Cell switching method and device, storage medium and electronic device

Abstract

The embodiment of the invention provides a cell switching method and device, a storage medium and an electronic device, and the method comprises the steps that UE sends a physical layer measurement report to network equipment, so that the network equipment determines to initiate layer 1 or layer 2 triggered mobile LTM switching; the UE receives first signaling information sent by the network device, the first signaling information being used for instructing the UE to switch to a target cell, and the first signaling information comprising configuration indication information of the target cell; the first signaling information is a layer 1 or layer 2 signaling; and determining a random access mode in the target cell, and switching to the target cell according to the random access mode. By adopting the technical scheme, the problem that the service of the UE is interrupted due to the fact that the UE loses the connection with the original cell when the UE is subjected to LTM switching in the related technology is solved.

Description

Technical Field

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

[0002] The UE-to-Network relay (U2N Relay) technology in related technologies is a communication method in which a relay UE (Relay UE) provides relay communication for a remote UE (Remote UE), allowing the remote UE to access a radio access network device through the relay UE. The relay UE and the remote UE communicate via the PC5 interface. The wireless communication link between the relay UE and the remote UE is called a sidelink (SL). The relay UE and the network device communicate wirelessly via the Uu interface. The wireless communication link between the relay UE and the network device can be called a Uu link.

[0003] Terminal devices can implement L1 / L2 handover of the primary cell through layer L1 / L2 triggered mobility (LTM). Unlike existing cell handovers triggered based on layer 3 (L3, i.e., RRC layer), LTM may have low latency during handover (HO), where the UE may perform HO based only on L1 / L2 indications (e.g., MAC CE), where a secondary cell or even a non-serving cell from the candidate LTM set may be promoted to the new primary cell. When a UE undergoes LTM handover, the UE loses connection with the original cell, resulting in service interruption for the UE.

[0004] In the related art, when a UE undergoes LTM handover, the UE loses connection with the original cell, which causes service interruption of the UE. No effective solution has been proposed yet. Summary of the Invention

[0005] The embodiments of the present application provide a cell switching method, apparatus, storage medium, and electronic device to at least solve the problem that when a UE undergoes LTM switching, the UE loses connection with the original cell, resulting in service interruption of the UE.

[0006] According to one aspect of an embodiment of the present application, a cell switching method is provided, including: the UE sends a physical layer measurement report to a network device, so that the network device determines to initiate a mobile LTM switching triggered by layer 1 or layer 2; the UE receives first signaling information sent by the network device, wherein the first signaling information is used to instruct the UE to switch to a target cell, and the first signaling information includes configuration indication information of the target cell; the first signaling information is layer 1 or layer 2 signaling; determining a random access mode in the target cell, and switching to the target cell according to the random access mode.

[0007] In an exemplary embodiment, the method further includes: when the random access mode of the target cell is successfully terminated or uplink data is successfully transmitted, the UE determines that the mobile LTM handover is successful.

[0008] In an exemplary embodiment, before the UE receives the first signaling information sent by the network device, the method further includes: the UE measuring the timing advance information of the target cell and achieving uplink and downlink synchronization with the target cell.

[0009] In an exemplary embodiment, the method also includes: when the UE is a relay UE, after receiving the first signaling information sent by the network device where the source cell is located, sending a switching indication information to the remote UE according to the first signaling information to instruct the remote UE to switch to the target cell or determine whether to initiate relay UE reselection.

[0010] In an exemplary embodiment, the method further includes: determining a random access mode and a number of preamble repetition transmissions, wherein the random access mode includes at least one of the following: contention-based random access CBRA, contention-free random access CFRA, and random access-less RACH-less; the number of preamble repetition transmissions is notified to the UE by the network device; and switching to the target cell according to the random access mode.

[0011] In an exemplary embodiment, the method also includes: the quality threshold value corresponding to the number of repeated transmissions of the preamble is configured by the network device, and different numbers of repeated transmissions of the preamble correspond to different quality threshold values; when the beam quality measured by the UE is less than or equal to a preset threshold value, the number of repeated transmissions of the preamble corresponding to the quality threshold value of the beam quality is selected.

[0012] In an exemplary embodiment, the method further includes: the random access mode is determined based on at least one of: timing advance information, channel quality of the target cell; wherein, if the first signaling information contains the timing advance information, or the UE has obtained the timing advance information before the mobile LTM switching, the RACH-less mode is adopted; if the UE does not obtain the timing advance information, the CFRA mode is adopted, and when the CFRA mode is selected, if the channel quality of the target cell is lower than a specified threshold, the CBRA mode is adopted.

[0013] In an exemplary embodiment, the method further includes: for the RACH-less mode, the number of preamble repetition transmissions is not required; the random access CBRA mode is broadcast by the system to indicate the threshold values ​​corresponding to different numbers of preamble repetition transmissions; for the conflict-free random access CFRA mode, the number of preamble repetition transmissions corresponding to the conflict-free random access CFRA mode is indicated by the network device, and the conflict-free random access CFRA mode is allowed to fall back to the conflict-based random access CBRA mode, and the number of preamble repetition transmissions remains unchanged when falling back.

[0014] In an exemplary embodiment, the method further includes: the first signaling information also includes: a timing advance command TAC of the target cell; wherein, when the UE receives the first signaling information including the TAC, it is determined that the UE uses a RACH-less mode to switch to the target cell.

[0015] In an exemplary embodiment, the method further includes: when the network device configures the UE to measure the target cell TA and the UE has measured the target cell TA, switching to the target cell using a RACH-less mode.

[0016] In an exemplary embodiment, the method further includes: when the LTM switching, conditional switching CHO and conditional primary and secondary cell addition or change CPAC exist simultaneously, instructing the network device to perform the LTM switching or the CHO; wherein, when the UE performs the LTM switching, it is allowed to receive and instruct the RRC layer switching command sent by the network device.

[0017] According to another aspect of an embodiment of the present application, a cell switching method is also provided, which is applied to a network device, including: receiving a physical layer measurement report sent by a user equipment UE, and initiating a layer 1 or layer 2 triggered mobile LTM switching based on the physical layer measurement report; sending a first signaling message to the UE to instruct the UE to determine the random access mode in the target cell based on the random access resources indicated by the configuration indication information of the target cell included in the first signaling message, and switch to the target cell according to the random access mode, wherein the first signaling message is used to instruct the UE to switch to the target cell, and the first signaling message is layer 1 or layer 2 signaling.

[0018] In an exemplary embodiment, the method further includes: the first signaling information also includes: a timing advance command TAC of the target cell; wherein, when the UE receives the first signaling information including the TAC, it is determined that the UE uses a random access RACH-less mode to switch to the target cell.

[0019] According to another aspect of the embodiment of the present application, a cell switching device is also provided, which is applied to a user equipment UE, including: a first sending module, used to send a physical layer measurement report to a network device, so that the network device determines to initiate a mobile LTM switching triggered by layer 1 or layer 2; a first receiving module, used to receive first signaling information sent by the network device, wherein the first signaling information is used to instruct the UE to switch to the target cell, and the first signaling information includes configuration indication information of the target cell; the first signaling information is layer 1 or layer 2 signaling; a switching module, used to determine a random access mode in the target cell, and switch to the target cell according to the random access mode.

[0020] According to another aspect of the embodiment of the present application, a cell switching device is also provided, which is applied to a network device, including: a second receiving module, used to receive a physical layer measurement report sent by a user equipment UE, and initiate a layer 1 or layer 2 triggered mobile LTM switching based on the physical layer measurement report; a second sending module, used to send a first signaling message to the UE to instruct the UE to determine the random access mode in the target cell according to the random access resources indicated by the configuration indication information of the target cell included in the first signaling information, and switch to the target cell according to the random access mode, wherein the first signaling information is used to instruct the UE to switch to the target cell, and the first signaling information is layer 1 or layer 2 signaling.

