Handover information reporting method and user equipment

Abstract

The present disclosure provides a handover information reporting method and a user equipment (UE). The handover information reporting method comprises: a UE receives from a network side a successful handover report (SHR) configuration comprising first trigger information; and when the UE successfully completes handover to a target cell, the UE executes an operation for an SHR determination process, wherein the first trigger information is used for indicating that the SHR is generated when a CHO execution condition in the executed CHO configuration is satisfied before a CPAC execution condition in the CHO configuration.

Description

Handover information reporting method and user equipment Technical Field

[0001] The present disclosure relates to the technical field of wireless communications, and more particularly, to a handover information reporting method and corresponding user equipment when handover is performed in wireless communications. Background Art

[0002] The 3GPP RAN working group is currently conducting a research project for Release 18 (see 3GPP document RP-223520 (Revised WID on Further NR mobility enhancements). One of the research objectives of this project is to implement a conditional primary cell (PCell) change configuration in a dual connectivity (DC) scenario, which includes a process for adding or changing the configuration of a conditional primary secondary cell (PSCell). More specifically, simultaneous conditional primary cell switching can be achieved while conditional primary and secondary cell group cells can be added or changed, thereby supporting better dual connectivity continuity in the conditional switching scenario and improving throughput during the switching process.

[0003] The present disclosure proposes a solution to the problem of how to implement conditional switching in an NR system while reporting switching information when a conditional PSCell is added or changed.

[0004] Summary of the Invention

[0005] The purpose of the embodiments of the present disclosure is to provide a solution to the problem of how to implement handover information reporting during conditional handover in an NR system, accompanied by conditional PSCell addition or change. More specifically, the present disclosure provides a solution for how a handover event triggers a handover information report when conditional handover including conditional PSCell addition or change is configured, and how to record the corresponding handover information in the handover information report. The present disclosure provides a method for handover information reporting performed in a user equipment and a corresponding user equipment.

[0006] According to a first aspect of the present disclosure, a handover information reporting method is proposed, comprising:

[0007] The user equipment UE receives a successful switching report SHR configuration containing first trigger information from the network side; when the UE successfully completes the switching process to the target cell, the UE performs the operation for the SHR determination process; the first trigger information is used to indicate: if the CHO execution condition in the CHO configuration corresponding to the executed conditional switching CHO process is met before the execution condition of the conditional primary and secondary cell addition and change CPAC is met, then the SHR is generated when the switching process to the target cell is successfully completed.

[0008] In the handover information reporting method of the first aspect above, preferably, the first trigger information is configured by a target cell of the handover process.

[0009] In the handover information reporting method of the above-mentioned first aspect, preferably, the CHO configuration is a CHO configuration including a candidate secondary cell group SCG; the CHO execution condition is the execution condition configured by the condExecutionCond information element in the CHO configuration; the CPAC execution condition is the execution condition configured by the condExecutionCondPSCell information element in the CHO configuration; the CHO configuration is the CHO configuration saved in the UE variable VarConditionalReconfig.

[0010] In the switching information reporting method of the first aspect above, preferably, the operation of performing the SHR determination process includes: if the conditional switching performed is a conditional switching including a candidate SCG, and the CHO execution condition in the executed CHO configuration is satisfied before the execution condition of the CPAC therein, then the successful switching information of the switching event is saved in the UE variable used for SHR.

[0011] In the switching information reporting method of the first aspect above, preferably, the successful switching information includes one or more of the following information: first SHR information, used to indicate that the CHO execution condition in the CHO configuration corresponding to the executed conditional switching process is satisfied before the CPAC execution condition therein; second SHR information, used to indicate that the time difference between the satisfaction of the CHO execution condition in the CHO configuration corresponding to the executed conditional switching process and the CPAC execution condition is greater than or equal to a threshold value; third SHR information, used to indicate the time elapsed between the satisfaction of the CHO execution condition in the CHO configuration corresponding to the executed conditional switching process and the satisfaction of the CPAC execution condition; fourth SHR information, used to indicate that a neighboring cell is a primary and secondary cell PSCell cell in the candidate SCG in the CHO configuration; fifth SHR information, used to indicate the measurement results of the PSCell cell in the candidate SCG in the CHO configuration.

[0012] In the handover information reporting method of the first aspect, preferably, the first SHR information or the second SHR information is carried in an SHR-cause field.

[0013] In the handover information reporting method of the first aspect above, preferably, the fourth SHR information indicates that a neighboring cell in the measurement result is a PSCell cell in a candidate SCG in a CHO configuration; the CHO configuration is a CHO configuration in which the candidate target primary cell PCell in the CHO configuration is the same as the target cell of the successfully executed handover process.

[0014] In the switching information reporting method of the first aspect above, preferably, the switching information reporting method also includes: the UE receives a UE information request UEInformationRequest message from the network side, and the UEInformationRequest message carries a request for requesting the UE to report the saved SHR; and the UE includes the content of the saved SHR in a UE information response UEInformationResponse message, and sends a UEInformationResponse message to the network side.

[0015] According to a second aspect of the present disclosure, a user equipment (UE) is proposed, comprising: a processor; and a memory storing instructions; wherein the instructions, when executed by the processor, execute the handover information reporting method according to the context. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] For a more complete understanding of the present disclosure and its advantages, reference will now be made to the following description taken in conjunction with the accompanying drawings, in which:

[0017] FIG1 is a schematic diagram showing the configuration of a CHO including candidate SCGs in the present disclosure.

[0018] FIG2 is a schematic diagram showing multiple CHO configurations when a CHO candidate cell is associated with multiple candidate SCGs in the present disclosure.

