Communication method, device and system

Abstract

The invention provides a communication method, device and system. The method comprises the following steps: receiving first indication information from first network equipment, wherein the first indication information is used for requesting terminal equipment to report first information; and reporting the first information to the first network device, wherein the first information comprises related information in a condition switching process. Based on the scheme, the terminal equipment can report the recorded related information in the condition switching process to the first network equipment, so that the first network equipment or other network equipment can adjust the switching parameters (such as traditional switching configuration information or condition switching configuration information) according to the obtained related information; therefore, the reliability and robustness of the system are improved.

Description

[0001] This application is a divisional application. The application number of the original application is 201980101967.X, and the original application date is November 8, 2019. The entire contents of the original application are incorporated into this application by reference. Technical Field

[0002] The present application relates to the field of mobile communication technologies, and in particular to communication methods, devices and systems. Background Art

[0003] In the traditional switching mechanism, the network device sends a switching message containing the configuration information of the target cell to the terminal device, so that the terminal device attempts to access or switch to the target cell according to the configuration information. In the traditional switching, the successful sending of the switching message is a necessary condition to ensure the successful switching under the traditional switching mechanism. However, due to the rapid attenuation of channel quality, the rapid movement of the terminal device and the obstruction of objects, or the long duration of measurement and switching preparation, the switching message may fail to be sent, which in turn leads to the failure of the switching and reduces the success rate of the switching.

[0004] In view of the above problems of traditional handover, a conditional handover mechanism is currently proposed to improve the success rate and robustness of handover. In the conditional handover mechanism, the network device sends configuration information of at least one candidate cell to the terminal device, so that the terminal device determines the target cell according to the configuration information and attempts to access or switch to the target cell, wherein the target cell belongs to the at least one candidate cell.

[0005] Whether in the traditional handover mechanism or the conditional handover mechanism, the handover parameters (such as the configuration information of the target cell, the configuration information of at least one candidate cell, etc.) are always one of the key factors affecting the success rate of the traditional handover and the conditional handover. In order to optimize the handover parameters in the traditional handover mechanism, the mobility robustness optimization (MRO) mechanism is introduced, that is, the terminal device reports the relevant information in the traditional handover process, and then the network device can optimize the handover parameters according to the relevant information reported by the terminal device.

[0006] The current mobility robustness optimization mechanism is only for the traditional switching mechanism. However, there is no corresponding mobility robustness optimization mechanism for the conditional switching mechanism. Summary of the invention

[0007] The present application provides a communication method, device and system for reporting relevant information in a conditional switching process to improve system reliability and robustness.

[0008] In a first aspect, the present application provides a communication method, comprising: receiving first indication information from a first network device, the first indication information being used to request a terminal device to report first information; reporting the first information to the first network device; wherein, when a wireless link failure, a traditional switching failure, or a terminal device fails to access a first candidate cell that meets the execution conditions of the conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information includes one or more of the following: identification information of the first cell, index information corresponding to the first cell, signal quality corresponding to the first cell when the terminal device successfully accesses the first cell, a success reason value, or indication information that the first cell meets the cell selection criteria and access is successful; wherein the first cell belongs to the first network device, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is the network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0009] Based on the above scheme, the terminal device can report the relevant information in the recorded conditional switching process to the first network device, so that the first network device or other network devices can adjust the switching parameters (such as traditional switching configuration information or conditional switching configuration information) according to the relevant information obtained, thereby improving the system reliability and robustness.

[0010] In a possible implementation method, before receiving the first indication information from the first network device, the method further includes: receiving indication information for instructing to record the first information. The indication information may be called second indication information. The second indication information may come from the second network device.

[0011] In a possible implementation method, before receiving the first indication information from the first network device, the method further includes: sending indication information to the first network device indicating that the recording of the first information has been completed. The indication information may be referred to as third indication information. The third indication information may be sent to the first network device.

[0012] Optionally, the second indication information may be included in an RRC reconfiguration message (the RRC reconfiguration message may be an RRC message including CHO configuration information, or an RRC message for traditional switching (i.e., a switching message)). The UE may include the relevant information recorded in the corresponding scenario (i.e., part or all of the first information) in an RRC reconfiguration completion message sent to a network device to which the first cell successfully accessed belongs. Optionally, the third indication information may also be included in an RRC reconfiguration completion message.

