Method executed by user equipment, and user equipment

Abstract

Provided are a method executed by a user equipment, and a user equipment. The method comprises: on the basis of a conditional layer 1 / layer 2 triggered mobility (CLTM) configuration, executing CLTM condition evaluation on the basis of a CLTM execution condition comprised in the CLTM configuration; and on the basis of whether the CLTM execution condition is a condition associated with layer 1 or a condition associated with layer 3, causing an RRC layer or a MAC layer in the user equipment to stop the CLTM condition evaluation.

Description

Methods executed by user equipment and user equipment Technical Field

[0001] This disclosure relates to the field of wireless communication technology, and more specifically, to a method performed by a user equipment and a user equipment. Background Technology

[0002] Mobility performance in wireless networks is a crucial metric, and in next-generation (NR) wireless networks, mobility technologies are continuously being improved and enhanced. At the 3GPP RAN plenary meeting in March 2024, a research project on the fourth phase of NR mobility enhancements in version 19 was approved (see 3GPP non-patent document RP-240299). This research project focuses on enhancing air interface mobility in Radio Resource Connection (RRC) connection states, where mobility refers to changes in the primary cell (PCell) or primary secondary cell group cell (PSCell) in the NR system. This topic investigates enhancements to Layer 1 / Layer 2 triggered mobility (LTM), primarily considering the following aspects:

[0003] • Develop support for LTM between sites (inter-CU), especially for scenarios where LTM between primary base stations is not configured with dual connectivity;

[0004] • Research on measurement-related enhancements to support LTM objectives, primarily including support for time-triggered Layer 1 measurement reporting and measurements of Channel State Information-Reference Signals (CSI-RS) for LTM procedures.

[0005] • Develop support for Conditional LTM (CLTM).

[0006] This disclosure aims to address the condition assessment problem in the condition-based LTM process in NR networks, and further, to address how the UE manages or maintains the condition assessment of LTM in a system configured with condition-based LTM. Summary of the Invention

[0007] The main objective of this disclosure is to provide a method and a user equipment (UE) executed by a UE to enable the UE to effectively manage the condition evaluation process related to CLTM candidate cells in a network configured with CLTM, avoid energy consumption caused by unnecessary condition evaluation processes and avoid triggering unnecessary CLTM execution processes, thereby better realizing the CLTM process.

[0008] According to a first aspect of this disclosure, a method performed by a user equipment is provided, comprising: performing a CLTM condition evaluation based on a condition-based layer 1 / layer 2 triggered mobility CLTM configuration received from a base station, and performing a CLTM condition evaluation according to CLTM execution conditions included in the CLTM configuration; and stopping the CLTM condition evaluation by an RRC layer or a MAC layer in the user equipment depending on whether the CLTM execution conditions are layer 1 or layer 3 associated conditions.

[0009] Optionally, performing CLTM condition evaluation may include starting CLTM condition evaluation at any of the following times: when the CLTM configuration is received; when the CLTM configuration stored in the user equipment includes at least one CLTM candidate configuration RRC reconfiguration message and the corresponding CLTM execution condition; or after receiving the CLTM configuration, the user equipment receives a time advance command corresponding to the CLTM candidate configuration after performing early uplink synchronization.

[0010] Optionally, depending on whether the CLTM execution condition is associated with Layer 1 or Layer 3, stopping the CLTM condition evaluation by the RRC layer or MAC in the user equipment may include: if the CLTM execution condition is associated with Layer 3, stopping the CLTM condition evaluation by the RRC layer when at least one of the following conditions is met: the RRC layer initiates an MCG failure information flow; the RRC layer initiates an SCG failure information flow; the RRC layer receives a first indication from the MAC layer indicating that the CLTM execution condition of at least one CLTM candidate has been met; if the CLTM execution condition is associated with Layer 1, stopping the CLTM condition evaluation by the MAC layer when at least one of the following conditions is met: the MAC entity of the user equipment is about to execute or is executing a MAC entity reset; the MAC layer receives a second indication from the RRC layer indicating to stop the CLTM condition evaluation; the MAC layer determines that the LTM cell change has been successfully completed; the MAC layer determines that the LTM cell change has started.