[0019] FIG3 is a schematic flow chart showing a handover information reporting method in Embodiment 1 of the present disclosure.

[0020] FIG4 is a schematic flowchart showing a handover information reporting method in Embodiment 2 of the present disclosure.

[0021] FIG5 is a schematic flowchart showing a handover information reporting method in Embodiment 3 of the present disclosure.

[0022] FIG6 is a block diagram showing a user equipment UE involved in the present disclosure.

[0023] In the drawings, the same or similar structures are marked with the same or similar reference numerals. DETAILED DESCRIPTION

[0024] Other aspects, advantages, and salient features of the 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.

[0025] In this disclosure, the terms "include" and "contain" and their derivatives are intended to include but not limit; the term "or" is inclusive, meaning and / or. "If", "if", "in the case of" and "when" are interchangeable.

[0026] In this specification, the various embodiments described below for describing the principles of the present disclosure are merely illustrative and should not be construed in any way as limiting the scope of the disclosure. The following description with reference to the accompanying drawings is intended to assist in a comprehensive understanding of the exemplary embodiments of the present disclosure as defined by the claims and their equivalents. The following description includes a variety of specific details to aid understanding, but these details should be considered merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, for the sake of clarity and brevity, descriptions of well-known functions and structures have been omitted. In addition, throughout the drawings, the same reference numerals are used for similar functions and operations.

[0027] The following describes in detail multiple implementations of the present disclosure using the Long Term Evolution (LTE) / NR mobile communication system and its subsequent evolutionary versions as example application environments. However, the present disclosure is applicable to many other wireless communication systems. Unless otherwise specified, the concepts of cell and base station can be interchangeable; a cell can also be a cell under any type of base station mentioned above. Unless otherwise specified, cell, beam, and transmission point (TRP) can be interchangeable. A handover command is equivalent to a radio resource control (RRC) message containing a handover command, and refers to an RRC message or a configuration in an RRC message that triggers the UE to perform a handover. A handover configuration refers to all or part of the configuration in a handover command. Cancellation, release, deletion, clearing, and removal can be replaced. Execution, use, and application can be replaced. Configuration and reconfiguration can be replaced. Monitoring and detection can be replaced. Initiation and triggering can be replaced.

[0028] The following describes processes or concepts in the prior art to which this disclosure relates.

[0029] Handover configuration in NR system:

[0030] In the NR system, the RRC reconfiguration message for the handover command carries the RRC configuration from the target base station, including but not limited to the following RRC configuration (see section 6.2.2 of 3GPP technical standard protocol 38.331-h50 for details):

[0031] - measurement configuration;

[0032] -Cell group configuration (cellGroupConfig information element), used to configure the primary cell group or secondary cell group. It includes the radio link control (RLC) bearer configuration (rlc-bearerToAddModList information element and rlc-bearerToreleaselist information element) corresponding to the data radio bearer / signaling radio bearer, medium access control (MAC) configuration (MAC-cellgroupconfig information element), physical layer configuration, secondary cell addition / modification / release configuration, special cell (SpCell) configuration, etc. Among them, the reconfigurationwithsync information element contained in the SpCell configuration (spCellConfig information element) is similar to the mobility control information in the LTE system, and contains handover-related information to achieve mobility. It includes serving cell configuration public information (such as the identity and frequency information of the target serving cell), the cell radio network temporary identifier C-RNTI of the UE in the target cell, the handover process monitoring timer T304 configuration, and the random access dedicated configuration used for the random access process to the target cell.

[0033] -Radio bearer configuration (radiobearerConfig information element), used to configure the Service Data Application Protocol (SDAP) and Packet Data Convergence Protocol (PDCP) layers of the Data Radio Bearer (DRB) and / or Signaling Radio Bearer (SRB).

[0034] -Master key update configuration (masterKeyupdate information element).

[0035] Since the handover command is an RRC reconfiguration message containing a synchronous reconfiguration (Reconfiguration with sync) information element for the master cell group MCG, the handover can also be referred to as synchronous reconfiguration of the MCG.

[0036] Dual Connectivity (DC):

[0037] To improve the data transmission efficiency of the UE, the UE establishes links with two base stations at the same time. Among these two base stations, one is called the Master Node (MN) or MgNB, MeNB, and the service cell group under the Master Node is called the Master Cell Group (MCG); the other is called the Secondary Node (SN) or SgNB, SeNB, and the service cell group under the Secondary Node is called the Secondary Cell Group (SCG). The MCG contains at least one Primary Cell (PCell) and, optionally, one or more Secondary Cells (SCells). The PCell operates on the primary frequency, and the UE performs the initial connection establishment process or the connection re-establishment process through the primary frequency. The SCG contains at least one PSCell and, optionally, one or more SCells. The PSCell refers to the SCG cell to which the UE performs random access when performing the synchronization reconfiguration process or the SCG addition process. PCell and PSCell are also collectively referred to as special cells (SpCells).

[0038] Handover process in NR system:

[0039] User mobility in a connected primary cell is primarily achieved through a handover process, which refers to the process by which a UE in an RRC connected state changes its serving cell (primary cell). A typical handover process consists of the following phases: Phase 1: Measurement phase. The UE measures the radio link corresponding to the serving cell or neighboring cell based on the configured measurement configuration. When the configured measurement reporting conditions are met, the UE sends a measurement report to the base station. Phase 2: Handover preparation phase. The base station determines whether to trigger a handover for the UE based on the received measurement report and other factors, such as base station load. The source and target base stations obtain the handover command configured by the target base station through the handover preparation process. Phase 3: Handover execution phase. The source base station issues the handover command to the UE, which immediately applies the configuration of the handover command to execute the handover. The UE uses a timer, T304, to monitor the handover process. When the handover process is initiated, the UE starts T304; when the handover process is complete, the UE stops T304; when T304 expires, the UE considers the handover to have failed. The above handover process also applies to the PSCell change process.

