Cell handover processing method and apparatus, and device and storage medium

Abstract

The present application belongs to the technical field of communications. Disclosed are a cell handover processing method and apparatus, and a device and a storage medium. The cell handover processing method in the embodiments of the present application comprises: a terminal acquiring at least one LTM candidate cell configuration; and when the terminal is handed over to a target cell, the terminal releasing or retaining at least some LTM candidate cell configurations among at least one LTM candidate cell configuration according to a first rule, wherein the first rule comprises at least one of the following: whether the target cell meets a first condition; and indication information, which is sent by the target cell.

Description

Cell handover processing method, device, equipment and storage medium

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application number 202311157418.9 filed on September 7, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application belongs to the field of communication technology, and specifically relates to a method, device, equipment and storage medium for processing cell switching. Background Art

[0004] The network can pre-configure conditional handover (CHO) configurations for the terminal, which then evaluates whether the execution conditions are met to perform a cell handover. For CHO, such as conditional Layer 1 or Layer 2-triggered mobility (LTM) handovers, existing protocols only support continuous LTM handovers within a centralized unit (CU), known as intra-CU.

[0005] In the mobility enhancement project, LTM between CUs (called Inter-CU) is supported. Inter-CU LTM switching involves changes to the Packet Data Convergence Protocol (PDCP) entity on the network side, so a cell key change is required. After the cell key change, the other candidate cell keys prepared by the source CU can no longer be used. Therefore, when the terminal continues to perform LTM switching, the terminal cannot apply the configuration of these candidate cells to switch to the corresponding candidate cell, resulting in the failure of the terminal's radio link.

[0006] Summary of the Invention

[0007] The embodiments of the present application provide a cell switching processing method, apparatus, device and storage medium, which can solve the problem that when an Inter-CU switching occurs, the terminal continues to perform LTM switching, resulting in the failure of the terminal's wireless link.

[0008] In a first aspect, a method for processing cell switching is provided, the method comprising: a terminal acquiring at least one LTM candidate cell configuration; when the terminal switches to a target cell, the terminal releases or retains at least part of the at least one LTM candidate cell configuration according to a first rule; wherein the first rule comprises any one of the following: whether the target cell satisfies a first condition; indication information sent by the target cell.

[0009] In a second aspect, a method for processing cell switching is provided, which includes: when the target CU confirms that the terminal has switched to the target cell, sending indication information to the terminal; wherein the indication information is used to release or retain at least part of the LTM candidate cell configuration in at least one LTM candidate cell configuration.

[0010] In a third aspect, a method for processing a cell handover is provided, the method comprising: a source CU sending first information to a first CU, the first CU being all candidate CUs or a target CU, the first information being used by the target CU to send indication information to a terminal, the indication information being used to release or retain at least some of the at least one LTM candidate cell configuration; wherein the first information includes at least one of the following:

[0011] Configuration identifier of each LTM candidate cell;

[0012] The PCI and frequency associated with the configuration identifier of each LTM candidate cell;

[0013] The CGI associated with the configuration identifier of each LTM candidate cell;

[0014] The first identifier associated with each LTM candidate cell;

[0015] The identifier of the first list to which each LTM candidate cell belongs.

[0016] In the fourth aspect, a method for processing cell switching is provided, which includes: when the target CU confirms that the terminal switches to the target cell, the target CU sends a second message to the target DU; wherein the second information includes at least one of the following: a second indication information, used to indicate to stop sending the LTM switching command to the terminal; a list of identifications of candidate target cells.

[0017] In a fifth aspect, a cell handover processing device is provided, comprising: an acquisition module and a processing module. The acquisition module is configured to acquire at least one LTM candidate cell configuration. The processing module is configured to release or retain at least some of the at least one LTM candidate cell configurations according to a first rule when handing over to a target cell. The first rule includes any one of the following: whether the target cell satisfies a first condition; or indication information sent by the target cell.

[0018] In a sixth aspect, a cell handover processing device is provided, the device comprising: a sending module. The sending module is configured to send indication information to a terminal upon confirming that the terminal has been handed over to a target cell; wherein the indication information is configured to release or retain at least part of at least one LTM candidate cell configuration.

[0019] In a seventh aspect, a cell handover processing device is provided, the device comprising: a sending module. The sending module is configured to send first information to a first CU, where the first CU is any candidate CU or a target CU, the first information being used by the target CU to send indication information to a terminal, the indication information being used to release or retain at least some of at least one LTM candidate cell configuration; wherein the first information includes at least one of the following:

[0020] Configuration identifier of each LTM candidate cell;

[0021] The PCI and frequency associated with the configuration identifier of each LTM candidate cell;

[0022] The CGI associated with the configuration identifier of each LTM candidate cell;

[0023] The first identifier associated with each LTM candidate cell;

[0024] The identifier of the first list to which each LTM candidate cell belongs.

[0025] In an eighth aspect, a cell handover processing device is provided, comprising: a sending module. The sending module is configured to send second information to a target DU upon confirming that a terminal has been handed over to a target cell; wherein the second information includes at least one of the following: second indication information for instructing to stop sending an LTM handover command to the terminal; and a list of identifiers of candidate target cells.

[0026] In a ninth aspect, a terminal is provided, comprising a processor and a memory, wherein the memory stores programs or instructions that can be run on the processor, and when the programs or instructions are executed by the processor, the steps of the method described in the first aspect are implemented.

[0027] In a tenth aspect, a terminal is provided, comprising a processor and a communication interface, wherein the communication interface is configured to obtain at least one LTM candidate cell configuration. The processor is configured to release or retain at least some of the at least one LTM candidate cell configurations according to a first rule when switching to a target cell; wherein the first rule includes any one of the following: whether the target cell satisfies a first condition; or indication information sent by the target cell.

[0028] In the eleventh aspect, a network side device is provided, which includes a processor and a memory, wherein the memory stores programs or instructions that can be run on the processor, and when the program or instructions are executed by the processor, the steps of the method described in the second aspect are implemented, or the steps of the method described in the third aspect are implemented, or the steps of the method described in the fourth aspect are implemented.

[0029] In the twelfth aspect, a network side device is provided, including a processor and a communication interface, wherein the communication interface is used to send indication information to the terminal when confirming that the terminal has switched to the target cell; wherein the indication information is used to release or retain at least part of the LTM candidate cell configuration in at least one LTM candidate cell configuration.

[0030] Alternatively, the communication interface is used to send first information to a first CU, where the first CU is all candidate CUs or target CUs, and the first information is used for the target CU to send indication information to the terminal, where the indication information is used to release or retain at least part of the LTM candidate cell configuration in at least one LTM candidate cell configuration; wherein the first information includes at least one of the following:

[0031] Configuration identifier of each LTM candidate cell;

[0032] The PCI and frequency associated with the configuration identifier of each LTM candidate cell;

[0033] The CGI associated with the configuration identifier of each LTM candidate cell;

[0034] The first identifier associated with each LTM candidate cell;

[0035] The identifier of the first list to which each LTM candidate cell belongs.

[0036] Alternatively, the communication interface is used to send second information to the target DU when confirming that the terminal switches to the target cell; wherein the second information includes at least one of the following: second indication information, used to indicate to stop sending the LTM switching command to the terminal; a list of identifiers of candidate target cells.

[0037] In the thirteenth aspect, a readable storage medium is provided, on which a program or instruction is stored. When the program or instruction is executed by a processor, the steps of the method described in the first aspect are implemented, or the steps of the method described in the second aspect are implemented, or the steps of the method described in the third aspect are implemented, or the steps of the method described in the fourth aspect are implemented.

[0038] In the fourteenth aspect, a wireless communication system is provided, including: a terminal and a network side device, wherein the terminal can be used to execute the steps of the method described in the first aspect, the network side device can be used to execute the steps of the method described in the second aspect, or the network side device can be used to execute the steps of the method described in the third aspect.

[0039] In the fifteenth aspect, a chip is provided, comprising a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the method described in the first aspect, or the method described in the second aspect, or the method described in the third aspect, or the method described in the fourth aspect.

[0040] In the sixteenth aspect, a computer program / program product is provided, which is stored in a storage medium, and the program / program product is executed by at least one processor to implement the steps of the cell switching processing method as described in the first aspect, or the steps of the cell switching processing method as described in the second aspect, or the steps of the cell switching processing method as described in the third aspect, or the steps of the cell switching processing method as described in the fourth aspect.

[0041] In an embodiment of the present application, after switching to the target cell, the terminal can release or retain at least part of the LTM candidate cell configuration according to a first rule, and the first rule includes whether the target cell meets the first condition, or includes indication information sent by the target cell. In this solution, the terminal can determine whether the switch is an Inter-CU switch by judging whether the target cell meets the first condition, and decide the LTM candidate cell configuration that needs to be released or retained according to the judgment result; or the terminal can decide the LTM candidate cell configuration that needs to be released or retained according to the indication information sent by the target cell, and the indication information is sent to the terminal after the target CU determines whether the switch is an Inter-CU switch. In this way, after the Inter-CU switch occurs, the terminal can decide independently or according to the indication of the indication information to release or retain at least part of the LTM candidate cell configuration, which can avoid subsequent switching to an unavailable LTM candidate cell, thereby avoiding the failure of the terminal's wireless link and improving the accuracy of cell switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] FIG1 is a schematic diagram of the architecture of a wireless communication system provided in an embodiment of the present application;

[0043] FIG2 is a schematic diagram of a CU-DU architecture provided by the related art;

[0044] FIG3A is one of the schematic diagrams for CU and DU switching provided by the related art;

[0045] FIG3B is a second schematic diagram of a CU and DU switching method provided by the related art;

[0046] FIG3C is a third schematic diagram of a CU and DU switching method provided by the related art;

[0047] FIG4 is a flowchart of a method for processing a cell handover according to an embodiment of the present application;

[0048] FIG5 is a second flowchart of a method for processing a cell handover according to an embodiment of the present application;

[0049] FIG6 is a third flowchart of a method for processing a cell handover according to an embodiment of the present application;

[0050] FIG7 is a fourth flowchart of a method for processing a cell handover according to an embodiment of the present application;

[0051] FIG8 is a schematic diagram of a structure of a cell handover processing device according to an embodiment of the present application;

[0052] FIG9 is a second structural diagram of a cell handover processing device provided in an embodiment of the present application;

[0053] FIG10 is a third structural diagram of a cell handover processing device provided in an embodiment of the present application;

[0054] FIG11 is a fourth structural diagram of a cell handover processing device provided in an embodiment of the present application;

[0055] FIG12 is a fifth structural diagram of a cell handover processing device provided in an embodiment of the present application;

[0056] FIG13 is a sixth structural diagram of a cell handover processing device provided in an embodiment of the present application;

[0057] FIG14 is a schematic diagram of the hardware structure of a communication device provided in an embodiment of the present application;

[0058] FIG15 is a schematic diagram of the hardware structure of a terminal provided in an embodiment of the present application;

[0059] FIG16 is a schematic diagram of the hardware structure of a network-side device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0060] The following will be combined with the accompanying drawings in the embodiments of this application to clearly describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of this application.

[0061] The terms "first", "second", etc. in this 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 are interchangeable where appropriate, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first" and "second" are generally of the same type, and do not limit the number of objects, for example, the first object can be one or more. In addition, "or" in this application represents at least one of the connected objects. For example, "A or B" covers three options, namely, Option 1: including A but not including B; Option 2: including B but not including A; Option 3: including both A and B. The character " / " generally indicates that the objects associated before and after are in an "or" relationship.

