Switching method and device and storage medium

Abstract

The invention provides a switching method and device and a storage medium. The method comprises the following steps: acquiring related information of a target logic DU cell of a mobile IAB node; and switching user equipment (UE) served by the mobile IAB node from a source logic DU cell co-located with the target logic DU cell to the target logic DU cell based on the related information. According to the switching method and device and the storage medium provided by the invention, the source logic DU of the mobile IAB node reports the related information of the target logic DU cell of the mobile IAB node to the source donor-CU of the source logic DU of the mobile IAB node, so that the source donor-CU of the source logic DU of the mobile IAB node timely acquires the target cell switched by the UE, and the UE is switched between the IAB logic DUs.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a switching method, device and storage medium. Background Art

[0002] Related technologies have begun to discuss the Integrated Access and Backhaul (IAB) nodes to increase support for mobility scenarios, such as installing IAB nodes on vehicles moving at high or low speeds to serve users on the vehicle. Therefore, it is determined that it is necessary to support the change of the donor-CU of the integrated access and backhaul distribution unit (IAB-DU), that is, IAB-DU migration.

[0003] 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 other cells. According to the relevant technology, the source donor-CU can determine the target cell for switching the UE based on the measurement report result of the UE on the neighboring cell. 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 for the UE to switch. Summary of the invention

[0004] The embodiments of the present application provide a switching method, device and storage medium to solve the technical problem in the related art that the source donor-CU cannot determine the target cell for UE switching.

[0005] In a first aspect, an embodiment of the present application provides a switching method, which is applied to a source anchor point centralized unit donor-CU of a source logical distribution unit DU of a mobile access backhaul integrated IAB node, including:

[0006] Obtain relevant information of a target logical DU cell of the mobile IAB node;

[0007] Hand over the user equipment UE served by the mobile IAB node from a source logical DU cell co-located with the target logical DU cell to the target logical DU cell based on the relevant information.

[0008] 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 co-located with the target logical DU cell to the target logical DU cell comprises:

[0009] Configuring the UE to measure the target logical DU cell;

[0010] Determine to switch the UE to the target logical DU cell based on the measurement result.

[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 co-located with the target logical DU cell to the target logical DU cell comprises:

[0012] 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.

[0013] 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.

[0014] In some embodiments, the acquiring relevant information of the target logical DU cell of the mobile IAB node includes:

[0015] The relevant information sent by the source logical DU of the mobile IAB node is obtained through an F1 interface application protocol F1AP message.

[0016] In some embodiments, the relevant information includes one or more of the following information:

[0017] Identification information of the target logical DU cell;

[0018] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0019] Downlink frequency information of the target logical DU cell;

[0020] The measurement reference signal configuration information of the target logical DU cell.

[0021] In some embodiments, the method further comprises:

[0022] receiving a handover command for the UE from a target donor-CU of a target logical DU of the mobile IAB node;

[0023] The handover command is sent to the UE.

[0024] In a second aspect, an embodiment of the present application provides a handover method, which is applied to a mobile IAB node, including:

[0025] 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 co-located with the target logical DU cell to the target logical DU cell.

[0026] In some embodiments, the method further comprises:

[0027] Determine a beam for the UE to perform RACH-less handover in the target logical DU cell;

[0028] 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;

[0029] 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 CGPUSCH resources for the SSB.

[0030] In some embodiments, the method further comprises:

[0031] Determine a beam for the UE to perform RACH-less switching in the target logical DU cell;

[0032] 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.

[0033] In some embodiments, determining a beam for the UE to perform RACH-less switching in the target logical DU cell includes:

[0034] 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.

[0035] In some embodiments, determining a beam for the UE to perform RACH-less switching in the target logical DU cell includes:

[0036] Determine a beam used by the UE in the source logical DU cell;

[0037] 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, determine the beam for the UE to perform RACH-less switching in the target logical DU cell.

[0038] In some embodiments, sending relevant information about a target logical DU cell of the mobile IAB node includes:

[0039] 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.

[0040] In some embodiments, the relevant information includes one or more of the following information:

[0041] Identification information of the target logical DU cell;

[0042] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0043] Downlink frequency information of the target logical DU cell;

[0044] The measurement reference signal configuration information of the target logical DU cell.

[0045] In a third aspect, an embodiment of the present application provides a handover method, applied to a UE, including:

[0046] Determine the PUSCH resources of the SSB corresponding to the beam for RACH-less handover in the target cell;

[0047] An initial uplink message is sent to the target cell using the PUSCH resource.

[0048] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less switching in the target cell includes:

[0049] 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;

[0050] 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.

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

[0052] 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;

[0053] Detecting a PDCCH of the target cell for scheduling the UE;

[0054] The SSB corresponding to the PDCCH is selected as the SSB corresponding to the beam for RACH-less switching in the target cell, and the PUSCH resources scheduled by the PDCCH are determined.

[0055] 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 for use;

[0056] The selecting the SSB corresponding to the beam for performing RACH-less switching in the target cell includes:

[0057] 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,

[0058] 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.

[0059] In some embodiments, the method further comprises:

[0060] 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.

[0061] In a fourth aspect, an embodiment of the present application provides a source donor-CU of a source logical DU of a mobile IAB node, including a memory, a transceiver, and a processor;

[0062] 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:

[0063] Obtain relevant information of a target logical DU cell of the mobile IAB node;

[0064] The UE served by the mobile IAB node is handed over from a source logical DU cell co-located with the target logical DU cell to the target logical DU cell based on the relevant information.

[0065] 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 co-located with the target logical DU cell to the target logical DU cell comprises:

[0066] Configuring the UE to measure the target logical DU cell;

[0067] Determine to switch the UE to the target logical DU cell based on the measurement result.

[0068] 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 co-located with the target logical DU cell to the target logical DU cell comprises:

[0069] 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.

[0070] 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.

[0071] In some embodiments, the acquiring relevant information of the target logical DU cell of the mobile IAB node includes:

[0072] The related information sent by the source logical DU of the mobile IAB node is acquired through an F1AP message.

[0073] In some embodiments, the relevant information includes one or more of the following information:

[0074] Identification information of the target logical DU cell;

[0075] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0076] Downlink frequency information of the target logical DU cell;

[0077] The measurement reference signal configuration information of the target logical DU cell.

[0078] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0079] receiving a handover command for the UE from a target donor-CU of a target logical DU of the mobile IAB node;

[0080] The handover command is sent to the UE.