[0040] Unlike the general handover process in stage 3, in which the UE performs handover immediately after receiving the handover command, the NR system also supports conditional handover CHO, also known as conditional reconfiguration. In conditional handover, a relatively conservative measurement report threshold is set so that the base station obtains the measurement results in advance and performs handover preparation in advance based on the measurement results and the selected target base station. In this way, the base station can send a handover command containing the handover candidate cell and the handover execution condition to the UE in advance before the actual handover condition (relative to the conservative measurement report threshold) is met, which carries the conditions for the UE to perform handover. After receiving the conditional handover command, the UE does not perform handover immediately, but saves the received handover command configuration and starts monitoring the link quality of the source cell or the link quality of the target cell according to the handover execution condition carried in the handover command message to evaluate whether the handover execution condition is met. Only when it is monitored that the configured handover execution condition is met, the UE starts to execute the saved handover command and accesses the target cell. The UE can be configured with multiple conditional handover candidate cells at the same time. If multiple conditional handover candidate cells meet the handover execution condition at the same time, the UE selects one candidate cell from them as the final conditional handover target cell and performs handover to that cell. In short, conditional handover refers to a handover process that is executed only when one or more configured handover execution conditions are met. Because the handover command is included in the RRC reconfiguration message, conditional handover is also called conditional reconfiguration.

[0041] PSCell change process in NR system

[0042] The PSCell change process in the NR system is triggered by the UE through the RRC reconfiguration message containing the synchronization reconfiguration information element for SCG. The PSCell change process can be initiated by the MN or the SN. When the Signaling Radio Bearer (SRB) 3 is configured, the SN can autonomously initiate the PSCell change process without the participation of the MN. At this time, the SN sends the PSCell change command for the SCG to the UE on SRB3. Generally speaking, the PSCell change initiated by the SN autonomously through SRB3 is Intra-SN, that is, the PSCell change within the same secondary base station. When SRB3 is not configured, whether the PSCell change process is initiated by the SN or the MN, the PSCell change command is sent to the UE on SRB1, including intra-SN or inter-SN PSCell changes. The RRC reconfiguration message of the PSCell change command for SN is included in the nr-SecondaryCellGroupConfig information element (when E-UTRAN is MN) or the mrdc-SecondaryCellGroup information element (when NR is MN) of its outer RRC message. The outer message is generally an RRC (connection) reconfiguration message or a DLInformationTransferMRDC message. The UE that receives the PSCell change command executes the PSCell change process, starts the timer T304 for monitoring the process of the SCG, starts downlink synchronization to the target PSCell, applies the configuration of the RRC reconfiguration message including the synchronization reconfiguration for the SCG, and sends an RRC reconfiguration completion message to the network side. Depending on the outer message of the received PSCell change command, the RRC reconfiguration completion message may also be embedded in an outer RRC message, such as an RRC (connection) reconfiguration completion message or a ULInformationTransferMRDC message.

[0043] After the introduction of conditional reconfiguration in the NR system, conditional reconfiguration is supported for adding or changing PSCells. Similar to conditional switching CHO, the UE is configured with conditional reconfiguration for SCG, which means that the conditional reconfiguration containing PSCell candidate cells and execution conditions is sent to the UE. After receiving the conditional reconfiguration, the UE does not immediately execute the addition or change of the PSCell candidate cells contained therein, but saves the received conditional reconfiguration and starts monitoring the link quality of the source cell or the link quality of the target candidate cell according to the execution conditions carried therein to evaluate whether the execution conditions are met. Only when it is monitored that the configured execution conditions are met, the UE starts to execute the SCG configuration in the saved conditional reconfiguration and accesses the selected PSCell candidate cell. Like CHO, the UE can be configured with multiple PSCell candidate cells at the same time. If multiple candidate cells meet the execution conditions at the same time, the UE selects one candidate cell as the final target PSCell cell and synchronizes to the cell. Conditional reconfiguration for SCGs is referred to as Conditional PSCell Addition Change (CPAC). Conditional PSCell Addition is also known as CPA (Conditional PSCell Addition), and Conditional PSCell Change is also known as CPC (Conditional PSCell Change). For ease of description, CPAC in this disclosure may refer to either CPC or CPA.