[0011] Optionally, the method may further include at least one of the following: when the RRC layer performs synchronization reconfiguration, it instructs the MAC layer to perform a MAC entity reset for the corresponding cell group; when the RRC layer initiates the initialization operation of the MCG failure information process, it instructs the MAC layer to perform a MAC entity reset for the corresponding cell group; when the RRC layer initiates the initialization operation of the SCG failure information process, it instructs the MAC layer to perform a MAC entity reset for the corresponding cell group; and triggers a MAC entity reset in response to SCG deactivation.

[0012] Optionally, the second indication information may be sent from the RRC layer to the MAC layer in at least one of the following situations: the RRC layer initiates a synchronization reconfiguration process; the RRC layer initiates an MCG failure information process; or the RRC layer initiates an SCG failure information process.

[0013] Optionally, the synchronous reconfiguration process initiated by the RRC layer can be a process for MCG or SCG.

[0014] Optionally, the second indication information can be used to indicate the cessation of CLTM condition evaluation associated with a specific CLTM candidate.

[0015] Optionally, the first indication information may include: indication information for indicating that at least one LTM cell change process has been triggered, or indication information for indicating that the CLTM execution conditions of a CLTM candidate have been met.

[0016] According to another aspect of the present invention, a user equipment is also provided, comprising: a processor; and a memory storing instructions, wherein the instructions, when executed by the processor, perform the method as described above.

[0017] According to the present invention, CLTM condition evaluation can be performed appropriately, and CLTM condition evaluation can be stopped appropriately. Attached Figure Description

[0018] The above and other features of this disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, wherein:

[0019] Figure 1 is a schematic flowchart illustrating the cell switch process based on the LTM mechanism.

[0020] Figure 2 is a schematic flowchart illustrating a method executed by a user equipment in one embodiment.

[0021] Figure 3 is a schematic flowchart illustrating another implementation of a method performed by a user device.

[0022] Figure 4 shows a block diagram of a user equipment according to an embodiment of the present disclosure. Detailed Implementation

[0023] Other aspects, advantages, and key features of this disclosure will become apparent to those skilled in the art from the following detailed description of exemplary embodiments of the disclosure taken in conjunction with the accompanying drawings.

[0024] In this disclosure, the terms “comprising” and “containing” and their derivatives are meant to include rather than limit; the term “or” is inclusive and may be equivalent to “and” or “and / or”.

[0025] In this specification, the various embodiments described below to illustrate the principles of this disclosure are merely illustrative and should not be construed as limiting the scope of the disclosure in any way. The following description, with reference to the accompanying drawings, is intended to aid in a comprehensive understanding of exemplary embodiments of this disclosure as defined by the claims and their equivalents. The following description includes various specific details to aid understanding, but these details should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this disclosure. Furthermore, for clarity and brevity, descriptions of well-known functions and structures have been omitted. Moreover, throughout the drawings, the same reference numerals are used for similar functions and operations.

[0026] The following description uses an NR mobile communication system as an example application environment to illustrate several implementations according to this disclosure. However, it should be noted that this disclosure is not limited to the following implementations, but is applicable to many other wireless communication systems.

[0027] The base station in this disclosure can be any type of base station, including Node B, enhanced base station eNB, 5G communication system base station gNB; or micro base station, pico base station, macro base station, home base station, etc.; the network side generally refers to the base station. The cell can also be a cell under any of the above-mentioned types of base stations. Unless otherwise specified, cell, beam, and transmission point (TRP) can be interchanged, and the base station can also be the central unit (gNB-Central Unit, gNB-CU) or distributed unit (gNB-Distributed Unit, gNB-DU) that makes up the base station. Different embodiments can also be combined, for example, the same variables / parameters / terms in different embodiments can be interpreted in the same way. Cancel, release, delete, clear, and clear can be replaced. Execute, use, and apply can be replaced. Configure and reconfigure can be replaced. Monitor and detect can be replaced. Initiate and trigger can be replaced. If..., if..., and under... circumstances can be replaced, or can be replaced with When the UE determines... In this disclosure, information elements and fields are interchangeable and are used to refer to a configuration contained in an RRC message or Layer 2 signaling.

[0028] The following section will first explain some existing mechanisms involved in this disclosure. It is worth noting that some names in the following description are merely illustrative and not restrictive, and may be used in other ways.