[0081] In a fifth aspect, an embodiment of the present application provides a mobile IAB node, including a memory, a transceiver, and a processor;

[0082] 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:

[0083] 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 co-located with the target logical DU cell to the target logical DU cell.

[0084] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0085] Determine a beam for the UE to perform RACH-less switching in the target logical DU cell;

[0086] 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;

[0087] 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 CGPUSCH resources for the SSB.

[0088] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0089] Determine a beam for the UE to perform RACH-less switching in the target logical DU cell;

[0090] 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.

[0091] In some embodiments, determining a beam for the UE to perform RACH-less switching in the target logical DU cell includes:

[0092] 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.

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

[0094] Determine a beam used by the UE in the source logical DU cell;

[0095] 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, determine the beam for the UE to perform RACH-less switching in the target logical DU cell.

[0096] In some embodiments, sending relevant information about a target logical DU cell of the mobile IAB node includes:

[0097] 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.

[0098] In some embodiments, the relevant information includes one or more of the following information:

[0099] Identification information of the target logical DU cell;

[0100] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0101] Downlink frequency information of the target logical DU cell;

[0102] The measurement reference signal configuration information of the target logical DU cell.

[0103] In a sixth aspect, an embodiment of the present application provides a UE, including a memory, a transceiver, and a processor;

[0104] 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:

[0105] Determine the PUSCH resources of the SSB corresponding to the beam for RACH-less handover in the target cell;

[0106] An initial uplink message is sent to the target cell using the PUSCH resource.

[0107] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less switching in the target cell includes:

[0108] 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;

[0109] 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.

[0110] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less switching in the target cell includes:

[0111] 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;

[0112] Detecting a PDCCH of the target cell for scheduling the UE;

[0113] The SSB corresponding to the PDCCH is selected as the SSB corresponding to the beam for RACH-less switching in the target cell, and the PUSCH resources scheduled by the PDCCH are determined.

[0114] 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 for use;

[0115] The selecting the SSB corresponding to the beam for performing RACH-less switching in the target cell includes:

[0116] 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,

[0117] 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.

[0118] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0119] 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.

[0120] In a seventh aspect, an embodiment of the present application provides a switching device, including:

[0121] An acquisition module, used to acquire relevant information of a target logical DU cell of a mobile IAB node;

[0122] A switching module is used to switch the user equipment UE served by the mobile IAB node from a source logical DU cell co-located with the target logical DU cell to the target logical DU cell based on the relevant information.

[0123] In some embodiments, the switching module includes a configuration unit and a first switching unit;

[0124] The configuration unit is used to configure the UE to measure the target logical DU cell;

[0125] The first switching unit is configured to determine, based on a measurement result, to switch the UE to the target logical DU cell.

[0126] In some embodiments, the switching module includes a second switching unit;

[0127] The second switching unit is used to determine to switch the UE to the target logical DU cell based on the correspondence relationship or co-location relationship between the target logical DU cell and the source logical DU cell.

[0128] 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.

[0129] In some embodiments, the acquisition module is specifically used to:

[0130] The relevant information sent by the source logical DU of the mobile IAB node is obtained through an F1 interface application protocol F1AP message.

[0131] In some embodiments, the relevant information includes one or more of the following information:

[0132] Identification information of the target logical DU cell;

[0133] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0134] Downlink frequency information of the target logical DU cell;

[0135] The measurement reference signal configuration information of the target logical DU cell.

[0136] In some embodiments, the apparatus further comprises a receiving module and a third sending module;

[0137] 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;

[0138] The third sending module is used to send the handover command to the UE.

[0139] In an eighth aspect, an embodiment of the present application provides a switching device, including:

[0140] The first sending module is used 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 co-located with the target logical DU cell to the target logical DU cell.

[0141] In some embodiments, the apparatus further comprises a second determining module, a configuring module, and a fourth sending module;

[0142] The second determination module is used to determine the beam for the UE to perform RACH-less switching in the target logical DU cell;

[0143] 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;

[0144] The third 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.

[0145] In some embodiments, the apparatus further comprises a second determination module and a scheduling module;

[0146] The second determination module is used to determine the beam for the UE to perform RACH-less switching in the target logical DU cell;

[0147] 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.

[0148] In some embodiments, the second determination module includes a first determination unit;

[0149] 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.

[0150] In some embodiments, the second determination module includes a second determination unit and a third determination unit;

[0151] The second determining unit is used to determine the beam used by the UE in the source logical DU cell;

[0152] The third determination unit is used to determine the beam for UE to perform RACH-less switching in the target logical DU cell 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.

[0153] In some embodiments, the first sending module is specifically used for:

[0154] 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.

[0155] In some embodiments, the relevant information includes one or more of the following information:

[0156] Identification information of the target logical DU cell;

[0157] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0158] Downlink frequency information of the target logical DU cell;

[0159] The measurement reference signal configuration information of the target logical DU cell.

[0160] In a ninth aspect, an embodiment of the present application provides a switching device, including:

[0161] 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;

[0162] The second sending module is used to send an initial uplink message to the target cell by using the PUSCH resources.

[0163] In some embodiments, the first determination module includes a receiving unit and a fourth determination unit;

[0164] 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;

[0165] 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.

[0166] In some embodiments, the first determination module includes a receiving unit, a detection unit, and a fifth determination unit;

[0167] 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;

[0168] The detection unit is used to detect the PDCCH of the target cell for scheduling the UE;

[0169] The fifth determination unit is used to select the SSB corresponding to the PDCCH as the SSB corresponding to the beam for RACH-less switching in the target cell, 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 indicate to the UE an SSB receiving power threshold for selecting SSB for use;

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

[0172] 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,

[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 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.

[0176] In the tenth aspect, an embodiment of the present application 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 a 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 application 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 as described above.

[0178] In the twelfth aspect, an embodiment of the present application 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 as described above.

[0179] In the thirteenth aspect, an embodiment of the present application 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 as described above.

[0180] In a fourteenth aspect, an embodiment of the present application 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 as described above.