[0044] Conditional reconfiguration

[0045] As mentioned above, conditional reconfiguration can be applied to MCG or SCG. The conditional reconfiguration of MCG / PCell is called conditional handover CHO; the conditional reconfiguration of SCG / PSCell is called conditional PSCell addition or change CPAC. In the NR system, conditional reconfiguration is configured to the UE through the conditional reconfiguration ConditionalReconfiguration information element in the RRC message. The ConditionalReconfiguration information element contains a list of conditional reconfiguration candidate cells (condReconfigToAddModList information element for adding or modifying candidate cells or condReconfigToRemoveList information element for removing candidate cells). The UE saves the configuration corresponding to one or more of the conditional reconfiguration candidate cells in the UE variable VarConditionalReconfig. In the NR system of version 17, the UE maintains two VarConditionalReconfig variables, which are used to save the CHO configuration of the MCG and the CPAC configuration of the SCG respectively. Among the one or more conditional configuration items stored in each variable, each item is identified by a conditional reconfiguration identifier (condReconfigId), including an execution condition (condExecutionCond or condExecutionCondSCG) and the RRC configuration of the candidate cell (condRRCReconfig). The RRC configuration of the candidate cell contains a nested RRC reconfiguration message, in which the cell identified by the cell identifier in the serving cell common configuration (servingCellConfigCommon information element) in the synchronous reconfiguration (reconfigurationWithSync information element) corresponds to a conditional reconfiguration candidate cell. The UE performs conditional reconfiguration evaluation on each conditional reconfiguration candidate cell based on the execution condition. The execution condition can include one or two measurement identifiers (measID). Only when the measurement events corresponding to all measurement identifiers included in the execution condition (such as condEventA3 or CondEventA5 included in the CondTriggerConfig information element) are met, the UE considers the corresponding candidate cell to be a triggering cell and initiates the conditional reconfiguration execution process.During the conditional reconfiguration execution process, the UE applies the saved RRC configuration (condRRCReconfig) corresponding to the selected triggering cell to the selected cell and performs the cell change operation, such as starting timer T304, downlink synchronization to the selected cell, initiating a random access process to the selected cell for uplink synchronization, and sending an RRC reconfiguration completion message to the selected cell (see section 5.3.5.3 of the 3GPP protocol specification document TS38.331 for details, which will not be repeated here). In this disclosure, unless otherwise specified, CHO and CHO configurations can be replaced, and CPAC and CPAC configurations can be replaced.

[0046] CHO with candidate SCG for CPAC:

[0047] Release 17 NR systems support CHO with SCG configurations. This means that each CHO candidate cell configuration includes not only the corresponding MCG configuration but also the SCG configuration. However, during CHO execution, the included SCG configuration may not be appropriate, which can lead to SCG failures during CHO execution (e.g., failure to add or change a PSCell).

[0048] In the mobility enhancement discussion of Release 18 currently underway in 3GPP, in order to solve the above-mentioned problem, it is proposed that the CHO configuration can be associated with one or more CPAC configurations. Unlike Release 17, which contains a fixed SCG configuration in the CHO configuration, the CHO configuration proposed in Release 18 can contain or be associated with one or more candidate SCG configurations, and each candidate SCG configuration is equivalent to a CPAC configuration. When the UE receives the CHO configuration and the associated CPAC configuration, it can simultaneously start the CHO conditional reconfiguration evaluation and the corresponding associated CPAC conditional reconfiguration evaluation. In this way, when the execution condition of CHO is met, that is, when CHO is triggered, the UE can select the most suitable SCG configuration from multiple candidate SCG configurations according to the corresponding CPAC execution condition evaluation for PSCell access. This can greatly reduce the problem of SCG failure or SCG inappropriateness in the CHO process caused by only one fixed SCG configuration in the CHO configuration in Release 17. In this disclosure, the CHO configuration in this newly introduced mechanism is referred to as a CHO configuration associated with a CPAC configuration, a CHO configuration that includes a CPAC configuration, a CHO configuration with a candidate SCG for a CPAC, a CHO configuration with a candidate CPAC (configuration), or a CHO configuration that includes a candidate SCG. However, it is worth noting that this disclosure is not limited to the above nomenclature. The following references to the CHO (configuration) include a candidate SCG.

[0049] In the CHO configuration that includes a candidate SCG, the CHO configuration (a CondReconfigToAddMod configuration) includes an RRC reconfiguration message (including an MCG configuration and an SCG configuration), a CHO execution condition (such as identified by condExecutionCond) and a CPAC execution condition (such as identified by condExecutionCondPSCell), and is identified by a CHO identification number CondReconfigId, as shown in Figure 1. If a CHO candidate cell is associated with multiple candidate SCG configurations, then for this CHO candidate cell, the network side will configure multiple CHO configurations for the UE, and each CHO configuration includes an MCG configuration and an SCG configuration. That is, the CHO candidate cell identifiers in multiple conditional reconfigurations (identified by condReconfigId) can be the same, but correspond to different CPAC candidate cell identifiers. As shown in Figure 2, multiple CHO configurations are configured for PCell 1, each CHO configuration corresponds to a different PSCell, and these multiple CHO configurations are identified by different CondReconfigId.

[0050] In the above scenario, when the UE receives an RRC message containing the CPAC configuration of CHO and the associated alternative SCG, the UE saves the received CHO configuration and CPAC configuration, and starts the corresponding conditional reconfiguration evaluation at the same time. According to the conclusion reached by the 3GPP working group, only when the execution conditions of CHO are met and the associated CPAC execution conditions are also met, the UE triggers and executes the CHO process accompanied by CPAC, and at the same time triggers and completes the switching and PSCell addition or change. If the execution conditions of CHO are met but the execution conditions of the associated CPAC are not met, in this case, if the UE is configured with the traditional CHO configuration, the UE triggers the execution of the CHO process and applies the configured traditional CHO configuration. In the present disclosure, the traditional CHO configuration refers to a CHO configuration that does not include a CPAC configuration or a CHO configuration that does not include a candidate SCG configuration (that is, the CHO configuration does not include a CPAC execution condition), such as the CHO configuration that does not include an SCG configuration introduced in version 16 or the CHO configuration that includes an SCG configuration introduced in version 17 (which does not include the CPAC execution condition configuration corresponding to the SCG configuration).