[0021] According to another aspect of the embodiments of the present application, a computer-readable storage medium is provided, in which a computer program is stored. The computer program is configured to execute any of the cell switching methods described above when running.

[0022] According to another aspect of the embodiments of the present application, an electronic device is provided, characterized in that it includes a memory and a processor, the memory stores a computer program, and the processor is configured to execute any of the above-mentioned cell switching methods through the computer program.

[0023] According to another aspect of the embodiments of the present application, a computer program product is provided, including a computer program, characterized in that when the computer program is executed by a processor, the steps of any one of the above-mentioned cell switching methods are implemented.

[0024] Through this application, a physical layer measurement report is sent to a network device so that the network device initiates a mobile LTM handover triggered by layer 1 or layer 2, and then receives the first signaling information sent by the network device where the source cell is located, and then determines the random access mode in the target cell according to the configuration indication information of the target cell indicated by the network device included in the first signaling information, and switches to the target cell according to the random access mode. This solves the problem in the related art that when the UE undergoes LTM handover, the UE loses connection with the original cell, which causes the UE's service to be interrupted. Therefore, when the UE undergoes LTM handover, it can switch to the target cell according to the random access model corresponding to the first signaling information sent by the network device, avoiding the problem of UE service interruption. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The exemplary embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0026] Figure 1 This is a hardware structure block diagram of a UE in a cell switching method according to an embodiment of the present application;

[0027] Figure 2 is a flowchart of a cell switching method applied to a user equipment UE according to an embodiment of the present application;

[0028] Figure 3 is a flowchart of a cell switching method applied to a network device according to an embodiment of the present application;

[0029] Figure 4 is a schematic diagram of the architecture of a communication system according to an embodiment of the present application;

[0030] Figure 5 is an interactive schematic diagram of a cell switching method according to an embodiment of the present application;

[0031] Figure 6 5 is an interactive schematic diagram of a cell handover method corresponding to step S505 according to an embodiment of the present application;

[0032] Figure 7 5 is an interactive schematic diagram of a cell handover method corresponding to step S506 according to an embodiment of the present application;

[0033] Figure 8 is another flowchart of a cell switching method according to an embodiment of the present application;

[0034] Figure 9 is another flowchart of a cell switching method according to an embodiment of the present application;

[0035] Figure 10 is a structural block diagram of a cell switching apparatus applied to a user equipment UE according to an embodiment of the present application;

[0036] Figure 11 This is a structural block diagram of a cell switching device applied to a network device according to an embodiment of the present application. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0038] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in a sequence other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0039] The method embodiments provided in the embodiments of the present application can be executed in UE or network equipment. Taking running in UE as an example, Figure 1 FIG is a block diagram of the hardware structure of a UE in the cell switching method according to an embodiment of the present application. Figure 1 As shown, the UE may include one or more ( Figure 1Only one is shown in the figure) processor 202 (processor 202 may include but is not limited to a microprocessor (Microprocessor Unit, referred to as MPU) or a programmable logic device (Programmable logic device, referred to as PLD)) and a memory 204 for storing data. In an exemplary embodiment, the above-mentioned UE may also include a transmission device 206 and an input / output device 208 for communication functions. It will be understood by those skilled in the art that Figure 1 The structure shown is only for illustration and does not limit the structure of the above-mentioned computer terminal. For example, the computer terminal may also include Figure 1 More or fewer components than shown, or with Figure 1 Equivalent functions or comparisons shown Figure 1 Shown are different configurations with more functionality.

[0040] The memory 204 can be used to store computer programs, for example, software programs and modules of application software, such as the computer program corresponding to the cell handover method in the embodiment of the present application. The processor 202 executes various functional applications and data processing by running the computer program stored in the memory 204, that is, implementing the above-mentioned method. The memory 204 may include a high-speed random access memory and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 204 may further include a memory remotely located relative to the processor 202, and these remote memories may be connected to the computer terminal via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0041] Transmission device 206 is used to receive or transmit data via a network. A specific example of the aforementioned network may include a wireless network provided by a communications provider of a computer terminal. In one embodiment, transmission device 206 includes a network interface controller (NIC), which can be connected to other network devices via a base station to enable communication with the Internet. In another embodiment, transmission device 206 may be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0042] Figure 2 is a flow chart of a cell switching method applied to a user equipment UE according to an embodiment of the present application, such as Figure 2 As shown, the steps of the method include:

[0043] Step S202: The UE sends a physical layer measurement report to a network device, so that the network device determines to initiate a layer 1 or layer 2 triggered mobility LTM handover.

[0044] In step S204, the UE receives first signaling information sent by the network device, wherein the first signaling information is used to instruct the UE to switch to the target cell, and the first signaling information includes configuration indication information of the target cell; the first signaling information is layer 1 or layer 2 signaling.

[0045] Step S206: Determine a random access mode in the target cell, and switch to the target cell according to the random access mode.

[0046] Through this application, a physical layer measurement report is sent to a network device so that the network device initiates a mobile LTM handover triggered by layer 1 or layer 2, and then receives the first signaling information sent by the network device where the source cell is located, and then determines the random access mode in the target cell according to the configuration indication information of the target cell indicated by the network device included in the first signaling information, and switches to the target cell according to the random access mode. This solves the problem in the related art that when the UE undergoes LTM handover, the UE loses connection with the original cell, which causes the UE's service to be interrupted. Therefore, when the UE undergoes LTM handover, it can switch to the target cell according to the random access model corresponding to the first signaling information sent by the network device, avoiding the problem of UE service interruption.

[0047] Optionally, the network device instructs the UE whether to perform uplink and downlink synchronization with the candidate target cell in advance (before receiving the first signaling information). If so, for uplink synchronization, the UE selects the UE acquisition method of the candidate cell according to the network device indication information: network acquisition or UE measurement acquisition. Network acquisition means that the UE sends a preamble to the candidate cell, but does not wait to receive the RAR information. The candidate network device calculates the TA and indicates it to the UE. UE measurement of TA means that the UE measures the timing information of the source cell and obtains the TA of the candidate cell through the time difference with the candidate cell. For downlink synchronization, the UE proceeds according to the transmission configuration indication (TCI) status indicated by the network device. After receiving the first signaling, the UE can deactivate the TCI status not indicated in the first signaling information. For UEs that are undergoing LTM switching, they do not participate in measurement intervals or discontinuous reception DRX operations.

[0048] In an exemplary embodiment, the method further includes: when the random access mode of the target cell is successfully terminated or uplink data is successfully transmitted, the UE determines that the mobile LTM handover is successful.

[0049] In an exemplary embodiment, before the UE receives the first signaling information sent by the network device, the method further includes: the UE measuring the timing advance information of the target cell and achieving uplink and downlink synchronization with the target cell.

[0050] In an exemplary embodiment, the method also includes: when the UE is a relay UE, after receiving the first signaling information sent by the network device where the source cell is located, sending a switching indication information to the remote UE according to the first signaling information to instruct the remote UE to switch to the target cell or determine whether to initiate relay UE reselection.

[0051] In actual operation, when a relay UE initiates a random access process in a target cell, it may repeatedly transmit the random access preamble multiple times to increase the coverage of the random access preamble. If the resource quality of the target cell indicated in the LTM handover command deteriorates, the random access mode and the number of preamble repetitions need to be adjusted. In an exemplary embodiment, the adjustment can be performed in the following manner: determining the random access mode and the number of preamble repetitions, wherein the random access mode includes at least one of the following: contention-based random access (CBRA), contention-free random access (CFRA), and random access-less (RACH-less); notifying the UE of the number of preamble repetitions by the network device; and switching to the target cell based on the random access mode.

