source logical DU of the mobile IAB node promptly obtains the target cell to which the UE is switched, thereby realizing the handover of the UE between IAB logical DUs.

[0284] FIG10 is a third flow chart of a handover method provided by an embodiment of the present disclosure. As shown in FIG10 , an embodiment of the present disclosure provides a handover method, the execution subject of which may be a UE, such as a mobile phone. The method includes:

[0285] Step 1001: Determine the PUSCH resources of the SSB corresponding to the beam for RACH-less handover in the target cell.

[0286] Step 1002: Use the PUSCH resources to send an initial uplink message to the target cell.

[0287] Specifically, when the target logical DU of the mobile IAB node directly pre-configures the SSB corresponding to the beam and the CG PUSCH resource for the SSB through a switching command, the UE selects the SSB corresponding to the pre-configured PUSCH resource, and uses the PUSCH resource and the TA of the source logical DU cell to send an initial uplink message to the target logical DU cell of the mobile IAB node.

[0288] When the target logical DU of the mobile IAB node dynamically schedules the UE to use the authorized PUSCH resources through PDCCH, the UE detects the PDCCH of the target logical DU cell, selects the SSB corresponding to the PDCCH that schedules the UE, and uses the PUSCH resources scheduled by the PDCCH and the TA of the source logical DU cell to send an initial uplink message to the target logical DU cell.

[0289] In the switching method provided by the present disclosure, the UE determines the PUSCH resource of the SSB corresponding to the beam for RACH-less switching in the target cell, and uses the PUSCH resource to send an initial uplink message to the target cell. This method directly selects the PUSCH resource corresponding to the SSB to access the target cell, eliminating the random access process and reducing the switching delay.

[0290] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less handover in the target cell includes:

[0291] Receiving a handover command sent by a network device; the handover command includes first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB;

[0292] Based on the first configuration information, the SSB corresponding to the beam for RACH-less switching in the target cell is selected and the PUSCH resources for the SSB are determined.

[0293] Specifically, in the embodiment of the present disclosure, the target logical DU of the mobile IAB node directly pre-configures the SSB corresponding to the beam and the CG PUSCH resources for the SSB through a handover command.

[0294] The UE receives a switching command sent by a network device, where the switching command includes first configuration information, where the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less switching in the target cell and the CG PUSCH resources for the SSB.

[0295] Based on the first configuration information, the UE selects the SSB corresponding to the beam for RACH-less switching in the target cell and determines the PUSCH resources for the SSB, and uses the PUSCH resources and the TA of the source logical DU cell to send an initial uplink message to the target logical DU cell of the mobile IAB node.

[0296] In the switching method provided by the present disclosure, the UE determines the PUSCH resource of the SSB corresponding to the beam for RACH-less switching in the target cell, and uses the PUSCH resource to send an initial uplink message to the target cell. This method directly selects the PUSCH resource corresponding to the SSB to access the target cell, eliminating the random access process and reducing the switching delay.

[0297] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less handover in the target cell includes:

[0298] receiving a handover command sent by a network device; the handover command does not include first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB;

[0299] Determine that the SSB corresponding to the PDCCH used by the target cell to schedule the UE is the SSB corresponding to the beam for performing RACH-less switching in the target cell, detect the PDCCH used by the target cell to schedule the UE; and determine the PUSCH resources scheduled by the PDCCH.

[0300] Specifically, in the embodiment of the present disclosure, the target logical DU of the mobile IAB node dynamically schedules the UE to use the authorized PUSCH resources through the PDCCH.

[0301] The UE receives the handover command sent by the network device, then detects the PDCCH of the target logical DU cell, selects the SSB corresponding to the PDCCH as the SSB corresponding to the beam for RACH-less handover in the target cell, and determines the PUSCH resources scheduled by the PDCCH. Finally, the UE uses the PUSCH resources scheduled by the PDCCH and the TA of the source logical DU cell to send an initial uplink message to the target logical DU cell.

[0302] In the switching method provided by the present disclosure, the UE determines the PUSCH resource of the SSB corresponding to the beam for RACH-less switching in the target cell, and uses the PUSCH resource to send an initial uplink message to the target cell. This method directly selects the PUSCH resource corresponding to the SSB to access the target cell, eliminating the random access process and reducing the switching delay.

[0303] In some embodiments, the handover command further includes second configuration information, where the second configuration information is used to indicate to the UE an SSB receiving power threshold for selecting SSB;

[0304] The selecting the SSB corresponding to the beam for performing RACH-less switching in the target cell includes:

[0305] Selecting an SSB with a reception power higher than the SSB reception power threshold from among the SSBs indicated in the first configuration information as the SSB corresponding to the beam for RACH-less switching in the target cell; or,

[0306] The SSB whose receiving power corresponding to the PDCCH is higher than the SSB receiving power threshold is selected as the SSB corresponding to the beam for RACH-less switching in the target cell.

[0307] Specifically, in an embodiment of the present disclosure, the switching command also includes second configuration information, and the second configuration information is used to instruct the UE to select the SSB receiving power threshold used by the SSB.

[0308] When the target logical DU of the mobile IAB node is configured with the SSB corresponding to the beam and the CG PUSCH resources for the SSB, the UE selects the SSB with a receiving power higher than the SSB receiving power threshold from the SSB indicated in the first configuration information as the SSB corresponding to the beam for RACH-less switching in the target cell.

[0309] When the target logical DU of the mobile IAB node dynamically schedules the UE to use the authorized PUSCH resources through PDCCH, the UE selects the SSB whose receiving power corresponding to the PDCCH is higher than the SSB receiving power threshold as the SSB corresponding to the beam for RACH-less switching in the target cell.

[0310] In the embodiments of the present disclosure, the UE can select an SSB with better reception quality from multiple pre-configured SSBs or multiple dynamically scheduled SSBs, thereby improving reliability.

[0311] In the switching method provided by the present disclosure, the UE determines the PUSCH resource of the SSB corresponding to the beam for RACH-less switching in the target cell, and uses the PUSCH resource to send an initial uplink message to the target cell. This method directly selects the PUSCH resource corresponding to the SSB to access the target cell, eliminating the random access process and reducing the switching delay.

[0312] In some embodiments, the method further comprises:

[0313] If the receiving power of all SSBs indicated in the first configuration information is lower than the SSB receiving power threshold, or the receiving power threshold of the SSBs corresponding to all detected PDCCHs is lower than the SSB receiving power threshold, a random access process is initiated to access the target cell.

[0314] Specifically, when the target logical DU of the mobile IAB node is configured with the SSB corresponding to the beam and the CG PUSCH resources for the SSB, the receiving power of all SSBs indicated in the first configuration information is lower than the SSB receiving power threshold, that is, the SSB indicated in the first configuration information does not meet the threshold requirements. The UE can fall back to access the target logical DU cell using the random access process.

[0315] When the target logical DU of the mobile IAB node dynamically schedules the UE to use the authorized PUSCH resources through PDCCH, the receiving power threshold of the SSB corresponding to all detected PDCCHs is lower than the SSB receiving power threshold, that is, the UE detects the PDCCH of the target logical DU cell and the received reference signal receiving power (RSRP) of the SSB corresponding to the PDCCH does not meet the threshold requirement of the SSB, the UE can fall back to using the random access process to access the target logical DU cell.

[0316] In the embodiment of the present disclosure, when there is no SSB that meets the threshold requirement, the UE can fall back to accessing the target logical DU cell using a random access procedure, thereby ensuring that the handover can be completed and further improving reliability.

[0317] In the switching method provided by the present disclosure, the UE determines the PUSCH resource of the SSB corresponding to the beam for RACH-less switching in the target cell, and uses the PUSCH resource to send an initial uplink message to the target cell. This method directly selects the PUSCH resource corresponding to the SSB to access the target cell, eliminating the random access process and reducing the switching delay.

[0318] The method in the above embodiment is further illustrated below with several specific examples.

[0319] Example 1: When the source and target logical DU cells of a mobile IAB node use different downlink frequencies, the source donor-CU of the IAB-DU determines to hand over the UE served by the mobile IAB node from the source logical DU cell to the target logical DU cell based on the UE's measurement results on the target logical DU cell. The target logical DU determines the beam for the UE to perform RACH-less handover based on the UE's measurement results on the target logical DU cell.