[0029] LTM mechanism

[0030] Traditional handover is triggered by a Layer 3 handover command (i.e., an RRC reconfiguration message containing synchronization reconfiguration information elements). To reduce data interruptions during mobility, the 3GPP working group introduced the LTM (Layer 1 / Layer 2 Triggered Mobility) mechanism. LTM can be used for serving cell changes within a Master Cell Group (MCG), such as changes to the Primary Cell (PCell), and also for serving cell changes within a Secondary Cell Group (SCG). Cell changes using the LTM mechanism are called cell switches to distinguish them from traditional handover. Figure 1 is a schematic flowchart illustrating the LTM-based cell switch process. As shown in Figure 1, the network side sends the LTM candidate cell configuration to the UE in advance via RRC signaling (such as an RRC reconfiguration message). After receiving the configuration, the UE saves the received LTM candidate cell configuration. The candidate cell configuration includes one or more RRC configurations corresponding to candidate cells (such as RRC reconfiguration messages containing synchronization reconfiguration information elements). The network side determines the final target cell based on the Layer 1 measurement results reported by the UE and triggers the cell switch procedure via MAC signaling (such as LTM Cell switch Command MAC CE). The MAC signaling used to trigger the cell switch procedure includes at least indication information of the target candidate cell configuration (such as the corresponding target candidate (configuration) identifier or index value), and may also include TAC, random access preamble index, downlink beam indication, etc. The UE triggers the cell switch procedure, starts timer T304, and applies the previously received LTM candidate configuration to perform the change process to the target cell. If timer T304 times out, the UE considers the LTM cell switch procedure to have failed. In version 18, the LTM configuration is contained in the LTM-Config information element in the RRC message. The LTM-Config information element contains an LTM candidate cell list (ltm-CandidateToAddModList information element), and each item in this list corresponds to the configuration of an LTM candidate cell (LTM-Candidate information element). An LTM candidate cell configuration includes at least one LTM candidate identifier (ltm-CandidateId information element), and may also include the physical cell identifier (ltm-CandidatePCI information element) and LTM candidate configuration (ltm-CandidateConfig information element), etc.The LTM candidate configuration field contains an RRC reconfiguration message for configuring an LTM candidate configuration, which is generated by the target candidate cell and is applied when the UE performs a cell switch to the target candidate cell.

[0031] Conditional LTM (CLTM):

[0032] One of the goals of the mobility enhancement agenda in version 19 is to introduce a condition-based LTM mechanism.

[0033] Conditional LTM can be divided into three phases: CLTM configuration, CLTM condition evaluation, and CLTM execution. In the CLTM configuration phase, when the network configures the UE with RRC configurations for one or more target candidate cells (including at least the corresponding RRC reconfiguration messages), each (or at least some) of these target candidate cells is associated with an execution condition configuration. The execution condition configuration can be associated with one or more measurement events (e.g., by configuring measurement identifiers). In the CLTM condition evaluation phase, the UE monitors the link quality of one or more CLTM candidate cells based on the associated measurement events. When the UE determines that all the execution conditions configured for one or more candidate cells are met, the UE determines a target cell and enters the CLTM execution phase, i.e., it automatically executes the cell switch procedure for that target cell and applies the RRC configuration of that target candidate cell. Therefore, Conditional LTM is a cell switching process where the network controls the UE's decision-making, abbreviated as Conditional LTM (CLTM). The execution conditions of CLTM can be configured based on Layer 1 measurement configurations or Layer 3 measurement configurations. When the execution conditions of a CLTM candidate are based on Layer 1 measurements, it is called a Layer 1 CLTM candidate (cell), and the corresponding LTM execution is called Layer 1 CLTM (execution). When the execution conditions of a CLTM candidate are based on Layer 3 measurements, it is called a Layer 3 CLTM candidate (cell), and the corresponding LTM execution is called Layer 3 CLTM (execution). For Layer 1 CLTM candidates, the condition evaluation operation is performed by the Media Access Control (MAC) layer, while for Layer 3 CLTM candidates, the condition evaluation operation is performed by the RRC layer.