[0181] The switching method, device and storage medium provided by the present application enable the source logical DU of the mobile IAB node to report 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 can obtain the target cell of the UE switching in time, thereby realizing the switching of the UE 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 application or the related technologies, the following is a brief introduction to the drawings required for use in the embodiments or the related technical descriptions. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

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

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

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

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

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

[0188] Figure 6 It is a schematic diagram of the routing function of the IAB system;

[0189] Figure 7 It is a schematic diagram of the IAB-DU migration process;

[0190] Figure 8 This is one of the flowcharts of the switching method provided in the embodiment of the present application;

[0191] Fig. 9 This is the second flow chart of the switching method provided in the embodiment of the present application;

[0192] Fig.10 This is the third flow chart of the switching method provided in the embodiment of the present application;

[0193] Fig.11 This is one of the switching principle schematic diagrams provided in the embodiment of the present application;

[0194] Fig.12 This is the second schematic diagram of the switching principle provided in the embodiment of the present application;

[0195] Fig.13 It is a structural diagram of a source donor-CU of a source logical DU of a mobile IAB node provided in an embodiment of the present application;

[0196] Fig.14 is a schematic diagram of the structure of a mobile IAB node provided in an embodiment of the present application;

[0197] Fig.15 It is a structural diagram of a UE provided in an embodiment of the present application;

[0198] Fig.16 It is one of the structural schematic diagrams of the switching device provided in the embodiment of the present application;

[0199] Fig.17 This is the second structural schematic diagram of the switching device provided in the embodiment of the present application;

[0200] Fig.18 This is the third structural schematic diagram of the switching device provided in the embodiment of the present application. DETAILED DESCRIPTION

[0201] The future seamless cellular network deployment requires very flexible and ultra-dense New Radio (NR) cell deployment. Ultra-dense networks are one of the goals of the 5th generation mobile communication (5G). Deploying an NR network without wired backhaul is very important for realizing 5G's ultra-dense network. Since 5G millimeter waves reduce the cell coverage, the wireless self-backhaul system also needs to be multi-hop to meet deployment requirements. 5G's high bandwidth, large-scale multiple input multiple output (MIMO) and beam system make it easier for 5G to develop ultra-dense NR cell wireless self-backhaul systems than Long Term Evolution (LTE). In order to develop this multi-hop system with wireless self-backhaul, 3GPP started the research and standardization of the IAB (Integrated access and backhaul for NR) project in R16. Figure 1 This is a schematic diagram of the IAB system. Figure 1 As shown, access and backhaul adopt NR's Uu air interface wireless transmission, and the relay node supports both access and backhaul functions. The relay node multiplexes the access link (access) and the backhaul link (backhaul) 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 This is a schematic diagram of the IAB network architecture, where: Figure 2 The a in the figure is the IAB architecture of SA mode. Figure 2 b in the figure is the IAB architecture in EN-DC mode. The relay node refers to IAB-node, which supports both access and backhaul functions. The last hop access node on the network side is called IAB-donor, which supports gNB functions and IAB-node access. All UE data can be backhauled to IAB-donor via IAB-node through one or more hops.

[0203] Figure 3 This is a diagram of the Parent IAB-node and Child IAB-node, such as Figure 3 As shown, the functions of IAB-node are divided into two parts, one is the gNB-DU function, called IAB-DU, and the other is the UE function, called IAB-MT. IAB-DU implements the network side equipment function, serves one or more cells and connects to the downstream child IAB-node, provides NR air interface access to UE and downstream child IAB-node, and establishes an F1 connection with IAB donor-CU. IAB-MT implements some terminal equipment functions, connects to the upstream parent IAB-node or IAB-donor DU. IAB-MT includes physical layer, layer 2, RRC and NAS layer functions, and is also indirectly connected to IAB donor-CU and core network. IAB-node can access the network through SA mode or EN-DC mode.

[0204] Figure 4 This is a schematic diagram of the IAB system F1-U protocol stack. Figure 5 This is a schematic diagram of the IAB system F1-C protocol stack, such as Figure 4 and Figure 5 As shown, F1-U and F1-C are built on the transport layer (IP) between IAB-DU and IAB-donor-CU, and the figure goes through two hops of wireless backhaul and one hop of wired backhaul. 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 routing function of the IAB system, and the routing table is provided by the IAB-donor CU. The BAP protocol data unit (PDU) is transmitted in the Radio Link Control (RLC) channel of the backhaul link. Multiple RLC channels of the backhaul link can be configured by the IAB-donor to carry services of different priorities and quality of service (QoS). The BAP entity maps the BAP PDU to different backhaul RLC channels.

[0205] Figure 6 This is a schematic diagram of the routing function of the IAB system. Figure 6As shown in the figure, the routing function of the IAB system is implemented by the BAP layer. Each IAB-node 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 identifier (Routing ID) in the BAP layer data packet header. The Routing ID contains the destination BAP address and the path identifier.

[0206] The routing table contains the mapping relationship between the Routing ID and the next node address. The RLC channel mapping table contains the mapping relationship between the previous hop address, the ingress RLC channel ID, and the next hop address and the egress RLC channel ID. For each data packet, the next hop address can be found from the routing table through the Routing ID in the packet header. The previous hop address and the ingress RLC channel ID are both known. In this way, after the next hop address is determined, the egress RLC channel ID can be found through the RLC channel mapping table based on the previous hop address + ingress RLC channel ID + next hop address.

[0207] NR R18 started the discussion on mobile IAB nodes and added support for mobility scenarios, for example, loading 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 and support 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 the change of the F1 terminated donor-CU, also known as IAB-DU migration.

[0208] Figure 7 This is a schematic diagram of the IAB-DU migration process. Figure 7As shown, when the IAB-DU migrates, 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 still retained between the source logical DU of the IAB node and the source donor-CU. Through two logical DUs and corresponding F1 connections, the UE served by the IAB node can be switched from the source donor-CU and the source logical DU to the target donor-CU and the target logical DU. Subsequently, the source logical DU of the IAB node 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 has the same timing advance (TA) for the two cells, and can support random access channel-less (RACH-less) switching.

[0209] Problem 1: Since the source logical DU needs to release the F1 connection with the source donor-CU after the IAB-DU migration, the UE served by the source logical DU needs to be switched to another cell. According to the relevant technology, the source donor-CU can determine the target cell to switch the UE based on the measurement report result of the UE on the neighboring cell. 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 switch 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 to which the UE is switched.