[0320] FIG11 is a schematic diagram of a switching principle according to an embodiment of the present disclosure. As shown in FIG11 , the switching process may include the following steps:

[0321] Step 1: After the target logical DU establishes an F1 connection with the target donor-CU, the source logical DU reports the relevant information of the target logical DU cell to the source donor-CU through the F1AP message (for example, through the GNB-DU CONFIGURATION UPDATE message). This information can indicate the source logical DU cell co-located with the target logical DU cell, and the downlink frequency information of the target logical DU cell. Among them, the target logical DU and the source logical DU can control one or more cells, and one target logical DU cell can correspond to one or more co-located source logical DU cells, or multiple target logical DU cells correspond to one co-located source logical DU cell. The source donor-CU can learn from the above information that the downlink frequency of the target logical DU cell and the co-located source logical DU cell are different, so that the source donor-CU can configure the UE to measure the target logical DU cell. The source donor-CU determines to switch the UE served by the mobile IAB node to the target logical DU cell based on the UE's measurement results of the target logical DU cell.

[0322] Step 2: The source donor-CU includes the measurement results of the target logical DU cell reported by the UE (including cell-level and SSB / CSI-RS measurement results) in the radio resource management (RRM) configuration of the handover preparation information (HandoverPreparationInformation) of the handover request (HANDOVER REQUEST) message and sends it to the target donor-CU.

[0323] Step 3: After allocating resources to the UE, the target donor-CU forwards the Handover Preparation Information (HandoverPreparationInformation) to the target logical DU using a UE CONTEXT SETUP REQUEST message. The target logical DU determines that the source and target cells are co-located based on the source cell identifier in the Handover Preparation message and the target cell identifier in the UE CONTEXT SETUP REQUEST message. If the uplink frequencies of the source and target cells meet the condition of belonging to the same Timing Advance Group (TAG), the UE is eligible for RACH-less handover.

[0324] The target logical DU then determines the SSB for the UE to perform RACH-less switching based on the cell measurement results (measurement results for SSB / CSI-RS) in the handover preparation information, and pre-configures the type 1 CG PUSCH resources corresponding to the SSB (optionally, also sets the RSRP threshold for the UE to select the SSB), or uses the PDCCH corresponding to the SSB to dynamically schedule the UE's PUSCH transmission.

[0325] Step 4: The target logical DU generates a CellGroupConfig information element containing the ReconfigurationWithSync message and sends it to the target donor-CU via a UE CONTEXT SETUP RESPONSE message. The ReconfigurationWithSync message indicates the use of the source cell TA for RACH-less handover and may also include type 1 CG PUSCH resource information corresponding to the SSB pre-configured for RACH-less handover.

[0326] Step 5: The target donor-CU generates a handover command, which includes the CellGroupConfig information unit sent by the target logical DU, and sends the handover command to the source donor-CU in a handover request response (HANDOVER REQUEST ACKNOWLEDGE) message.

[0327] Step 6: The source donor-CU forwards the handover command to the source logical DU in a UE CONTEXT MODIFICATION message.

[0328] Step 7: The source logical DU sends a handover command (RRCReconfiguration) to the UE. If ReconfigurationWithSync includes a pre-configured type 1 CG PUSCH resource, the UE selects the SSB corresponding to the pre-configured PUSCH resource and uses the PUSCH resource and the TA of the source logical DU cell to send an initial uplink message to the target logical DU cell. Optionally, the UE selects an SSB in the pre-configured resource whose received RSRP meets the threshold requirement.

[0329] If ReconfigurationWithSync does not include pre-configured type 1 CG PUSCH resources, the UE detects the PDCCH of the target logical DU cell, selects the SSB corresponding to the PDCCH that schedules the UE, and uses the PUSCH resources scheduled by the PDCCH and the TA of the source logical DU cell to send an initial uplink message to the target logical DU cell. Optionally, if the UE detects the PDCCH of the target logical DU cell and the received RSRP of the SSB corresponding to the PDCCH meets the threshold requirement, the UE selects the SSB corresponding to the PDCCH. If no SSB meets the threshold requirement, the UE can fall back to accessing the target logical DU cell using the random access procedure.

[0330] Example 2: When the source and target logical DU cells of a mobile IAB node use the same downlink frequency, the source donor-CU of the IAB-DU determines to hand over the UE served by the mobile IAB node from the source logical DU cell to the target logical DU cell based on the co-location relationship between the target and source logical DU cells. The target logical DU determines the beam for the UE to perform RACH-less handover based on the UE's measurement results of the source logical DU cell.

[0331] FIG12 is a second schematic diagram of a switching principle provided by an embodiment of the present disclosure. As shown in FIG12 , the switching process may include the following steps:

[0332] Step 1: After the target logical DU establishes an F1 connection with the target donor-CU, the source logical DU reports relevant information of the target logical DU cell to the source donor-CU through an F1AP message (for example, through a GNB-DU CONFIGURATION UPDATE message). This information can indicate the source logical DU cell co-located with the target logical DU cell, as well as the downlink frequency information of the target logical DU cell. Among them, the target logical DU and the source logical DU can control one or more cells, and one target logical DU cell can correspond to one or more co-located source logical DU cells, or multiple target logical DU cells correspond to one co-located source logical DU cell. The source donor-CU can learn from the above information that the downlink frequency of the target logical DU cell and the co-located source logical DU cell are the same, so that the source donor-CU can know that the UE's measurement results for the target logical DU cell cannot be obtained. The source donor-CU can only determine to switch the UE served by the mobile IAB node from the source logical DU cell to the target logical DU cell based on the co-location relationship between the target logical DU cell and the source logical DU cell.

[0333] Step 2: The source donor-CU includes the measurement results of the source logical DU cell reported by the UE (including cell-level and SSB / CSI-RS measurement results) in the RRM configuration of the handover preparation information (HandoverPreparationInformation) of the handover request message and sends it to the target donor-CU.

[0334] Step 3: After allocating resources to the UE, the target donor-CU forwards the Handover Preparation Information (HandoverPreparationInformation) to the target logical DU using a UE Context Setup Request message. The target logical DU determines that the source and target cells are co-located based on the source cell identifier in the Handover Preparation message and the target cell identifier in the UE Context Setup Request message. If the uplink frequencies of the source and target cells meet the condition of belonging to the same TAG, the UE is eligible for RACH-less handover.

[0335] The target logical DU then obtains an equivalent target logical DU cell measurement result based on the source logical DU cell measurement result (SSB / CSI-RS measurement result) in the handover preparation information and the quasi-co-location relationship between the SSB of the source logical DU cell and the SSB of the target logical DU cell. For example, in the figure below, if SSB#a of the source logical DU cell and SSB#b of the target logical DU cell are quasi-co-located, the measurement result of SSB#a of the source logical DU cell is used as the measurement result of SSB#b of the target logical DU cell.

[0336] Based on the measurement results of the equivalent target logical DU cell, determine the SSB for the UE to perform RACH-less switching, and pre-configure the type 1 CG PUSCH resources corresponding to the SSB (optionally, also including the RSRP threshold for the UE to select the SSB), or use the PDCCH corresponding to the SSB to dynamically schedule the UE's PUSCH transmission.

[0337] Step 4: The target logical DU generates a CellGroupConfig information element containing ReconfigurationWithSync and sends it to the target donor-CU via a UE Context Setup Response message. ReconfigurationWithSync indicates the use of the source cell TA for RACH-less handover and may also include type 1 CG PUSCH resource information corresponding to the SSB pre-configured for RACH-less handover of the UE.

[0338] Step 5: The target donor-CU generates a handover command, which includes the CellGroupConfig information element sent by the target logical DU, and sends the handover command to the source donor-CU in a handover request response message.

[0339] Step 6: The source donor-CU forwards the handover command to the source logical DU in a UE Context Modification Request message. At the same time, it instructs the source logical DU to activate the target logical DU cell and deactivate the source logical DU cell after sending the handover command to the UE.

[0340] Step 7: The source logical DU sends a handover command to the UE. If ReconfigurationWithSync includes a preconfigured type 1 CG PUSCH resource, the UE selects the SSB corresponding to the preconfigured PUSCH resource and uses the PUSCH resource and the TA of the source logical DU cell to send an initial uplink message to the target logical DU cell. Optionally, the UE selects an SSB in the preconfigured resource whose received RSRP meets the threshold requirement.