[0013] In a second aspect, the present application provides a communication method, comprising: receiving first indication information from a first network device, the first indication information being used to request a terminal device to report first information; reporting the first information to the first network device; wherein, after the terminal device receives an RRC message containing conditional switching configuration information, a first candidate cell that satisfies the execution conditions of the conditional switching is determined, and when the terminal device successfully accesses the first candidate cell, the first information includes one or more of the following: identification information of the first candidate cell, index information corresponding to the first candidate cell, signal quality corresponding to the first candidate cell when the terminal device successfully accesses the first candidate cell, a success reason value, indication information that the first candidate cell satisfies the execution conditions of the conditional switching and access is successful, or, signal quality corresponding to some or all of the candidate cells other than the first candidate cell in the at least one candidate cell when the terminal device successfully accesses the first candidate cell; wherein the first network device is a network device to which the first candidate cell belongs, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0014] Based on the above scheme, the terminal device can report the relevant information in the recorded conditional switching process to the first network device, so that the first network device or other network devices can adjust the switching parameters (such as traditional switching configuration information or conditional switching configuration information) according to the relevant information obtained, thereby improving the system reliability and robustness.

[0015] In a possible implementation method, before receiving the first indication information from the first network device, the method further includes: receiving indication information for instructing to record the first information. The indication information may be called second indication information. The second indication information may come from the second network device.

[0016] In a possible implementation method, before receiving the first indication information from the first network device, the method further includes: sending indication information to the first network device indicating that the recording of the first information has been completed. The indication information may be referred to as third indication information. The third indication information may be sent to the first network device.

[0017] Optionally, the second indication information may be included in an RRC reconfiguration message (the RRC reconfiguration message may be an RRC message including CHO configuration information, or an RRC message for traditional switching (i.e., a switching message)). The UE may include the relevant information recorded in the corresponding scenario (i.e., part or all of the first information) in an RRC reconfiguration completion message sent to a network device to which the first cell successfully accessed belongs. Optionally, the third indication information may also be included in an RRC reconfiguration completion message.

[0018] In a third aspect, the present application provides a communication method, comprising: receiving first indication information from a first network device, the first indication information being used to request a terminal device to report first information; reporting the first information to the first network device; wherein, when a wireless link failure, or a traditional switching failure occurs in a source cell of the terminal device, or the terminal device fails to access a first candidate cell that meets the execution conditions of the conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information includes one or more of the following: identification information of the first cell, index information corresponding to the first cell, conditional switching configuration information corresponding to the first cell, signal quality corresponding to the first cell when the terminal device fails to access the first cell, a failure reason value, or indication information that the first cell meets the cell selection criteria and access fails; wherein the first network device is a network device to which the re-established cell belongs, or a network device to which a cell during the RRC establishment process belongs, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0019] Based on the above scheme, the terminal device can report the relevant information in the recorded conditional switching process to the first network device, so that the first network device or other network devices can adjust the switching parameters (such as traditional switching configuration information or conditional switching configuration information) according to the relevant information obtained, thereby improving the system reliability and robustness.

[0020] In a possible implementation method, before receiving the first indication information from the first network device, the method further includes: receiving indication information for indicating recording of the first information. The indication information may be referred to as second indication information. The second indication information may come from the second network device. In a possible implementation method, before receiving the first indication information from the first network device, the method further includes: sending indication information to the first network device for indicating that recording of the first information has been completed. The indication information may be referred to as third indication information. The third indication information may be sent to the first network device.

[0021] Optionally, the second indication information may be included in an RRC reconfiguration message (the RRC reconfiguration message may be an RRC message including CHO configuration information, or an RRC message for traditional switching (i.e., a switching message)). If the reestablishment is successful, the first network device may be a network device to which the reestablished cell belongs, and the UE may include the relevant information recorded in the corresponding scenario (i.e., part or all of the first information) in an RRC reestablishment completion message sent to the network device to which the reestablished cell belongs. Optionally, the RRC reestablishment completion message may also include third indication information. If the reestablishment fails, the first network device may be a network device to which the cell in the RRC establishment process belongs, and the UE may include the relevant information recorded in the corresponding scenario (i.e., part or all of the first information) in an RRC establishment completion message sent to the network device to which the cell in the RRC establishment process belongs. Optionally, the RRC establishment completion message may also include third indication information.