[0052] In an exemplary embodiment, the method also includes: the quality threshold value corresponding to the number of repeated transmissions of the preamble is configured by the network device, and different numbers of repeated transmissions of the preamble correspond to different quality threshold values; when the beam quality measured by the UE is less than or equal to a preset threshold value, the number of repeated transmissions of the preamble corresponding to the quality threshold value of the beam quality is selected.

[0053] In an exemplary embodiment, the method further includes: the random access mode is determined based on at least one of: timing advance information, channel quality of the target cell; wherein, if the first signaling information contains the timing advance information, or the UE has obtained the timing advance information before the mobile LTM switching, the RACH-less mode is adopted; if the UE does not obtain the timing advance information, the CFRA mode is adopted, and when the CFRA mode is selected, if the channel quality of the target cell is lower than a specified threshold, the CBRA mode is adopted.

[0054] In an exemplary embodiment, the method further includes: for the RACH-less mode, the number of preamble repetition transmissions is not required; the random access CBRA mode is broadcast by the system to indicate the threshold values ​​corresponding to different numbers of preamble repetition transmissions; for the conflict-free random access CFRA mode, the number of preamble repetition transmissions corresponding to the conflict-free random access CFRA mode is indicated by the network device, and the conflict-free random access CFRA mode is allowed to fall back to the conflict-based random access CBRA mode, and the number of preamble repetition transmissions remains unchanged when falling back.

[0055] In an exemplary embodiment, the method further includes: the first signaling information also includes: a timing advance command TAC of the target cell; wherein, when the UE receives the first signaling information including the TAC, it is determined that the UE uses a RACH-less mode to switch to the target cell.

[0056] In an exemplary embodiment, the method further includes: when the network device configures the UE to measure the target cell TA and the UE has measured the target cell TA, switching to the target cell using a RACH-less mode.

[0057] In an exemplary embodiment, the method further includes: when the LTM switching, conditional switching CHO and conditional primary and secondary cell addition or change CPAC exist simultaneously, instructing the network device to perform the LTM switching or the CHO; wherein, when the UE performs the LTM switching, it is allowed to receive and instruct the RRC layer switching command sent by the network device.

[0058] Figure 3 : is a flowchart of a cell switching method applied to a network device according to an embodiment of the present application. Figure 3 As shown, the steps of the method include:

[0059] Step S302: Receive a physical layer measurement report sent by a user equipment UE, and initiate a layer 1 or layer 2 triggered mobility LTM handover according to the physical layer measurement report.

[0060] Step S304: Send first signaling information to the UE to instruct the UE to determine the random access mode in the target cell according to the random access resources indicated by the configuration indication information of the target cell included in the first signaling information, and switch to the target cell according to the random access mode, wherein the first signaling information is used to instruct the UE to switch to the target cell, and the first signaling information is layer 1 or layer 2 signaling.

[0061] Through this application, a physical layer measurement report sent by a user equipment UE is received, and a mobile LTM handover triggered by layer 1 or layer 2 is initiated based on the physical layer measurement report, and then a first signaling message is sent to the UE to instruct the UE to determine the random access mode in the target cell based on the random access resources indicated by the configuration indication information of the target cell included in the first signaling message, and switch to the target cell according to the random access mode. This solves the problem in the related art that when the UE undergoes LTM handover, the UE loses connection with the original cell, which causes the UE's service to be interrupted. Furthermore, when the UE undergoes LTM handover, it can switch to the target cell according to the random access model corresponding to the first signaling message sent by the network device, avoiding the problem of UE service interruption.

[0062] Optionally, the network device instructs the UE whether to perform uplink and downlink synchronization with the candidate target cell in advance (before receiving the first signaling information). If so, for uplink synchronization, the UE selects the UE acquisition method of the candidate cell according to the network device indication information: network acquisition or UE measurement acquisition. Network acquisition means that the UE sends a preamble to the candidate cell, but does not wait to receive the RAR information. The candidate network device calculates the TA and indicates it to the UE. UE measurement of TA means that the UE measures the timing information of the source cell and obtains the TA of the candidate cell through the time difference with the candidate cell. For downlink synchronization, the UE proceeds according to the transmission configuration indication (TCI) status indicated by the network device. After receiving the first signaling, the UE can deactivate the TCI status not indicated in the first signaling information. For UEs that are undergoing LTM switching, they do not participate in measurement intervals or discontinuous reception DRX operations.

[0063] In an exemplary embodiment, the method further includes: the first signaling information also includes: a timing advance command TAC of the target cell; wherein, when the UE receives the first signaling information including the TAC, it is determined that the UE uses a random access RACH-less mode to switch to the target cell.

[0064] In order to better understand the above-mentioned cell switching process, the optional embodiment of the present application provides the following technical solutions to explain the above-mentioned cell switching process.

[0065] An optional embodiment of the present application provides a cell switching method, user equipment UE, network equipment and communication system to provide a way to indicate cell switching and determine a random access mode in a target cell.

[0066] In an optional embodiment, the embodiment of the present application provides a cell handover method, applied to a user equipment UE, the method including:

[0067] During an LTM handover process, receiving first signaling information sent by a network device in a source cell, the first signaling information being used to instruct the UE to hand over to a target cell; wherein the first signaling information includes target cell configuration indication information indicated by the network device; and if the UE is a relay UE, sending handover indication information to a remote UE;

[0068] The UE determines a random access mode and the number of preamble repetitions, wherein the random access mode includes at least: contention-based random access (CBRA), contention-free random access (CFRA) or no random access (RACH-less) process, and initiates a random access process to the target cell according to the determined random access mode. The number of preamble repetitions is notified to the UE by the network device configuration, and the network device configures the quality threshold of the preamble repetition number. Different repetition numbers correspond to different threshold values, and a higher repetition number corresponds to a lower quality threshold value. When the UE measures the beam quality (L1) and it is not higher than the preset threshold value, the corresponding number of preamble repetitions is selected. For the RACH-less process, since the preamble does not need to be sent, there is no preamble repetition number; the threshold values ​​of different repetition numbers are indicated by the system broadcast in CBRA, and the network device in CRFA explicitly indicates the repetition number. CRFA can fall back to CBRA, and the number of preamble repetitions remains unchanged when falling back.

[0069] In another optional embodiment, the embodiment of the present application also provides a cell switching method, which is applied to a network device, and the method includes: during the LTM switching process, sending a first signaling message to the user equipment UE, wherein the first signaling message instructs the UE to switch to the target cell, wherein the first signaling message includes the configuration indication information of the target cell. The first signaling message may also include a target cell timing advance command (TAC, Timing Advance Command). If TAC is included, the UE initiates RACH-less in the target cell. If the network device configures the UE to measure the target cell TA, and the UE has measured the target cell TA, the RACH-less process is initiated in the target cell. The first signaling message may include access resource indication information of CFRA, such as the preamble index, the SSB index of the target cell, the random access timing RO, etc.

[0070] Among them, LTM switching and conditional switching CHO, conditional primary and secondary cell addition or change CPAC can exist at the same time, and the UE can instruct the network device to use LTM or CHO; when the UE performs LTM switching, it is allowed to receive and instruct the RRC layer switching command sent by the network device.

[0071] The embodiments of the present application also provide a cell switching method, user equipment UE, network equipment and communication system.

[0072] In a first aspect, an embodiment of the present application provides a cell handover method, the method comprising:

[0073] During the LTM switching process, first signaling information sent by the network device is received, where the first signaling information is used to instruct the UE to switch to the target cell; wherein the first signaling information includes the random access resources of the target cell indicated by the network device; and a random access process is initiated to the target cell based on the random access resources in the first signaling information.