[0341] If ReconfigurationWithSync does not include pre-configured PUSCH resources, the UE detects the PDCCH of the target logical DU cell, selects the SSB corresponding to the PDCCH that schedules the UE, and uses the PUSCH resources scheduled by the PDCCH and the TA of the source logical DU cell to send an initial uplink message to the target logical DU cell. Optionally, the UE detects the PDCCH of the target logical DU cell and if the received RSRP of the SSB corresponding to the PDCCH meets the threshold requirement, the UE selects the SSB corresponding to the PDCCH. If there is no SSB that meets the threshold requirement, the UE can fall back to accessing the target logical DU cell using the random access procedure.

[0342] Example 3: When the source and target logical DU cells of a mobile IAB node use the same downlink frequency, the source donor-CU of the IAB-DU determines to hand over the UE served by the mobile IAB node from the source logical DU cell to the target logical DU cell based on the co-location relationship between the target and source logical DU cells. The target logical DU determines the beam used by the UE for RACH-less handover based on the beam used by the UE in the source logical DU cell.

[0343] The switching process may include the following steps:

[0344] Step 1: After the target logical DU establishes an F1 connection with the target donor-CU, the source logical DU reports relevant information of the target logical DU cell to the source donor-CU through the F1AP message (for example, through the GNB-DU CONFIGURATION UPDATE message). This information can indicate the source logical DU cell co-located with the target logical DU cell, as well as the downlink frequency information of the target logical DU cell. The source donor-CU can learn from the above information that the downlink frequency of the target logical DU cell and the co-located source logical DU cell are the same. In this way, the source donor-CU knows that it cannot obtain the UE's measurement results for the target logical DU cell, and can only determine to switch the UE served by the mobile IAB node from the source logical DU cell to the target logical DU cell based on the co-location relationship between the target logical DU cell and the source logical DU cell.

[0345] Step 2: The source donor-CU includes the UE's identity in the source logical DU cell (e.g., Cell Radio Network Temporary Identity (C-RNTI)) or the identity in the source logical DU (e.g., gNB-DU UE F1AP ID) in the handover request message and sends it to the target donor-CU.

[0346] Step 3: After allocating resources to the UE, the target donor-CU forwards the UE's identity in the source logical DU cell (e.g., C-RNTI) or the identity in the source logical DU (e.g., gNB-DU UE F1AP ID) to the target logical DU using a UE CONTEXT SETUP REQUEST message. The target logical DU determines that the source and target cells are co-located based on the source cell identity in the HANDOVER PREPARE message and the target cell identity in the UE CONTEXT SETUP REQUEST message. If the uplink frequencies of the source and target cells meet the same TAG condition, the UE is eligible for RACH-less handover.

[0347] The target logical DU then obtains the beam used by the UE in the source logical DU cell based on the UE's identifier in the source logical DU cell (e.g., C-RNTI) or the identifier in the source logical DU (e.g., gNB-DU UE F1AP ID). It then determines the beam used by the UE in the target logical DU cell based on the quasi-co-location relationship between the SSBs in the source logical DU cell and the SSBs in the target logical DU cell. For example, if SSB#a of the source logical DU cell and SSB#b of the target logical DU cell are quasi-co-located, and if the UE uses SSB#a in the source logical DU cell, the UE is determined to use SSB#b in the target logical DU cell. The target logical DU pre-configures the PUSCH resources corresponding to the SSB (optionally, including the RSRP threshold for the UE to select the SSB) or uses the PDCCH corresponding to the SSB to dynamically schedule the UE's PUSCH transmission.

[0348] Step 4: The target logical DU generates a CellGroupConfig information element containing ReconfigurationWithSync and sends it to the target donor-CU via a UE Context Setup Response message. ReconfigurationWithSync indicates the use of the source cell TA for RACH-less handover and may also include PUSCH resource information corresponding to the SSB pre-configured for RACH-less handover of the UE.

[0349] Step 5: The target donor-CU generates a handover command, which includes the CellGroupConfig information element sent by the target logical DU, and sends the handover command to the source donor-CU in a handover request response message.

[0350] Step 6: The source donor-CU forwards the handover command to the source logical DU in a UE Context Modification Request message. At the same time, it instructs the source logical DU to activate the target logical DU cell and deactivate the source logical DU cell after sending the handover command to the UE.

[0351] Step 7: The source logical DU sends a handover command to the UE. If ReconfigurationWithSync includes a preconfigured PUSCH resource, the UE selects the SSB corresponding to the preconfigured PUSCH resource and uses the PUSCH resource and the TA of the source logical DU cell to send an initial uplink message to the target logical DU cell. Optionally, the UE selects an SSB in the preconfigured resource whose received RSRP meets the threshold requirement.

[0352] If ReconfigurationWithSync does not include pre-configured PUSCH resources, the UE detects the PDCCH of the target logical DU cell, selects the SSB corresponding to the PDCCH that schedules the UE, and uses the PUSCH resources scheduled by the PDCCH and the TA of the source logical DU cell to send an initial uplink message to the target logical DU cell. Optionally, the UE detects the PDCCH of the target logical DU cell and if the received RSRP of the SSB corresponding to the PDCCH meets the threshold requirement, the UE selects the SSB corresponding to the PDCCH. If no SSB meets the threshold requirement, it means that the candidate SSB selected for the UE is not suitable. In order to avoid beam failure, the UE can fall back to accessing the target logical DU cell using the random access procedure.

[0353] FIG13 is a schematic diagram of the structure of a source donor-CU of a source logical DU of a mobile IAB node provided by an embodiment of the present disclosure. As shown in FIG13 , the network device includes a memory 1320, a transceiver 1300, and a processor 1310, wherein:

[0354] The memory 1320 is used to store computer programs; the transceiver 1300 is used to send and receive data under the control of the processor 1310; the processor 1310 is used to read the computer program in the memory 1320 and perform the following operations:

[0355] Obtaining relevant information of a target logical DU cell of the mobile IAB node;

[0356] Hand over the UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node based on the relevant information.

[0357] In FIG13 , the bus architecture may include any number of interconnected buses and bridges, specifically various circuits linked together by one or more processors represented by processor 1310 and memory represented by memory 1320. The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface. The transceiver 1300 may be a plurality of components, namely, a transmitter and a receiver, providing a unit for communicating with various other devices over a transmission medium, such as a wireless channel, a wired channel, an optical cable, and the like. The processor 1310 is responsible for managing the bus architecture and general processing, and the memory 1320 may store data used by the processor 1310 when performing operations.

[0358] The processor 1310 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or a complex programmable logic device (CPLD). The processor may also adopt a multi-core architecture.

[0359] In some embodiments, the switching, based on the relevant information, of the UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node includes:

[0360] Configuring the UE to measure the target logical DU cell;

[0361] Determine a target logical DU cell for handing over the UE to the mobile IAB node based on the measurement result.

[0362] In some embodiments, the switching, based on the relevant information, of the UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node includes:

[0363] Determine to hand over the UE to the target logical DU cell based on the correspondence or co-location relationship between the target logical DU cell and the source logical DU cell.

[0364] In some embodiments, the downlink frequency of the target logical DU cell is the same as that of the source logical DU cell, or the downlink frequency of the target logical DU cell is different from that of the source logical DU cell.

[0365] In some embodiments, obtaining relevant information of a target logical DU cell of the mobile IAB node includes:

[0366] The relevant information sent by the source logical DU of the mobile IAB node is obtained through an F1AP message.

[0367] In some embodiments, the relevant information includes one or more of the following information:

[0368] Identification information of the target logical DU cell;

[0369] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0370] Downlink frequency information of the target logical DU cell;

[0371] Measurement reference signal configuration information of the target logical DU cell.

[0372] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0373] receiving a handover command for the UE from a target donor-CU of a target logical DU of the mobile IAB node;

[0374] The handover command is sent to the UE.

[0375] Specifically, the source donor-CU of the source logical DU of the mobile IAB node provided in the embodiment of the present disclosure can implement all the method steps implemented by the method embodiment in which the execution subject is the source donor-CU of the source logical DU of the mobile IAB node, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be described in detail here.