[0022] In a fourth aspect, the present application provides a communication method, comprising: receiving first indication information from a first network device, the first indication information being used to request a terminal device to report first information; reporting the first information to the first network device; wherein, in the case where a wireless link failure occurs in a source cell of the terminal device, or a traditional switching failure, or the terminal device fails to access a first candidate cell that meets the execution conditions of the conditional switching, and the cell selected after cell selection does not belong to at least one candidate cell, the first information includes one or more of the following: cell identification information of the re-established cell, signal quality corresponding to the re-established cell when executing the re-establishment process, a re-establishment reason value, indication information that the cell selected by the terminal device after cell selection meets the cell selection criteria but does not belong to at least one candidate cell, or signal quality corresponding to some or all of the candidate cells in at least one candidate cell when the terminal device executes the re-establishment process; wherein the first network device is a network device to which the re-established cell belongs or a network device to which a cell in the RRC establishment process belongs, and the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0023] Based on the above scheme, the terminal device can report the relevant information in the recorded conditional switching process to the first network device, so that the first network device or other network devices can adjust the switching parameters (such as traditional switching configuration information or conditional switching configuration information) according to the relevant information obtained, thereby improving the system reliability and robustness.

[0024] In a possible implementation method, before receiving the first indication information from the first network device, the method further includes: receiving indication information for instructing to record the first information. The indication information may be called second indication information. The second indication information may come from the second network device.

[0025] In a possible implementation method, before receiving the first indication information from the first network device, the method further includes: sending indication information to the first network device indicating that the recording of the first information has been completed. The indication information may be referred to as third indication information. The third indication information may be sent to the first network device.

[0026] Optionally, the second indication information may be included in an RRC reconfiguration message (the RRC reconfiguration message may be an RRC message including CHO configuration information, or an RRC message for traditional switching (i.e., a switching message)). If the reestablishment is successful, the first network device may be a network device to which the reestablished cell belongs, and the UE may include the relevant information recorded in the corresponding scenario (i.e., part or all of the first information) in an RRC reestablishment completion message sent to the network device to which the reestablished cell belongs. Optionally, the RRC reestablishment completion message may also include third indication information. If the reestablishment fails, the first network device may be a network device to which the cell in the RRC establishment process belongs, and the UE may include the relevant information recorded in the corresponding scenario (i.e., part or all of the first information) in an RRC establishment completion message sent to the network device to which the cell in the RRC establishment process belongs. Optionally, the RRC establishment completion message may also include third indication information.

[0027] In a fifth aspect, the present application provides a communication method, comprising: a first network device sends a first indication message to a terminal device, the first indication message being used to request the terminal device to report the first information; the first network device receives the first information from the terminal device; wherein, when a wireless link failure, a traditional switching failure, or a terminal device fails to access a first candidate cell that meets the execution conditions of the conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information includes one or more of the following: identification information of the first cell, index information corresponding to the first cell, signal quality corresponding to the first cell when the terminal device successfully accesses the first cell, a success reason value, or indication information that the first cell meets the cell selection criteria and access is successful; wherein, the first cell belongs to the first network device, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is the network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0028] Based on the above scheme, the terminal device can report the relevant information in the recorded conditional switching process to the first network device, so that the first network device or other network devices can adjust the switching parameters (such as traditional switching configuration information or conditional switching configuration information) according to the relevant information obtained, thereby improving the system reliability and robustness.

[0029] In a possible implementation method, before sending the first indication information to the terminal device, the method further includes: receiving indication information from the terminal device indicating that the recording of the first information has been completed.

[0030] In a sixth aspect, the present application provides a communication method, comprising: a first network device sends a first indication information to a terminal device, the first indication information being used to request the terminal device to report the first information; the first network device receives the first information from the terminal device; wherein, after the terminal device receives an RRC message containing conditional switching configuration information, a first candidate cell that meets the execution conditions of the conditional switching is determined, and when the terminal device successfully accesses the first candidate cell, the first information includes one or more of the following: identification information of the first candidate cell, index information corresponding to the first candidate cell, signal quality corresponding to the first candidate cell when the terminal device successfully accesses the first candidate cell, a success reason value, indication information that the first candidate cell meets the execution conditions of the conditional switching and the access is successful, or, when the terminal device successfully accesses the first candidate cell, signal quality corresponding to some or all of the candidate cells in the at least one candidate cell other than the first candidate cell; wherein, the first network device is a network device to which the first candidate cell belongs, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0031] Based on the above scheme, the terminal device can report the relevant information in the recorded conditional switching process to the first network device, so that the first network device or other network devices can adjust the switching parameters (such as traditional switching configuration information or conditional switching configuration information) according to the relevant information obtained, thereby improving the system reliability and robustness.