[0074] In conjunction with some embodiments of the first aspect, in some embodiments, initiating a random access procedure to the target cell according to the first signaling information includes at least one of the following:

[0075] If the UE is a relay UE, handover indication information is sent to the remote UE associated with the relay UE. The UE determines whether it is a relay UE based on network equipment indication or upper layer information. The UE is in RRC-connected mode, that is, it is connected to the source cell. The remote UE determines whether to initiate relay UE reselection or switch to the target cell based on the received handover indication information.

[0076] If the UE is a relay UE, handover indication information is sent to the associated remote UE.

[0077] The UE performs layer 1 (L1) measurement on the access beam of the target cell, such as SSB / CSI-RS measurement in the beam, and determines the random access mode and the number of preamble repetitions based on the measurement results and the network device indication information;

[0078] In the above embodiment, the random access mode is used to initiate random access to the target cell at the random access opportunity RO corresponding to the determined SSB;

[0079] In conjunction with some embodiments of the first aspect, in some embodiments, determining the random access mode and the number of preamble repetitions based on the measurement results and the network device indication information includes:

[0080] The first signaling information includes target cell configuration indication information.

[0081] The measurement result is the RSRP of the beam. Assuming that the network device has enabled the preamble repetition function, if the measurement result is not lower than the specified threshold value A, CFRA is adopted, and random access is performed using the number of preamble repetitions specified by the network device; if the measurement result is lower than the threshold value A, CBRA is adopted, and the number of preamble repetitions indicated by the network device remains unchanged;

[0082] If the network device presets a threshold B and the measurement result is lower than the specified threshold value B, CFRA is used and the number of preamble repetitions corresponding to threshold 2 is selected. Alternatively, if the measurement result is not lower than any specified threshold value B, the lowest number of preamble repetitions is used according to the network device indication information, or preamble repetition is not used (that is, the preamble is not repeatedly sent before receiving the random access response RAR), or the number of preamble repetitions corresponding to the current resource. Different preamble repetition numbers correspond to different random access resources.

[0083] In conjunction with some embodiments of the first aspect, in some embodiments, the first signaling indication information includes CFRA resource indication information, which may indicate an access timing RO of the SSB / CSI-RS corresponding to the access beam, i.e., the UE sends a preamble at the indicated RO. If the preamble is repeatedly sent, multiple ROs are required. The RO group may be determined first, and then the corresponding RO index in the RO is indicated.

[0084] In combination with some embodiments of the first aspect, in some embodiments, the L1 measurement of the access beam of the target cell includes: if the L1 measurement result of the access beam resource is less than or equal to a preset threshold value, selecting other beam resources whose L1 quality exceeds the preset threshold value, and initiating random access to the target cell at the RO corresponding to the selected beam resource.

[0085] In a second aspect, an embodiment of the present application provides a cell handover method, the method comprising:

[0086] During the LTM switching process, the network device sends first signaling information, where the first signaling information is used to instruct the UE to switch to the target cell; wherein the first signaling information includes candidate target cell configuration indication information indicated by the network device; and instructs the UE to initiate a random access process to the target cell.

[0087] In conjunction with some embodiments of the second aspect, in some embodiments, the first signaling information includes an indication of a random access resource and a timing advance command for a candidate cell, the random access resource includes a CFRA resource. If the timing advance command information is included in the first signaling information, the UE uses a RACH-less procedure in the target cell.

[0088] In an eleventh aspect, an embodiment of the present application provides a chip or a chip system. The chip or chip system includes:

[0089] The processing circuit is configured to execute the method described according to the optional implementation of the first aspect and the second aspect above.

[0090] It is understandable that the above-mentioned user equipment UE, network equipment, communication system, storage medium, program product, computer program, chip or chip system are all used to perform the method proposed in the embodiment of the present application. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects of the corresponding method and will not be repeated here.

[0091] The embodiments of the present application provide a cell switching method, a user equipment (UE), a network device, and a communication system. In some embodiments, the cell switching method, random access method, cell reselection method, and other terms are interchangeable, and the information processing system, communication system, and other terms are interchangeable.

[0092] The embodiments of the present application are not exhaustive, but are merely illustrative of some embodiments and are not intended to be a specific limitation on the scope of protection of the present application. In the absence of contradiction, each step in a certain embodiment can be implemented as an independent embodiment, and the steps can be arbitrarily combined. For example, a solution after removing some steps in a certain embodiment can also be implemented as an independent embodiment, and the order of the steps in a certain embodiment can be arbitrarily exchanged. In addition, the optional implementations in a certain embodiment can be arbitrarily combined; in addition, the embodiments can be arbitrarily combined. For example, some or all of the steps in different embodiments can be arbitrarily combined, and a certain embodiment can be arbitrarily combined with the optional implementations of other embodiments.

[0093] In each embodiment of the present application, unless otherwise specified or there is any logical conflict, the terms and / or descriptions between the embodiments are consistent and can be referenced by each other. The technical features in different embodiments can be combined to form a new embodiment based on their inherent logical relationships.

[0094] The present application also provides a communication system. Figure 4 As shown, Figure 4 : is a schematic diagram of the architecture of a communication system according to an embodiment of the present application. Figure 4 As shown, the communication system 400 includes a user equipment UE 401 and a network device 402 .

[0095] In an optional embodiment, UE 401 includes, for example, at least one of a mobile phone, a wearable device, an Internet of Things device, a car with communication capabilities, a smart car, a tablet computer, a computer with wireless transceiver capabilities, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal device in industrial control, a wireless terminal device in self-driving, a wireless terminal device in remote medical surgery, a wireless terminal device in a smart grid, a wireless terminal device in transportation safety, a wireless terminal device in a smart city, and a wireless terminal device in a smart home, but is not limited thereto.

[0096] When UE 401 asks the relay UE, the remote UE associated with the relay UE is also included. The remote UE is connected to the network device 402 through the relay UE. The remote UE may also have a link directly connected to the network device 402, such as a Uu link. The link between the remote UE and the relay UE is a side link (SL). The relay UE provides the remote UE with functions and resources for connecting to the network device 402, and transmits user plane data and control plane signaling between the remote UE and the network device 402.

[0097] In an optional embodiment, the network device 402 may include at least one of an access network device and a core network device.

[0098] In an optional embodiment, the core network device may be a device including one or more network elements, or may be multiple devices or device groups, each including all or part of the one or more network elements. The network element may be virtual or physical. The core network may include, for example, at least one of an evolved packet core (EPC), a 5G core network (5GCN), and a next generation core (NGC).

[0099] It can be understood that the communication system described in the embodiment of the present application is for the purpose of more clearly illustrating the technical solution of the embodiment of the present application, and does not constitute a limitation on the technical solution proposed in the embodiment of the present application. Ordinary technicians in this field can know that with the evolution of the system architecture and the emergence of new business scenarios, the technical solution proposed in the embodiment of the present application is also applicable to similar technical problems.

[0100] The following embodiments of the present application can be applied to Figure 4 The communication system 400, or a portion thereof, is shown but is not limited thereto. Figure 4 The various entities shown are examples, and the communication system may include Figure 4 All or part of the subject, and may also include Figure 4 The number and form of other subjects are arbitrary, each subject can be physical or virtual, the connection relationship between the subjects is illustrative, the subjects can be connected or disconnected, and the connection can be in any way, which can be direct or indirect, wired or wireless.

[0101] Figure 5 FIG. 1 is an interactive diagram of a cell switching method according to an embodiment of the present application. Figure 5 As shown, the above method includes:

[0102] Step 501 : The network device 402 sends candidate cell configuration information to the user equipment UE 401 .

[0103] In order to communicate with a network device, a user equipment needs to establish a wireless connection with a cell controlled by the network device so as to reside in the cell controlled by the network device. The cell with which the user equipment has established a wireless connection is called the serving cell of the user equipment.