[0051] Successful switch report:

[0052] The handover information report upon successful handover is standardized in the NR system of version 17. The handover information report upon successful handover is also referred to as a Successful Handover Report (SHR), which is used to provide the network side with mobility information related to the successful execution of the handover process, so that the network side can further optimize the configuration of mobility parameters based on the information reported by these UEs, and improve the handover performance, such as reducing the handover delay. The content of the successful handover information report may include one or more of the following: UE Radio Network Temporary Identifier C-RNTI, source cell identifier, target cell identifier, measurement results of the source cell or target cell, neighbor cell measurement results, indication of the reason why the successful handover information report is triggered (i.e., which triggering condition is met), random access process information, and location information, etc. The successful handover includes the successful sending of an RRC reconfiguration completion message for responding to the handover command RRC reconfiguration message to the target base station or the successful completion of the random access process to the target base station by the MAC layer. The network side configures the UE with information used to trigger a successful handover report (such as the thresholds corresponding to T310, T312, and T304, and the source cell experiencing a radio link failure (RLF) during a Dual Active Protocol Stack (DAPS) handover). This is called SHR configuration. The UE will record the handover information of the successful handover in the UE variable corresponding to the SHR (such as VarSuccessHO-Report) only when one or more trigger conditions based on the configured trigger information are met (such as the percentage of the running value of T310 (or T312) of the source cell to the configured value of T310 (or T312) exceeds the corresponding configured threshold when a handover command is received or when a handover is executed, the percentage of the running value of T304 to the configured value of T304 when the handover is successfully completed exceeds the corresponding configured threshold, or the source cell experiences an RLF during a DAPS handover (when timer T304 is running). Among them, the trigger conditions related to the source cell, such as the T310 threshold value or the T312 threshold value, are configured by the source cell to the UE, and the trigger conditions related to the target cell, such as the T304 threshold value, are configured by the target cell to the UE. The configuration of these successful handover report triggering information is included in the successful handover report configuration (such as the successHO-config information element). The UE can inform the network side through an RRC message that there is an available successful handover report (such as indicated by the successHO-InfoAvailable information element). After receiving the indication, the network side can request the UE to report its saved successful handover information report through an RRC message (such as the successHO-ReportReq indication in the UEInformationRequest message).The UE will report the saved success handover report (successHO-Report in the UEInformationResponse message) to the network side in the response RRC message. The successful handover report saved on the UE can be saved for up to 48 hours.

[0053] The SHR mechanism in version 17 takes into account traditional switching, conditional switching, and DAPS switching scenarios, and has not yet implemented enhancements to the CHO mechanism including candidate SCGs introduced in version 18. For example, in the CHO mechanism including candidate SCGs, the following two scenarios may exist. In scenario 1, for a UE configured with a CHO configuration including candidate SCGs, if the execution conditions for a certain CHO candidate cell have been met, but the execution conditions corresponding to the SCG to which it is associated or included are met afterwards, the UE triggers the CHO execution process accompanied by CPAC execution and successfully switches to that CHO candidate cell and the corresponding PSCell. In this scenario, the execution conditions of CHO are met before the execution conditions of the included SCGs, that is, the execution time of CHO is delayed by the execution of the candidate SCG, which is not an optimal situation. In the optimal case, the execution conditions of the candidate SCG should be met at the same time as the execution conditions of the associated CHO or in advance of the execution conditions of the associated CHO, so as not to delay the execution of CHO. In scenario 2, for a UE configured with a CHO configuration that includes a candidate SCG, if the execution conditions for a certain CHO candidate cell have been met, but the execution conditions corresponding to the SCG to which it is associated or included have not been met, if the UE is also configured with a traditional CHO configuration for the CHO candidate cell (i.e., the CHO configuration for the CHO candidate cell that does not include the candidate SCG and its execution conditions), then the UE can perform conditional reconfiguration to the CHO candidate cell based on the traditional CHO configuration. Considering the CHO mechanism in the above scenario that includes a candidate SCG, how to trigger the UE to record the SHR and how to report the SHR to the network side become issues that need to be addressed.

[0054] The following embodiments provide solutions to the above problems. Unless otherwise specified, the embodiments are not mutually exclusive and can be combined, or some concepts or definitions can be common among the embodiments.

[0055] Example 1

[0056] This embodiment provides a method for configuring, triggering, and setting a handover information report executed on a UE. Through the method described in this embodiment, the UE receives an SHR configuration from the network side, which includes trigger information related to the CHO including a candidate SCG. After the handover process is successful, the UE can trigger the UE to record the handover information SHR of the handover event based on the configured trigger information, and report it to the network to adjust and optimize the handover parameters.

[0057] The following describes the embodiment 1 of the present disclosure in detail. FIG3 is a schematic flow chart showing the handover information reporting method in the embodiment 1 of the present disclosure. As shown in FIG3 , the handover information reporting method in the embodiment 1 of the present disclosure may include the following steps.

[0058] Step 101: The UE receives an SHR configuration including first trigger information from the network side.

[0059] In one implementation method 1, the first trigger information is set to true, indicating that if the CHO execution condition in the CHO configuration corresponding to the conditional switching process executed is satisfied before the CPAC execution condition therein, or the CPAC execution condition in the CHO configuration is satisfied after the CHO execution condition is satisfied, then the UE generates an SHR when the switching process to the target cell is successfully completed.

[0060] In another implementation manner 2, the first trigger information is set to a threshold value TH, indicating that if the time difference between the satisfaction of the CHO execution condition and the CPAC execution condition in the CHO configuration corresponding to the executed conditional handover procedure exceeds or equals the threshold value TH, then the UE generates an SHR when the handover procedure to the target cell is successfully completed. Furthermore, when the CHO execution condition is satisfied before the CPAC execution condition therein is satisfied, the UE generates an SHR when the handover procedure to the target cell is successfully completed.

[0061] Optionally, the CHO execution condition refers to the execution condition configured with the condExecutionCond information element in the CHO configuration, and the CPAC execution condition refers to the execution condition configured with the condExecutionCondPSCell information element in the CHO configuration. The CPAC execution condition and the execution condition of the (candidate) SCG can be interchangeable. Optionally, because either the CHO execution condition or the CPAC execution condition can be configured with one or two triggering events (Meas Ids), the execution condition being satisfied means that all one or both triggering events configured for the candidate cell are satisfied.