[0032] In a possible implementation method, before sending the first indication information to the terminal device, the method further includes: receiving indication information from the terminal device indicating that the recording of the first information has been completed.

[0033] In a seventh aspect, the present application provides a communication method, comprising: a first network device sends a first indication message to a terminal device, the first indication message being used to request the terminal device to report the first information; the first network device receives the first information from the terminal device; wherein, when a wireless link failure or a traditional switching failure occurs in a source cell of the terminal device, or the terminal device fails to access a first candidate cell that meets the execution conditions of the conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information includes one or more of the following: identification information of the first cell, index information corresponding to the first cell, conditional switching configuration information corresponding to the first cell, signal quality corresponding to the first cell when the terminal device fails to access the first cell, a failure reason value, or indication information that the first cell meets the cell selection criteria and access fails; wherein, the first network device is a network device to which the re-established cell belongs, or a network device to which a cell during the RRC establishment process belongs, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0034] Based on the above scheme, the terminal device can report the relevant information in the recorded conditional switching process to the first network device, so that the first network device or other network devices can adjust the switching parameters (such as traditional switching configuration information or conditional switching configuration information) according to the relevant information obtained, thereby improving the system reliability and robustness.

[0035] In a possible implementation method, before sending the first indication information to the terminal device, the method further includes: receiving indication information from the terminal device indicating that the recording of the first information has been completed.

[0036] In an eighth aspect, the present application provides a communication method, comprising: a first network device sends a first indication message to a terminal device, the first indication message being used to request the terminal device to report the first information; the first network device receives the first information from the terminal device; wherein, in the case where a wireless link failure occurs in the source cell of the terminal device, or a traditional switching failure occurs, or the terminal device fails to access the first candidate cell that meets the execution conditions of the conditional switching, and the cell selected after cell selection does not belong to at least one candidate cell, the first information includes one or more of the following: cell identification information of the re-established cell, signal quality corresponding to the re-established cell when executing the re-establishment process, a re-establishment reason value, indication information that the cell selected by the terminal device after cell selection meets the cell selection criteria but does not belong to at least one candidate cell, or signal quality corresponding to some or all of the candidate cells in at least one candidate cell when the terminal device executes the re-establishment process; wherein the first network device is a network device to which the re-established cell belongs or a network device to which the cell in the RRC establishment process belongs, and the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0037] Based on the above scheme, the terminal device can report the relevant information in the recorded conditional switching process to the first network device, so that the first network device or other network devices can adjust the switching parameters (such as traditional switching configuration information or conditional switching configuration information) according to the relevant information obtained, thereby improving the system reliability and robustness.

[0038] In a possible implementation method, before sending the first indication information to the terminal device, the method further includes: receiving indication information from the terminal device indicating that the recording of the first information has been completed.

[0039] Based on the first aspect, or any implementation method of the first aspect, or the fifth aspect, or any implementation method of the fifth aspect, the following implementation method is also provided:

[0040] In a possible implementation method, when a radio link failure or a traditional handover failure occurs in a source cell of the terminal device, or the terminal device fails to access a first candidate cell that meets an execution condition of the conditional handover, and the first cell selected by the terminal device after performing cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0041] When the terminal device determines the first cell, the signal quality corresponding to some or all of the at least one candidate cell, or,

[0042] When the terminal device successfully accesses the first cell, the signal quality corresponding to some or all of the at least one candidate cell except the first cell.

[0043] In a possible implementation method, when the terminal device fails to access the first candidate cell that meets the execution condition of the conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0044] When the execution condition of the conditional switching corresponding to the first candidate cell is met, the signal quality corresponding to some or all of the at least one candidate cell, or

[0045] When the terminal device fails to access the first candidate cell, the signal quality corresponding to some or all of the at least one candidate cell.