[0104] In mobile communication systems, due to changes in user equipment mobility and / or cell channel conditions, a user equipment may switch serving cells. The serving cell where the user equipment originally resides is generally referred to as the source cell, and the cell where the user equipment newly resides is generally referred to as the target cell. This means that the user equipment switches from the source cell to the target cell. The process of switching a user equipment from a source cell to a target cell is called a cell handover.

[0105] UE 401 performs layer 3 (L3) measurement and reports the measurement result according to the configuration information of network device 402. Network device 402 determines that UE 401 can perform layer L1 / 2 triggered mobile LTM handover according to the capability of UE 401 and the measurement report, and sends configuration information of LTM candidate cells to UE 101. The LTM configuration information is sent through an RRC reconfiguration message. The LTE configuration information includes one or more of the following: candidate cell identifier, beam SSB / CSI-RS configuration, UE-based candidate cell TA measurement indication, TCI configuration, reference signal SSB / CSI-RS threshold configuration, etc.

[0106] UE 401 receives and stores the LTM candidate cell configuration information.

[0107] In step 502, UE 401 performs uplink and downlink synchronization with the candidate cell.

[0108] If the LTM candidate cell configuration information received by UE 401 includes SSB configuration and TCI status information, downlink synchronization is achieved with the candidate cell. If TA acquisition based on UE TA measurement indication or PDCCH indication is included, the TA of the candidate cell is acquired and uplink synchronization is achieved using the TA.

[0109] It should be noted that step 502 is an optional step. If step 502 is present, the UE performs a RACH-less process in the target cell, that is, uplink data can be directly sent in the target cell without the need for a random access process. If step 502 is not present, the UE 401 performs a random access process in the target cell.

[0110] In step 503 , the UE 401 performs L1 measurement and sends an L1 measurement report to the network device 402 .

[0111] L1 measurements are physical layer (L1) measurements, also known as beam measurements. Based on the measurement reference information in the received LTM configuration information, the user performs L1 measurements on each candidate cell, including the serving cell, and reports the measurement results to the serving cell for use in determining whether a handover is necessary and to which target cell. As long as UE 401 stores a valid candidate cell configuration, L1 measurements can be performed and reported.

[0112] Step 504: The network device 402 sends first signaling information to the UE 401, where the first signaling information is used to trigger the UE to switch to a target cell.

[0113] The network device 402 decides to perform LTM cell handover based on the L1 measurement report, and sends first signaling information through a MAC CE.

[0114] The first signaling information includes a target cell configuration indication indicated by the network device, CRFA access resources, TCI status indication, timing advance command TAC, etc.

[0115] The network device 402 can send a first signaling message to the UE 401 in the serving cell (i.e., the source cell). The first signaling message is used to trigger the UE to switch to the target cell, and the first signaling message carries the target cell configuration indication indicated by the network device. The target cell configuration indication can be used by the UE 401 to initiate random access to the target cell.

[0116] In step 505, UE 401 performs L1 measurement in the target cell and selects a random access mode according to the measurement result and network device configuration information.

[0117] If UE 401 does not have valid target cell TA information, it initiates a random access procedure in the target cell; otherwise, it initiates a RACH-less procedure in the target cell.

[0118] The L1 measurement is the RSRP of the beam. Assuming that the network device has enabled the preamble repetition function, if the measurement result is not lower than the specified threshold value A, CFRA is adopted, and random access is performed using the number of preamble repetitions specified by the network device; if the measurement result is lower than the threshold value A, CBRA is adopted, and the number of preamble repetitions indicated by the network device remains unchanged;

[0119] If the network device presets a threshold B and the measurement result is lower than the specified threshold value B, CFRA is used and the number of preamble repetitions corresponding to threshold 2 is selected. Alternatively, if the measurement result is not lower than any specified threshold value B, the lowest number of preamble repetitions is used according to the network device indication information, or preamble repetition is not used (that is, the preamble is not repeatedly sent before receiving the random access response RAR), or the number of preamble repetitions corresponding to the current resource. Different preamble repetition numbers correspond to different random access resources.

[0120] In an optional embodiment, the first signaling indication information includes CFRA resource indication information, which may indicate an access timing RO of the SSB / CSI-RS corresponding to the access beam, that is, the UE sends a preamble at the indicated RO. If the preamble is repeatedly sent, multiple ROs are required. The RO group may be determined first, and then the corresponding RO index in the RO is indicated.

[0121] In an optional embodiment, performing L1 measurement on the target cell access beam includes:

[0122] If the L1 measurement result of the access beam resource is less than or equal to the preset threshold C, other beam resources whose L1 quality exceeds the preset threshold C are selected, and random access is initiated to the target cell at the RO corresponding to the selected beam resource.

[0123] If UE 401 determines that it is a relay UE, it sends a handover information indication to the associated remote UE.

[0124] Step 506: UE 401 accesses the target cell according to the selected random access mode.

[0125] Step 507: The UE completes the LTM process.

[0126] If UE 401 performs the RA procedure, the terminal considers that the LTM cell switching execution has been successfully completed when the random access procedure is successfully completed. For LTM without rach, when UE 401 determines that network device 402 has successfully received its first uplink data, UE 401 considers that the LTM cell switching execution has been successfully completed.

[0127] In an alternative embodiment, if Figure 6 As shown, step 505 also includes the following contents:

[0128] Step 601: UE receives first signaling information;

[0129] In step 602, UE 101 determines that it is a relay UE, and then performs one of steps 603 or 604. UE 401 determines that it is a relay UE according to the indication information of the network device 402 or the upper layer indication information.

[0130] Step 603: UE 401 sends handover indication information to the remote UE.

[0131] UE 401 sends a handover indication message to the remote UE via the sidelink. Further, UE 401 sends the target cell configuration information to the remote UE. The remote UE does not disconnect the sidelink connection with UE 101 and accesses the target cell together with UE 401. The remote UE may also disconnect the sidelink connection with UE 101 and select a new relay UE to access the network device 402.

[0132] Step 604: The network device 402 sends handover indication information to the remote UE.

[0133] If a Uu direct link exists between the remote UE and the network device 402, the network device 402 may send a handover indication message to the UE 401, and the remote UE may select a new relay UE, or access the target cell together with the UE 401, or simply disconnect the sidelink connection with the UE 401.

[0134] In an alternative embodiment, if Figure 7 As shown, step 506 includes methods 1 to 3.

[0135] Specifically, in step 701, after UE 401 determines the random access mode, it may perform one of steps 702 to 704.

[0136] In the first method (step 702), RACH-less access is determined. UE 401 sends uplink data in the target cell according to the scheduling resources configured by network device 402. If it is determined that network device 402 has successfully received the uplink data, the LTM handover process ends.

[0137] In the second method (step 703), the CFRA mode is determined to be adopted. The UE 401 further determines the access resources and preamble repetition count of the target cell, initiates the CFRA process in the target cell, and when the random access response RAR message sent by the network device 402 is received, the LTM handover process ends.

[0138] Method three (step 704) determines to adopt the CBRA mode, UE101 selects the access timing and preamble, as well as the number of preamble repetitions, and initiates random access in the target cell; UE401 performs L1 measurement on the access beam. If the measurement result is lower than the preset threshold, UE401 selects other beams for access until it receives the RAR message sent by the network device, and then determines that the LTM process is completed.

[0139] In an optional embodiment, the names of information, etc. are not limited to the names described in the embodiment, and terms such as "information", "message", "signal", "signaling", "report", "configuration", "indication", "instruction", "command", "channel", "parameter", "domain", "field", "symbol", "codepoint", "bit", "data", "program", and "chip" can be used interchangeably.

[0140] In some embodiments, terms such as "certain", "preset", "preset", "setting", "indicated", "a certain", "any", and "first" can be interchangeable. "Specific A", "preset A", "preset A", "setting A", "indicated A", "a certain A", "any A", and "first A" can be interpreted as A pre-specified in a protocol, etc., or as A obtained through setting, configuration, or indication, etc., or as specific A, a certain A, any A, or first A, etc., but not limited to this.