[0210] Question 2: According to LTE RACH-less handover, the target base station determines to perform RACH-less handover on the UE according to the configuration of Operation Administration and Maintenance (OAM), for example, according to the source and target cell identifiers that allow RACH-less handover configured by OAM. 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 in the handover command of the UE, and the type 1 configured grant (Configured Grant, CG) physical uplink shared channel (PUSCH) resources pre-configured for initial uplink transmission, or the target cell uses the physical downlink control channel (PDCCH) to dynamically schedule the UE's PUSCH transmission. When the UE switches, the random access process is skipped, and the initial uplink message is transmitted in the target cell using the TA configured in the handover command and the pre-configured PUSCH resources or the PUSCH resources dynamically scheduled by the PDCCH. However, unlike LTE RACH-less, in NR RACH-less switching, the UE needs to select a beam to use when switching to the target cell. The related art does not solve the problem of how the UE selects a beam for RACH-less switching.

[0211] Based on the above technical problems, an embodiment of the present application proposes 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 obtains the target cell of the UE switching in time, thereby realizing the switching of the UE between IAB logical DUs.

[0212] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0213] Figure 8 is one of the flow charts of the switching method provided in the embodiment of the present application, such as Figure 8As shown, an embodiment of the present application provides a switching method, the execution subject of which may be a source donor-CU of a source logical DU of a mobile IAB node, etc. 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 application, 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 relevant information is used to hand over the UE served by the mobile IAB node from a source logical DU cell co-located with the target logical DU cell to the target logical DU cell.

[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-DUCONFIGURATION 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] The 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 co-located with the target logical DU cell to the target logical DU cell based on the relevant information.

[0226] Specifically, in an embodiment of the present application, after 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, the UE served by the mobile IAB node is switched from the source logical DU cell co-located with the target logical DU cell to the target logical DU cell 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 co-located with the target logical DU cell to the target logical DU cell comprises:

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

[0229] Determine to switch the UE to the target logical DU cell based on the measurement result.

[0230] Specifically, in an embodiment of the present application, if the downlink frequency of the target logical DU cell and the co-located source logical DU cell are different, the source donor-CU can configure the UE to measure the target logical DU cell according to the measurement reference signal configuration information of the target logical DU cell reported by the IAB node. The source donor-CU determines to switch the UE served by the mobile IAB node to the target logical DU cell based on the measurement result of the UE on the target logical DU cell. It can also be determined to switch 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 co-located with the target logical DU cell to the target logical DU cell comprises:

[0232] 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.

[0233] Specifically, in an embodiment of the present application, if the downlink frequency of the target logical DU cell and the co-located source logical DU cell are the same, since the target logical DU cell and the source logical DU cell cannot work at the same time, the source donor-CU cannot obtain the UE's measurement result of the target logical DU cell. 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.

[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 application, the source donor-CU of the source logical DU of the mobile IAB node receives a handover command for the UE from the target donor-CU of the 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 and the co-located source logical DU cell are the same. If there is an Xn interface between the source donor-CU and the target donor-CU, the source donor-CU can obtain the information of the target logical DU cell 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] In the switching method provided by the present application, 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 obtains the target cell of the UE switching in time, thereby realizing the switching of the UE between IAB logical DUs.

[0242] Fig. 9 This is a second flow chart of the switching method provided in the embodiment of the present application, such as Fig. 9 As shown, the embodiment of the present application provides a switching method, and the execution subject thereof may be a mobile IAB node, etc. The method includes:

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

[0244] Specifically, in the embodiment of the present application, 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 relevant information is used to hand over the UE served by the mobile IAB node from a source logical DU cell co-located with the target logical DU cell to the target logical DU cell.

[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] In the switching method provided by the present application, 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 obtains the target cell of the UE switching in time, thereby realizing the switching 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] 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;

[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 CGPUSCH resources for the SSB.

[0252] Specifically, in an embodiment of the present application, 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 switching 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 RACH-less switching 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, where 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 preconfigures the type 1CG PUSCH resources corresponding to the SSB. The target logical DU of the mobile IAB node generates reconfiguration synchronization (ReconfigurationWithSync) information containing preconfigured 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 preconfigured PUSCH resources. The UE selects the SSB corresponding to the preconfigured PUSCH resources, 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.

[0257] In an embodiment of the present application, the preconfigured PUSCH resources in the switching 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 switching can be achieved.

[0258] In the switching method provided by the present application, 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 obtains the target cell of the UE switching in time, thereby realizing the switching of the UE between IAB logical DUs.

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

[0260] Determine a beam for the UE to perform RACH-less switching 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 an embodiment of the present application, 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 authorized PUSCH resources through PDCCH.

[0263] After the target logical DU of the mobile IAB node determines the beam for the UE to perform RACH-less switching in the target logical DU cell, the 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 the initial uplink message of the RACH-less switching 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 switching, 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 switching command. The UE receives the switching command containing ReconfigurationWithSync. ReconfigurationWithSync does not include pre-configured type1CG 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] In the switching method provided by the present application, 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 obtains the target cell of the UE switching in time, thereby realizing the switching of the UE between IAB logical DUs.

[0266] In some embodiments, the switching command also includes second configuration information, and the second configuration information is used to indicate that the UE selects 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 CGPUSCH 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 an embodiment of the present application, the PUSCH dynamically scheduled by the PDCCH is bound to the SSB, so that the network can obtain 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 switch can be achieved.

[0271] In the switching method provided by the present application, 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 obtains the target cell of the UE switching in time, thereby realizing the switching of the UE between IAB logical DUs.

[0272] In some embodiments, determining a beam for the UE to perform RACH-less switching 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 contained in the switching preparation information.

[0274] Specifically, in an embodiment of the present application, the target logical DU of the mobile IAB node determines 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.

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

[0276] In the switching method provided by the present application, 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 obtains the target cell of the UE switching in time, thereby realizing the switching of the UE between IAB logical DUs.

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

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

[0279] 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, determine the beam for the UE to perform RACH-less switching in the target logical DU cell.

[0280] Specifically, in an embodiment of the present application, 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 switching 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 according to 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] In the switching method provided by the present application, 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 obtains the target cell of the UE switching in time, thereby realizing the switching of the UE between IAB logical DUs.

[0284] Fig.10 This is a third flow chart of the switching method provided in the embodiment of the present application, such as Fig.10As shown, an embodiment of the present application provides a switching method, and the execution subject 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 switching 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 resources for the SSB through a switching command, the UE selects the SSB corresponding to the pre-configured PUSCH resources, 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.

[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 application, 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 switching 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, select the SSB corresponding to the beam for RACH-less switching in the target cell and determine the PUSCH resources for the SSB.