[0062] The term "indication" in this application can be either a direct indication (or explicit indication) or an indirect indication (or implicit indication). A direct indication can be understood as the sender explicitly informing the receiver of specific information, the operation to be performed, or the requested result, etc. in the instruction sent; an indirect indication can be understood as the receiver determining the corresponding information based on the instruction sent by the sender, or making a judgment and determining the operation to be performed or the requested result, etc. based on the judgment result.

[0063] The terms "at least one" and "at least one of" in this application refer to any one, any two, or a combination of more than two of the objects included. For example, at least one of a, b, and c can be represented by: "a", "b", "c", "a and b", "a and c", "b and c", and "a, b, and c", where a, b, and c can be single or multiple. Similarly, "at least two" means two or more, and its meaning is similar to "at least one".

[0064] It is worth noting that the technology described in the embodiments of the present application is not limited to the Long Term Evolution (LTE) / LTE-Advanced (LTE-A) system, but can also be used in other wireless communication systems, such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single-carrier Frequency-Division Multiple Access (SC-FDMA) or other systems. The terms "system" and "network" in the embodiments of the present application are often used interchangeably, and the technology described can be used for the systems and radio technologies mentioned above, as well as for other systems and radio technologies. The following description describes a New Radio (NR) system for illustrative purposes, and NR terminology is used in most of the following description, but these technologies can also be applied to systems other than NR systems, such as 6th generation (6G) systems. th Generation, 6G) communication system.

[0065] FIG1 is a block diagram of a wireless communication system applicable to an embodiment of the present application. The wireless communication system includes a terminal 11 and a network-side device 12. The terminal 11 may be a mobile phone, a tablet computer (Tablet Personal Computer), a laptop computer (Laptop Computer), a notebook computer, a personal digital assistant (PDA), a handheld computer, a netbook, an ultra-mobile personal computer (UMPC), a mobile internet device (MID), an augmented reality (AR), a virtual reality (VR) device, a robot, a wearable device (Wearable Device), an aircraft (Flight Vehicle), a vehicle-mounted device (VUE), a ship-mounted device, a pedestrian user equipment (PUE), a smart home (home appliances with wireless communication capabilities, such as refrigerators, televisions, washing machines, or furniture), a game console, a personal computer (PC), an ATM, or a self-service machine, or other terminal-side devices. Wearable devices include: smart watches, smart bracelets, smart headphones, smart glasses, smart jewelry (smart bracelets, smart bracelets, smart rings, smart necklaces, smart anklets, smart anklets, etc.), smart wristbands, smart clothing, etc. Among them, the vehicle-mounted device can also be called a vehicle-mounted terminal, a vehicle-mounted controller, a vehicle-mounted module, a vehicle-mounted component, a vehicle-mounted chip or a vehicle-mounted unit, etc. It should be noted that the specific type of the terminal 11 is not limited in the embodiment of the present application. The network side device 12 may include an access network device or a core network device, wherein the access network device may also be called a radio access network (Radio Access Network, RAN) device, a radio access network function or a radio access network unit. The access network device may include a base station, a wireless local area network (WLAN) access point (AS) or a wireless fidelity (WiFi) node, etc.Among them, the base station can be referred to as Node B (NB), Evolved Node B (eNB), the next generation Node B (gNB), New Radio Node B (NR Node B), access point, Relay Base Station (RBS), Serving Base Station (SBS), Base Transceiver Station (BTS), radio base station, radio transceiver, Basic Service Set (BSS), Extended Service Set (ESS), Home Node B (HNB), Home evolved Node B (home evolved Node B), Transmission Reception Point (TRP) or other appropriate terms in the relevant field. As long as the same technical effect is achieved, the base station is not limited to specific technical vocabulary. It should be noted that in the embodiment of the present application, only the base station in the NR system is used as an example for introduction, and the specific type of the base station is not limited.

[0066] The following explains some concepts and / or terms involved in a cell switching processing method, apparatus, device and storage medium provided in an embodiment of the present application.

[0067] 1. CU-Distributed Unit (DU) Architecture

[0068] The NR access network splits the gNB into the gNB-CU and gNB-DU, which are connected via the F1 interface. The CU-DU architecture is shown in Figure 2.

[0069] Among them, a gNB contains only one CU, one or more DUs, and one DU contains one or more cells.

[0070] The CU includes the protocol stacks of PDCP and above, and the DU includes the protocol stacks below the PDCP layer, such as Radio Link Control (RLC), Medium Access Control (MAC), and Physical (PHY).

[0071] On the control plane, the CU includes Radio Resource Control (RRC) and the PDCP (PDCP-C) of the control plane;

[0072] On the user plane, the CU includes the Service Data Adaptation Protocol (SDAP) and the PDCP of the user plane (PDCP-U).

[0073] (1) Intra-CU, Intra-DU switching

[0074] The terminal switches between different cells within the same DU under the same CU. As shown in Figure 3A, when the terminal switches from cell 1 of DU1 to cell 2 of DU1, the PDCP and RLC entities on the terminal side are not affected because the physical locations of the entities at each layer on the base station side do not change. However, due to the change in the cell serving the terminal, the terminal's MAC layer needs to be reset and the PHY layer needs to be reconfigured.

[0075] (2) Intra-CU, Inter-DU switching

[0076] The terminal switches between cells in different DUs under the same CU. As shown in Figure 3B, when the terminal switches from a cell in DU1 to a cell in DU2, the RLC and MAC entities on the base station side have changed. Therefore, the terminal's RLC layer needs to be rebuilt, the MAC layer needs to be reset, the PHY layer needs to be reconfigured, and the PDCP layer needs to perform data recovery under the Acknowledged Mode (AM) bearer. Incomplete data packets are retransmitted at the PDCP layer.

[0077] (3) Inter-CU switching

[0078] The terminal switches between different CUs (different gNBs). As shown in Figure 3C, the terminal switches from DU1 of CU1 to DU2 of CU2. This requires reestablishing the RLC layer, resetting the MAC layer, reconfiguring the PHY layer, changing the PDCP entity, and changing the key, thus requiring the PDCP layer to be reestablished. For inter-CU handovers, before each handover, the source cell must derive new keys for the candidate inter-CU cells and reconfigure the terminal.

[0079] 2. Long-Term Transaction (LTM)

[0080] To reduce handover latency, Release 18 introduced LTM. The DU uses L1 / L2 signaling to instruct the terminal to switch to a suitable candidate cell based on the Layer 1 measurement results reported by the terminal. R18 LTM only supports cell handover within the same CU.

[0081] R18 supports continuous Intra-CU LTM switching, where the terminal switches continuously between multiple configured candidate cells without the network having to reconfigure the candidate cells.

[0082] R19 LTM studies inter-CU LTM cell handover. It also studies conditional LTM, where the terminal triggers LTM handover based on conditional evaluation.

[0083] 3. Conditional Handoff (CHO)

[0084] The network pre-configures the CHO configuration for the terminal, and the terminal evaluates whether the execution conditions are met. Once the execution conditions are met, the terminal will apply the pre-configured target Master Cell Group (MCG) configuration and perform primary cell (PCell) handover.

[0085] During the CHO handover preparation process, for key derivation, if the source gNB has an unused {NH, NCC} pair, the source gNB will derive the key of each candidate target cell based on the NH, the physical cell identifier (PCI) and the frequency of the target cell; if there is no unused {NH, NCC} pair, the source gNB will derive the key of each candidate target cell based on the currently activated Kg NB , using the PCI and frequency of the target cell as input to get the key of each candidate target cell. The key of the candidate target cell is based on the same NH or Kg NB The only difference is the input parameters (PCI, frequency). NH refers to the next hop, NCC refers to the next hop chaining counter, and Kg NB Refers to the serving cell key.

[0086] After the CHO handover is completed, all CHO candidate cell configurations need to be released. The next CHO handover needs to be prepared again, and the keys of each candidate target cell are derived based on the new source cell key.

[0087] The following describes in detail the cell switching processing method provided by the embodiment of the present application through some embodiments and their application scenarios in combination with the accompanying drawings.

[0088] As can be seen above, in the existing CHO handover process, all CHO configurations must be released after the handover is completed, and continuous CHO handovers cannot be supported. Regarding LTM, Rel-18 only supports continuous LTM handovers within an intra-CU. In Rel-19, when an inter-CU LTM handover occurs, whether continuous LTM is supported, which candidate cells need to be released, and how to release them remain unresolved. When an inter-CU LTM handover occurs, how to handle the LTM handover remains to be determined.

[0089] In an embodiment of the present application, a solution is provided, whereby after executing a handover to a target cell, the terminal may release or retain at least part of the LTM candidate cell configuration according to a first rule, wherein the first rule includes whether the target cell satisfies a first condition, or includes indication information sent by the target cell. In this solution, the terminal may determine whether the handover is an Inter-CU handover by judging whether the target cell satisfies the first condition, and decide the LTM candidate cell configuration that needs to be released or retained according to the judgment result; or, the terminal may decide the LTM candidate cell configuration that needs to be released or retained according to the indication information sent by the target cell, wherein the indication information is sent to the terminal after the target CU judges whether the handover is an Inter-CU handover. In this way, after the Inter-CU handover occurs, the terminal may decide autonomously or according to the indication information to release or retain at least part of the LTM candidate cell configuration, thereby avoiding subsequent handover to an unavailable LTM candidate cell, thereby avoiding wireless link failure of the terminal and improving the accuracy of cell handover.

[0090] In another solution, when the target CU confirms that the terminal has switched to the target cell, it sends a second message to the target DU, and the second message includes at least one of the following: a second indication message indicating to stop sending the LTM switching command to the terminal, and an identification list of candidate target cells. In this solution, after the Inter-CU switching occurs, the target CU sends an indication to the target DU to stop sending the LTM switching command to the terminal, so that the target DU stops issuing the switching command to switch to other CUs, or the target CU sends an identification list of candidate target cells to the target DU, so that the terminal can switch to the candidate target cell corresponding to the identification list. In this way, the full continuity of the Inter-CU switching is achieved, so that the terminal can continue to switch to the corresponding candidate cell, avoiding the failure of the terminal's wireless link and improving the accuracy of the cell switching.

[0091] It should be noted that the embodiments of the present application can be applied to base stations with separate CUs and DUs, as well as base stations with integrated CUs and DUs. In the case of integrated CUs and DUs, the source CU and source DU both refer to the source gNB, and the target CU and target DU both refer to the target gNB.

[0092] The Inter-CU continuous switching described in the embodiment of the present application refers to: switching from a cell corresponding to one CU to a cell corresponding to another CU, and then switching from a cell corresponding to the other CU to another cell corresponding to the one CU. For example, assuming switching from CU1 to CU2, the cells corresponding to CU1 are cell 1 and cell 2, and the cells corresponding to CU2 are cell 3 and cell 4. Then, Inter-CU continuous switching refers to: switching from cell 1 corresponding to CU1 to cell 3 corresponding to CU2, and then switching from cell 3 corresponding to CU2 to cell 2 corresponding to CU1, and then switching from cell 2 corresponding to CU1 to cell 4 corresponding to CU2. It should be noted that the cell corresponding to the CU here can be the cell included in the same DU corresponding to the CU, or it can also be the cell included in different DUs corresponding to the CU, or it can also be the cell included in the same DU corresponding to the CU and the cell included in different DUs.

[0093] The present invention provides a method for processing a cell handover, and Figure 4 shows a flow chart of the method for processing a cell handover provided by the present invention. As shown in Figure 4, the method for processing a cell handover provided by the present invention may include the following steps 201 and 202.

[0094] Step 201: The terminal obtains at least one LTM candidate cell configuration.