[0141] In some embodiments, the determination or judgment can be performed by a value represented by 1 bit (0 or 1), or by a true or false value (Boolean value) represented by true or false, or by comparison of numerical values ​​(for example, comparison with a predetermined value), but is not limited thereto.

[0142] In some embodiments, "not expecting to receive" can be interpreted as not receiving on time domain resources and / or frequency domain resources, or as not performing subsequent processing on the data after receiving it; "not expecting to send" can be interpreted as not sending, or as sending but not expecting the recipient to respond to the content sent.

[0143] The cell switching method involved in the embodiments of the present application may include at least one of the aforementioned steps and embodiments.

[0144] Figure 8 FIG. 1 is another flow chart of a cell switching method according to an embodiment of the present application. Figure 8 As shown, the above method can be applied to user equipment UE 401, and the above method includes:

[0145] Step 801: receiving first signaling information sent by a network device;

[0146] The first signaling information is used to trigger the UE to switch to the target cell; wherein the first signaling information includes an indication of the candidate cell configuration information indicated by the network device;

[0147] Step 802: Determine the random access mode. If there is no valid target cell TA, proceed to step 803; otherwise, proceed to step 806.

[0148] The valid target cell TA includes: the TAC in the first signaling information, or the TA measured by the UE.

[0149] Step 803 , measure the L1 beam quality of the target cell. If the L1 measurement result is higher than the threshold value A preset by the network device 402 , go to step 804 ; otherwise, go to step 805 .

[0150] The threshold value A is used to fall back to CBRA, that is, when the beam quality of the target cell is lower than the threshold value A, CFRA chooses to fall back to CBRA.

[0151] Step 804, performing CFRA according to the instruction information of the network device 402;

[0152] UE 401 initiates CFRA according to the resources and preamble repetition times indicated by network device 402 .

[0153] Step 805: Select resources for CBRA.

[0154] UE 401 falls back to CBRA, selects a new beam to access the target cell, and the number of preamble repetitions remains unchanged according to the instruction of network device 402.

[0155] Step 806: Connect to the target cell using RACH-less;

[0156] UE 101 directly sends uplink data on the PUSCH in the target cell according to the received scheduling resources.

[0157] Step 807: LTM ends.

[0158] Using the candidate cell configuration information provided by the network device 402, the LTM process may be performed multiple times in different target cells.

[0159] The cell switching method involved in the embodiments of the present application may include at least one of the aforementioned steps and embodiments.

[0160] Figure 9 FIG. 1 is another flow chart of a cell switching method according to an embodiment of the present application. Figure 9 As shown, the method is applied to a network device, and the method includes:

[0161] Step 901: Send first signaling information to user equipment UE;

[0162] The first signaling information is used to trigger the UE to switch to the target cell using LTM. The first signaling information includes configuration information indication of the target cell.

[0163] Optionally, the first signaling information includes TAC, target cell random access resources, such as access preamble index, access timing RO, and SSB index.

[0164] Optionally, the network device sends LTM switching indication information to the remote UE.

[0165] Step 902: Receive the leading edge or uplink data sent by the UE.

[0166] If the UE adopts the RACH-less mode, the network device receives the uplink data sent by the UE; if the UE adopts the CBRA / CRFA mode, the network device receives the preamble sent by the UE.

[0167] Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus the necessary general hardware platform, and of course it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a readable storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for enabling a terminal device (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods of each embodiment of the present application.

[0168] This embodiment also provides a cell switching device for implementing the above-mentioned embodiments and preferred implementations. Details already described will not be repeated. As used below, the term "module" may refer to a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation using hardware, or a combination of software and hardware, is also possible and contemplated.

[0169] Figure 10 FIG is a structural block diagram of a cell switching device applied to a user equipment UE according to an embodiment of the present application. Figure 10 As shown, the cell switching device includes:

[0170] A first sending module 1002 is configured to send a physical layer measurement report to a network device so that the network device determines to initiate a layer 1 or layer 2 triggered mobility LTM handover;

[0171] A first receiving module 1004 is configured to receive first signaling information sent by the network device, wherein the first signaling information is used to instruct the UE to switch to a target cell, the first signaling information including configuration indication information of the target cell; and the first signaling information is layer 1 or layer 2 signaling;

[0172] The switching module 1006 is configured to determine a random access mode in the target cell and switch to the target cell according to the random access mode.

[0173] Through this application, a physical layer measurement report is sent to a network device so that the network device initiates a mobile LTM handover triggered by layer 1 or layer 2, and then receives the first signaling information sent by the network device where the source cell is located, and then determines the random access mode in the target cell according to the configuration indication information of the target cell indicated by the network device included in the first signaling information, and switches to the target cell according to the random access mode. This solves the problem in the related art that when the UE undergoes LTM handover, the UE loses connection with the original cell, which causes the UE's service to be interrupted. Therefore, when the UE undergoes LTM handover, it can switch to the target cell according to the random access model corresponding to the first signaling information sent by the network device, avoiding the problem of UE service interruption.

[0174] Optionally, the network device instructs the UE whether to perform uplink and downlink synchronization with the candidate target cell in advance (before receiving the first signaling information). If so, for uplink synchronization, the UE selects the UE acquisition method of the candidate cell according to the network device indication information: network acquisition or UE measurement acquisition. Network acquisition means that the UE sends a preamble to the candidate cell, but does not wait to receive the RAR information. The candidate network device calculates the TA and indicates it to the UE. UE measurement of TA means that the UE measures the timing information of the source cell and obtains the TA of the candidate cell through the time difference with the candidate cell. For downlink synchronization, the UE proceeds according to the transmission configuration indication (TCI) status indicated by the network device. After receiving the first signaling, the UE can deactivate the TCI status not indicated in the first signaling information. For UEs that are undergoing LTM switching, they do not participate in measurement intervals or discontinuous reception DRX operations.

[0175] In an exemplary embodiment, the apparatus further includes: a determining module configured to determine that the mobile LTM handover is successful if the random access mode of the target cell is successfully terminated or uplink data is successfully sent.

[0176] In an exemplary embodiment, the determining module is further configured to measure the timing advance information of the target cell and achieve uplink and downlink synchronization with the target cell before the UE receives the first signaling information sent by the network device.

[0177] In an exemplary embodiment, the first receiving module is further used to, when the UE is a relay UE, after receiving the first signaling information sent by the network device of the source cell, send a switching indication information to the remote UE according to the first signaling information to instruct the remote UE to switch to the target cell or determine whether to initiate relay UE reselection.

[0178] In actual operation, when a relay UE initiates a random access process in a target cell, it may repeatedly send the random access preamble multiple times to increase the coverage of the random access preamble. If the resource quality of the target cell indicated in the LTM handover command decreases, the random access mode and the number of preamble repetitions need to be adjusted. In an exemplary embodiment, the determination module is configured to determine the random access mode and the number of preamble repetitions, wherein the random access mode includes at least one of the following: contention-based random access (CBRA), contention-free random access (CFRA), and random access-less (RACH-less); the number of preamble repetitions is notified to the UE by the network device; and handover to the target cell is performed based on the random access mode.

[0179] In an exemplary embodiment, the quality threshold value corresponding to the number of repeated preamble transmissions is configured by the network device, and different numbers of repeated preamble transmissions correspond to different quality threshold values; when the beam quality measured by the UE is less than or equal to a preset threshold value, the number of repeated preamble transmissions corresponding to the quality threshold value of the beam quality is selected.