[0034] Fast MCG link recovery mechanism:

[0035] In the fast MCG link recovery mechanism, when the UE's MCG experiences a radio link failure (RLF) or the UE fails to perform synchronization reconfiguration (i.e., the MCG timer T304 times out) such as a handover failure (HOF), if the UE has timer T316 configured (i.e., fast MCG link recovery is enabled) and the SCG link is available (i.e., not in the PSCell addition / change process (i.e., the T304 corresponding to the PSCell is not running), and the SCG transmission is not suspended and the SCG is not in a deactivated state), then neither the MCG (transmission) nor the SCG (transmission) is in a suspended (or interrupted) state or timer T316 is running. In this case, the UE initiates the MCG failure information flow, starts timer T316, and sends an MCG failure information (MCGFailureInformation) message containing the MCG link failure information report to the main base station through the SCG path (such as split SRB1 or SRB3), instead of directly triggering the RRC connection re-establishment process. In the MCG failure information flow, the UE will suspend the transmission of the MCG path, such as suspending the transmission of the MCG side corresponding to all SRBs and DRBs except SRB0, and resetting the MAC entity corresponding to the MCG. During the execution of timer T316, it will wait for a response from the network side (RRC reconfiguration message or RRC release message). The primary base station receiving the MCG failure information RRC message can send an RRC reconfiguration message containing synchronization reconfiguration information elements to the UE to trigger a handover to a new cell, or send an RRC release message to release the UE's RRC connection. After receiving the aforementioned RRC reconfiguration message or RRC release message, the UE stops T316 and performs the corresponding operation according to the received response message (RRC reconfiguration message or RRC release message). If the received message is an RRC reconfiguration message containing synchronization reconfiguration information elements, the UE performs a handover to the target cell; if the received message is an RRC release message, the UE releases the RRC connection and leaves the RRC connection state. If T316 times out, the UE initiates an RRC re-establishment process. In this disclosure, the MCG failure information process / mechanism, the fast MCG recovery process / mechanism, and the fast MCG link recovery process / mechanism are equivalent.

[0036] SCG Failure Information Process

[0037] In the current NR system, SCG failure information reporting is achieved through the SCG failure information procedure. When one or more of the following conditions are met, if neither the MCG nor the SCG transmission is suspended, the UE will initiate the SCG failure information procedure to report the SCG failure to the network side: detecting an SCG RLF, detecting beam failure of the PSCell while the SCG is deactivated, SCG synchronization reconfiguration failure, SCG configuration failure, and receiving an integrity check failure indication associated with SRB3 from the underlying layer. During the SCG failure process, the UE typically suspends the SCG transmission, resets the SCG MAC entity, stops the running timer T304, and sends an RRC message containing SCGFailureInformation to the network side via the MCG link. Based on the content of the SCGFailureInformation, the MCG can send an RRC message containing the SCG synchronization reconfiguration to the UE, triggering a change in the PSCell and restoring the SCG link; or it can send an RRC message containing an indication to release the SCG link to release the SCG. In version R18, the information in SCGFailureInformation may include: failure type, measurement results corresponding to the measurement configuration associated with SCG, measurement results corresponding to the measurement configuration associated with MCG, location information, failedPSCell identifier (failedPSCellId), previousPSCell identifier (previousPSCellId), etc.

[0038] In current 3GPP discussions, there is no consensus on the condition assessment for CLTM, such as when to start and stop CLTM-related condition assessments for CLTM-configured UEs, and how to start or stop these assessments. This differs from LTM in Release 18, where the network side triggers the LTM process and the UE does not need to assess the relevant conditions. Therefore, in Release 19 networks that support CLTM, how to maintain the corresponding CLTM condition assessments on the UE becomes one of the issues addressed in this disclosure.

[0039] This disclosure proposes a solution to at least a portion of the CLTM condition evaluation in the CLTM scenario described above, and specific implementation methods are given below.

[0040] The present invention will now be described in its entirety with reference to FIG2.

[0041] Figure 2 is a schematic flowchart illustrating a method executed by a user equipment in one embodiment.

[0042] In S202, the user equipment performs a CLTM condition evaluation based on the condition-based Layer 1 / Layer 2 triggered mobility CLTM configuration received from the base station, according to the CLTM execution conditions included in the CLTM configuration.

[0043] In S204, the user equipment stops CLTM condition evaluation by the RRC layer or MAC layer in the user equipment, depending on whether the CLTM execution condition is associated with layer 1 or layer 3.

[0044] The following provides a detailed description of specific examples and embodiments related to this invention. Furthermore, as described above, the examples and embodiments described in this disclosure are illustrative examples provided for easy understanding of the invention and are not intended to limit the invention. In the following embodiments, the order of the steps is merely illustrative and not strictly limited; the implementation steps can also be combined and implemented without limitation.