[0095] In an embodiment of the present application, the terminal may receive at least one LTM candidate cell configuration from a source CU.

[0096] In this embodiment of the present application, an LTM candidate cell configuration includes: a portion of the LTM candidate cell configuration generated by a CU and a portion of the LTM candidate cell configuration generated by a DU. The DU is the DU under the CU. For example, LTM candidate cell configuration 1 includes: a portion of the LTM candidate cell configuration generated by CU1 and another portion of the LTM candidate cell configuration generated by DU1 under CU1.

[0097] Optionally, in the embodiment of the present application, there are three situations for configuring the at least one LTM candidate cell:

[0098] Case 1: All LTM candidate cells have the same CU and DU.

[0099] It can be understood that one CU corresponds to at least one DU, and one DU includes at least one cell.

[0100] In this case, the at least one LTM candidate cell configuration is generated by the same CU as a part of the configuration of each LTM candidate cell, and the other part of the configuration of each LTM candidate cell is generated by a DU under the same CU.

[0101] For example, assume that the at least one LTM candidate cell configuration is three LTM candidate cell configurations; CU1 corresponds to DU1, and DU1 includes cells 1 to 3. Then, LTM candidate cell configuration 1 includes: a portion of the configuration of LTM candidate cell 1 generated by CU1 and another portion of the configuration of LTM candidate cell 1 generated by DU1; LTM candidate cell configuration 2 includes: a portion of the configuration of LTM candidate cell 2 generated by CU1 and another portion of the configuration of LTM candidate cell 2 generated by DU1; and LTM candidate cell configuration 3 includes: a portion of the configuration of LTM candidate cell 3 generated by CU1 and another portion of the configuration of LTM candidate cell 3 generated by DU1.

[0102] Case 2: All LTM candidate cells have the same CU configured and at least some DUs are different.

[0103] In this case, the at least one LTM candidate cell configuration is generated by the same CU as a part of the configuration of each LTM candidate cell, and another part of the configuration of each LTM candidate cell is generated by different DUs under the same CU.

[0104] For example, assume that the at least one LTM candidate cell configuration is three LTM candidate cell configurations; CU1 corresponds to DU1 and DU2, DU1 includes cell 1 and cell 2, and DU2 includes cell 3. Then, LTM candidate cell configuration 1 includes: a portion of the configuration of LTM candidate cell 1 generated by CU1 and another portion of the configuration of LTM candidate cell 1 generated by DU1; LTM candidate cell configuration 2 includes: a portion of the configuration of LTM candidate cell 2 generated by CU1 and another portion of the configuration of LTM candidate cell 2 generated by DU1; and LTM candidate cell configuration 3 includes: a portion of the configuration of LTM candidate cell 3 generated by CU1 and another portion of the configuration of LTM candidate cell 3 generated by DU2.

[0105] For another example, assume that the at least one LTM candidate cell configuration is three LTM candidate cell configurations; CU1 corresponds to DU1, DU2, and DU3, where DU1 includes cell 1, DU2 includes cell 2, and DU3 includes cell 3. Then, LTM candidate cell configuration 1 includes: a portion of the configuration of LTM candidate cell 1 generated by CU1 and another portion of the configuration of LTM candidate cell 1 generated by DU1; LTM candidate cell configuration 2 includes: a portion of the configuration of LTM candidate cell 2 generated by CU1 and another portion of the configuration of LTM candidate cell 2 generated by DU2; and LTM candidate cell configuration 3 includes: a portion of the configuration of LTM candidate cell 3 generated by CU1 and another portion of the configuration of LTM candidate cell 3 generated by DU3.

[0106] Case 3: All LTM candidate cells have different CUs and DUs.

[0107] In this case, the at least one LTM candidate cell configuration is generated by different CUs as a part of the configuration of each LTM candidate cell, and the DU under each CU generates another part of the configuration of each LTM candidate cell.

[0108] For example, assume that the at least one LTM candidate cell configuration is two LTM candidate cell configurations; CU1 corresponds to DU1, CU2 corresponds to DU2, DU1 includes cell 1, and DU2 includes cell 2. Then, LTM candidate cell configuration 1 includes: a portion of the configuration of LTM candidate cell 1 generated by CU1 and another portion of the configuration of LTM candidate cell 1 generated by DU1; LTM candidate cell configuration 2 includes: a portion of the configuration of LTM candidate cell 2 generated by CU2 and another portion of the configuration of LTM candidate cell 2 generated by DU2.

[0109] Optionally, in the embodiment of the present application, the LTM candidate cell configuration includes at least one of the following:

[0110] Layer 1 measurement configuration associated with the LTM candidate cell;

[0111] The cell configuration applied when the terminal accesses the LTM candidate cell;

[0112] Transmission Configuration Indicator (TCI) status configuration associated with the LTM candidate cell;

[0113] The Random Access Channel (RACH) configuration associated with the LTM candidate cell.

[0114] Optionally, in an embodiment of the present application, for conditional LTM, each LTM candidate cell configuration is associated with one or more execution conditions.

[0115] Optionally, in an embodiment of the present application, each candidate cell configuration includes or is associated with a first identifier, and the first identifier is used to determine whether to perform PDCP reconstruction and key change during switching.

[0116] Optionally, in an embodiment of the present application, each candidate cell configuration belongs to a first list, and the first list is used to determine whether to perform PDCP reconstruction and key change during switching.

[0117] Step 202: When the terminal is handed over to the target cell, the terminal releases or retains at least part of the at least one LTM candidate cell configuration according to the first rule.

[0118] In the embodiment of the present application, the first rule includes any one of the following:

[0119] Whether the target cell meets the first condition;

[0120] Indication information sent by the target cell.

[0121] Optionally, in the embodiment of the present application, the first condition includes at least one of the following:

[0122] The target cell and the source cell have the same first identifier, which is used to determine whether to perform PDCP re-establishment and key change during handover;

[0123] The target cell and the source cell are in the same first list, which is used to determine whether to perform PDCP re-establishment and key change during handover;

[0124] The primary cell configuration or primary cell group configuration of the target cell does not include a master key change indication, which is used to indicate that the terminal needs to change the master key during the handover process of the primary cell to the target cell;

[0125] The primary and secondary cell configuration or the secondary cell group configuration of the target cell does not include a secondary key change indication, which is used to indicate that the terminal needs to change the secondary key during the handover process from the primary and secondary cell to the target cell.

[0126] It should be noted that when the source cell is a PCell, the LTM candidate cell configurations released by the terminal are all candidate PCell configurations. When the source cell is a Primary Secondary Cell (PSCell), the LTM candidate cell configurations released by the terminal are all candidate PSCell configurations.

[0127] Optionally, in one embodiment of the present application, the first rule includes whether the target cell satisfies the first condition. The step 202 may be implemented by any one of the following steps 202a to 202c.

[0128] Step 202a: When the target cell meets the first condition, the terminal retains all LTM candidate cell configurations in the at least one LTM candidate cell configuration.

[0129] It can be understood that when the target cell meets the first condition, the terminal determines that the LTM handover is the Intra-CU LTM handover, and thus all LTM candidate cell configurations can be retained.

[0130] Step 202b: If the target cell does not meet the first condition, the terminal releases all LTM candidate cell configurations in the at least one LTM candidate cell configuration.

[0131] It can be understood that when the target cell does not meet the first condition, the terminal determines that the LTM handover is an Inter-CU LTM handover, and thus all LTM candidate cell configurations can be released.

[0132] In an embodiment of the present application, the terminal can determine whether the LTM handover is an Inter-CU handover based on whether the target cell meets the first condition. If it is an Inter-CU handover, the LTM handover cannot be executed continuously, and the terminal releases all LTM candidate cell configurations to avoid subsequent switching to an unavailable LTM candidate cell.

[0133] It can be understood that for the case where continuous Inter-CU LTM switching is not supported, the terminal can automatically release all LTM candidate cell configurations after the Inter-CU switching is completed.

[0134] Step 202c: If the target cell does not meet the first condition, the terminal retains the LTM candidate cell configuration that meets the second condition or the third condition in at least one LTM candidate cell configuration, and releases the remaining LTM candidate cell configurations.

[0135] In the embodiment of the present application, the second condition includes at least one of the following: having the same first identifier as the target cell, being in the same first list as the target cell. The third condition includes at least one of the following: having a different first identifier than the source cell, being in a different first list than the source cell.

[0136] In an embodiment of the present application, the terminal can determine whether the LTM handover is an Inter-CU handover based on whether the target cell meets the first condition. If it is an Inter-CU handover, the subsequent Inter-CU handover cannot be continued, but the Intra-CU handover can continue. The terminal can release the LTM candidate cell configurations of all Inter-CUs, such as releasing the LTM candidate cell configurations that do not meet the second condition or the third condition, to avoid subsequent switching to unavailable LTM candidate cells.

[0137] It can be understood that for inter-CU LTM switching that supports partial continuity, after the inter-CU switching is completed, the terminal can determine the CU change and automatically release the LTM candidate cell configuration provided by the CU other than the target CU (a CU different from the target cell), that is, the above-mentioned LTM candidate cell configuration that does not meet the second or third conditions.

[0138] Optionally, in another embodiment of the present application, the first rule includes indication information. The step 202 may be implemented by any one of the following steps 202d to 202f.

[0139] Step 202d: Upon receiving the first indication information, the terminal releases all LTM candidate cell configurations in the at least one LTM candidate cell configuration.

[0140] The first indication information is used to instruct the terminal to release all LTM candidate cell configurations.

[0141] It can be understood that for inter-CU LTM switching that is not supported continuously, after the inter-CU switching is completed, the target CU instructs the UE to release all LTM candidate cell configurations.

[0142] In an embodiment of the present application, the target CU determines whether the LTM handover is an Inter-CU handover. If it is an Inter-CU handover, the LTM handover cannot be executed continuously. The target cell or target CU instructs the terminal to release all LTM candidate cell configurations to avoid subsequent switching to an unavailable LTM candidate cell.

[0143] Step 202e: The terminal releases at least part of the at least one LTM candidate cell configuration according to the second indication information.

[0144] The second indication information is used to indicate the configuration of the LTM candidate cell to be released.

[0145] Optionally, in an embodiment of the present application, the second indication information includes an identifier of the LTM candidate cell configuration to be released. Alternatively, the second indication information instructs the terminal to release the LTM candidate cell configuration that satisfies a fourth condition, where the fourth condition includes at least one of the following: the candidate cell and the target cell have different first identifiers, or the candidate cell and the target cell are in different first lists.

[0146] It can be understood that, when the second indication information includes identifiers of the LTM candidate cell configurations to be released, the terminal can release the LTM candidate cell configurations corresponding to these identifiers and retain the remaining LTM candidate cell configurations. Alternatively, when the second indication information instructs the terminal to release the LTM candidate cell configurations that meet the fourth condition, the terminal can release the LTM candidate cell configurations that meet the fourth condition and retain the remaining LTM candidate cell configurations.

[0147] In an embodiment of the present application, the target CU can determine whether the LTM handover is an Inter-CU handover. If it is an Inter-CU handover, the subsequent Inter-CU handover cannot be continued, but the Intra-CU handover can continue. The target cell or target CU can instruct the terminal to release the LTM candidate cell configuration of all Inter-CUs, such as indicating the LTM candidate cell configuration to be released through the second indication information, so as to avoid subsequent switching to an unavailable LTM candidate cell.

[0148] It can be understood that for inter-CU LTM switching that supports partial continuity, after the inter-CU switching is completed, the target CU instructs the terminal to release the LTM candidate cell configuration provided by CUs other than the target CU, and retain the candidate cell configuration of the target CU for subsequent intra-CU switching.