[0180] In an exemplary embodiment, the random access mode is determined based on at least one of the following: timing advance information, channel quality of the target cell; wherein, if the first signaling information contains the timing advance information, or the UE has obtained the timing advance information before the mobile LTM switching, the RACH-less mode is adopted; if the UE does not obtain the timing advance information, the CFRA mode is adopted. When the CFRA mode is selected, if the channel quality of the target cell is lower than a specified threshold, the CBRA mode is adopted.

[0181] In an exemplary embodiment, for the RACH-less mode, the number of preamble repetition transmissions is not required; the random access CBRA mode is broadcast by the system to indicate the threshold values ​​corresponding to different numbers of preamble repetition transmissions; for the conflict-free random access CFRA mode, the number of preamble repetition transmissions corresponding to the conflict-free random access CFRA mode is indicated by the network device, and the conflict-free random access CFRA mode is allowed to fall back to the conflict-based random access CBRA mode, and the number of preamble repetition transmissions remains unchanged during the fallback.

[0182] In an exemplary embodiment, the first signaling information further includes: a timing advance command TAC of the target cell; wherein the determination module is further configured to determine that the UE switches to the target cell in RACH-less mode when the UE receives the first signaling information including the TAC.

[0183] In an exemplary embodiment, the switching module is further configured to, when the network device configures the UE to measure the target cell TA and the UE has measured the target cell TA, switch to the target cell using a RACH-less mode.

[0184] In an exemplary embodiment, when the LTM switching, conditional switching CHO and conditional primary and secondary cell addition or change CPAC exist simultaneously, the network device is instructed to perform the LTM switching or the CHO; wherein, when the UE performs the LTM switching, it is allowed to receive and instruct the RRC layer switching command sent by the network device.

[0185] Figure 11 1 is a structural block diagram of a cell switching device applied to a network device according to an embodiment of the present application. Figure 11 As shown, the cell switching device includes:

[0186] The second receiving module 1102 is configured to receive a physical layer measurement report sent by a user equipment UE, and initiate a layer 1 or layer 2 triggered mobility LTM handover according to the physical layer measurement report;

[0187] The second sending module 1104 is used to send first signaling information to the UE to instruct the UE to determine the random access mode in the target cell according to the random access resources indicated by the configuration indication information of the target cell included in the first signaling information, and switch to the target cell according to the random access mode, wherein the first signaling information is used to instruct the UE to switch to the target cell, and the first signaling information is layer 1 or layer 2 signaling.

[0188] Through this application, a physical layer measurement report sent by a user equipment UE is received, and a mobile LTM handover triggered by layer 1 or layer 2 is initiated based on the physical layer measurement report, and then a first signaling message is sent to the UE to instruct the UE to determine the random access mode in the target cell based on the random access resources indicated by the configuration indication information of the target cell included in the first signaling message, and switch to the target cell according to the random access mode. This solves the problem in the related art that when the UE undergoes LTM handover, the UE loses connection with the original cell, which causes the UE's service to be interrupted. Furthermore, when the UE undergoes LTM handover, it can switch to the target cell according to the random access model corresponding to the first signaling message sent by the network device, avoiding the problem of UE service interruption.

[0189] Optionally, the network device instructs the UE whether to perform uplink and downlink synchronization with the candidate target cell in advance (before receiving the first signaling information). If so, for uplink synchronization, the UE selects the UE acquisition method of the candidate cell according to the network device indication information: network acquisition or UE measurement acquisition. Network acquisition means that the UE sends a preamble to the candidate cell, but does not wait to receive the RAR information. The candidate network device calculates the TA and indicates it to the UE. UE measurement of TA means that the UE measures the timing information of the source cell and obtains the TA of the candidate cell through the time difference with the candidate cell. For downlink synchronization, the UE proceeds according to the transmission configuration indication (TCI) status indicated by the network device. After receiving the first signaling, the UE can deactivate the TCI status not indicated in the first signaling information. For UEs that are undergoing LTM switching, they do not participate in measurement intervals or discontinuous reception DRX operations.

[0190] The first signaling information further includes: a timing advance command TAC of the target cell; wherein, when the UE receives the first signaling information including the TAC, it is determined that the UE adopts a random access-free RACH-less mode to switch to the target cell.

[0191] It should be understood that the division of the various units or modules in the above device is merely a division of logical functions. In actual implementation, they may be fully or partially integrated into a physical entity, or they may be physically separated. In addition, the units or modules in the device may be implemented in the form of a processor calling software: for example, the device includes a processor, the processor is connected to a memory, and the memory stores instructions. The processor calls the instructions stored in the memory to implement any of the above methods or implement the functions of the various units or modules of the above device, wherein the processor is, for example, a general-purpose processor, such as a central processing unit (CPU) or a microprocessor, and the memory is a memory within the device or a memory outside the device. Alternatively, the units or modules in the device can be implemented in the form of hardware circuits, and the functions of some or all of the units or modules can be realized by designing the hardware circuits. The above-mentioned hardware circuits can be understood as one or more processors; for example, in one implementation, the above-mentioned hardware circuit is an application-specific integrated circuit (ASIC), which realizes the functions of some or all of the above units or modules by designing the logical relationship of the components in the circuit; for example, in another implementation, the above-mentioned hardware circuit can be realized by a programmable logic device (PLD). Taking a field programmable gate array (FPGA) as an example, it can include a large number of logic gate circuits, and the connection relationship between the logic gate circuits is configured by configuring the configuration file, thereby realizing the functions of some or all of the above units or modules. All units or modules of the above devices can be realized in the form of software called by the processor, or in the form of hardware circuits, or in part by the form of software called by the processor, and the rest by hardware circuits.

[0192] In an embodiment of the present application, the processor is a circuit with signal processing capability. In one implementation, the processor can be a circuit with instruction reading and running capability, such as a central processing unit (CPU), a microprocessor, a graphics processing unit (GPU) (which can be understood as a microprocessor), or a digital signal processor (DSP). In another implementation, the processor can implement certain functions through the logical relationship of the hardware circuit. The logical relationship of the above-mentioned hardware circuit is fixed or reconfigurable, such as a hardware circuit implemented by a processor as an application-specific integrated circuit (ASIC) or a programmable logic device (PLD), such as an FPGA. In a reconfigurable hardware circuit, the processor loads a configuration document to implement the process of hardware circuit configuration, which can be understood as the process of the processor loading instructions to implement the functions of some or all of the above units or modules. In addition, it can also be a hardware circuit designed for artificial intelligence, which can be understood as an ASIC, such as a neural network processing unit (NPU), a tensor processing unit (TPU), a deep learning processing unit (DPU), etc.

[0193] For specific examples in this embodiment, reference may be made to the examples described in the above embodiments and exemplary implementation modes, and this embodiment will not be described in detail here.

[0194] An embodiment of the present application further provides a storage medium, which includes a stored program, wherein the program executes any of the above methods when it is run.

[0195] Optionally, in this embodiment, the storage medium may be configured to store program codes for executing the following steps:

[0196] S1: The UE sends a physical layer measurement report to a network device, so that the network device determines to initiate a layer 1 or layer 2 triggered mobility LTM handover.

[0197] S2, the UE receives first signaling information sent by the network device, wherein the first signaling information is used to instruct the UE to switch to a target cell, and the first signaling information includes configuration indication information of the target cell; the first signaling information is layer 1 or layer 2 signaling.

[0198] S3: Determine a random access mode in the target cell, and switch to the target cell according to the random access mode.

[0199] An embodiment of the present application further provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to execute the steps in any one of the above method embodiments.

[0200] Optionally, in this embodiment, the processor may be configured to execute the following steps through a computer program:

[0201] S1: The UE sends a physical layer measurement report to a network device, so that the network device determines to initiate a layer 1 or layer 2 triggered mobility LTM handover.

[0202] S2, the UE receives first signaling information sent by the network device, wherein the first signaling information is used to instruct the UE to switch to a target cell, and the first signaling information includes configuration indication information of the target cell; the first signaling information is layer 1 or layer 2 signaling.