[0293] Specifically, in an embodiment of the present application, 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 switching 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 application, 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 switching 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] Detecting a PDCCH of the target cell for scheduling the UE;

[0300] The SSB corresponding to the PDCCH is selected as the SSB corresponding to the beam for RACH-less switching in the target cell, and the PUSCH resources scheduled by the PDCCH are determined.

[0301] Specifically, in the embodiment of the present application, the target logical DU of the mobile IAB node dynamically schedules the UE to use the authorized PUSCH resources through the PDCCH.

[0302] The UE receives the switching 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 switching 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.

[0303] In the switching method provided by the present application, 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.

[0304] 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 for use;

[0305] The selecting the SSB corresponding to the beam for performing RACH-less switching in the target cell includes:

[0306] 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,

[0307] 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.

[0308] Specifically, in an embodiment of the present application, the switching command also includes second configuration information, and the second configuration information is used to indicate that the UE selects the SSB receiving power threshold used by the SSB.

[0309] 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 SSBs indicated in the first configuration information as the SSB corresponding to the beam for RACH-less switching in the target cell.

[0310] 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.

[0311] In the embodiment of the present application, the UE can select an SSB with better reception quality from multiple pre-configured SSBs or multiple dynamically scheduled SSBs, thereby improving reliability.

[0312] In the switching method provided by the present application, 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.

[0313] In some embodiments, the method further comprises:

[0314] 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 thresholds of SSBs corresponding to all detected PDCCHs are lower than the SSB receiving power threshold, a random access process is initiated to access the target cell.

[0315] Specifically, when the target logical DU of the mobile IAB node is configured with the SSB corresponding to the beam and the CGPUSCH 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 requirement. The UE can fall back to access the target logical DU cell using a random access procedure.

[0316] 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 access the target logical DU cell using the random access process.

[0317] In the embodiment of the present application, the UE can fall back to accessing the target logical DU cell using a random access process when there is no SSB that meets the threshold requirement, thereby ensuring that the handover can be completed and further improving reliability.

[0318] In the switching method provided by the present application, 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.

[0319] The method in the above embodiment is further described below with reference to several specific examples.

[0320] Example 1: When the cells of the source logical DU and the target logical DU of the mobile IAB node use different downlink frequencies, the source donor-CU of the IAB-DU determines 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 UE's measurement result of the target logical DU cell. The target logical DU determines the beam for the UE to perform RACH-less switching based on the UE's measurement result of the target logical DU cell.

[0321] Fig.11 This is one of the switching principle diagrams provided in the embodiment of the present application, such as Fig.11 As shown, the switching process may include the following steps:

[0322] 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.

[0323] 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.

[0324] Step 3: After the target donor-CU allocates resources to the UE, it forwards the handover preparation information (HandoverPreparationInformation) to the target logical DU using the UE CONTEXT SETUPREQUEST 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 SETUPREQUEST message. If the uplink frequencies of the source and target cells meet the condition of belonging to the same timing advance group (TAG), it is determined that the UE can perform RACH-less handover.

[0325] 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 switching preparation information, and pre-configures the type 1CG 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.

[0326] 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 1CG PUSCH resource information corresponding to the SSB pre-configured for UE RACH-less handover.

[0327] 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 REQUESTACKNOWLEDGE) message.

[0328] Step 6: The source donor-CU forwards the handover command to the source logical DU in a UE CONTEXT MODIFICATION message.

[0329] Step 7: The source logical DU sends a handover command (RRCReconfiguration) to the UE. If ReconfigurationWithSync contains a preconfigured type 1CG 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.

[0330] If ReconfigurationWithSync does not include preconfigured type 1CG 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 the received RSRP of the SSB corresponding to the PDCCH meets the threshold requirement, and 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 a random access procedure.

[0331] Example 2: When the source logical DU and target logical DU cells of the mobile IAB node use the same downlink frequency, the source donor-CU of the IAB-DU determines 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. The target logical DU determines the beam for the UE to perform RACH-less switching based on the UE's measurement results of the source logical DU cell.

[0332] Fig.12 This is the second schematic diagram of the switching principle provided in the embodiment of the present application, such as Fig.12 As shown, the switching process may include the following steps:

[0333] 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 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.

[0334] 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.

[0335] Step 3: After the target donor-CU allocates resources to the UE, it forwards the handover preparation information (HandoverPreparationInformation) to the target logical DU using the UE context establishment 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 establishment request message. If the uplink frequencies of the source cell and the target cell meet the condition of belonging to the same TAG, it is determined that the UE can perform RACH-less handover.

[0336] The target logical DU then obtains an equivalent target logical DU cell measurement result based on the source logical DU cell measurement result (measurement result for SSB / CSI-RS) 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 have a quasi-co-location relationship, 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.

[0337] According to the measurement results of the equivalent target logical DU cell, the SSB for the UE to perform RACH-less switching is determined, and the type 1CG PUSCH resources corresponding to the SSB are pre-configured (optionally, also including the RSRP threshold for the UE to select the SSB), or the PDCCH corresponding to the SSB is used to dynamically schedule the UE's PUSCH transmission.

[0338] Step 4: The target logical DU generates a CellGroupConfig information element containing ReconfigurationWithSync and sends it to the target donor-CU through a UE context establishment response message. ReconfigurationWithSync indicates the use of the source cell TA for RACH-less handover and may also include type 1CG PUSCH resource information corresponding to the SSB pre-configured for UE RACH-less handover.

[0339] 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.

[0340] Step 6: The source donor-CU includes the handover command in the UE context modification request message and forwards it to the source logical DU. At the same time, after instructing the source logical DU to send the handover command to the UE, it activates the target logical DU cell and deactivates the source logical DU cell.

[0341] Step 7: The source logical DU sends the handover command to the UE. If ReconfigurationWithSync contains a preconfigured type 1CG 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.

[0342] If ReconfigurationWithSync does not include preconfigured 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 the received RSRP of the SSB corresponding to the PDCCH meets the threshold requirement, and 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 a random access procedure.

[0343] Example 3: When the source logical DU and target logical DU cells of the mobile IAB node use the same downlink frequency, the source donor-CU of the IAB-DU determines 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. The target logical DU determines the beam for the UE to perform RACH-less switching based on the beam used by the UE in the source logical DU cell.

[0344] The switching process may include the following steps:

[0345] 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. 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 is impossible to 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.

[0346] Step 2: The source donor-CU includes the UE's identifier in the source logical DU cell (e.g., Cell Radio Network Temporary Identity (C-RNTI)) or the identifier in the source logical DU (e.g., gNB-DUUE F1AP ID) in the handover request message and sends it to the target donor-CU.