[0376] FIG14 is a schematic diagram of the structure of a mobile IAB node provided in an embodiment of the present disclosure. As shown in FIG14 , the network device includes a memory 1420, a transceiver 1400, and a processor 1410, wherein:

[0377] The memory 1420 is used to store computer programs; the transceiver 1400 is used to send and receive data under the control of the processor 1410; the processor 1410 is used to read the computer program in the memory 1420 and perform the following operations:

[0378] Send relevant information of the target logical DU cell of the mobile IAB node; the relevant information is used to switch the UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node.

[0379] In FIG14 , the bus architecture may include any number of interconnected buses and bridges, specifically various circuits linked together by one or more processors represented by processor 1410 and memory represented by memory 1420. The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface. The transceiver 1400 may be a plurality of components, i.e., a transmitter and a receiver, providing a unit for communicating with various other devices over a transmission medium, such as a wireless channel, a wired channel, an optical cable, or the like. The processor 1410 is responsible for managing the bus architecture and general processing, and the memory 1420 may store data used by the processor 1410 when performing operations.

[0380] The processor 1410 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or a complex programmable logic device (CPLD). The processor may also adopt a multi-core architecture.

[0381] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0382] Determining a beam for the UE to perform RACH-less handover in the target logical DU cell;

[0383] Configure the SSB corresponding to the beam and the CG PUSCH resource for the SSB; the PUSCH resource is used by the UE to send an initial uplink message of RACH-less switching to the target logical DU cell;

[0384] The first configuration information is sent to the target donor-CU of the target logical DU of the mobile IAB node through an F1AP message, wherein the first configuration information is used to indicate the SSB corresponding to the beam and the CG PUSCH resources for the SSB.

[0385] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0386] Determining a beam for the UE to perform RACH-less handover in the target logical DU cell;

[0387] The SSB-related PDCCH corresponding to the beam is used to dynamically schedule the UE to use the authorized PUSCH resources; the PUSCH resources are used by the UE to send an initial uplink message to the target logical DU cell.

[0388] In some embodiments, determining a beam for the UE to perform RACH-less handover in the target logical DU cell includes:

[0389] The beam for the UE to perform RACH-less switching in the target logical DU is determined based on the measurement result of the UE on the target logical DU cell included in the switching preparation information.

[0390] In some embodiments, determining a beam for the UE to perform RACH-less handover in the target logical DU cell includes:

[0391] Determine a beam used by the UE in the source logical DU cell;

[0392] The beam used by the UE for RACH-less handover in the target logical DU cell is determined based on the beam used by the UE in the source logical DU cell.

[0393] In some embodiments, sending relevant information about the target logical DU cell of the mobile IAB node includes:

[0394] The relevant information of the target logical DU cell of the mobile IAB node is sent to the source donor-CU of the source logical DU of the mobile IAB node through an F1AP message.

[0395] In some embodiments, the relevant information includes one or more of the following information:

[0396] Identification information of the target logical DU cell;

[0397] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0398] Downlink frequency information of the target logical DU cell;

[0399] Measurement reference signal configuration information of the target logical DU cell.

[0400] Specifically, the mobile IAB node provided in the embodiment of the present disclosure can implement all the method steps implemented in the method embodiment in which the execution subject is the mobile IAB node, and can achieve the same technical effects. The parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be described in detail here.

[0401] FIG15 is a schematic diagram of the structure of a UE provided in an embodiment of the present disclosure. As shown in FIG15 , the terminal includes a memory 1520, a transceiver 1500, and a processor 1510, wherein:

[0402] The memory 1520 is used to store computer programs; the transceiver 1500 is used to send and receive data under the control of the processor 1510; the processor 1510 is used to read the computer program in the memory 1520 and perform the following operations:

[0403] Determine the PUSCH resources of the SSB corresponding to the beam for RACH-less handover in the target cell;

[0404] An initial uplink message is sent to the target cell using the PUSCH resource.

[0405] In FIG15 , the bus architecture may include any number of interconnected buses and bridges, specifically various circuits connected together by one or more processors represented by processor 1510 and memory represented by memory 1520. The bus architecture may also connect various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and are therefore not described further herein. The bus interface provides an interface. The transceiver 1500 may be a plurality of components, including a transmitter and a receiver, providing a unit for communicating with various other devices over a transmission medium, such as a wireless channel, a wired channel, an optical cable, and the like. For different user devices, the user interface 1530 may also be an interface capable of connecting external or internal devices as required, including but not limited to a keypad, a display, a speaker, a microphone, a joystick, and the like.

[0406] The processor 1510 is responsible for managing the bus architecture and general processing, and the memory 1520 can store data used by the processor 1510 when performing operations.

[0407] In some embodiments, the processor 1510 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or a complex programmable logic device (CPLD). The processor may also adopt a multi-core architecture.

[0408] The processor calls the computer program stored in the memory to execute any of the methods provided by the embodiments of the present disclosure according to the obtained executable instructions. The processor and the memory can also be arranged physically separately.

[0409] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less handover in the target cell includes:

[0410] Receiving a handover command sent by a network device; the handover command includes first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB;

[0411] Based on the first configuration information, the SSB corresponding to the beam for RACH-less switching in the target cell is selected and the PUSCH resources for the SSB are determined.

[0412] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less handover in the target cell includes:

[0413] receiving a handover command sent by a network device; the handover command does not include first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB;

[0414] Determine that the SSB corresponding to the PDCCH used by the target cell to schedule the UE is the SSB corresponding to the beam for performing RACH-less switching in the target cell, detect the PDCCH used by the target cell to schedule the UE; and determine the PUSCH resources scheduled by the PDCCH.

[0415] In some embodiments, the handover command further includes second configuration information, where the second configuration information is used to indicate to the UE an SSB receiving power threshold for selecting SSB;

[0416] The selecting the SSB corresponding to the beam for performing RACH-less switching in the target cell includes:

[0417] Selecting an SSB with a reception power higher than the SSB reception power threshold from among the SSBs indicated in the first configuration information as the SSB corresponding to the beam for RACH-less switching in the target cell; or,

[0418] The SSB whose receiving power corresponding to the PDCCH is higher than the SSB receiving power threshold is selected as the SSB corresponding to the beam for RACH-less switching in the target cell.

[0419] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0420] If the receiving power of the SSB indicated in the first configuration information is lower than the SSB receiving power threshold, or the receiving power threshold of the SSB corresponding to the PDCCH is lower than the SSB receiving power threshold, a random access process is initiated to access the target cell.

[0421] It should be noted here that the above-mentioned terminal provided in the embodiment of the present disclosure can implement all the method steps implemented by the method embodiment in which the execution subject is the terminal, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be described in detail here.

[0422] FIG16 is a schematic diagram of a structure of a switching device provided in an embodiment of the present disclosure. As shown in FIG16 , an embodiment of the present disclosure provides a switching device, including an acquisition module 1601 and a switching module 1602, wherein:

[0423] The acquisition module 1601 is used to obtain relevant information of the target logical DU cell of the mobile IAB node; the switching module 1602 is used to switch the user equipment UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node based on the relevant information.

[0424] In some embodiments, the switching module includes a configuration unit and a first switching unit;

[0425] The configuration unit is used to configure the UE to measure the target logical DU cell;

[0426] The first switching unit is configured to determine, based on the measurement result, a target logical DU cell for switching the UE to the mobile IAB node.

[0427] In some embodiments, the switching module includes a second switching unit;

[0428] The second switching unit is configured to determine, based on a correspondence relationship or a co-location relationship between the target logical DU cell and the source logical DU cell, to switch the UE to the target logical DU cell.

[0429] In some embodiments, the downlink frequency of the target logical DU cell is the same as that of the source logical DU cell, or the downlink frequency of the target logical DU cell is different from that of the source logical DU cell.

[0430] In some embodiments, the acquisition module is specifically configured to:

[0431] The relevant information sent by the source logical DU of the mobile IAB node is obtained through an F1 interface application protocol F1AP message.

[0432] In some embodiments, the relevant information includes one or more of the following information:

[0433] Identification information of the target logical DU cell;

[0434] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0435] Downlink frequency information of the target logical DU cell;

[0436] Measurement reference signal configuration information of the target logical DU cell.

[0437] In some embodiments, the apparatus further comprises a receiving module and a third sending module;

[0438] The receiving module is configured to receive a handover command for the UE from a target donor-CU of a target logical DU of the mobile IAB node;

[0439] The third sending module is configured to send the handover command to the UE.