[0149] Step 202f: The terminal retains at least part of the at least one LTM candidate cell configuration according to the third indication information.

[0150] The third indication information is used to indicate the LTM candidate cell configuration that needs to be retained.

[0151] Optionally, in an embodiment of the present application, the third indication information includes an identifier of the LTM candidate cell configuration to be retained. Alternatively, the third indication information instructs the terminal to retain the LTM candidate cell configuration that satisfies a fifth condition, where the fifth condition includes at least one of the following: the candidate cell and the target cell have the same first identifier, and the candidate cell and the target cell are in the same first list.

[0152] It can be understood that, if the third indication information includes identifiers of LTM candidate cell configurations that need to be retained, the terminal can retain the LTM candidate cell configurations corresponding to these identifiers and release the remaining LTM candidate cell configurations. Alternatively, if the third indication information instructs the terminal to retain the LTM candidate cell configurations that meet the fifth condition, the terminal can retain the LTM candidate cell configurations that meet the fifth condition and release the remaining LTM candidate cell configurations.

[0153] In an embodiment of the present application, the target CU can determine whether the LTM handover is an Inter-CU handover. If it is an Inter-CU handover, the subsequent Inter-CU handover cannot be continued, but the Intra-CU handover can be continued. The target cell or target CU can instruct the terminal to retain the candidate cell configuration of the target CU for subsequent Intra-CU handover, such as the LTM candidate cell configuration that needs to be retained as indicated by the third indication information, and release the LTM candidate cell configuration provided by CUs other than the target CU to avoid subsequent switching to unavailable LTM candidate cells.

[0154] Optionally, in an embodiment of the present application, before the above step 202, the cell handover processing method provided in the embodiment of the present application may further include at least one of the following steps 203a to 203c.

[0155] Step 203a: When receiving the LTM handover command or the first execution condition is met, the terminal determines the LTM candidate cell configuration of the target cell from at least one LTM candidate cell configuration, and performs LTM handover to the target cell according to the LTM candidate cell configuration of the target cell.

[0156] In an embodiment of the present application, the above-mentioned LTM switching command includes an identifier of the target cell or the target cell configuration, and the above-mentioned first execution condition is an execution condition of the LTM switching.

[0157] Optionally, in an embodiment of the present application, after receiving an LTM handover command (LTM Command MAC CE) from a source DU, the terminal may perform LTM handover. Alternatively, the terminal may evaluate an execution condition and perform LTM handover if the condition is met.

[0158] Step 203b: Upon receiving the layer 3 handover command, the terminal performs layer 3 handover to the target cell.

[0159] In the embodiment of the present application, the above-mentioned layer 3 handover command includes the identifier of the target cell.

[0160] Step 203c: When the second execution condition is met, the terminal performs conditional handover to the target cell.

[0161] In the embodiment of the present application, the second execution condition is the execution condition of CHO.

[0162] Optionally, in an embodiment of the present application, the above-mentioned execution conditions may include at least one of the following: the serving cell quality is higher than the threshold, the serving cell quality is lower than the threshold, the candidate cell quality is higher than the serving cell by an offset value, and the candidate cell quality is higher than the threshold.

[0163] An embodiment of the present application provides a method for processing cell switching. After switching to the target cell, the terminal can release or retain at least part of the LTM candidate cell configuration according to a first rule. The first rule includes whether the target cell meets the first condition, or includes indication information sent by the target cell. In this solution, the terminal can determine whether the switch is an Inter-CU switch by judging whether the target cell meets the first condition, and decide the LTM candidate cell configuration that needs to be released or retained according to the judgment result; or the terminal can decide the LTM candidate cell configuration that needs to be released or retained according to the indication information sent by the target cell. The indication information is sent to the terminal after the target CU determines whether the switch is an Inter-CU switch. In this way, after the Inter-CU switch occurs, the terminal can decide independently or according to the indication of the indication information to release or retain at least part of the LTM candidate cell configuration, which can avoid subsequent switching to an unavailable LTM candidate cell, thereby avoiding the failure of the terminal's wireless link and improving the accuracy of the cell switch.

[0164] The present invention also provides a method for processing a cell handover. FIG5 shows a flowchart of the method for processing a cell handover provided by the present invention. As shown in FIG5 , the method for processing a cell handover provided by the present invention may include the following steps 301 to 304.

[0165] Step 301: The terminal obtains at least one LTM candidate cell configuration.

[0166] Step 302: The terminal performs handover to the target cell.

[0167] It should be noted that, for the relevant description of the above-mentioned step 301 and step 302, reference can be made to the description in the above-mentioned embodiment, which will not be repeated here.

[0168] Step 303: When confirming that the terminal switches to the target cell, the target CU sends an indication message to the terminal.

[0169] In the embodiment of the present application, the above-mentioned indication information is used to release or retain at least part of the LTM candidate cell configuration in at least one LTM candidate cell configuration.

[0170] Step 304: The terminal receives the indication information from the target CU, and releases or retains at least part of the at least one LTM candidate cell configuration according to the indication information.

[0171] Optionally, in an embodiment of the present application, the indication information is used to indicate an LTM candidate cell configuration to be released. The indication information includes an identifier of the LTM candidate cell configuration to be released; or the indication information instructs the terminal to release an LTM candidate cell configuration that meets a fourth condition, wherein the fourth condition includes at least one of the following: the candidate cell and the target cell have different first identifiers, or the candidate cell and the target cell are in different first lists. The first identifier or first list is used to determine whether to perform PDCP re-establishment and key change during handover.

[0172] Optionally, in this embodiment of the present application, the indication information is used to indicate an LTM candidate cell configuration that needs to be retained. The indication information includes an identifier of the LTM candidate cell configuration that needs to be retained; or the indication information instructs the terminal to retain an LTM candidate cell configuration that meets a fifth condition, wherein the fifth condition includes at least one of the following: the candidate cell and the target cell have the same first identifier, or the candidate cell and the target cell are in the same first list. This first identifier or first list is used to determine whether to perform PDCP re-establishment and key change during handover.

[0173] Optionally, the cell handover processing method provided in the embodiment of the present application further includes the following step 305.

[0174] Step 305: The target CU determines the identifier of the LTM candidate cell configuration to be released or to be retained according to the first information from the source CU.

[0175] In this embodiment of the present application, the first information includes at least one of the following:

[0176] Configuration identifier of each LTM candidate cell;

[0177] The PCI and frequency associated with the configuration identifier of each LTM candidate cell;

[0178] The Cell Global Identifier (CGI) associated with the configuration identifier of each LTM candidate cell;

[0179] The first identifier associated with each LTM candidate cell;

[0180] The identifier of the first list to which each LTM candidate cell belongs.

[0181] In this embodiment of the present application, the source CU may send the first information to all LTM candidate cells or all candidate CUs, where all LTM candidate cells are LTM candidate cells configured by the source CU for the terminal. Alternatively, the source CU may send the first information to the target cell or target CU. Thus, the target CU determines, based on the first information, the identifiers of the LTM candidate cell configurations to be released or retained, and sends the above-mentioned indication information to the terminal.

[0182] It should be noted that the above step 305 may be performed before the above step 303, or may be performed after confirming that the terminal has switched to the target cell and before sending the first indication information to the terminal.

[0183] Optionally, in the embodiment of the present application, the “sending instruction information to the terminal” in the above step 303 can be specifically implemented through the following step 303a.

[0184] Step 303a: When the target cell does not meet the first condition, the target CU sends indication information to the terminal.

[0185] In the embodiment of the present application, the first condition includes at least one of the following:

[0186] The target cell and the source cell have the same first identifier, and the first identifier is used to determine whether to perform PDCP re-establishment and key change during handover;

[0187] The target cell and the source cell are in the same first list, and the first list is used to determine whether to perform PDCP re-establishment and key change during handover;

[0188] The primary cell configuration or primary cell group configuration of the target cell does not include a master key change indication. The master key change indication is used to indicate that the terminal needs to change the master key during the handover process between the primary cell and the target cell;

[0189] The primary and secondary cell configuration or secondary cell group configuration of the target cell does not include a secondary key change indication, which is used to indicate that the terminal needs to change the secondary key during the handover process from the primary and secondary cell to the target cell.

[0190] It can be understood that when the target cell does not meet the first condition, the target CU determines that the switch is an Inter-CU switch, then the LTM switch cannot be executed continuously, and the target CU can send an indication message to the terminal to instruct the terminal to release or retain the LTM candidate cell configuration to avoid subsequent switching to an unavailable LTM candidate cell.

[0191] It should be noted that the specific solution of how the indication information instructs the terminal to release or retain the LTM candidate cell configuration is described in the above embodiment and will not be repeated here.

[0192] Optionally, in the embodiment of the present application, the “sending instruction information to the terminal” in the above step 303 or step 303a can be specifically implemented through the following step 303b.

[0193] Step 303b: The target CU sends indication information to the terminal through an RRC reconfiguration message or a Media Access Control-Control Element (MAC CE) signaling.

[0194] An embodiment of the present application provides a method for processing cell handover, in which the target CU sends an indication message to the terminal after confirming that the terminal has completed handover to the target cell, so that the terminal can release or retain at least part of the LTM candidate cell configuration according to the indication message. In this solution, after the Inter-CU handover occurs, the target CU can indicate to the terminal through the indication message the LTM candidate cell configuration to be released or retained, so that the terminal can decide the LTM candidate cell configuration that needs to be released or retained according to the indication message, thereby avoiding subsequent handover to an unavailable LTM candidate cell, avoiding the failure of the terminal's wireless link, and improving the accuracy of cell handover.

[0195] The present invention also provides a method for processing a cell handover. FIG6 shows a flowchart of the method for processing a cell handover provided by the present invention. As shown in FIG6, the method for processing a cell handover provided by the present invention may include the following steps 401 to 403.

[0196] Step 401: A source CU sends first information to a first CU.

[0197] In the embodiment of the present application, the first CU is all candidate CUs or target CUs. The first information is used by the target CU to send first indication information to the terminal, and the indication information is used to release or retain at least part of the at least one LTM candidate cell configuration.

[0198] In this embodiment of the present application, the first information includes at least one of the following:

[0199] Configuration identifier of each LTM candidate cell;

[0200] The PCI and frequency associated with the configuration identifier of each LTM candidate cell;

[0201] The CGI associated with the configuration identifier of each LTM candidate cell;

[0202] The first identifier associated with each LTM candidate cell;

[0203] The identifier of the first list to which each LTM candidate cell belongs.

[0204] Optionally, in an embodiment of the present application, the above step 401 can be specifically implemented through the following step 401a or step 401b.

[0205] Step 401a: Before initiating LTM switching, the source CU sends first information to all candidate CUs.

[0206] It can be understood that during the switching preparation process, the source CU can send the first information to all candidate CUs.

[0207] Step 401b: When the LTM switching is initiated or the LTM switching is completed, the source CU sends the first information to the target CU.

[0208] In the embodiment of the present application, the above-mentioned initiation of LTM switching can be understood as after the LTM switching command is sent.

[0209] Step 402: The target CU sends first indication information to the terminal according to the first information.

[0210] In an embodiment of the present application, the target CU can determine the identifier of the LTM candidate cell configuration to be released or to be retained based on the first information, and send the above-mentioned indication information to the terminal to instruct the terminal to release or retain the LTM candidate cell configuration to avoid subsequent switching to an unavailable LTM candidate cell.

[0211] Step 403: The terminal receives the indication information from the target CU, and releases or retains at least part of the at least one LTM candidate cell configuration according to the indication information.