[0347] Step 3: After the target donor-CU allocates resources to the UE, it forwards 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) to the target logical DU using a UE context establishment 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 establishment request message. If the uplink frequencies of the source cell and the target cell meet the condition of belonging to the same TAG, it determines that the UE can perform RACH-less handover.

[0348] 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), and then determines the beam used by the UE in the target logical DU cell based on 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, if SSB#a of the source logical DU cell and SSB#b of the target logical DU cell have a quasi-co-location relationship, if the UE uses SSB#a in the source logical DU cell, it is determined that the UE uses SSB#b in the target logical DU cell. The target logical DU pre-configures the PUSCH resources corresponding to the SSB (optionally, also 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.

[0349] Step 4: The target logical DU generates a CellGroupConfig information element containing ReconfigurationWithSync and sends it to the target donor-CU through a UE context establishment 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 UE RACH-less handover.

[0350] 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.

[0351] Step 6: The source donor-CU includes the handover command in the UE context modification request message and forwards it to the source logical DU. At the same time, after instructing the source logical DU to send the handover command to the UE, it activates the target logical DU cell and deactivates the source logical DU cell.

[0352] Step 7: The source logical DU sends the handover command to the UE. If ReconfigurationWithSync contains pre-configured PUSCH resources, the UE selects the SSB corresponding to the pre-configured PUSCH resources 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. Optionally, the UE selects an SSB in the pre-configured resources whose received RSRP meets the threshold requirement.

[0353] If ReconfigurationWithSync does not include preconfigured 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 the received RSRP of the SSB corresponding to the PDCCH meets the threshold requirement, and the UE selects the SSB corresponding to the PDCCH. If there is no SSB that 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 access the target logical DU cell using a random access procedure.

[0354] Fig.13 is a schematic diagram of the structure of the source donor-CU of the source logical DU of the mobile IAB node provided in an embodiment of the present application, such as Fig.13 As shown, the network device includes a memory 1320, a transceiver 1300, and a processor 1310, wherein:

[0355] 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:

[0356] Obtain relevant information of a target logical DU cell of the mobile IAB node;

[0357] The UE served by the mobile IAB node is handed over from a source logical DU cell co-located with the target logical DU cell to the target logical DU cell based on the relevant information.

[0358] Among them, Fig.13In the embodiment, the bus architecture may include any number of interconnected buses and bridges, specifically one or more processors represented by processor 1310 and various circuits of memory represented by memory 1320 are linked together. The bus architecture may also link together various other circuits such as peripherals, 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 on a transmission medium, which transmission medium may include a wireless channel, a wired channel, an optical cable, and other transmission media. 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.

[0359] 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.

[0360] 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 co-located with the target logical DU cell to the target logical DU cell comprises:

[0361] Configuring the UE to measure the target logical DU cell;

[0362] Determine, based on the measurement result, to switch the UE to the target logical DU cell.

[0363] 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 co-located with the target logical DU cell to the target logical DU cell comprises:

[0364] 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.

[0365] 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.

[0366] In some embodiments, the acquiring relevant information of the target logical DU cell of the mobile IAB node includes:

[0367] The related information sent by the source logical DU of the mobile IAB node is acquired through an F1AP message.

[0368] In some embodiments, the relevant information includes one or more of the following information:

[0369] Identification information of the target logical DU cell;

[0370] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0371] Downlink frequency information of the target logical DU cell;

[0372] The measurement reference signal configuration information of the target logical DU cell.

[0373] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0374] receiving a handover command for the UE from a target donor-CU of a target logical DU of the mobile IAB node;

[0375] The handover command is sent to the UE.

[0376] Specifically, the source donor-CU of the source logical DU of the above-mentioned mobile IAB node provided in the embodiment of the present application can implement all the method steps implemented by the method embodiment in which the above-mentioned 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.

[0377] Fig.14 is a schematic diagram of the structure of a mobile IAB node provided in an embodiment of the present application, such as Fig.14 As shown, the network device includes a memory 1420, a transceiver 1400, and a processor 1410, wherein:

[0378] 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:

[0379] 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 co-located with the target logical DU cell to the target logical DU cell.

[0380] Among them, Fig.14 In the embodiment, the bus architecture may include any number of interconnected buses and bridges, specifically one or more processors represented by processor 1410 and various circuits of memory represented by memory 1420 are linked together. The bus architecture may also link together various other circuits such as peripherals, 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, namely, a transmitter and a receiver, providing a unit for communicating with various other devices on a transmission medium, which transmission medium may include a wireless channel, a wired channel, an optical cable, and other transmission media. 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.

[0381] 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.

[0382] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0383] Determine a beam for the UE to perform RACH-less switching in the target logical DU cell;

[0384] 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;

[0385] 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 CGPUSCH resources for the SSB.

[0386] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0387] Determine a beam for the UE to perform RACH-less switching in the target logical DU cell;

[0388] 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.

[0389] In some embodiments, determining a beam for the UE to perform RACH-less switching in the target logical DU cell includes:

[0390] 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.

[0391] In some embodiments, determining a beam for the UE to perform RACH-less switching in the target logical DU cell includes:

[0392] Determine a beam used by the UE in the source logical DU cell;

[0393] 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, determine the beam for the UE to perform RACH-less switching in the target logical DU cell.

[0394] In some embodiments, sending relevant information about a target logical DU cell of the mobile IAB node includes:

[0395] 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.

[0396] In some embodiments, the relevant information includes one or more of the following information:

[0397] Identification information of the target logical DU cell;

[0398] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0399] Downlink frequency information of the target logical DU cell;

[0400] The measurement reference signal configuration information of the target logical DU cell.

[0401] Specifically, the mobile IAB node provided in the embodiment of the present application can implement all the method steps implemented by the method embodiment in which the execution subject is 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.

[0402] Fig.15 is a schematic diagram of the structure of the UE provided in an embodiment of the present application, such as Fig.15 As shown, the terminal includes a memory 1520, a transceiver 1500, and a processor 1510, wherein:

[0403] 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:

[0404] Determine the PUSCH resources of the SSB corresponding to the beam for RACH-less handover in the target cell;

[0405] An initial uplink message is sent to the target cell using the PUSCH resource.