[0062] Optionally, the first trigger information is configured by the target cell or the source cell of the handover process.

[0063] As previously mentioned, the SHR configuration includes a configuration for instructing the UE to report successful handover information to the network. Optionally, in the NR system, this is identified by the successHO-Config information element and included in the other-config information element of the RRC message. Optionally, the SHR configuration is included in the CHO configuration. Furthermore, each CHO configuration includes an SHR configuration.

[0064] When the UE receives an RRC message including an SHR configuration, the UE applies the SHR configuration and considers that it is configured with the SHR configuration.

[0065] Step 102: When the UE successfully completes the conditional handover process to the target cell, the UE performs operations for the SHR determination process. The operations for the SHR determination process may include: determining whether the trigger condition is met based on trigger information in the SHR configuration, and saving the SHR and setting corresponding content in the SHR when the trigger condition is met.

[0066] In combination with the first trigger information in step 101, executing the operation for the SHR determination process may include: for the first trigger information of implementation method 1, if the conditional switching performed is a conditional switching including a candidate SCG (that is, the switching process simultaneously has a PCell triggered based on the execution condition and a triggered PSCell), and the CHO execution condition in the CHO configuration corresponding to the conditional switching process performed is satisfied before the execution condition of the CPAC / SCG therein, or the execution condition of the CPAC in the CHO configuration is satisfied after the CHO execution condition is satisfied, then the successful switching information of the switching event is saved in the UE variable for SHR; for the first trigger information of implementation method 2, if the conditional switching performed is a conditional switching including a candidate SCG (that is, the switching process simultaneously has a PCell triggered based on the execution condition and the triggered PSCell), and the time difference between the satisfaction of the CHO execution condition and the CPAC execution condition in the CHO configuration corresponding to the executed conditional switching process exceeds or is equal to the threshold value TH contained in the SHR configuration; optionally, the CHO execution condition is satisfied before the CPAC execution condition is satisfied, then the successful switching information of the switching event is saved in the UE variable used for SHR.

[0067] Optionally, the SHR configuration is further described as the SHR configuration (received or applied) before performing the handover process, ie, performing the most recent synchronization reconfiguration.

[0068] Optionally, the successful completion of the handover to the target cell refers to the successful completion of the random access process triggered by the handover process of the MCG.

[0069] Optionally, the storing of the successful switching information of the switching event is the operation described in step 202 in embodiment 2, that is, setting the first to fifth SHR information.

[0070] Optionally, before or between step 101 and step 102, the UE also performs a conditional reconfiguration evaluation process. When the triggering condition of the conditional reconfiguration is met (that is, it is determined that there is a triggering cell in the conditional reconfiguration evaluation process), a switching process based on the conditional reconfiguration is performed.

[0071] Example 2

[0072] This embodiment provides a handover information reporting method executed on a UE. Using the method described in this embodiment, a UE configured with a CHO including a candidate SCG records handover information related to the configured CHO including the candidate SCG in an SHR after a successful handover process, and reports the information to the network for adjustment and optimization of handover parameters.

[0073] The following describes the embodiment 2 of the present disclosure in detail. FIG4 is a schematic flow chart showing the handover information reporting method in the embodiment 2 of the present disclosure. As shown in FIG4 , the handover information reporting method in the embodiment 2 of the present disclosure may include the following steps.

[0074] Step 201: The handover process is successfully completed, and the SHR determination process is performed.

[0075] In this step, when the UE is configured with an SHR configuration when connected to the source cell, the UE initiates an SHR determination process when the handover process is successfully completed.

[0076] Optionally, when the UE receives an RRC message including an SHR configuration, the UE applies the SHR configuration and considers that it is configured with the SHR configuration.

[0077] Optionally, the successful completion of the handover to the target cell refers to the successful completion of the random access process triggered by the handover process of the MCG.

[0078] Optionally, the successfully completed handover process is a conditional handover.

[0079] Step 202: In performing the operation for the SHR determination process, the UE includes one or more of the following in the SHR:

[0080] The first SHR information is used to indicate that the CHO execution condition in the CHO configuration corresponding to the executed conditional switching process is satisfied before the CPAC / SCG execution condition therein, or that the CPAC execution condition in the CHO configuration is satisfied after the CHO execution condition is satisfied.

[0081] Optionally, in the following circumstances, the UE includes the first SHR information or the following third to fifth SHR information in the SHR: the conditional switching performed by the SHR is a conditional switching including a candidate SCG (i.e., the switching process simultaneously includes a PCell triggered based on the execution condition and a PSCell triggered), and the CHO execution condition in the CHO configuration corresponding to the executed conditional switching process is satisfied before the execution condition of the CPAC / SCG therein, or the execution condition of the CPAC in the CHO configuration is satisfied after the CHO execution condition is satisfied.

[0082] The second SHR information indicates that the time difference between the satisfaction of the CHO execution condition and the CPAC execution condition in the CHO configuration corresponding to the executed conditional handover process exceeds or equals the threshold value TH included in the SHR configuration. Furthermore, it also indicates that the satisfaction of the CHO execution condition precedes the satisfaction of the CPAC execution condition.

[0083] Optionally, in the following circumstances, the UE includes the second SHR information or the third to fifth SHR information in the SHR: the conditional switching performed is a conditional switching including a candidate SCG (i.e., the switching process simultaneously includes a PCell triggered based on the execution condition and a PSCell triggered), and the time difference between the satisfaction of the CHO execution condition and the satisfaction of the CPAC execution condition in the CHO configuration corresponding to the executed conditional switching process (optionally, the satisfaction of the CHO execution condition precedes the satisfaction of the CPAC execution condition and) exceeds or is equal to the threshold value TH included in the SHR configuration.