[0440] Specifically, the switching device provided in the embodiment of the present disclosure can implement all the method steps implemented in the method embodiment in which the execution subject is the source donor-CU of the source logical DU of the mobile IAB node, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be described in detail here.

[0441] FIG17 is a second structural diagram of a switching device provided in an embodiment of the present disclosure. As shown in FIG17 , an embodiment of the present disclosure provides a switching device, including a first sending module 1701, wherein:

[0442] The first sending module 1701 is used to send relevant information of the target logical DU cell of the mobile IAB node; the relevant information is used to switch the UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node.

[0443] In some embodiments, the apparatus further comprises a second determining module, a configuring module, and a fourth sending module;

[0444] The second determining module is configured to determine a beam for the UE to perform RACH-less handover in the target logical DU cell;

[0445] The configuration module is used to configure the synchronization signal block SSB corresponding to the beam and the configuration authorization CG physical uplink shared channel PUSCH resource for the SSB; the PUSCH resource is used by the UE to send the initial uplink message of RACH-less switching to the target logical DU cell;

[0446] The fourth sending module is used to send the first configuration information to the target donor-CU of the target logical DU of the mobile IAB node through an F1AP message, wherein the first configuration information is used to indicate the SSB corresponding to the beam and the CG PUSCH resources for the SSB.

[0447] In some embodiments, the apparatus further comprises a second determination module and a scheduling module;

[0448] The second determining module is configured to determine a beam for the UE to perform RACH-less switching in the target logical DU cell;

[0449] The scheduling module is used to dynamically schedule the UE to use the authorized PUSCH resources using the physical downlink control channel PDCCH related to the SSB corresponding to the beam; the PUSCH resources are used by the UE to send an initial uplink message to the target logical DU cell.

[0450] In some embodiments, the second determining module includes a first determining unit;

[0451] The first determining unit is configured to determine a beam for the UE to perform RACH-less switching in the target logical DU based on a measurement result of the UE on the target logical DU cell included in the switching preparation information.

[0452] In some embodiments, the second determining module includes a second determining unit and a third determining unit;

[0453] The second determining unit is configured to determine a beam used by the UE in the source logical DU cell;

[0454] The third determining unit is configured to determine, based on the beam used by the UE in the source logical DU cell, a beam for the UE to perform RACH-less switching in the target logical DU cell.

[0455] In some embodiments, the first sending module is specifically configured to:

[0456] The relevant information of the target logical DU cell of the mobile IAB node is sent to the source donor-CU of the source logical DU of the mobile IAB node through an F1AP message.

[0457] In some embodiments, the relevant information includes one or more of the following information:

[0458] Identification information of the target logical DU cell;

[0459] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0460] Downlink frequency information of the target logical DU cell;

[0461] Measurement reference signal configuration information of the target logical DU cell.

[0462] Specifically, the switching device provided in the embodiment of the present disclosure can implement all the method steps implemented in the method embodiment in which the execution subject is a mobile IAB node, and can achieve the same technical effects. The parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be described in detail here.

[0463] FIG18 is a third structural diagram of a switching device provided in an embodiment of the present disclosure. As shown in FIG18 , an embodiment of the present disclosure provides a switching device, including a first determining module 1801 and a second sending module 1802, wherein:

[0464] The first determining module 1801 is used to determine the PUSCH resources of the SSB corresponding to the beam for RACH-less switching in the target cell; the second sending module 1802 is used to use the PUSCH resources to send an initial uplink message to the target cell.

[0465] In some embodiments, the first determining module includes a receiving unit and a fourth determining unit;

[0466] The receiving unit is configured to receive a handover command sent by a network device; the handover command includes first configuration information; the first configuration information is configured to indicate an SSB corresponding to the beam for performing RACH-less handover in the target cell and a CG PUSCH resource for the SSB;

[0467] The fourth determination unit is used to select the SSB corresponding to the beam for RACH-less switching in the target cell based on the first configuration information and determine the PUSCH resources for the SSB.

[0468] In some embodiments, the first determining module includes a receiving unit and a fifth determining unit;

[0469] The receiving unit is configured to receive a handover command sent by a network device; the handover command does not include first configuration information; the first configuration information is configured to indicate an SSB corresponding to the beam for performing RACH-less handover in the target cell and a CG PUSCH resource for the SSB;

[0470] The fifth determination unit is used to determine that the SSB corresponding to the PDCCH used by the target cell to schedule the UE is the SSB corresponding to the beam performing RACH-less switching in the target cell, detect the PDCCH used by the target cell to schedule the UE; and determine the PUSCH resources scheduled by the PDCCH.

[0471] In some embodiments, the handover command further includes second configuration information, where the second configuration information is used to instruct the UE to select an SSB receive power threshold for SSB use;

[0472] The fourth determining unit is specifically configured to:

[0473] Selecting an SSB with a reception power higher than the SSB reception power threshold from among the SSBs indicated in the first configuration information as the SSB corresponding to the beam for RACH-less switching in the target cell; or,

[0474] The SSB whose receiving power corresponding to the PDCCH is higher than the SSB receiving power threshold is selected as the SSB corresponding to the beam for RACH-less switching in the target cell.

[0475] In some embodiments, the apparatus further comprises an initiating module;

[0476] The initiating module is used to initiate a random access process to access the target cell if the receiving power of the SSB indicated in the first configuration information is lower than the SSB receiving power threshold, or the receiving power threshold of the SSB corresponding to the PDCCH is lower than the SSB receiving power threshold.

[0477] Specifically, the switching device provided in the embodiment of the present disclosure can implement all the method steps implemented in the method embodiment in which the execution subject is the terminal, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be described in detail here.

[0478] It should be noted that the division of units / modules in the above-mentioned embodiments of the present disclosure is schematic and is merely a logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional units in the various embodiments of the present disclosure may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The above-mentioned integrated units may be implemented in the form of hardware or software functional units.

[0479] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a processor-readable storage medium. Based on this understanding, the technical solution of the present disclosure is essentially or the part that contributes to the relevant technology or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to execute all or part of the steps of the method described in each embodiment of the present disclosure. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0480] In some embodiments, a non-transitory readable storage medium is further provided, wherein the non-transitory readable storage medium stores a computer program, and the computer program is used to enable a processor to execute the switching method provided by the above-mentioned method embodiments.

[0481] Specifically, the above-mentioned non-transitory readable storage medium provided by the embodiment of the present disclosure can implement all the method steps implemented by the above-mentioned method embodiments, and can achieve the same technical effects. The parts and beneficial effects of this embodiment that are the same as the method embodiment will not be described in detail here.

[0482] It should be noted that the non-transitory readable storage medium can be any available medium or data storage device that can be accessed by the processor, including but not limited to magnetic storage (such as floppy disks, hard disks, magnetic tapes, magneto-optical disks (MO), etc.), optical storage (such as CDs, DVDs, BDs, HVDs, etc.), and semiconductor storage (such as ROMs, EPROMs, EEPROMs, non-volatile memories (NAND FLASH), solid-state drives (SSDs)), etc.

[0483] In some embodiments, a processor-readable storage medium is further provided, wherein the processor-readable storage medium stores a computer program, and the computer program is used to enable the processor to execute the switching method provided by the above-mentioned method embodiments.

[0484] Specifically, the processor-readable storage medium provided in the embodiment of the present disclosure can implement all the method steps implemented in the above-mentioned method embodiments and can achieve the same technical effects. The parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be described in detail here.

[0485] In some embodiments, a computer-readable storage medium is further provided, wherein the computer-readable storage medium stores a computer program, and the computer program is used to enable a computer to execute the switching method provided by the above-mentioned method embodiments.

[0486] Specifically, the above-mentioned computer-readable storage medium provided by the embodiment of the present disclosure can implement all the method steps implemented by the above-mentioned method embodiments, and can achieve the same technical effects. The parts and beneficial effects of this embodiment that are the same as the method embodiment will not be described in detail here.

[0487] In some embodiments, a communication device is further provided, in which a computer program is stored, and the computer program is used to enable the communication device to execute the switching method provided by the above-mentioned method embodiments.

[0488] Specifically, the above-mentioned communication device provided by the embodiment of the present disclosure can implement all the method steps implemented by the above-mentioned method embodiments, and can achieve the same technical effects. The parts and beneficial effects of this embodiment that are the same as the method embodiment will not be described in detail here.