[0212] Optionally, in an embodiment of the present application, the indication information is used to indicate an LTM candidate cell configuration to be released. The indication information includes an identifier of the LTM candidate cell configuration to be released; or the indication information instructs the terminal to release an LTM candidate cell configuration that meets a fourth condition, wherein the fourth condition includes at least one of the following: the candidate cell and the target cell have different first identifiers, or the candidate cell and the target cell are in different first lists. The first identifier or first list is used to determine whether to perform PDCP re-establishment and key change during handover.

[0213] Optionally, in this embodiment of the present application, the indication information is used to indicate an LTM candidate cell configuration that needs to be retained. The indication information includes an identifier of the LTM candidate cell configuration that needs to be retained; or the indication information instructs the terminal to retain an LTM candidate cell configuration that meets a fifth condition, wherein the fifth condition includes at least one of the following: the candidate cell and the target cell have the same first identifier, or the candidate cell and the target cell are in the same first list. This first identifier or first list is used to determine whether to perform PDCP re-establishment and key change during handover.

[0214] It should be noted that the specific solution of the above-mentioned indication information instructing the terminal to release or retain the LTM candidate cell configuration can be found in the description of the above-mentioned embodiment and will not be repeated here.

[0215] Optionally, the cell handover processing method provided in the embodiment of the present application further includes the following step 404.

[0216] Step 404: The source CU sends at least one LTM candidate cell configuration to the terminal.

[0217] In the embodiment of the present application, the LTM candidate cell configuration includes at least one of the following:

[0218] Layer 1 measurement configuration associated with the LTM candidate cell;

[0219] The cell configuration applied when the terminal accesses the LTM candidate cell;

[0220] TCI status configuration associated with LTM candidate cells;

[0221] RACH configuration associated with the LTM candidate cell.

[0222] It should be noted that the above step 404 can be performed before the above step 401.

[0223] An embodiment of the present application provides a method for processing cell switching, in which the source CU can send first information to all candidate CUs or target CUs, so that the target CU can send first indication information to the terminal, so that the terminal releases or retains at least part of the LTM candidate cell configuration. In this solution, the source CU can send first information to all candidate CUs or target CUs, so that the target CU can determine the identifier of the LTM candidate cell configuration to be released or retained based on the first information, so that after the Inter-CU LTM switching occurs, the indication information is sent to the terminal, so that the terminal can decide the LTM candidate cell configuration that needs to be released or retained based on the indication of the indication information, thereby avoiding subsequent switching to an unavailable LTM candidate cell, thereby avoiding the failure of the terminal's wireless link and improving the accuracy of cell switching.

[0224] The present invention also provides a method for processing a cell handover. FIG7 shows a flowchart of the method for processing a cell handover provided by the present invention. As shown in FIG7 , the method for processing a cell handover provided by the present invention may include the following steps 501 and 502.

[0225] Step 501: When confirming that the terminal has switched to the target cell, the target CU sends second information to the target DU.

[0226] Step 502: The target DU receives second information from the target CU.

[0227] In an embodiment of the present application, the source CU can provide at least one LTM candidate cell configuration for the terminal; the source DU can send an LTM switching command to the terminal, instructing the terminal to switch to the LTM target cell of the target CU; when the target CU confirms that the terminal has switched to the target cell, it sends a second message to the target DU.

[0228] In this embodiment of the present application, the second information includes at least one of the following:

[0229] The second instruction information is used to instruct to stop sending the LTM switching command to the terminal;

[0230] A list of identifiers of candidate target cells.

[0231] Optionally, in an embodiment of the present application, the above-mentioned candidate target cell identification list is used to indicate that the target DU is allowed to send an LTM switching command to the terminal, so that the terminal can switch to the candidate target cell corresponding to the identification list.

[0232] Optionally, in an embodiment of the present application, the above-mentioned candidate target cell identification list is used to instruct the target DU to stop sending LTM switching commands to the terminal, so that the terminal switches to the candidate target cell corresponding to the identification list.

[0233] It can be understood that after receiving the second indication information, the target DU can stop sending the LTM switching command (switching command to other CU) to the terminal, so that the terminal stops executing LTM switching to other CU until the key reconfiguration is completed.

[0234] After receiving the candidate target cell identifier list, the target DU may send an LTM handover command to the terminal to instruct the terminal to handover to the candidate target cell corresponding to the identifier list until the key reconfiguration is completed.

[0235] After receiving the candidate target cell identifier list, the target DU may stop sending the LTM switching command to the terminal, so that the terminal switches to the candidate target cell corresponding to the identifier list until the key reconfiguration is completed.

[0236] Optionally, in an embodiment of the present application, after the above step 502, the cell switching processing method provided in the embodiment of the present application further includes the following step 503.

[0237] Step 503: After completing the reconfiguration of the candidate cell key of the terminal, the target CU sends third information to the target DU.

[0238] In this embodiment of the present application, the third information includes at least one of the following:

[0239] The third indication information is used to instruct the target DU to resume or restart sending an LTM switching command to the terminal;

[0240] A second list of candidate target cells.

[0241] Optionally, in an embodiment of the present application, the above-mentioned second list is used to indicate that the target DU is allowed to send an LTM switching command to the terminal, so that the terminal can switch to the candidate target cell corresponding to the second list.

[0242] Optionally, in an embodiment of the present application, the above-mentioned second list is used to instruct the target DU to resume or restart sending an LTM switching command to the terminal, so that the terminal switches to the candidate target cell corresponding to the second list.

[0243] It can be understood that after receiving the third indication information, the target DU can resume or restart sending the LTM switching command (switching command to other CU) to the terminal, so that the terminal continues to perform LTM switching to other CU.

[0244] After receiving the second list of candidate target cells, the target DU may send an LTM handover command to the terminal to instruct the terminal to handover to the candidate target cell corresponding to the second list.

[0245] After receiving the second list of candidate target cells, the target DU may resume or restart sending the LTM switching command to the terminal, so that the terminal switches to the candidate target cell corresponding to the second list.

[0246] Optionally, in an embodiment of the present application, the second list may include an identifier list of candidate target cells, or may include a PCI and frequency (PCI+frequency) list.

[0247] In an embodiment of the present application, after the target CU sends the second information to the target DU, the target CU derives the candidate cell key and reconfigures the candidate cell key of the terminal; after the reconfiguration is completed, the target CU sends the third information to the target DU.

[0248] It can be understood that for supporting all continuous Inter-CU LTM switching, after the Inter-CU switching is completed, the target DU can stop sending switching commands to other CUs until the key reconfiguration is completed.

[0249] Optionally, in the embodiment of the present application, the cell switching processing method provided in the embodiment of the present application further includes the following step 504.

[0250] Step 504: The target CU determines a list of identifiers of candidate target cells according to the first information from the source CU.

[0251] In this embodiment of the present application, the first information includes at least one of the following:

[0252] Configuration identifier of each LTM candidate cell;

[0253] The PCI and frequency associated with the configuration identifier of each LTM candidate cell;

[0254] The CGI associated with the configuration identifier of each LTM candidate cell;

[0255] The first identifier associated with each LTM candidate cell;

[0256] The identifier of the first list to which each LTM candidate cell belongs.

[0257] Optionally, in an embodiment of the present application, before initiating an LTM handover (e.g., during handover preparation), the source CU may send first information to all candidate CUs. When initiating an LTM handover or when the LTM handover is completed, the source CU may send the first information to the target CU. Thus, the target CU determines a list of identifiers of candidate target cells based on the first information.

[0258] It should be noted that the above step 504 may be performed before the above step 501, or may be performed after confirming that the terminal has switched to the target cell and before sending the second information to the target DU.

[0259] An embodiment of the present application provides a method for processing cell switching, in which the target CU sends a second message to the target DU when confirming that the terminal has switched to the target cell. The second message includes at least one of the following: a second indication message indicating to stop sending the LTM switching command to the terminal, and an identification list of candidate target cells. In this solution, after the Inter-CU switching occurs, the target CU sends an indication to the target DU to stop sending the LTM switching command to the terminal, so that the target DU stops issuing the switching command to switch to other CUs, or the target CU sends an identification list of candidate target cells to the target DU, so that the terminal switches to the candidate target cell corresponding to the identification list. In this way, the full continuity of the Inter-CU switching is achieved, so that the terminal can continue to execute the switch to the corresponding candidate cell, which can avoid the failure of the terminal's wireless link, thereby improving the accuracy of the cell switching.

[0260] Each of the above-mentioned method embodiments, or various possible implementation methods in each method embodiment, can be executed separately, or any two or more of them can be executed in combination with each other. The specific implementation can be determined according to actual usage requirements, and the embodiments of this application do not limit this.

[0261] The cell handover processing method provided in the embodiment of the present application can be executed by a cell handover processing device. In the embodiment of the present application, the cell handover processing method performed by the cell handover processing device is taken as an example to illustrate the cell handover processing device provided in the embodiment of the present application.

[0262] FIG8 shows a possible structural diagram of a cell handover processing device involved in an embodiment of the present application. As shown in FIG8 , the cell handover processing device 40 may include: an acquisition module 41 and a processing module 42 .

[0263] The acquisition module 41 is configured to acquire at least one LTM candidate cell configuration. The processing module 42 is configured to release or retain at least part of the at least one LTM candidate cell configuration according to a first rule when switching to a target cell. The first rule includes any one of the following: whether the target cell satisfies a first condition; or indication information sent by the target cell.

[0264] An embodiment of the present application provides a cell handover processing device. The cell handover processing device can determine whether the handover is an Inter-CU handover by judging whether the target cell satisfies a first condition, and decides whether the LTM candidate cell configuration needs to be released or retained based on the judgment result; or the cell handover processing device can determine whether the LTM candidate cell configuration needs to be released or retained based on the indication of the indication information sent by the target cell. The indication information is sent by the target CU after determining whether the handover is an Inter-CU handover. In this way, after the Inter-CU handover occurs, the cell handover processing device can independently decide or release or retain at least part of the LTM candidate cell configuration based on the indication of the indication information, thereby avoiding subsequent switching to an unavailable LTM candidate cell, thereby avoiding wireless link failure of the cell handover processing device and improving the accuracy of the cell handover.

[0265] In one possible implementation, the first condition includes at least one of the following:

[0266] The target cell and the source cell have the same first identifier, which is used to determine whether to perform PDCP re-establishment and key change during handover;

[0267] The target cell and the source cell are in the same first list, which is used to determine whether to perform PDCP re-establishment and key change during handover;

[0268] The primary cell configuration or primary cell group configuration of the target cell does not include a master key change indication, which is used to indicate that the terminal needs to change the master key during the handover process of the primary cell to the target cell;

[0269] The primary and secondary cell configuration or the secondary cell group configuration of the target cell does not include a secondary key change indication, which is used to indicate that the terminal needs to change the secondary key during the handover process from the primary and secondary cell to the target cell.

[0270] In one possible implementation, the first rule includes whether the target cell satisfies the first condition; the processing module 42 is specifically used to: retain all LTM candidate cell configurations in at least one LTM candidate cell configuration when the target cell satisfies the first condition; or release all LTM candidate cell configurations in at least one LTM candidate cell configuration when the target cell does not satisfy the first condition.

[0271] In one possible implementation, the first rule includes whether the target cell satisfies the first condition; the processing module 42 is specifically configured to retain at least one LTM candidate cell configuration that satisfies the second condition or the third condition when the target cell does not satisfy the first condition, and release the remaining LTM candidate cell configurations; wherein the second condition includes at least one of the following: having the same first identifier as the target cell and being in the same first list as the target cell; the third condition includes at least one of the following: having a different first identifier from the source cell and being in a different first list from the source cell.