[0084] Optionally, the first SHR information and the second SHR information are carried by an SHR-cause field.

[0085] The third SHR information is used to indicate the time (time difference) elapsed between the time when the CHO execution condition in the CHO configuration corresponding to the executed conditional handover process is satisfied and the time when the CPAC execution condition is satisfied.

[0086] Optionally, the third SHR information does not limit whether the CHO execution condition or the execution condition corresponding to its associated candidate SCG is satisfied first. That is, the third SHR information can be the time elapsed from the time the CHO execution condition is satisfied to the time the CPAC execution condition is satisfied in the CHO configuration corresponding to the executed conditional switching process, or it can be the time elapsed from the time the CPAC execution condition is satisfied to the time the CHO execution condition is satisfied in the CHO configuration corresponding to the executed conditional switching process.

[0087] The fourth SHR information is used to indicate whether the neighboring cell is a PSCell cell in the candidate SCG in the CHO configuration.

[0088] Optionally, the neighboring cell refers to one or more neighboring cells in a neighboring cell measurement result list (for example, identified by a measResultNeighCells information element).

[0089] Optionally, if a neighboring cell is a candidate target PSCell in a candidate SCG configuration included in a CHO configuration, the fourth SHR information is set to true.

[0090] Optionally, the CHO configuration refers to a CHO configuration in which a candidate PCell in the CHO configuration is the same as a target cell of a successfully executed handover process. That is, the candidate target PCell in the CHO configuration is the target cell of the successfully executed handover.

[0091] The fifth SHR information is used to indicate the measurement results of the PSCell cells in the candidate SCG in one or more CHO configurations. The CHO configuration refers to a CHO configuration in which the candidate PCell in the CHO configuration is the same as the target cell of the successfully executed handover process. In other words, the candidate target PCell in the CHO configuration is the target cell of the successfully executed handover.

[0092] Optionally, the CHO configuration is an active cell configuration, the CHO execution condition refers to the execution condition configured with the condExecutionCond information element in the CHO configuration, and the CPAC execution condition refers to the execution condition configured with the condExecutionCondPSCell information element in the CHO configuration. Optionally, because both the CHO execution condition and the CPAC execution condition can be configured with one or two triggering events (Meas Ids), the execution condition being satisfied means that all one or both triggering events configured for the candidate cell are satisfied.

[0093] Optionally, when the successful handover process is a conditional handover process, that is, the performed RRC reconfiguration including the synchronous reconfiguration information element is included in a conditional reconfiguration, the UE sets or includes the fourth SHR information or the fifth SHR information in the SHR.

[0094] Optionally, the SHR configuration is further described as the SHR configuration (received or applied) before performing the handover process, ie, performing the most recent synchronization reconfiguration.

[0095] Optionally, the SHR configuration is an SHR configuration received when connecting to a source cell.

[0096] Optionally, the successful completion of the handover to the target cell refers to the successful completion of the random access process triggered by the handover process of the MCG.

[0097] Optionally, in step 202, the UE includes the first to fifth SHR information in the SHR only when the SHR is configured with the SHR configuration in embodiment 1. Optionally, in step 202, the UE includes the first to fifth SHR information in the SHR when the UE is configured with other SHR configurations and the configured SHR configurations are satisfied.

[0098] Optionally, before step 201, the UE also includes receiving a handover command from the network and executing a handover process; or the UE executes a conditional reconfiguration evaluation process, and when the triggering condition of the conditional reconfiguration is met (that is, it is determined that there is a triggering cell in the conditional reconfiguration evaluation process), a handover process based on the conditional reconfiguration is executed.

[0099] Example 3

[0100] This embodiment provides a method for reporting handover information performed on a UE. Using the method described in this embodiment, the UE can report the relevant information in the aforementioned embodiments to the base station in a successful handover report, thereby providing more accurate handover information to the network. This embodiment provides a method for the UE to report the handover information described in Embodiment 1 or Embodiment 2 through an RRC process.

[0101] The following describes the embodiment 3 of the present disclosure in detail. Figure 5 is a schematic flow chart showing the handover information reporting method in the embodiment 3 of the present disclosure. As shown in Figure 5 , the handover information reporting method in the embodiment 3 of the present disclosure may include the following steps.

[0102] Step 301: The UE receives a UEInformationRequest message from the network side, which carries an indication / request for requesting the UE to report a saved successful handover report (eg, a successHO-ReportReq information element set to true).

[0103] Step 302: The UE includes the content of the saved successful handover report in a UEInformationResponse message (such as the successHO-Report information element therein), and sends a UEInformationResponse message to the network side. The successful handover report included in the RRC message includes one or more of the first to fifth SHR information in the above-mentioned embodiment 1 or embodiment 2.

[0104] It should be noted that the handover information report in the aforementioned embodiment of the present disclosure is described by taking SHR as an example, but the report is not limited to SHR and may also refer to reports of other commands.

[0105] Example 4

[0106] This embodiment illustrates the user equipment UE of the present disclosure. Figure 6 is a block diagram of the user equipment UE involved in the present disclosure. As shown in Figure 6, the user equipment UE10 includes a processor 101 and a memory 102. The processor 101 may include, for example, a microprocessor, a microcontroller, an embedded processor, etc. The memory 102 may include, for example, a volatile memory (such as a random access memory RAM), a hard disk drive (HDD), a non-volatile memory (such as a flash memory), or other memory, etc. Program instructions are stored on the memory 102. When the instructions are executed by the processor 101, the above-mentioned handover information reporting method described in detail in the present invention can be executed.