[0203] S3: Determine a random access mode in the target cell, and switch to the target cell according to the random access mode.

[0204] In an exemplary embodiment, the electronic device may further include a transmission device and an input / output device, wherein the transmission device is connected to the processor, and the input / output device is connected to the processor.

[0205] Optionally, in this embodiment, the electronic device may also be configured to execute steps S1, S2 and S3 via a computer program.

[0206] For specific examples in this embodiment, reference may be made to the examples described in the above embodiments and exemplary implementation modes, and this embodiment will not be described in detail here.

[0207] An embodiment of the present application further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the steps in any one of the above method embodiments are implemented.

[0208] An embodiment of the present application further provides another computer program product, comprising a non-volatile computer-readable storage medium, wherein the non-volatile computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of any of the above method embodiments are implemented.

[0209] An embodiment of the present application also provides a computer program, which includes computer instructions stored in a computer-readable storage medium; a processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device performs the steps of any of the above method embodiments.

[0210] Obviously, those skilled in the art should understand that the modules or steps of the present application described above can be implemented using a general-purpose computing device, they can be concentrated on a single computing device, or distributed across a network composed of multiple computing devices, they can be implemented using program code executable by the computing device, and thus, they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be performed in a different order than herein, or they can be fabricated into separate integrated circuit modules, or multiple modules or steps can be fabricated into a single integrated circuit module for implementation. Thus, the present application is not limited to any specific combination of hardware and software.

[0211] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, improvements, etc. made within the principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A cell handover method, applied to a user equipment UE, characterized in that: include: The UE sends a physical layer measurement report to a network device, so that the network device determines to initiate a layer 1 or layer 2 triggered mobility LTM handover; The UE receives first signaling information sent by the network device, wherein the first signaling information is used to instruct the UE to switch to a target cell, the first signaling information includes configuration indication information of the target cell; and the first signaling information is layer 1 or layer 2 signaling; Determine a random access mode in the target cell, and switch to the target cell according to the random access mode.

2. The cell switching method according to claim 1, wherein: The method further comprises: In a case where the random access mode of the target cell is successfully terminated or uplink data is successfully sent, the UE determines that the mobile LTM handover is successful.

3. The cell switching method according to claim 1, wherein: Before the UE receives the first signaling information sent by the network device, the method further includes: The UE measures the timing advance information of the target cell and achieves uplink and downlink synchronization with the target cell.

4. The cell switching method according to claim 1, wherein: The method further comprises: In the case where the UE is a relay UE, after receiving the first signaling information sent by the network device where the source cell is located, a switching indication information is sent to the remote UE according to the first signaling information to instruct the remote UE to switch to the target cell or determine whether to initiate relay UE reselection.

5. The cell switching method according to claim 1, wherein: The method further comprises: Determining a random access mode and a number of preamble repetition transmissions, wherein the random access mode includes at least one of the following: contention-based random access (CBRA), contention-free random access (CFRA), and random access-less (RACH-less); and notifying the UE of the number of preamble repetition transmissions by the network device; Switching to the target cell according to the random access mode.

6. The cell switching method according to claim 5, characterized in that: The method further comprises: The quality threshold value corresponding to the number of repeated transmissions of the preamble is configured by the network device, and different numbers of repeated transmissions of the preamble correspond to different quality threshold values; when the beam quality measured by the UE is less than or equal to the preset threshold value, the number of repeated transmissions of the preamble corresponding to the quality threshold value of the beam quality is selected.

7. The cell switching method according to any one of claims 1 to 6, characterized in that: The method further comprises: The random access mode is determined according to at least one of the following: timing advance information, channel quality of the target cell; wherein, if the first signaling information contains the timing advance information, or the UE has obtained the timing advance information before the mobile LTM switching, the RACH-less mode is adopted; if the UE does not obtain the timing advance information, the CFRA mode is adopted. When the CFRA mode is selected, if the channel quality of the target cell is lower than a specified threshold, the CBRA mode is adopted.

8. The cell switching method according to claim 7, characterized in that: The method further comprises: For the RACH-less mode, the number of preamble repetitions is not required; The random access CBRA mode is broadcast by the system to indicate the threshold values ​​corresponding to different preamble repetition times; For the conflict-free random access CFRA mode, the network device indicates the number of preamble repetitions corresponding to the conflict-free random access CFRA mode, allowing the conflict-free random access CFRA mode to fall back to the conflict-based random access CBRA mode, and the number of preamble repetitions remains unchanged when falling back.

9. The cell switching method according to claim 1, wherein: The method further comprises: The first signaling information further includes: a timing advance command TAC of the target cell; wherein, when the UE receives the first signaling information including the TAC, it is determined that the UE adopts a RACH-less mode to switch to the target cell.

10. The cell switching method according to claim 1, wherein: The method further comprises: When the network device configures the UE to measure the target cell TA and the UE has measured the target cell TA, the RACH-less mode is adopted to switch to the target cell.

11. The cell switching method according to claim 1, wherein: The method further includes: instructing the network device to perform the LTM handover or the CHO when the LTM handover, the conditional handover CHO, and the conditional primary and secondary cell addition or change CPAC exist simultaneously; When the UE performs the LTM switching, it is allowed to receive and instruct the RRC layer switching command sent by the network device.

12. A cell switching method, applied to a network device, characterized in that: include: receiving a physical layer measurement report sent by a user equipment UE, and initiating a layer 1 or layer 2 triggered mobility LTM handover according to the physical layer measurement report; Sending first signaling information to the UE to instruct the UE to determine the random access mode in the target cell according to the random access resources indicated by the configuration indication information of the target cell included in the first signaling information, and switching to the target cell according to the random access mode, wherein the first signaling information is used to instruct the UE to switch to the target cell, and the first signaling information is layer 1 or layer 2 signaling.

13. The cell switching method according to claim 12, wherein: The method further comprises: The first signaling information further includes: a timing advance command TAC of the target cell; wherein, when the UE receives the first signaling information including the TAC, it is determined that the UE adopts a random access-free RACH-less mode to switch to the target cell.

14. A cell switching device, applied to a user equipment UE, characterized in that: include: A first sending module is configured to send a physical layer measurement report to a network device so that the network device determines to initiate a layer 1 or layer 2 triggered mobility LTM handover; A first receiving module is configured to receive first signaling information sent by the network device, wherein the first signaling information is used to instruct the UE to switch to a target cell, the first signaling information includes configuration indication information of the target cell; and the first signaling information is layer 1 or layer 2 signaling; The switching module is configured to determine a random access mode in the target cell and switch to the target cell according to the random access mode.

15. A cell switching device, applied to a network device, characterized in that: include: A second receiving module is configured to receive a physical layer measurement report sent by a user equipment UE, and initiate a layer 1 or layer 2 triggered mobile LTM handover according to the physical layer measurement report; A second sending module is used to send first signaling information to the UE to instruct the UE to determine the random access mode in the target cell according to the random access resources indicated by the configuration indication information of the target cell included in the first signaling information, and switch to the target cell according to the random access mode, wherein the first signaling information is used to instruct the UE to switch to the target cell, and the first signaling information is layer 1 or layer 2 signaling.

16. A computer-readable storage medium, characterized in that The storage medium stores a computer program, wherein the computer program is configured to execute the method according to any one of claims 1 to 11 or any one of claims 12 to 13 when run.

17. An electronic device, characterized in that: The method comprises a memory and a processor, wherein the memory stores a computer program, and the processor is configured to execute the method according to any one of claims 1 to 11 or the method according to any one of claims 12 to 13 through the computer program.

18. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method described in any one of claims 1 to 11 or the steps of the method described in any one of claims 12 to 13 are implemented.

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