[0489] In some embodiments, a chip product is further provided, wherein a computer program is stored in the chip product, and the computer program is used to enable the chip product to execute the switching method provided by the above-mentioned method embodiments.

[0490] Specifically, the above-mentioned chip product provided by the embodiment of the present disclosure can implement all the method steps implemented by the above-mentioned method embodiments, and can achieve the same technical effects. The parts and beneficial effects of this embodiment that are the same as the method embodiment will not be described in detail here.

[0491] It should also be noted that the terms "first," "second," and the like in the embodiments of the present disclosure are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, such that the embodiments of the present disclosure can be implemented in an order other than that illustrated or described herein. Furthermore, the terms "first" and "second" generally distinguish objects of the same type, and do not limit the number of objects. For example, the first object can be one or more.

[0492] In the embodiments of the present disclosure, the term "and / or" describes the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0493] In the embodiments of the present disclosure, "determine B based on A" means that the factor A must be considered when determining B. It is not limited to "B can be determined based on A alone", and should also include: "determine B based on A and C", "determine B based on A, C and E", "determine C based on A, and further determine B based on C", etc. It can also include taking A as a condition for determining B, for example, "when A meets the first condition, use the first method to determine B"; for example, "when A meets the second condition, determine B", etc.; for example, "when A meets the third condition, determine B based on the first parameter", etc. Of course, it can also be a condition that takes A as a factor in determining B, for example, "when A meets the first condition, use the first method to determine C, and further determine B based on C", etc.

[0494] In the embodiments of the present disclosure, the term "plurality" refers to two or more than two, and other quantifiers are similar thereto.

[0495] The technical solution provided by the embodiments of the present disclosure can be applicable to a variety of systems, especially 5G systems. For example, applicable systems may be global system of mobile communication (GSM) systems, code division multiple access (CDMA) systems, wideband code division multiple access (WCDMA) general packet radio service (GPRS) systems, long term evolution (LTE) systems, LTE frequency division duplex (FDD) systems, LTE time division duplex (TDD) systems, long term evolution advanced (LTE-A) systems, universal mobile telecommunication systems (UMTS), worldwide interoperability for microwave access (WiMAX) systems, 5G new air interface (NR) systems, etc. These various systems include terminal devices and network devices. The system may also include a core network part, such as an evolved packet system (EPS), a 5G system (5GS), etc.

[0496] The terminal device involved in the embodiments of the present disclosure may be a device that provides voice and / or data connectivity to a user, a handheld device with wireless connection function, or other processing device connected to a wireless modem. In different systems, the name of the terminal device may also be different. For example, in a 5G system, the terminal device may be called User Equipment (UE). A wireless terminal device can communicate with one or more core networks (CN) via a radio access network (RAN). The wireless terminal device may be a mobile terminal device, such as a mobile phone (or "cellular" phone) and a computer with a mobile terminal device. For example, it may be a portable, pocket-sized, handheld, computer-built-in or vehicle-mounted mobile device that exchanges voice and / or data with a radio access network. For example, Personal Communication Service (PCS) phones, cordless phones, Session Initiated Protocol (SIP) phones, Wireless Local Loop (WLL) stations, Personal Digital Assistants (PDAs), and other devices. The wireless terminal device may also be referred to as a system, a subscriber unit, a subscriber station, a mobile station, a mobile station, a remote station, an access point, a remote terminal device, an access terminal device, a user terminal device, a user agent, or a user device, but is not limited in the embodiments of the present disclosure.

[0497] The network device involved in the embodiments of the present disclosure may be a base station, which may include multiple cells providing services to terminals. Depending on the specific application scenario, the base station may also be called an access point, or may be a device in an access network that communicates with a wireless terminal device through one or more sectors on an air interface, or may be called another name. The network device may be used to interchange received air frames with Internet Protocol (IP) packets, acting as a router between the wireless terminal device and the rest of the access network, wherein the rest of the access network may include an Internet Protocol (IP) communication network. The network device may also coordinate the attribute management of the air interface. For example, the network device involved in the embodiments of the present disclosure may be a base transceiver station (BTS) in the Global System for Mobile communications (GSM) or code division multiple access (CDMA), a network device (NodeB) in wide-band code division multiple access (WCDMA), an evolutionary Node B (eNB or e-NodeB) in the long term evolution (LTE) system, a 5G base station (gNB) in the 5G network architecture (next generation system), a home evolved Node B (HeNB), a relay node, a femto, a pico, etc., and is not limited in the embodiments of the present disclosure. In some network structures, the network device may include a centralized unit (CU) node and a distributed unit (DU) node, and the centralized unit and the distributed unit may also be geographically separated.

[0498] Network devices and terminal devices can each use one or more antennas for Multiple Input Multiple Output (MIMO) transmission. MIMO transmission can be single-user MIMO (SU-MIMO) or multi-user MIMO (MU-MIMO). Depending on the form and number of antenna combinations, MIMO transmission can be 2D-MIMO, 3D-MIMO, FD-MIMO, or massive-MIMO. It can also use diversity transmission, precoding transmission, or beamforming transmission.

[0499] Those skilled in the art will appreciate that the embodiments of the present disclosure may be provided as methods, systems, or computer program products. Therefore, the present disclosure may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present disclosure may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage and optical storage, etc.) containing computer-usable program code.

[0500] The present disclosure is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present disclosure. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer-executable instructions. These computer-executable instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0501] These processor-executable instructions may also be stored in a processor-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the processor-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0502] These processor-executable instructions may also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0503] Obviously, those skilled in the art may make various changes and modifications to the present disclosure without departing from the spirit and scope of the present disclosure. Thus, if these modifications and variations of the present disclosure fall within the scope of the claims of the present disclosure and their equivalents, the present disclosure is intended to include these modifications and variations.

Claims

1. A switching method, characterized in that: The donor-CU of the source logical distribution unit DU applied to the mobile access backhaul integrated IAB node includes: Obtain relevant information of a target logical DU cell of the mobile IAB node; Hand over the user equipment UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node based on the relevant information.

2. The switching method according to claim 1, characterized in that: The switching, based on the relevant information, of the UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node comprises: Configuring the UE to measure the target logical DU cell; Determine a target logical DU cell for handing over the UE to the mobile IAB node based on the measurement result.

3. The switching method according to claim 1, characterized in that: The switching, based on the relevant information, of the UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node comprises: Determine to switch the UE to the target logical DU cell based on the correspondence or co-location relationship between the target logical DU cell and the source logical DU cell.

4. The switching method according to claim 2 or 3, characterized in that: The downlink frequency of the target logical DU cell is the same as that of the source logical DU cell, or the downlink frequency of the target logical DU cell is different from that of the source logical DU cell.

5. The switching method according to any one of claims 1 to 4, characterized in that: The acquiring relevant information of the target logical DU cell of the mobile IAB node includes: The source logic of the mobile IAB node is obtained through the F1 interface application protocol F1AP message The relevant information sent by the editing DU.

6. The switching method according to any one of claims 1 to 4, characterized in that: The relevant information includes one or more of the following information: Identification information of the target logical DU cell; Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell; Downlink frequency information of the target logical DU cell; The measurement reference signal configuration information of the target logical DU cell.

7. The switching method according to any one of claims 1 to 4, characterized in that: The method further comprises: receiving a handover command for the UE from a target donor-CU of a target logical DU of the mobile IAB node; The handover command is sent to the UE.

8. A switching method, characterized in that: Applicable to mobile IAB nodes, including: Send relevant information of the target logical DU cell of the mobile IAB node; the relevant information is used to switch the UE served by the mobile IAB node from the source logical DU cell of the mobile IAB node to the target logical DU cell of the mobile IAB node.

9. The switching method according to claim 8, characterized in that: The method further comprises: Determine a beam for the UE to perform RACH-less handover in the target logical DU cell; Configure the synchronization signal block SSB corresponding to the beam and the configuration authorization CG physical uplink shared channel PUSCH resource for the SSB; the PUSCH resource is used by the UE to send an initial uplink message of RACH-less switching to the target logical DU cell; The first configuration information is sent to the target donor-CU of the target logical DU of the mobile IAB node through an F1AP message, wherein the first configuration information is used to indicate the The SSB corresponding to the beam and the CG PUSCH resources for the SSB.