[0406] Among them, Fig.15 In the embodiment, the bus architecture may include any number of interconnected buses and bridges, specifically one or more processors represented by processor 1510 and various circuits of memory represented by memory 1520 are linked together. The bus architecture may also link together various other circuits such as peripherals, 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 1500 may be a plurality of components, namely, a transmitter and a receiver, providing a unit for communicating with various other devices on a transmission medium, which transmission medium includes a wireless channel, a wired channel, an optical cable, and other transmission media. For different user devices, the user interface 1530 may also be an interface capable of externally and internally connecting required devices, and the connected devices include but are not limited to a keypad, a display, a speaker, a microphone, a joystick, and the like.

[0407] 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.

[0408] 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), and the processor may also adopt a multi-core architecture.

[0409] The processor calls the computer program stored in the memory to execute any of the methods provided in the embodiments of the present application according to the obtained executable instructions. The processor and the memory can also be arranged physically separately.

[0410] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less switching in the target cell includes:

[0411] 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;

[0412] 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.

[0413] In some embodiments, determining a PUSCH resource of an SSB corresponding to a beam for performing RACH-less switching in the target cell includes:

[0414] 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;

[0415] Detecting a PDCCH of the target cell for scheduling the UE;

[0416] The SSB corresponding to the PDCCH is selected as the SSB corresponding to the beam for RACH-less switching in the target cell, and the PUSCH resources scheduled by the PDCCH are determined.

[0417] 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 for use;

[0418] The selecting the SSB corresponding to the beam for performing RACH-less switching in the target cell includes:

[0419] 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,

[0420] 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.

[0421] In some embodiments, the processor is further configured to read the computer program in the memory and perform the following operations:

[0422] 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.

[0423] It should be noted here that the above-mentioned terminal provided in the embodiment of the present application can implement all the method steps implemented by the method embodiment in which the above-mentioned 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 the method embodiment will not be described in detail here.

[0424] Fig.16 is one of the structural diagrams of the switching device provided in the embodiment of the present application, such as Fig.16 As shown, the embodiment of the present application provides a switching device, including an acquisition module 1601 and a switching module 1602, wherein:

[0425] The acquisition module 1601 is used to acquire 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 co-located with the target logical DU cell to the target logical DU cell based on the relevant information.

[0426] In some embodiments, the switching module includes a configuration unit and a first switching unit;

[0427] The configuration unit is used to configure the UE to measure the target logical DU cell;

[0428] The first switching unit is configured to determine, based on a measurement result, to switch the UE to the target logical DU cell.

[0429] In some embodiments, the switching module includes a second switching unit;

[0430] The second switching unit is used to determine to switch the UE to the target logical DU cell based on the correspondence relationship or co-location relationship between the target logical DU cell and the source logical DU cell.

[0431] 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.

[0432] In some embodiments, the acquisition module is specifically used to:

[0433] The relevant information sent by the source logical DU of the mobile IAB node is obtained through an F1 interface application protocol F1AP message.

[0434] In some embodiments, the relevant information includes one or more of the following information:

[0435] Identification information of the target logical DU cell;

[0436] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0437] Downlink frequency information of the target logical DU cell;

[0438] The measurement reference signal configuration information of the target logical DU cell.

[0439] In some embodiments, the apparatus further comprises a receiving module and a third sending module;

[0440] 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;

[0441] The third sending module is used to send the handover command to the UE.

[0442] Specifically, the above-mentioned switching device provided in the embodiment of the present application 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 the method embodiment will not be described in detail here.

[0443] Fig.17This is a second structural diagram of the switching device provided in the embodiment of the present application, such as Fig.17 As shown, the embodiment of the present application provides a switching device, including a first sending module 1701, wherein:

[0444] 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 co-located with the target logical DU cell to the target logical DU cell.

[0445] In some embodiments, the apparatus further comprises a second determining module, a configuring module, and a fourth sending module;

[0446] The second determination module is used to determine the beam for the UE to perform RACH-less switching in the target logical DU cell;

[0447] 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;

[0448] The third 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.

[0449] In some embodiments, the apparatus further comprises a second determination module and a scheduling module;

[0450] The second determination module is used to determine the beam for the UE to perform RACH-less switching in the target logical DU cell;

[0451] 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.

[0452] In some embodiments, the second determination module includes a first determination unit;

[0453] 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.

[0454] In some embodiments, the second determination module includes a second determination unit and a third determination unit;

[0455] The second determining unit is used to determine the beam used by the UE in the source logical DU cell;

[0456] The third determination unit is used to determine the beam for RACH-less switching of the UE in the target logical DU cell 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.

[0457] In some embodiments, the first sending module is specifically used for:

[0458] 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.

[0459] In some embodiments, the relevant information includes one or more of the following information:

[0460] Identification information of the target logical DU cell;

[0461] Identification information of the source logical DU cell corresponding to or co-located with the target logical DU cell;

[0462] Downlink frequency information of the target logical DU cell;

[0463] The measurement reference signal configuration information of the target logical DU cell.

[0464] Specifically, the switching device provided in the embodiment of the present application can implement all the method steps implemented by the method embodiment in which the execution subject is a 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.

[0465] Fig.18 This is the third structural diagram of the switching device provided in the embodiment of the present application, such as Fig.18 As shown, the embodiment of the present application provides a switching device, including a first determining module 1801 and a second sending module 1802, wherein:

[0466] The first determination 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.

[0467] In some embodiments, the first determination module includes a receiving unit and a fourth determination unit;

[0468] 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;

[0469] 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.

[0470] In some embodiments, the first determination module includes a receiving unit, a detection unit, and a fifth determination unit;

[0471] 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;

[0472] The detection unit is used to detect the PDCCH of the target cell for scheduling the UE;

[0473] The fifth determination unit is used to select the SSB corresponding to the PDCCH as the SSB corresponding to the beam for RACH-less switching in the target cell, and determine the PUSCH resources scheduled by the PDCCH.

[0474] 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 for use;

[0475] The fourth determining unit is specifically configured to:

[0476] 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,

[0477] 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.

[0478] In some embodiments, the apparatus further comprises an initiating module;

[0479] 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.

[0480] Specifically, the above-mentioned switching device provided in the embodiment of the present application 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 the method embodiment will not be described in detail here.

[0481] It should be noted that the division of units / modules in the above embodiments of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation. In addition, the functional units in the various embodiments of the present application may be integrated into a processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated units may be implemented in the form of hardware or in the form of software functional units.

[0482] 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 application 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 to enable a computer device (which can be a personal computer, server, or network device, etc.) or a processor (processor) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), disk or optical disk and other media that can store program codes.