[0107] The method and related devices of the present disclosure have been described above in conjunction with preferred embodiments. Those skilled in the art will appreciate that the method shown above is merely exemplary. The method of the present disclosure is not limited to the steps and sequence shown above. The base station and user equipment shown above may include more modules, for example, modules that can be developed or will be developed in the future and can be used for the base station, MME, or UE, etc. The various identifiers shown above are merely exemplary and not restrictive, and the present disclosure is not limited to the specific information elements used as examples of these identifiers. Those skilled in the art may make many changes and modifications based on the teachings of the illustrated embodiments.

[0108] The program running on the device according to the present disclosure may be a program that controls a central processing unit (CPU) to enable a computer to implement the functions of the embodiments of the present disclosure. The program or the information processed by the program may be temporarily stored in a volatile memory (such as a random access memory RAM), a hard disk drive (HDD), a non-volatile memory (such as a flash memory), or other memory systems.

[0109] The program for realizing each embodiment function of the present disclosure can be recorded on a computer-readable recording medium. The corresponding function can be realized by making a computer system read the program recorded on the recording medium and executing these programs. The so-called "computer system" herein can be a computer system embedded in the device, and can include an operating system or hardware (such as a peripheral device). "Computer-readable recording medium" can be a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a short-term dynamic storage program recording medium or any other recording medium that is computer-readable.

[0110] The various features or functional modules of the devices used in the above embodiments can be implemented or executed by circuits (e.g., single-chip or multi-chip integrated circuits). The circuits designed to perform the functions described in this specification may include a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination of the above devices. The general-purpose processor may be a microprocessor, or any existing processor, controller, microcontroller, or state machine. The above circuits may be digital circuits or analog circuits. In the case where new integrated circuit technologies have emerged to replace existing integrated circuits due to advances in semiconductor technology, one or more embodiments of the present disclosure may also be implemented using these new integrated circuit technologies.

[0111] Furthermore, the present disclosure is not limited to the above-described embodiments. Although various examples of the embodiments have been described, the present 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.

[0112] As described above, the embodiments of the present disclosure have been described in detail with reference to the accompanying drawings. However, the specific structure is not limited to the above-mentioned embodiments, and the present disclosure also includes any design changes that do not deviate from the main purpose of the present disclosure. In addition, various modifications can be made to the present disclosure within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present disclosure. In addition, components with the same effect described in the above-mentioned embodiments can be replaced with each other.

Claims

1. A handover information reporting method, comprising: The user equipment UE receives a successful handover report SHR configuration including first trigger information from the network side; When the UE successfully completes the handover process to the target cell, the UE performs an operation for the SHR determination process; The first trigger information is used to indicate: if the CHO execution condition in the CHO configuration corresponding to the executed conditional switching CHO process is met before the execution condition of the conditional primary and secondary cell addition and change CPAC is met, then SHR is generated when the switching process to the target cell is successfully completed.

2. The handover information reporting method according to claim 1, wherein: The first trigger information is configured by a target cell of the handover process.

3. The handover information reporting method according to claim 1, wherein: The CHO configuration is a CHO configuration including a candidate secondary cell group SCG; The CHO execution condition is the execution condition configured by the condExecutionCond information element in the CHO configuration; The CPAC execution condition is the execution condition configured with the condExecutionCondPSCell information element in the CHO configuration; The CHO configuration is the CHO configuration saved in the UE variable VarConditionalReconfig.

4. The handover information reporting method according to claim 1, wherein: The operations for executing the SHR determination process include: if the conditional switching performed is a conditional switching including a candidate SCG, and the CHO execution condition in the executed CHO configuration is satisfied before the execution condition of the CPAC therein, then the successful switching information of the switching event is saved in the UE variable for SHR.

5. The handover information reporting method according to claim 4, wherein: The successful switching information includes one or more of the following information: The first SHR information is used to indicate the CHO corresponding to the conditional switching process executed. The execution conditions of CHO in the configuration are met before the execution conditions of CPAC in it; The second SHR information is used to indicate that the time difference between the CHO execution condition and the CPAC execution condition in the CHO configuration corresponding to the executed conditional switching process is greater than or equal to a threshold value; The third SHR information is used to indicate the time elapsed between the CHO execution condition in the CHO configuration corresponding to the executed conditional switching process being satisfied and the CPAC execution condition being satisfied; The fourth SHR information is used to indicate that a neighboring cell is a primary and secondary cell PSCell cell in a candidate SCG in the CHO configuration; The fifth SHR information is used to indicate the measurement results of the PSCell cells in the candidate SCG in the CHO configuration.

6. The handover information reporting method according to claim 5, wherein: The first SHR information or the second SHR information is carried in the SHR-cause field.

7. The handover information reporting method according to claim 5, wherein: Fourth SHR information, indicating that a neighboring cell in the measurement result is a PSCell cell in a candidate SCG in a CHO configuration; The CHO configuration is a CHO configuration in which a candidate target primary cell PCell in the CHO configuration is the same as a target cell of the successfully performed handover process.

8. The handover information reporting method according to claim 1, wherein: The switching information reporting method further includes: The UE receives a UE information request UEInformationRequest message from the network side, where the UEInformationRequest message carries a request for requesting the UE to report the stored SHR; and The UE includes the content in the stored SHR in a UE information response UEInformationResponse message, and sends the UEInformationResponse message to the network side.

9. A user equipment, comprising: processor; as well as A memory, wherein instructions are stored in the memory; When the instruction is executed by the processor, the user equipment executes the switching information reporting method according to any one of claims 1-8.

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