10. The switching method according to claim 8, characterized in that: The method further comprises: Determine a beam for the UE to perform RACH-less switching in the target logical DU cell; The physical downlink control channel PDCCH associated with the SSB corresponding to the beam is used to dynamically schedule the UE to use the authorized PUSCH resources; the PUSCH resources are used by the UE to send an initial uplink message to the target logical DU cell.

11. The switching method according to claim 9 or 10, characterized in that: Determining a beam for the UE to perform RACH-less switching in the target logical DU cell includes: The beam for the UE to perform RACH-less switching in the target logical DU is determined based on the measurement result of the UE on the target logical DU cell contained in the switching preparation information.

12. The switching method according to claim 9 or 10, characterized in that: Determining a beam for the UE to perform RACH-less switching in the target logical DU cell includes: determining a beam used by the UE in the source logical DU cell; The beam used by the UE for RACH-less switching in the target logical DU cell is determined based on the beam used by the UE in the source logical DU cell.

13. The switching method according to any one of claims 8 to 10, characterized in that: The relevant information of the target logical DU cell of the mobile IAB node is sent, including: The relevant information of the target logical DU cell of the mobile IAB node is sent to the source donor-CU of the source logical DU of the mobile IAB node through an F1AP message.

14. The switching method according to any one of claims 8 to 10, characterized in that: The relevant information includes one or more of the following information: Identification information of the target logical DU cell; The identifier of the source logical DU cell corresponding to or co-located with the target logical DU cell Knowledge information; Downlink frequency information of the target logical DU cell; The measurement reference signal configuration information of the target logical DU cell.

15. A switching method, characterized in that: Applied to UE, including: Determine the PUSCH resources of the SSB corresponding to the beam for RACH-less handover in the target cell; An initial uplink message is sent to the target cell using the PUSCH resource.

16. The switching method according to claim 15, characterized in that: Determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less switching in the target cell includes: Receiving a handover command sent by a network device; the handover command includes first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB; Based on the first configuration information, select the SSB corresponding to the beam for RACH-less switching in the target cell and determine the PUSCH resources for the SSB.

17. The switching method according to claim 15, characterized in that: Determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less switching in the target cell includes: receiving a handover command sent by a network device; the handover command does not include first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB; Determine that the SSB corresponding to the PDCCH of the target cell used to schedule the UE is the SSB corresponding to the beam for performing RACH-less switching in the target cell, detect the PDCCH of the target cell used to schedule the UE; and determine the PUSCH resources scheduled by the PDCCH.

18. The switching method according to claim 16, characterized in that: The handover command further includes second configuration information, where the second configuration information is used to indicate to the UE an SSB receiving power threshold for selecting SSB; The selecting the SSB corresponding to the beam for performing RACH-less switching in the target cell includes: Selecting an SSB with a receiving power higher than the SSB receiving power threshold from among the SSBs indicated in the first configuration information as the SSB corresponding to the beam for performing RACH-less switching in the target cell; or, The SSB whose receiving power corresponding to the PDCCH is higher than the SSB receiving power threshold is selected as the SSB corresponding to the beam for RACH-less switching in the target cell.

19. The switching method according to claim 18, characterized in that: The method further comprises: If the SSB receiving power indicated in the first configuration information is lower than the SSB receiving power threshold, or the SSB receiving power threshold corresponding to the PDCCH is lower than the SSB receiving power threshold, a random access process is initiated to access the target cell.

20. A source donor-CU of a source logical DU of a mobile IAB node, characterized in that: Including memory, transceiver, processor; A memory for storing a computer program; a transceiver for transmitting and receiving data under the control of the processor; and a processor for reading the computer program in the memory and performing the following operations: Obtain relevant information of a target logical DU cell of the mobile IAB node; The UE served by the mobile IAB node is switched from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node based on the relevant information.

21. The source donor-CU of the source logical DU of the mobile IAB node according to claim 20, characterized in that: The switching, based on the relevant information, of the UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node comprises: Configuring the UE to measure the target logical DU cell; Determine a target logical DU cell for handing over the UE to the mobile IAB node based on the measurement result.

22. The source donor-CU of the source logical DU of the mobile IAB node according to claim 20, characterized in that: The switching, based on the relevant information, of the UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node comprises: Determine to switch the UE to the target logical DU cell based on the correspondence or co-location relationship between the target logical DU cell and the source logical DU cell.

23. The source donor-CU of the source logical DU of the mobile IAB node according to claim 21 or 22, characterized in that: The downlink frequency of the target logical DU cell is the same as that of the source logical DU cell, or the downlink frequency of the target logical DU cell is different from that of the source logical DU cell.

24. The source donor-CU of the source logical DU of the mobile IAB node according to any one of claims 20 to 23, characterized in that: The acquiring relevant information of the target logical DU cell of the mobile IAB node includes: The related information sent by the source logical DU of the mobile IAB node is acquired through an F1AP message.

25. The source donor-CU of the source logical DU of the mobile IAB node according to any one of claims 20 to 23, characterized in that: The relevant information includes one or more of the following information: Identification information of the target logical DU cell; Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell; Downlink frequency information of the target logical DU cell; The measurement reference signal configuration information of the target logical DU cell.

26. The source donor-CU of the source logical DU of the mobile IAB node according to any one of claims 20 to 23, characterized in that: The processor is further configured to read the computer program in the memory and perform the following operations: receiving a handover command for the UE from a target donor-CU of a target logical DU of the mobile IAB node; The handover command is sent to the UE.

27. A mobile IAB node, characterized in that: Including memory, transceiver, processor; A memory for storing a computer program; a transceiver for transmitting and receiving data under the control of the processor; and a processor for reading the computer program in the memory and performing the following operations: Send relevant information of the target logical DU cell of the mobile IAB node; The relevant information is used to switch the UE served by the mobile IAB node from a source logical DU cell with the mobile IAB node to a target logical DU cell with the mobile IAB node.

28. The mobile IAB node according to claim 27, characterized in that: The processor is further configured to read the computer program in the memory and perform the following operations: Determine a beam for the UE to perform RACH-less switching in the target logical DU cell; Configure the SSB corresponding to the beam and the CG PUSCH resource for the SSB; the PUSCH resource is used by the UE to send an initial uplink message of RACH-less switching to the target logical DU cell; The first configuration information is sent to the target donor-CU of the target logical DU of the mobile IAB node through an F1AP message, wherein the first configuration information is used to indicate the SSB corresponding to the beam and the CG PUSCH resources for the SSB.

29. The mobile IAB node according to claim 27, characterized in that: The processor is further configured to read the computer program in the memory and perform the following operations: Determine a beam for the UE to perform RACH-less switching in the target logical DU cell; The SSB-related PDCCH corresponding to the beam is used to dynamically schedule the UE to use the authorized PUSCH resources; the PUSCH resources are used by the UE to send an initial uplink message to the target logical DU cell.

30. The mobile IAB node according to claim 28 or 29, characterized in that: Determining a beam for the UE to perform RACH-less switching in the target logical DU cell includes: The beam for the UE to perform RACH-less switching in the target logical DU is determined based on the measurement result of the UE on the target logical DU cell contained in the switching preparation information.

31. The mobile IAB node according to claim 28 or 29, characterized in that: Determining a beam for the UE to perform RACH-less switching in the target logical DU cell includes: Determine a beam used by the UE in the source logical DU cell; The beam used by the UE for RACH-less switching in the target logical DU cell is determined based on the beam used by the UE in the source logical DU cell.

32. The mobile IAB node according to any one of claims 27 to 29, characterized in that: The relevant information of the target logical DU cell of the mobile IAB node is sent, including: The relevant information of the target logical DU cell of the mobile IAB node is sent to the source donor-CU of the source logical DU of the mobile IAB node through an F1AP message.

33. The mobile IAB node according to any one of claims 27 to 29, characterized in that: The relevant information includes one or more of the following information: Identification information of the target logical DU cell; Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell; Downlink frequency information of the target logical DU cell; The measurement reference signal configuration information of the target logical DU cell.

34. A UE, characterized in that: Including memory, transceiver, processor; A memory for storing a computer program; a transceiver for transmitting and receiving data under the control of the processor; and a processor for reading the computer program in the memory and performing the following operations: Determine the PUSCH resources of the SSB corresponding to the beam for RACH-less handover in the target cell; An initial uplink message is sent to the target cell using the PUSCH resource.