[0045] Figure 3 is a schematic flowchart illustrating some implementation steps or implementation methods of the condition evaluation method in the CLTM scenario on the UE. As shown in Figure 3, this implementation includes any one or more of the following steps (unless otherwise specified, the order of the steps is not limited).

[0046] Optionally, step 301: The UE receives the CLTM configuration from the base station.

[0047] Optionally, the CLTM configuration refers to the CLTM configuration in the RRC message received by the UE from the serving cell (e.g., indicated by the conditionalLTM-Config information element). The CLTM configuration contains a list of CLTM candidates, which includes the configurations of one or more CLTM candidates. Each CLTM candidate configuration contains at least one CLTM candidate identifier, and may also contain one or more of the following: CLTM candidate physical cell identifier (PCI), CLTM candidate configuration RRC reconfiguration message, etc. Each CLTM candidate configuration is also associated with one or more corresponding execution condition configurations. Optionally, the execution condition configuration is distinct from each CLTM candidate cell. Optionally, the execution condition configuration is common to all CLTM candidate cells. In this disclosure, CLTM candidate configuration and CLTM candidate cell configuration, CLTM candidate cell, and CLTM candidate are interchangeable. CLTM candidate configuration identifier and CLTM candidate identifier are interchangeable. Optionally, the RRC configuration of the CLTM target candidate cell is an RRC reconfiguration message contained in a CLTM candidate configuration. Optionally, the execution condition can also be called a measurement event.

[0048] Optionally, step 302: The UE performs a CLTM condition assessment.

[0049] Optionally, when the received CLTM configuration or the CLTM configuration saved / applied by the UE contains at least one CLTM candidate configuration and the corresponding execution conditions, the UE begins to perform CLTM condition evaluation.

[0050] Optionally, the UE or its MAC layer may begin CLTM condition evaluation at a later point in time (e.g., under certain circumstances) after receiving the CLTM configuration. For example, the UE or its MAC layer may begin CLTM condition evaluation after receiving a Timing Advance Command (TAC) MAC control element corresponding to a CLTM candidate configuration, following early uplink synchronization. Alternatively, the UE or its MAC layer may begin CLTM condition evaluation after receiving an indication command from the network side. Optionally, for Layer 3-based CLTM candidates, the RRC layer may begin CLTM condition evaluation after receiving an indication from the MAC layer, such as an indication from the MAC layer that a Timing Advance Command corresponding to a CLTM candidate has been received / acquired.

[0051] Optionally, the UE evaluates the execution conditions for each CLTM candidate in the CLTM configuration.

[0052] Optionally, the condition evaluation refers to determining whether the execution condition is met based on the corresponding measurement results. For example, when the execution condition is configured as an LTM-A3 measurement event (or measurement event LTM3), for a CLTM candidate, the evaluation assesses whether its associated measurement event is met. If met, the UE considers the candidate cell corresponding to the CLTM candidate to be a triggered cell. Optionally, if met, the UE can initiate a CLTM execution operation.

[0053] Optionally, for CLTM candidates based on layer 1, the CLTM condition evaluation is performed by the MAC layer; for CLTM candidates based on layer 3, the CLTM condition evaluation is performed by the RRC layer.

[0054] Optionally, in step 303: the UE stops the CLTM condition assessment by one or more of the following methods.

[0055] In one approach 1, when the RRC layer determines that a CLTM candidate configuration is associated with a Layer 3 execution condition, the RRC layer stops evaluating the corresponding CLTM condition. The CLTM candidate configuration being associated with a Layer 3 execution condition means that the CLTM candidate configuration (the candidate cell) is configured with a Layer 3-based execution condition.

[0056] Optionally, when the UE initiates the MCG failure information procedure at the RRC layer, the UE performs the operation in method 1 to stop the CLTM condition evaluation. Optionally, during the initialization phase of the MCG failure information procedure, the UE performs the operation in method 1. Optionally, the CLTM condition evaluation is for the MCG or SCG, that is, the CLTM candidate configuration is an LTM configuration associated with the MCG or an LTM configuration associated with the SCG.

[0057] Optionally, when the UE initiates the SCG failure information procedure, the UE performs the operation in method 1 to stop the CLTM condition evaluation. Optionally, during the initialization phase of the SCG failure information procedure, the UE performs the operation in method 1. Optionally, the CLTM condition evaluation is associated with the SCG.