[0272] In one possible implementation, the first rule includes indication information; the processing module 42 is specifically used to release all LTM candidate cell configurations in at least one LTM candidate cell configuration upon receiving the first indication information, and the first indication information is used to instruct the terminal to release all LTM candidate cell configurations.

[0273] In one possible implementation, the first rule includes indication information; the processing module 42 is specifically used to release at least part of the LTM candidate cell configuration in at least one LTM candidate cell configuration according to the second indication information, and the second indication information is used to indicate the LTM candidate cell configuration to be released.

[0274] In one possible implementation, the second indication information includes an identifier of the LTM candidate cell configuration to be released; or, the second indication information instructs the terminal to release the LTM candidate cell configuration that meets the fourth condition, and the fourth condition includes at least one of the following: the candidate cell and the target cell have different first identifiers, and the candidate cell and the target cell are in different first lists.

[0275] In one possible implementation, the first rule includes first indication information; the processing module 42 is specifically used to retain at least part of the LTM candidate cell configuration in at least one LTM candidate cell configuration according to third indication information, and the third indication information is used to indicate the LTM candidate cell configuration that needs to be retained.

[0276] In one possible implementation, the third indication information includes an identifier of the LTM candidate cell configuration that needs to be retained; or, the third indication information instructs the terminal to retain the LTM candidate cell configuration that meets the fifth condition, and the fifth condition includes at least one of the following: the candidate cell and the target cell have the same first identifier, and the candidate cell and the target cell are in the same first list.

[0277] In one possible implementation, the above-mentioned LTM candidate cell configuration includes at least one of the following: a layer 1 measurement configuration associated with the LTM candidate cell; a cell configuration applied when the terminal accesses the LTM candidate cell; a TCI state configuration associated with the LTM candidate cell; and a RACH configuration associated with the LTM candidate cell.

[0278] In a possible implementation, the cell handover processing device 40 provided in the embodiment of the present application further includes an execution module. The execution module is configured to determine the LTM candidate cell configuration of the target cell from at least one LTM candidate cell configuration when an LTM handover command is received or a first execution condition is satisfied, and to perform LTM handover to the target cell according to the LTM candidate cell configuration of the target cell, wherein the LTM handover command includes an identifier of the target cell or the target cell configuration, and the first execution condition is an execution condition of the LTM handover. Alternatively, the execution module is configured to perform layer 3 handover to the target cell when a layer 3 handover command is received, wherein the layer 3 handover command includes an identifier of the target cell. Alternatively, the execution module is configured to perform conditional handover to the target cell when a second execution condition is satisfied, and the second execution condition is an execution condition of the CHO.

[0279] The cell handover processing device in the embodiment of the present application can be an electronic device, such as an electronic device with an operating system, or a component in an electronic device, such as an integrated circuit or chip. The electronic device can be a terminal, or it can be other devices other than a terminal. For example, the terminal can include but is not limited to the types of terminal 11 listed above, and other devices can be servers, network attached storage (NAS), etc., which are not specifically limited in the embodiment of the present application.

[0280] The cell switching processing device provided in the embodiment of the present application can implement the various processes implemented in the above-mentioned terminal side method embodiment and achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0281] FIG9 shows another possible structural diagram of a cell handover processing device involved in an embodiment of the present application. As shown in FIG9 , the cell handover processing device 50 may include: a sending module 51 .

[0282] The sending module 51 is configured to send first indication information to the terminal when confirming that the terminal has switched to the target cell; wherein the first indication information is used to release or retain at least part of the LTM candidate cell configuration in at least one LTM candidate cell configuration.

[0283] An embodiment of the present application provides a cell switching processing device. After an Inter-CU switching occurs, the cell switching processing device can indicate to the terminal through indication information whether to release or retain the LTM candidate cell configuration, so that the terminal can decide whether to release or retain the LTM candidate cell configuration according to the indication of the indication information, thereby avoiding subsequent switching to an unavailable LTM candidate cell, avoiding wireless link failure of the terminal, and improving the accuracy of cell LTM switching.

[0284] In one possible implementation, the indication information is used to indicate an LTM candidate cell configuration to be released. The indication information includes an identifier of the LTM candidate cell configuration to be released; or the indication information instructs the terminal to release an LTM candidate cell configuration that meets a fourth condition, the fourth condition comprising at least one of the following: the candidate cell and the target cell have different first identifiers, or the candidate cell and the target cell are in different first lists; the first identifier or the first list is used to determine whether to perform PDCP re-establishment and key change during handover.

[0285] In one possible implementation, the indication information is used to indicate an LTM candidate cell configuration that needs to be retained. The indication information includes an identifier of the LTM candidate cell configuration that needs to be retained; or the indication information instructs the terminal to retain an LTM candidate cell configuration that meets a fifth condition, the fifth condition comprising at least one of the following: the candidate cell and the target cell have the same first identifier, or the candidate cell and the target cell are in the same first list; the first identifier or the first list is used to determine whether to perform PDCP re-establishment and key change during handover.

[0286] In one possible implementation, as shown in FIG10 in conjunction with FIG9 , the cell handover processing device 50 provided in the embodiment of the present application further includes: a determination module 52. The determination module 52 is configured to determine, based on the first information from the source CU, an identifier of the LTM candidate cell configuration to be released or to be retained;

[0287] The first information includes at least one of the following:

[0288] Configuration identifier of each LTM candidate cell;

[0289] The PCI and frequency associated with the configuration identifier of each LTM candidate cell;

[0290] The CGI associated with the configuration identifier of each LTM candidate cell;

[0291] The first identifier associated with each LTM candidate cell;

[0292] The identifier of the first list to which each LTM candidate cell belongs.

[0293] In a possible implementation, the sending module 51 is specifically configured to send indication information to the terminal when the target cell does not meet the first condition; wherein the first condition includes at least one of the following:

[0294] The target cell and the source cell have the same first identifier, which is used to determine whether to perform PDCP re-establishment and key change during handover;

[0295] The target cell and the source cell are in the same first list, which is used to determine whether to perform PDCP re-establishment and key change during handover;

[0296] The primary cell configuration or primary cell group configuration of the target cell does not include a master key change indication, which is used to indicate that the terminal needs to change the master key during the handover process of the primary cell to the target cell;

[0297] The primary and secondary cell configuration or the secondary cell group configuration of the target cell does not include a secondary key change indication, which is used to indicate that the terminal needs to change the secondary key during the handover process from the primary and secondary cell to the target cell.

[0298] In a possible implementation, the sending module 51 is specifically configured to send indication information to the terminal via an RRC reconfiguration message or a MAC CE signaling.

[0299] In one possible implementation, the above-mentioned LTM candidate cell configuration includes at least one of the following: a layer 1 measurement configuration associated with the LTM candidate cell; a cell configuration applied when the terminal accesses the LTM candidate cell; a TCI state configuration associated with the LTM candidate cell; and a RACH configuration associated with the LTM candidate cell.

[0300] The cell switching processing device provided in the embodiment of the present application can implement the various processes implemented in the above-mentioned target CU side method embodiment and achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0301] FIG11 shows another possible structural diagram of a cell handover processing device involved in an embodiment of the present application. As shown in FIG11 , the cell handover processing device 60 may include: a sending module 61 .

[0302] The sending module 61 is configured to send first information to a first CU, where the first CU is all candidate CUs or a target CU. The first information is used by the target CU to send indication information to the terminal, where the indication information is used to release or retain at least part of the at least one LTM candidate cell configuration. The first information includes at least one of the following:

[0303] Configuration identifier of each LTM candidate cell;

[0304] The PCI and frequency associated with the configuration identifier of each LTM candidate cell;

[0305] The CGI associated with the configuration identifier of each LTM candidate cell;

[0306] The first identifier associated with each LTM candidate cell;

[0307] The identifier of the first list to which each LTM candidate cell belongs.

[0308] An embodiment of the present application provides a cell switching processing device, which can send first information to all candidate CUs or target CUs, so that the target CU can determine the identifier of the LTM candidate cell configuration to be released or to be retained based on the first information, and send first indication information to the terminal after the Inter-CU LTM switching occurs, so that the terminal can decide the LTM candidate cell configuration to be released or retained based on the indication of the indication information, thereby avoiding subsequent switching to an unavailable LTM candidate cell and improving the accuracy of LTM switching processing.

[0309] In a possible implementation, the sending module 61 is specifically configured to send the first information to all candidate CUs before initiating the LTM switch; or to send the first information to the target CU when initiating the LTM switch or when the LTM switch is completed.

[0310] In one possible implementation, the indication information is used to indicate an LTM candidate cell configuration to be released. The indication information includes an identifier of the LTM candidate cell configuration to be released; or the indication information instructs the terminal to release an LTM candidate cell configuration that meets a fourth condition, the fourth condition comprising at least one of the following: the candidate cell and the target cell have different first identifiers, or the candidate cell and the target cell are in different first lists; the first identifier or the first list is used to determine whether to perform PDCP re-establishment and key change during handover.

[0311] In one possible implementation, the indication information is used to indicate an LTM candidate cell configuration that needs to be retained. The indication information includes an identifier of the LTM candidate cell configuration that needs to be retained; or the indication information instructs the terminal to retain an LTM candidate cell configuration that meets a fifth condition, the fifth condition comprising at least one of the following: the candidate cell and the target cell have the same first identifier, or the candidate cell and the target cell are in the same first list; the first identifier or the first list is used to determine whether to perform PDCP re-establishment and key change during handover.

[0312] In a possible implementation, the sending module 61 is further configured to send at least one LTM candidate cell configuration to the terminal; wherein the LTM candidate cell configuration includes at least one of the following:

[0313] Layer 1 measurement configuration associated with the LTM candidate cell;

[0314] The cell configuration applied when the terminal accesses the LTM candidate cell;

[0315] TCI status configuration associated with LTM candidate cells;

[0316] RACH configuration associated with the LTM candidate cell.

[0317] The cell switching processing device provided in the embodiment of the present application can implement the various processes implemented in the above-mentioned source CU side method embodiment and achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0318] FIG12 shows another possible structural diagram of a cell handover processing device involved in an embodiment of the present application. As shown in FIG12 , the cell handover processing device 70 may include: a sending module 71 .

[0319] Among them, the sending module 71 is used to send second information to the target DU when confirming that the terminal switches to the target cell; wherein the second information includes at least one of the following: second indication information, used to instruct to stop sending the LTM switching command to the terminal; a list of identifiers of candidate target cells.

[0320] An embodiment of the present application provides a cell handover processing device. After an Inter-CU handover occurs, the cell handover processing device sends an instruction to the target DU to stop sending LTM handover commands to the terminal, so that the target DU stops issuing handover commands to switch to other CUs, or the cell handover processing device sends a list of identifiers of candidate target cells to the target DU, so that the terminal switches to the candidate target cells corresponding to the identifier list. This achieves full continuity of the Inter-CU LTM handover, so that the terminal can continue to execute the handover to the corresponding candidate cell, avoids the failure of the terminal's wireless link, and improves the accuracy of the cell handover.

[0321] In a possible implementation, the candidate target cell identifier list is used to indicate that the target DU is allowed to send an LTM handover command to the terminal, so that the terminal can switch to the candidate target cell corresponding to the identifier list;

[0322] or,

[0323] The above candidate target cell identifier list is used to instruct the target DU to stop sending the LTM handover command to the terminal, so that the terminal can switch to the candidate target cell corresponding to the identifier list.