35. The UE according to claim 34, characterized in that Determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less switching in the target cell includes: Receiving a handover command sent by a network device; the handover command includes first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB; Based on the first configuration information, select the SSB corresponding to the beam for RACH-less switching in the target cell and determine the PUSCH resources for the SSB.

36. The UE according to claim 34, characterized in that Determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less switching in the target cell includes: receiving a handover command sent by a network device; the handover command does not include first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB; Determine that the SSB corresponding to the PDCCH of the target cell used to schedule the UE is the SSB corresponding to the beam for performing RACH-less switching in the target cell, detect the PDCCH of the target cell used to schedule the UE; and determine the PUSCH resources scheduled by the PDCCH.

37. The UE according to claim 35, characterized in that The handover command further includes second configuration information, where the second configuration information is used to indicate to the UE an SSB receiving power threshold for selecting SSB; The beam selected for RACH-less switching in the target cell corresponds to The SSBs include: Selecting an SSB with a receiving power higher than the SSB receiving power threshold from among the SSBs indicated in the first configuration information as the SSB corresponding to the beam for performing RACH-less switching in the target cell; or, The SSB whose receiving power corresponding to the PDCCH is higher than the SSB receiving power threshold is selected as the SSB corresponding to the beam for RACH-less switching in the target cell.

38. The UE according to claim 37, characterized in that The processor is further configured to read the computer program in the memory and perform the following operations: If the SSB receiving power indicated in the first configuration information is lower than the SSB receiving power threshold, or the SSB receiving power threshold corresponding to the PDCCH is lower than the SSB receiving power threshold, a random access process is initiated to access the target cell.

39. A switching device, characterized in that: include: An acquisition module, used to acquire relevant information of a target logical DU cell of a mobile IAB node; A switching module is used to switch the user equipment UE served by the mobile IAB node from a source logical DU cell of the mobile IAB node to a target logical DU cell of the mobile IAB node based on the relevant information.

40. The switching device according to claim 39, wherein: The switching module includes a configuration unit and a first switching unit; The configuration unit is used to configure the UE to measure the target logical DU cell; The first switching unit is configured to determine, based on the measurement result, a target logical DU cell for switching the UE to the mobile IAB node.

41. The switching device according to claim 39, wherein: The switching module includes a second switching unit; The second switching unit is configured to determine, based on a correspondence relationship or a co-location relationship between the target logical DU cell and the source logical DU cell, whether to switch the UE to the target logical DU cell. Edit DU cell.

42. The switching device according to claim 40 or 41, wherein: The downlink frequency of the target logical DU cell is the same as that of the source logical DU cell, or the downlink frequency of the target logical DU cell is different from that of the source logical DU cell.

43. A switching device according to any one of claims 39 to 42, wherein: The acquisition module is specifically used for: The relevant information sent by the source logical DU of the mobile IAB node is obtained through an F1 interface application protocol F1AP message.

44. A switching device according to any one of claims 39 to 42, wherein: The relevant information includes one or more of the following information: Identification information of the target logical DU cell; Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell; Downlink frequency information of the target logical DU cell; The measurement reference signal configuration information of the target logical DU cell.

45. A switching device according to any one of claims 39 to 42, wherein: The device also includes a receiving module and a third sending module; The receiving module is used to receive a handover command for the UE from a target donor-CU of a target logical DU of the mobile IAB node; The third sending module is used to send the handover command to the UE.

46. ​​A switching device, characterized in that: include: A first sending module, configured to send relevant information of a target logical DU cell of a mobile IAB node; The relevant information is used to switch the UE served by the mobile IAB node from a source logical DU cell with the mobile IAB node to a target logical DU cell with the mobile IAB node.

47. The switching device according to claim 46, wherein: The device also includes a second determining module, a configuration module and a fourth sending module; The second determination module is used to determine the beam for the UE to perform RACH-less switching in the target logical DU cell; The configuration module is used to configure the synchronization signal block SSB corresponding to the beam and the configuration authorization CG physical uplink shared channel PUSCH resource for the SSB; the PUSCH resource is used by the UE to send an initial uplink message of RACH-less switching to the target logical DU cell; The fourth sending module is used to send the first configuration information to the target donor-CU of the target logical DU of the mobile IAB node through an F1AP message, wherein the first configuration information is used to indicate the SSB corresponding to the beam and the CG PUSCH resources for the SSB.

48. The switching device according to claim 46, wherein: The device also includes a second determination module and a scheduling module; The second determination module is used to determine the beam for the UE to perform RACH-less switching in the target logical DU cell; The scheduling module is used to dynamically schedule the UE to use the authorized PUSCH resources using the physical downlink control channel PDCCH associated with the SSB corresponding to the beam; the PUSCH resources are used by the UE to send an initial uplink message to the target logical DU cell.

49. A switching device according to claim 47 or 48, wherein: The second determination module includes a first determination unit; The first determination unit is used to determine the beam for the UE to perform RACH-less switching in the target logical DU based on the measurement result of the UE on the target logical DU cell contained in the switching preparation information.

50. The switching device according to claim 47 or 48, wherein: The second determination module includes a second determination unit and a third determination unit; The second determining unit is used to determine the beam used by the UE in the source logical DU cell; The third determination unit is used to determine the beam for the UE to perform RACH-less switching in the target logical DU cell based on the beam used by the UE in the source logical DU cell.

51. A switching device according to any one of claims 46 to 48, wherein: The first sending module is specifically used for: The relevant information of the target logical DU cell of the mobile IAB node is sent to the source donor-CU of the source logical DU of the mobile IAB node through an F1AP message.

52. A switching device according to any one of claims 46 to 48, wherein: The relevant information includes one or more of the following information: Identification information of the target logical DU cell; Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell; Downlink frequency information of the target logical DU cell; The measurement reference signal configuration information of the target logical DU cell.

53. A switching device, characterized in that: include: The first determination module is used to determine the PUSCH resource of the SSB corresponding to the beam for performing RACH-less switching in the target cell; The second sending module is used to send an initial uplink message to the target cell by using the PUSCH resources.

54. The switching device according to claim 53, wherein: The first determination module includes a receiving unit and a fourth determination unit; The receiving unit is used to receive a handover command sent by a network device; the handover command includes first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB; The fourth determining unit is configured to select, based on the first configuration information, an SSB corresponding to a beam for performing RACH-less switching in the target cell and determine a PUSCH resources.

55. The switching device according to claim 53, wherein: The first determination module includes a receiving unit and a fifth determination unit; The receiving unit is used to receive a handover command sent by a network device; the handover command does not include the first configuration information; the first configuration information is used to indicate the SSB corresponding to the beam for RACH-less handover in the target cell and the CG PUSCH resource for the SSB; The fifth determination unit is used to determine that the SSB corresponding to the PDCCH used by the target cell to schedule the UE is the SSB corresponding to the beam performing RACH-less switching in the target cell, detect the PDCCH used by the target cell to schedule the UE; and determine the PUSCH resources scheduled by the PDCCH.

56. The switching device according to claim 54, wherein: The handover command further includes second configuration information, where the second configuration information is used to indicate to the UE to select an SSB receiving power threshold for use by the SSB; The fourth determining unit is specifically configured to: Selecting an SSB with a receiving power higher than the SSB receiving power threshold from among the SSBs indicated in the first configuration information as the SSB corresponding to the beam for performing RACH-less switching in the target cell; or, The SSB whose receiving power corresponding to the PDCCH is higher than the SSB receiving power threshold is selected as the SSB corresponding to the beam for RACH-less switching in the target cell.

57. The switching device according to claim 56, wherein: The device also includes an initiating module; The initiating module is used to initiate a random access process to access the target cell if the SSB receiving power indicated in the first configuration information is lower than the SSB receiving power threshold, or the SSB receiving power threshold corresponding to the PDCCH is lower than the SSB receiving power threshold.

58. A non-transitory readable storage medium, characterized in that The non-transitory readable storage medium stores a computer program, and the computer program is used to enable a processor to execute the switching method according to any one of claims 1 to 7.

59. A non-transitory readable storage medium, characterized in that: The non-transitory readable storage medium stores a computer program, and the computer program is used to enable a processor to execute the switching method according to any one of claims 8 to 14.

60. A non-transitory readable storage medium, characterized in that The non-transitory readable storage medium stores a computer program, and the computer program is used to enable a processor to execute the switching method according to any one of claims 15 to 19.

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