[0483] 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.

[0484] Specifically, the above-mentioned non-transitory readable storage medium provided in the embodiment of the present application 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 that are the same as the method embodiments in this embodiment will not be described in detail here.

[0485] 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 CD, DVD, BD, HVD, etc.), and semiconductor storage (such as ROM, EPROM, EEPROM, non-volatile memory (NAND FLASH), solid-state drive (SSD)), etc.

[0486] 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 a processor to execute the switching method provided by the above-mentioned method embodiments.

[0487] Specifically, the processor-readable storage medium provided in the embodiment of the present application 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 that are the same as those in the method embodiments will not be described in detail herein.

[0488] 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.

[0489] Specifically, the above-mentioned computer-readable storage medium provided in the embodiment of the present application can implement all the method steps implemented by the above-mentioned method embodiments, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as the method embodiment will not be described in detail here.

[0490] In some embodiments, a communication device is further provided, wherein a computer program is stored in the communication device, and the computer program is used to enable the communication device to execute the switching method provided by the above-mentioned method embodiments.

[0491] Specifically, the above-mentioned communication device provided in the embodiment of the present application 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 that are the same as the method embodiments in this embodiment will not be described in detail here.

[0492] 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.

[0493] Specifically, the above-mentioned chip product provided in the embodiment of the present application 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.

[0494] It should also be noted that the terms "first", "second", etc. in the embodiments of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first" and "second" are generally of the same type, and the number of objects is not limited. For example, the first object can be one or more.

[0495] In the embodiments of the present application, the term "and / or" describes the association relationship of the associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0496] "Determine B based on A" in the embodiments of the present application means that the factor A should be considered when determining B. It is not limited to "B can be determined based on A alone", but 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. In addition, 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 another example, "When A meets the second condition, determine B", etc.; for another 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 for 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.

[0497] In the embodiments of the present application, the term "plurality" refers to two or more than two, and other quantifiers are similar.

[0498] The technical solution provided in the embodiment of the present application can be applicable to a variety of systems, especially 5G systems. For example, the applicable system can be a global system of mobile communication (GSM) system, a code division multiple access (CDMA) system, a wideband code division multiple access (WCDMA) general packet radio service (GPRS) system, a long term evolution (LTE) system, a LTE frequency division duplex (FDD) system, a LTE time division duplex (TDD) system, an advanced long term evolution (LTE-A) system, a universal mobile telecommunication system (UMTS), a world-wide interoperability for microwave access (WiMAX) system, a 5G new radio (NR) system, etc. These various systems include terminal equipment and network equipment. The system may also include a core network part, such as an evolved packet system (EPS), a 5G system (5GS), etc.

[0499] The terminal device involved in the embodiment of the present application may be a device that provides voice and / or data connectivity to a user, a handheld device with a wireless connection function, or other processing devices 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 a 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 a "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 language and / or data with a wireless access network. For example, personal communication service (PCS) phones, cordless phones, session initiation 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, and a user device, but is not limited in the embodiments of the present application.

[0500] The network device involved in the embodiment of the present application may be a base station, which may include multiple cells providing services for the terminal. Depending on the specific application scenario, the base station may also be called an access point, or may be a device in the access network that communicates with the wireless terminal device through one or more sectors on the air interface, or other names. The network device may be used to interchange received air frames with Internet Protocol (IP) packets, and serve 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 application may be a network device (Base Transceiver Station, BTS) in the Global System for Mobile communications (Global System for Mobile communications, GSM) or Code Division Multiple Access (Code Division Multiple Access, CDMA), or a network device (NodeB) in Wide-band Code Division Multiple Access (WCDMA), or an evolutionary network device (evolutional Node B, eNB or e-NodeB) in the long term evolution (long term evolution, LTE) system, a 5G base station (gNB) in the 5G network architecture (next generation system), or a home evolved Node B (Home evolved Node B, HeNB), a relay node, a home base station (femto), a pico base station (pico), etc., which is not limited in the embodiments of the present application. 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 arranged geographically separately.

[0501] Network devices and terminal devices can each use one or more antennas for multi-input multi-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, or it can be diversity transmission, precoding transmission or beamforming transmission, etc.

[0502] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) that contain computer-usable program code.

[0503] The present application 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 application. 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 generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0504] 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 work in a specific manner, so that the instructions stored in the processor readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0505] 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, thereby providing instructions for executing on the computer or other programmable device to implement the process. Figure 1A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0506] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also 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 a source logical DU cell co-located with the target logical DU cell to the target logical DU cell 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 co-located with the target logical DU cell to the target logical DU cell comprises: Configuring the UE to measure the target logical DU cell; Determine to switch the UE to the target logical DU cell 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 co-located with the target logical DU cell to the target logical DU cell 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 relevant information sent by the source logical DU of the mobile IAB node is obtained through an F1 interface application protocol F1AP message.

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 a source logical DU cell co-located with the target logical DU cell to the target logical DU cell.

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 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: Determine a beam used by the UE in the source logical DU cell; 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, determine the beam for the UE to perform RACH-less switching in the target 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; 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.

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 CGPUSCH 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 CGPUSCH resource for the SSB; Detecting a PDCCH of the target cell for scheduling the UE; The SSB corresponding to the PDCCH is selected as the SSB corresponding to the beam for RACH-less switching in the target cell, and the PUSCH resources scheduled by the PDCCH are determined.

18. The switching method according to claim 17, 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 handed over from a source logical DU cell co-located with the target logical DU cell to the target logical DU cell 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 co-located with the target logical DU cell to the target logical DU cell comprises: Configuring the UE to measure the target logical DU cell; Determine to switch the UE to the target logical DU cell 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 co-located with the target logical DU cell to the target logical DU cell 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 co-located with the target logical DU cell to the target logical DU cell.

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; 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, determine the beam for the UE to perform RACH-less switching in the target 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 CGPUSCH 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 CGPUSCH resource for the SSB; Detecting a PDCCH of the target cell for scheduling the UE; The SSB corresponding to the PDCCH is selected as the SSB corresponding to the beam for RACH-less switching in the target cell, and the PUSCH resources scheduled by the PDCCH are determined.

37. The UE according to claim 36, 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.

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 co-located with the target logical DU cell to the target logical DU cell based on the relevant information.

40. 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 co-located with the target logical DU cell to the target logical DU cell.

41. 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.

42. 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.

43. 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.

44. 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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