[0324] In a possible implementation, the sending module 71 is further configured to, after sending the second information to the target DU, send third information to the target DU when the reconfiguration of the candidate cell key of the terminal is completed;

[0325] The third information includes at least one of the following:

[0326] The third indication information is used to instruct the target DU to resume or restart sending an LTM switching command to the terminal;

[0327] A second list of candidate target cells.

[0328] In a possible implementation, the second list is used to indicate that the target DU is allowed to send an LTM handover command to the terminal, so that the terminal can switch to the candidate target cell corresponding to the second list; or,

[0329] The second list is used to instruct the target DU to resume or restart sending an LTM switching command to the terminal, so that the terminal can switch to the candidate target cell corresponding to the second list.

[0330] In one possible implementation, as shown in FIG13 in conjunction with FIG12 , the cell handover processing device 70 provided in the embodiment of the present application further includes: a determination module 72. The determination module 72 is configured to determine a list of identifiers of candidate target cells based on the first information from the source CU;

[0331] Among them, the first information includes at least one of the following: the configuration identifier of each LTM candidate cell; the PCI and frequency associated with the configuration identifier of each LTM candidate cell; the CGI associated with the configuration identifier of each LTM candidate cell; the first identifier associated with each LTM candidate cell; and the identifier of the first list to which each LTM candidate cell belongs.

[0332] The cell switching processing device provided in the embodiment of the present application can implement the various processes implemented in the above-mentioned target CU side method embodiment and achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0333] As shown in Figure 14, an embodiment of the present application further provides a communication device 5000, including a processor 5001 and a memory 5002. The memory 5002 stores a program or instruction that can be run on the processor 5001. For example, when the communication device 5000 is a terminal, the program or instruction is executed by the processor 5001 to implement the various steps of the above-mentioned terminal-side method embodiment, and can achieve the same technical effect. To avoid repetition, it is not repeated here. When the communication device 5000 is a network-side device, the program or instruction is executed by the processor 5001 to implement the various steps of the above-mentioned target CU or source CU side method embodiment, and can achieve the same technical effect. To avoid repetition, it is not repeated here.

[0334] The present application also provides a terminal including a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is configured to execute a program or instruction to implement the steps in the above-mentioned cell handover processing method embodiment. This terminal embodiment corresponds to the above-mentioned terminal-side method embodiment, and each implementation process and implementation method of the above-mentioned method embodiment can be applied to this terminal embodiment and can achieve the same technical effect. Specifically, Figure 15 is a schematic diagram of the hardware structure of a terminal implementing an embodiment of the present application.

[0335] The terminal 7000 includes but is not limited to: a radio frequency unit 7001, a network module 7002, an audio output unit 7003, an input unit 7004, a sensor 7005, a display unit 7006, a user input unit 7007, an interface unit 7008, a memory 7009 and at least some of the components of the processor 7010.

[0336] Those skilled in the art will appreciate that the terminal 7000 may also include a power supply (such as a battery) to power various components. The power supply may be logically connected to the processor 7010 via a power management system, thereby enabling the power management system to manage charging, discharging, and power consumption. The terminal structure shown in FIG15 does not limit the terminal. The terminal may include more or fewer components than shown, or combine certain components, or arrange the components differently, which will not be described in detail here.

[0337] It should be understood that in an embodiment of the present application, the input unit 7004 may include a graphics processing unit (GPU) 70041 and a microphone 70042, and the graphics processor 70041 processes the image data of a static picture or video obtained by an image capture device (such as a camera) in a video capture mode or an image capture mode. The display unit 7006 may include a display panel 70061, and the display panel 70061 may be configured in the form of a liquid crystal display, an organic light emitting diode, etc. The user input unit 7007 includes a touch panel 70071 and at least one of other input devices 70072. The touch panel 70071 is also called a touch screen. The touch panel 70071 may include two parts: a touch detection device and a touch controller. Other input devices 70072 may include, but are not limited to, a physical keyboard, function keys (such as volume control keys, switch keys, etc.), a trackball, a mouse, and an operating stick, which will not be repeated here.

[0338] In the embodiment of the present application, after receiving downlink data from a network-side device, the RF unit 7001 may transmit the data to the processor 7010 for processing. Furthermore, the RF unit 7001 may send uplink data to the network-side device. Typically, the RF unit 7001 includes, but is not limited to, an antenna, an amplifier, a transceiver, a coupler, a low-noise amplifier, a duplexer, and the like.

[0339] The memory 7009 can be used to store software programs or instructions and various data. The memory 7009 may mainly include a first storage area for storing programs or instructions and a second storage area for storing data, wherein the first storage area may store an operating system, applications or instructions required for at least one function (such as a sound playback function, an image playback function, etc.). In addition, the memory 7009 may include a volatile memory or a non-volatile memory. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), a static random access memory (SRAM), a dynamic random access memory (DRAM), a synchronous dynamic random access memory (SDRAM), a double data rate synchronous dynamic random access memory (DDRSDRAM), an enhanced synchronous dynamic random access memory (ESDRAM), a synchronous link dynamic random access memory (SLDRAM), and a direct memory bus random access memory (DRRAM). The memory 7009 in the embodiment of the present application includes, but is not limited to, these and any other suitable types of memory.

[0340] The processor 7010 may include one or more processing units. Optionally, the processor 7010 integrates an application processor and a modem processor. The application processor primarily handles operations related to the operating system, user interface, and application programs, while the modem processor primarily processes wireless communication signals, such as a baseband processor. It is understood that the modem processor may not be integrated into the processor 7010.

[0341] The terminal provided in the embodiment of the present application can implement the various processes implemented by the terminal in the above-mentioned method embodiment and achieve the same technical effect. The implementation process of each implementation method mentioned in this embodiment can refer to the relevant description of the above-mentioned cell switching processing method embodiment. To avoid repetition, it will not be repeated here.

[0342] The present application also provides a network-side device, including a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is configured to execute a program or instruction to implement the steps of the above-mentioned cell handover processing method embodiment. This network-side device embodiment corresponds to the above-mentioned target CU or source CU side method embodiment, and each implementation process and implementation method of the above-mentioned method embodiment can be applied to this network-side device embodiment and can achieve the same technical effect.

[0343] Specifically, embodiments of the present application also provide a network-side device. As shown in Figure 16, the network-side device 600 includes an antenna 601, a radio frequency device 602, a baseband device 603, a processor 604, and a memory 605. Antenna 601 is connected to radio frequency device 602. In the uplink direction, radio frequency device 602 receives information via antenna 601 and sends the received information to baseband device 603 for processing. In the downlink direction, baseband device 603 processes the information to be transmitted and sends it to radio frequency device 602. Radio frequency device 602 processes the received information and then sends it through antenna 601.

[0344] The method executed by the network-side device in the above embodiment may be implemented in the baseband device 603 , which includes a baseband processor.

[0345] The baseband device 603 may include, for example, at least one baseband board, on which multiple chips are arranged, as shown in Figure 16, one of which is, for example, a baseband processor, which is connected to the memory 605 through a bus interface to call the program in the memory 605 and execute the network device operations shown in the above method embodiment.

[0346] The network side device may further include a network interface 606, which is, for example, a Common Public Radio Interface (CPRI).

[0347] Specifically, the network side device 600 of the embodiment of the present application also includes: instructions or programs stored in the memory 605 and executable on the processor 604. The processor 604 calls the instructions or programs in the memory 605 to execute the methods executed by the modules shown in the above-mentioned cell switching processing device and achieve the same technical effect. To avoid repetition, it will not be described here.

[0348] An embodiment of the present application also provides a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, the various processes of the above-mentioned cell switching processing method embodiment are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0349] The processor is the processor in the terminal described in the above embodiment. The readable storage medium includes a computer-readable storage medium, such as a computer read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk. In some examples, the readable storage medium may be a non-transitory readable storage medium.

[0350] An embodiment of the present application further provides a chip, which includes a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the various processes of the above-mentioned cell switching processing method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0351] It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

[0352] An embodiment of the present application further provides a computer program / program product, which is stored in a storage medium. The computer program / program product is executed by at least one processor to implement the various processes of the above-mentioned cell switching processing method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0353] An embodiment of the present application further provides a wireless communication system, including: a terminal and a network-side device, wherein the terminal can be used to execute the steps of the above-mentioned cell switching processing method, and the network-side device can be used to execute the steps of the above-mentioned cell switching processing method.

[0354] It should be noted that, in this article, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the opposite order according to the functions involved. For example, the described method may be performed in an order different from that described, and various steps may also be added, omitted or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0355] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of a computer software product plus a necessary general-purpose hardware platform, or of course, by hardware. The computer software product is stored in a storage medium (such as ROM, RAM, magnetic disk, optical disk, etc.) and includes a number of instructions for enabling a terminal or network-side device to execute the methods described in each embodiment of the present application.

[0356] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms of implementation methods without departing from the purpose of this application and the scope of protection of the claims. These implementation methods are all within the protection of this application.

Claims

1. A method for processing a cell handover, comprising: The terminal obtains at least one layer 1 or layer 2 triggered mobility LTM candidate cell configuration; When the terminal switches to the target cell, the terminal releases or retains at least part of the LTM candidate cell configurations in the at least one LTM candidate cell configuration according to the first rule; The first rule includes any one of the following: Whether the target cell meets the first condition; The indication information sent by the target cell.

2. The method according to claim 1, wherein: The first condition includes at least one of the following: The target cell and the source cell have the same first identifier, and the first identifier is used to determine whether to perform packet data convergence protocol PDCP reconstruction and key change during handover; The target cell and the source cell are in the same first list, and the first list is used to determine whether to perform PDCP reestablishment and key change during handover; The primary cell configuration or the primary cell group configuration of the target cell does not include a master key change indication, and the master key change indication is used to indicate that the terminal needs to change the master key during the process of switching the primary cell to the target cell; The primary and secondary cell configuration or the secondary cell group configuration of the target cell does not include a secondary key change indication, and the secondary key change indication is used to indicate that the terminal needs to change the secondary key during the process of switching the primary and secondary cells to the target cell.

3. The method according to claim 1 or 2, wherein: The first rule includes whether the target cell satisfies a first condition; The terminal releases or retains at least part of the at least one LTM candidate cell configuration according to the first rule, including: When the target cell satisfies the first condition, the terminal retains all LTM candidate cell configurations in the at least one LTM candidate cell configuration; or, When the target cell does not satisfy the first condition, the terminal releases all LTM candidate cell configurations in the at least one LTM candidate cell configuration; or, In a case where the target cell does not satisfy the first condition, the terminal retains the LTM candidate cell configuration that satisfies the second condition or the third condition among the at least one LTM candidate cell configuration, and releases the remaining LTM candidate cell configurations; The second condition includes at least one of the following: having the same first identifier as the target cell and being in the same first list as the target cell; the third condition includes at least one of the following: having a different first identifier from the source cell and being in a different first list from the source cell.

4. The method according to claim 1, wherein: The first rule includes the indication information; The terminal releases or retains at least part of the at least one LTM candidate cell configuration according to the first rule, including: The terminal releases all LTM candidate cell configurations in the at least one LTM candidate cell configuration when receiving the first indication information, wherein the first indication information is used to instruct the terminal to release all the LTM candidate cell configurations or, The terminal releases at least part of the at least one LTM candidate cell configuration according to the second indication information, where the second indication information is used to indicate the LTM candidate cell configuration to be released; or, The terminal retains at least part of the at least one LTM candidate cell configuration according to third indication information, where the third indication information is used to indicate the LTM candidate cell configuration that needs to be retained.