[0058] Optionally, the RRC layer executes the operation in mode 1 only when it receives an indication from the MAC layer (lower layer) indicating that an LTM cell switch procedure has been triggered, or an indication that the execution conditions of a CLTM candidate have been met. Optionally, the CLTM condition evaluation is performed on the MCG or SCG, that is, the CLTM candidate configuration is an LTM configuration associated with the MCG or an LTM configuration associated with the SCG.

[0059] In one approach 2, when the UE's MAC entity performs a MAC entity reset operation, the MAC entity also stops the CLTM condition evaluation. Optionally, further, when the MAC entity determines that a Layer 1 execution condition is configured, the CLTM condition evaluation is stopped during the MAC reset operation. Optionally, being configured with a Layer 1 execution condition refers to an ongoing Layer 1-based CLTM condition evaluation, or being configured with a CLTM candidate configuration based on a Layer 1 execution condition.

[0060] Optionally, when a MAC entity receives a MAC entity reset request from an upper layer (such as the RRC layer), it performs a MAC reset operation. For example, when performing synchronization reconfiguration at the RRC layer, the RRC layer instructs the MAC layer to perform a MAC entity reset for the corresponding cell group; or when the RRC layer initiates the initialization operation of the MCG failure information process, the RRC layer instructs the MAC layer to perform a MAC entity reset for the corresponding cell group; or when the RRC layer initiates the initialization operation of the SCG failure information process, the RRC layer instructs the MAC layer to perform a MAC entity reset for the corresponding cell group. Optionally, the MAC entity reset is triggered by SCG deactivation.

[0061] In one approach 3, the UE's RRC layer instructs the MAC layer to stop CLTM condition evaluation. Optionally, the RRC layer performs the operation described in approach 3 when it determines that a CLTM candidate configuration is associated with a Layer 1 execution condition. Optionally, when the MAC layer receives a stop CLTM condition evaluation instruction / request from the RRC layer, the MAC layer stops the corresponding CLTM condition evaluation. Optionally, the MAC layer stops CLTM condition evaluation when it determines that a CLTM configuration is associated with a Layer 1 execution condition. Optionally, the instruction / request from the RRC layer to the MAC layer for stopping CLTM condition evaluation can be differentiated based on the CLTM candidate configuration. For example, if the UE is configured with three CLTM candidate configurations, corresponding to three CLTM candidate configuration identifiers #1, #2, and #3, and associated with three CLTM candidate cells, then the RRC layer may instruct the MAC layer to stop the condition evaluation operation for CLTM candidate configuration #1. In this case, the instruction or request from the RRC layer to the MAC layer for stopping CLTM condition evaluation is for a specific one or more CLTM candidate configurations (identifiers).

[0062] Optionally, when the UE initiates the MCG failure information procedure, the UE performs the operation in method 3 to stop the CLTM condition evaluation. Optionally, during the initialization phase of the MCG failure information procedure, the UE performs the operation in method 3. Optionally, the CLTM condition evaluation is for the MCG or the SCG, that is, the CLTM is an LTM configuration associated with the MCG or an LTM configuration associated with the SCG.

[0063] Optionally, when the UE performs the synchronization reconfiguration procedure, the UE performs the operation in mode 3 to stop the CLTM condition evaluation. Optionally, the CLTM condition evaluation is for the MCG or the SCG, that is, the CLTM is an LTM configuration associated with the MCG or an LTM configuration associated with the SCG.

[0064] In one approach 4, when the MAC layer determines that the LTM cell change (execution) has been successfully completed, the MAC entity stops the CLTM condition evaluation. Optionally, the MAC layer performs the operation described in approach 4 when it determines that one or more CLTM candidate configurations are associated with Layer 1 execution conditions.

[0065] Optionally, the MAC layer considers an LTM cell change to be successfully completed when one of the following conditions occurs: Condition 1: The random access procedure triggered by the LTM cell change process is successfully completed; Condition 2: The UE receives an uplink grant from the serving cell on the Physical Downlink Control Channel (PDCCH) scrambled with the Cell Radio Network Temporary Identifier (C-RNTI) of the MAC entity. This uplink grant is the first uplink grant received after the first Physical Uplink Shared Channel (PUSCH) transmission to the serving cell, and the uplink grant is for a new transmission using the same Hybrid Automatic Repeat reQuest (HARQ) process used for the first PUSCH transmission of the serving cell; and there is an ongoing RACH-less LTM cell change; Condition 3: The UE receives an uplink grant from the serving cell on the Physical Downlink Control Channel (PDCCH) scrambled with the Cell Radio Network Temporary Identifier (C-RNTI) of the MAC entity. A downlink assignment for a serving cell and a PDCCH timing is received on the Physical Downlink Control Channel (PDCCH) scrambled with an Identifier (C-RNTI). This downlink assignment is the first received downlink assignment after the first PUSCH transmission to the serving cell and is for a new transmission during an ongoing RACH-less LTM cell change.

[0066] In one approach 5, when the MAC layer determines that an LTM cell change (execution) has begun, the MAC entity stops CLTM condition evaluation. Optionally, the operation described in approach 5 is performed when the MAC layer determines that one or more CLTM candidate configurations are associated with Layer 1 execution conditions. Optionally, the MAC layer's determination that an LTM cell change has begun may also be due to the MAC layer determining that a CLTM cell change has been triggered, or that one or more CLTM candidate configurations are associated with (Layer 1 based) execution conditions that have been met. Optionally, this approach also includes the MAC layer indicating the target configuration identifier of the triggered CLTM, i.e., the target candidate configuration identifier, to the RRC layer.

[0067] Optionally, in one or more of the above methods, stopping the CLTM condition evaluation refers to stopping the condition evaluation operation of CLTM candidate configurations, where the CLTM candidate configurations are one or more CLTM candidate configurations indicated by a CLTM candidate configuration identifier. Stopping the condition evaluation of CLTM candidate configurations can be applied to all CLTM candidate configurations or to a subset of them.

[0068] Optionally, in one or more of the above methods, the operation of stopping CLTM condition evaluation is performed separately for cell groups, i.e., only for MCG or SCG; or it can be performed without distinguishing cell groups, i.e., for both MCG and SCG.

[0069] Optionally, Layer 1 refers to the physical layer in the access layer protocol. Optionally, Layer 3 refers to the RRC layer. The MAC layer and MAC entity are interchangeable. CLTM condition assessment, CLTM assessment, CLTM execution condition assessment, CLTM reconfiguration assessment, and LTM condition assessment are interchangeable.

[0070] In another implementation, the UE is simultaneously configured with both Layer 1 execution condition-based CLTM candidate configurations and Layer 3 execution condition-based CLTM candidate configurations. The MAC layer performs the CLTM condition evaluation corresponding to the Layer 1 execution condition-based CLTM candidate configuration, while the RRC layer performs the CLTM condition evaluation corresponding to the Layer 3 execution condition-based CLTM candidate configuration. When the MAC layer determines during the CLTM condition evaluation that the execution conditions corresponding to one or more CLTM candidate cells are met, the MAC layer indicates the candidate configuration identifier corresponding to the one or more CLTM candidate cells to the RRC layer, in order to inform the RRC layer that the execution conditions of this or these candidate cells have been met or that they are CLTM triggered cells. Upon receiving the instruction, if the RRC layer also finds that one or more CLTM candidate cells meet the execution conditions in the CLTM condition evaluation corresponding to the CLTM candidate configuration based on the layer 3 execution conditions, the RRC layer performs the following operations: Optionally, the RRC layer considers the candidate cells whose execution conditions are met as indicated by the MAC layer or the candidate cells whose execution conditions are met based on the layer 3 execution conditions to be triggered cells; Optionally, the RRC layer selects one of these triggered cells as the final cell switch target cell, applies the RRC reconfiguration message of that cell, and executes the cell switch execution process. Optionally, if there are multiple triggered cells (including both triggered cells based on Layer 1 execution conditions and triggered cells based on Layer 3 execution conditions), the RRC layer may preferentially select the triggered cells based on Layer 1 execution conditions; alternatively, if there are multiple triggered cells (including both triggered cells based on Layer 1 execution conditions and triggered cells based on Layer 3 execution conditions), the RRC layer may preferentially select the triggered cells based on Layer 3 execution conditions; alternatively, when selecting the final target cell for cell switching, the RRC layer may base its selection on both Layer 1 and Layer 3 measurement results.