5. The method according to claim 4, wherein: The second indication information includes an identifier of the LTM candidate cell configuration to be released; or, The second indication information instructs the terminal to release the LTM candidate cell configuration that meets a fourth condition, where the fourth condition includes at least one of the following: the candidate cell and the target cell have different first identifiers, and the candidate cell and the target cell are in different first lists.

6. The method according to claim 4, wherein: The third indication information includes an identifier of the LTM candidate cell configuration that needs to be retained; or, The third indication information instructs the terminal to retain the LTM candidate cell configuration that meets a fifth condition, where the fifth condition includes at least one of the following: the candidate cell and the target cell have the same first identifier, and the candidate cell and the target cell are in the same first list.

7. The method according to any one of claims 1 to 6, wherein: The LTM candidate cell configuration includes at least one of the following: Layer 1 measurement configuration associated with the LTM candidate cell; The cell configuration applied when the terminal accesses the LTM candidate cell; The transmission configuration indicator TCI state configuration associated with the LTM candidate cell; The random access channel RACH configuration associated with the LTM candidate cell.

8. The method according to any one of claims 1 to 7, wherein: The method further comprises: The terminal determines the LTM candidate cell configuration of the target cell from the at least one LTM candidate cell configuration when receiving the LTM switching command or satisfying the first execution condition, and performs LTM switching to the target cell according to the LTM candidate cell configuration of the target cell; the LTM switching command includes an identifier of the target cell or the target cell configuration, and the first execution condition is an execution condition of the LTM switching; or, The terminal performs a layer 3 handover to the target cell when receiving a layer 3 handover command, wherein the layer 3 handover command includes an identifier of the target cell; or, The terminal performs conditional handover to the target cell when a second execution condition is met, where the second execution condition is an execution condition of conditional handover CHO.

9. A method for processing a cell handover, comprising: The target concentration unit CU sends indication information to the terminal when confirming that the terminal switches to the target cell; The indication information is used to release or retain at least part of the LTM candidate cell configuration in at least one layer 1 or layer 2 triggered mobility LTM candidate cell configuration.

10. The method according to claim 9, wherein: The indication information is used to indicate the LTM candidate cell configuration to be released; The indication information includes an identifier of the LTM candidate cell configuration to be released; or, the indication information instructs the terminal to release the LTM candidate cell configuration that meets a fourth condition, and the fourth condition includes at least one of the following: the candidate cell and the target cell have different first identifiers, and the candidate cell and the target cell are in different first lists; the first identifier or the first list is used to determine whether to perform packet data convergence protocol PDCP reconstruction and key change during switching.

11. The method according to claim 9, wherein: The indication information is used to indicate the LTM candidate cell configuration that needs to be retained; The indication information includes an identifier of the LTM candidate cell configuration that needs to be retained; or the indication information instructs the terminal to retain the LTM candidate cell configuration that meets the fifth condition, and the fifth condition includes at least one of the following: the candidate cell and the target cell have the same first identifier, and the candidate cell and the target cell are in the same first list; the first identifier or the first list is used to determine whether to perform PDCP reconstruction and key change during switching.

12. The method according to claim 10 or 11, wherein: The method further comprises: The target CU determines, according to the first information from the source CU, an identifier of the LTM candidate cell configuration to be released or to be retained; The first information includes at least one of the following: Configuration identification of each LTM candidate cell; The physical cell identifier PCI and frequency associated with the configuration identifier of each LTM candidate cell; The cell global identifier CGI associated with the configuration identifier of each LTM candidate cell; A first identifier associated with each LTM candidate cell; The identifier of the first list to which each LTM candidate cell belongs.

13. The method according to claim 9, wherein: The sending the indication information to the terminal includes: When the target cell does not satisfy the first condition, the target CU sends the indication information to the terminal; The first condition includes at least one of the following: The target cell and the source cell have the same first identifier, and the first identifier is used to determine whether to perform PDCP reestablishment and key change during handover; The target cell and the source cell are in the same first list, and the first list is used to determine whether to perform PDCP reestablishment and key change during handover; The primary cell configuration or the primary cell group configuration of the target cell does not include a master key change indication, and the master key change indication is used to indicate that the terminal needs to change the master key during the process of switching the primary cell to the target cell; The primary and secondary cell configuration or the secondary cell group configuration of the target cell does not include a secondary key change indication, and the secondary key change indication is used to indicate that the terminal needs to change the secondary key during the process of switching the primary and secondary cells to the target cell.

14. The method according to any one of claims 9 to 13, wherein: The sending the indication information to the terminal includes: The target CU sends the indication information to the terminal through a radio resource control RRC reconfiguration message or a media access control unit MAC CE signaling.

15. The method according to any one of claims 9 to 14, wherein: The LTM candidate cell configuration includes at least one of the following: Layer 1 measurement configuration associated with the LTM candidate cell; The cell configuration applied when the terminal accesses the LTM candidate cell; The transmission configuration indicator TCI state configuration associated with the LTM candidate cell; The random access channel RACH configuration associated with the LTM candidate cell.

16. A method for processing a cell handover, comprising: The source centralized unit CU sends first information to the first CU, where the first CU is all candidate CUs or target CUs, and the first information is used by the target CU to send indication information to the terminal, where the indication information is used to release or retain at least part of the LTM candidate cell configurations in the mobility LTM candidate cell configuration triggered by at least one layer 1 or layer 2; The first information includes at least one of the following: Configuration identification of each LTM candidate cell; The physical cell identifier PCI and frequency associated with the configuration identifier of each LTM candidate cell; The cell global identifier CGI associated with the configuration identifier of each LTM candidate cell; A first identifier associated with each LTM candidate cell; The identifier of the first list to which each LTM candidate cell belongs.

17. The method according to claim 16, wherein: The source CU sends first information to the first CU, including: Before initiating LTM switching, the source CU sends the first information to all the candidate CUs; or, When the LTM switch is initiated or the LTM switch is completed, the source CU sends the first information to the target CU.

18. The method according to claim 16 or 17, wherein: The indication information is used to indicate the LTM candidate cell configuration to be released; The indication information includes an identifier of the LTM candidate cell configuration to be released; or the indication information indicates that the terminal releases the LTM candidate cell configuration that satisfies the fourth condition, and the fourth condition includes at least one of the following: the candidate cell and the target cell have different first identifiers, and the candidate cell and the target cell are in different first lists; the first identifier or the first list is used to determine whether to perform group switching during switching Data Convergence Protocol PDCP re-establishment and key change.

19. The method according to claim 16 or 17, wherein: The indication information is used to indicate the LTM candidate cell configuration that needs to be retained; The indication information includes an identifier of the LTM candidate cell configuration that needs to be retained; or the indication information instructs the terminal to retain the LTM candidate cell configuration that meets the fifth condition, and the fifth condition includes at least one of the following: the candidate cell and the target cell have the same first identifier, and the candidate cell and the target cell are in the same first list; the first identifier or the first list is used to determine whether to perform PDCP reconstruction and key change during switching.

20. The method according to any one of claims 16 to 19, wherein: The method further comprises: The source CU sends the at least one LTM candidate cell configuration to the terminal; The LTM candidate cell configuration includes at least one of the following: Layer 1 measurement configuration associated with the LTM candidate cell; The cell configuration applied when the terminal accesses the LTM candidate cell; The transmission configuration indicator TCI state configuration associated with the LTM candidate cell; The random access channel RACH configuration associated with the LTM candidate cell.

21. A method for processing a cell handover, comprising: The target centralized unit CU sends second information to the target distributed unit DU when confirming that the terminal is switched to the target cell; The second information includes at least one of the following: The second indication information is used to instruct to stop sending the mobility LTM switching command triggered by layer 1 or layer 2 to the terminal; A list of identifiers of candidate target cells.

22. The method according to claim 21, wherein: The identifier list of the candidate target cells is used to indicate that the target DU is allowed to send an LTM switching command to the terminal, so that the terminal switches to the candidate target cells corresponding to the identifier list; or, The candidate target cell identification list is used to instruct the target DU to stop sending the LTM switching command to the terminal, so that the terminal switches to the candidate target cell corresponding to the identification list.

23. The method according to claim 21 or 22, wherein: After sending the second information to the target DU, the method further includes: The target CU sends third information to the target DU when completing the reconfiguration of the candidate cell key of the terminal; The third information includes at least one of the following: The third indication information is used to instruct the target DU to resume or restart sending an LTM switching command to the terminal; A second list of candidate target cells.

24. The method according to claim 23, wherein: The second list is used to indicate that the target DU is allowed to send an LTM switching command to the terminal, so that the terminal is switched to a candidate target cell corresponding to the second list; or, The second list is used to instruct the target DU to resume or restart sending an LTM switching command to the terminal, so that the terminal switches to the candidate target cell corresponding to the second list.

25. The method according to any one of claims 21 to 24, wherein: The method further comprises: The target CU determines, according to the first information from the source CU, a list of identifiers of the candidate target cells; The first information includes at least one of the following: Configuration identification of each LTM candidate cell; The physical cell identifier PCI and frequency associated with the configuration identifier of each LTM candidate cell; The cell global identifier CGI associated with the configuration identifier of each LTM candidate cell; A first identifier associated with each LTM candidate cell; The identifier of the first list to which each LTM candidate cell belongs.

26. A cell switching processing device, comprising: Acquisition module and processing module; The acquisition module is used to acquire at least one layer 1 or layer 2 triggered mobility LTM candidate cell configuration; The processing module is configured to release or retain at least part of the LTM candidate cell configurations in the at least one LTM candidate cell configuration according to a first rule when switching to a target cell; The first rule includes any one of the following: Whether the target cell meets the first condition; The indication information sent by the target cell.

27. A cell switching processing device, comprising: Send module; The sending module is used to send indication information to the terminal when confirming that the terminal is switched to the target cell; The indication information is used to release or retain at least part of the LTM candidate cell configuration in at least one layer 1 or layer 2 triggered mobility LTM candidate cell configuration.

28. A cell switching processing device, comprising: Send module; The sending module is used to send first information to a first CU, where the first CU is all candidate CUs or target CUs, and the first information is used by the target CU to send indication information to the terminal, where the indication information is used to release or retain at least part of the LTM candidate cell configurations in the mobility LTM candidate cell configuration triggered by at least one layer 1 or layer 2; The first information includes at least one of the following: Configuration identification of each LTM candidate cell; The physical cell identifier PCI and frequency associated with the configuration identifier of each LTM candidate cell; The cell global identifier CGI associated with the configuration identifier of each LTM candidate cell; A first identifier associated with each LTM candidate cell; The identifier of the first list to which each LTM candidate cell belongs.

29. A cell switching processing device, comprising: Send module; The sending module is used to send second information to the target distribution unit DU when confirming that the terminal is switched to the target cell; The second information includes at least one of the following: The second indication information is used to instruct to stop sending the mobility LTM switching command triggered by layer 1 or layer 2 to the terminal; A list of identifiers of candidate target cells.

30. A terminal comprising a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the cell handover processing method according to any one of claims 1 to 8 are implemented.

31. A network side device, comprising a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, it implements the steps of the cell switching processing method as described in any one of claims 9 to 15, or implements the steps of the cell switching processing method as described in any one of claims 16 to 20, or implements the steps of the cell switching processing method as described in any one of claims 21 to 25.

32. A readable storage medium storing a program or instruction, wherein the program or instruction, when executed by a processor, implements the steps of the cell switching processing method as described in any one of claims 1 to 8, or implements the steps of the cell switching processing method as described in any one of claims 9 to 15, or implements the steps of the cell switching processing method as described in any one of claims 16 to 20, or implements the steps of the cell switching processing method as described in any one of claims 21 to 25.

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