[0071] Figure 4 is a block diagram illustrating a user equipment 400 according to an embodiment of the present disclosure. As shown in Figure 4, the user equipment 400 includes a processor 401 and a memory 402. The processor 401 may include, for example, a microprocessor, a microcontroller, an embedded processor, etc. The memory 402 may include, for example, volatile memory (such as random access memory, RAM), a hard disk drive (HDD), non-volatile memory (such as flash memory), or other memory. Program instructions are stored on the memory 402. When executed by the processor 401, these instructions can perform the methods described in detail in this disclosure within the user equipment.

[0072] A program running on a device according to this disclosure may be a program that enables a computer to perform the functions of embodiments of this disclosure by controlling a central processing unit (CPU). The program or the information processed by the program may be temporarily stored in volatile memory (such as random access memory RAM), hard disk drive (HDD), non-volatile memory (such as flash memory), or other memory systems.

[0073] Programs used to implement the functions of the embodiments of this disclosure can be recorded on a computer-readable recording medium. The corresponding functions can be implemented by causing a computer system to read and execute the programs recorded on the recording medium. The term "computer system" here can refer to a computer system embedded in the device, and may include an operating system or hardware (such as peripheral devices). "Computer-readable recording medium" can be a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a short-time dynamic storage program recording medium, or any other computer-readable recording medium.

[0074] Various features or functional modules of the devices used in the above embodiments can be implemented or executed by circuits (e.g., monolithic or multi-chip integrated circuits). Circuits designed to perform the functions described in this specification may include general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination of the above devices. A general-purpose processor may be a microprocessor, or any existing processor, controller, microcontroller, or state machine. The circuits described above may be digital circuits or analog circuits. In cases where advancements in semiconductor technology have led to new integrated circuit technologies that replace existing integrated circuits, one or more embodiments of this disclosure may also be implemented using these new integrated circuit technologies.

[0075] Furthermore, this disclosure is not limited to the embodiments described above. Although various examples of the embodiments have been described, this disclosure is not limited thereto. Fixed or non-mobile electronic devices installed indoors or outdoors can be used as terminal devices or communication devices, such as AV equipment, kitchen equipment, cleaning equipment, air conditioners, office equipment, vending machines, and other household appliances.

[0076] As described above, embodiments of this disclosure have been described in detail with reference to the accompanying drawings. However, the specific structure is not limited to the above embodiments, and this disclosure also includes any design modifications that do not depart from the spirit of this disclosure. Furthermore, various modifications can be made to this disclosure within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included within the technical scope of this disclosure. In addition, components with the same effects described in the above embodiments can be substituted for each other.

Claims

1. A method executed by a user equipment (UE), comprising: Receive a CLTM configuration containing one or more conditional layer 1 / layer 2 triggered mobility CLTM candidate configurations; Perform CLTM condition assessment; When performing the synchronous reconfiguration procedure, if the UE is performing LTM cell change condition assessment based on Layer 1 measurements, the Radio Resource Control (RRC) layer requests the Media Access Control (MAC) layer to stop the LTM condition assessment based on Layer 1 measurements for all CLTM candidate configurations.

2. The method according to claim 1, further comprising: When initiating the primary cell group MCG failure information process The RRC layer stops evaluating LTM cell change conditions based on layer 3 for all LTM candidate configurations associated with the MCG. If the UE is performing an LTM cell change condition assessment based on Layer 1 measurements, the RRC layer requests the MAC layer to stop the LTM condition assessment based on Layer 1 measurements for all CLTM candidate configurations.

3. A user equipment (UE) comprising a processing unit configured to: Receive a CLTM configuration containing one or more conditional layer 1 / layer 2 triggered mobility CLTM candidate configurations; Perform CLTM condition assessment; When performing the synchronous reconfiguration procedure, if the UE is performing LTM cell change condition assessment based on Layer 1 measurements, the Radio Resource Control (RRC) layer requests the Media Access Control (MAC) layer to stop the LTM condition assessment based on Layer 1 measurements for all CLTM candidate configurations.

4. The UE according to claim 3, further comprising: When initiating the primary cell group MCG failure information process The RRC layer stops evaluating LTM cell change conditions based on layer 3 for all LTM candidate configurations associated with the MCG. If the UE is performing an LTM cell change condition assessment based on Layer 1 measurements, the RRC layer requests the MAC layer to stop the LTM condition assessment based on Layer 1 measurements for all CLTM candidate configurations.

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