[0046] In a possible implementation method, when a radio link failure occurs in a source cell of the terminal device, a first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0047] Time period 1, where time period 1 is the time period from when the terminal device receives the RRC reconfiguration message to when the radio link failure occurs in the source cell,

[0048] Time period 2, where time period 2 is a time period from when a radio link failure occurs in the source cell to when the terminal device determines the first cell,

[0049] time period 3, where the time period 3 is a time period from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell,

[0050] time period 4, where the time period 4 is a time period from when the terminal device successfully accesses the first cell to when the terminal device reports the time period 4, or,

[0051] A time period consisting of any two or more consecutive time periods from the time period 1 to the time period 4.

[0052] In a possible implementation method, when conventional handover fails, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0053] Time period 5, the time period 5 is the time period from when the terminal device receives the RRC reconfiguration message to when the terminal device receives the traditional switching message,

[0054] Time period 6, the time period 6 is the time period from when the terminal device receives the traditional switching message to when the traditional switching fails,

[0055] Time period 7, the time period 7 is a time period from the failure of conventional handover to the determination of the first cell by the terminal device,

[0056] time period 8, where the time period 8 is a time period from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell,

[0057] time period 9, where the time period 9 is the time period from when the terminal device successfully accesses the first cell to when the terminal device reports the time period 9, or,

[0058] A time period consisting of any two or more consecutive time periods from the time period 5 to the time period 9.

[0059] In a possible implementation method, when the terminal device fails to access the first candidate cell that meets the execution condition of the conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0060] Time period 10, the time period 10 is a time period from when the terminal device receives the RRC reconfiguration message to when the terminal device determines the first candidate cell that meets the execution condition of the conditional switching,

[0061] time period 11, the time period 11 is a time period from when the terminal device determines that the first candidate cell satisfies the execution condition of the conditional switching to when the terminal device fails to access the first candidate cell,

[0062] time period 12, the time period 12 being a time period from when the terminal device fails to access the first candidate cell to when the terminal device determines the first cell,

[0063] time period 13, where the time period 13 is a time period from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell.

[0064] time period 14, the time period 14 being the time period from when the terminal device successfully accesses the first cell to when the terminal device reports the time period 14, or,

[0065] A time period consisting of any two or more consecutive time periods from the time period 10 to the time period 14.

[0066] Based on the second aspect, or any implementation method of the second aspect, or the sixth aspect, or any implementation method of the sixth aspect, the following implementation method is also provided:

[0067] In a possible implementation method, after the terminal device receives an RRC message containing conditional switching configuration information, a first candidate cell that meets the execution conditions of conditional switching is determined, and the terminal device successfully accesses the first candidate cell, the first information includes one or more of the following: identification information of the first candidate cell, index information corresponding to the first candidate cell, signal quality corresponding to the first candidate cell when the terminal device successfully accesses the first candidate cell, a success reason value, indication information that the first candidate cell meets the execution conditions of conditional switching and access is successful, or, signal quality corresponding to some or all of the candidate cells other than the first candidate cell in at least one candidate cell when the terminal device successfully accesses the first candidate cell.

[0068] In a possible implementation method, after the terminal device receives an RRC message containing conditional switching configuration information, a first candidate cell that meets the execution conditions of the conditional switching is determined, and when the terminal device successfully accesses the first candidate cell, the first information includes one or more of the following: cell identification information of the source cell, or signal quality corresponding to the source cell.

[0069] In a possible implementation method, after the terminal device receives an RRC message containing conditional switching configuration information, it determines a first candidate cell that meets the execution conditions of conditional switching, and the terminal device successfully accesses the first candidate cell, and the first information includes one or more of the following: the signal quality corresponding to some or all of the at least one candidate cell when the measurement report is reported, the signal quality corresponding to some or all of the at least one candidate cell when the terminal device determines the first candidate cell, the signal quality corresponding to some or all of the at least one candidate cell when the terminal device receives an RRC message containing conditional switching configuration information, or the signal quality corresponding to some or all of the at least one candidate cell when the terminal device sends an RRC reconfiguration completion message to the first candidate cell.

[0070] In a possible implementation method, after the terminal device receives the RRC message including the conditional switching configuration information, a first candidate cell that meets the execution condition of the conditional switching is determined, and when the terminal device successfully accesses the first candidate cell, the first information includes one or more of the following:

[0071] Time period 1, where time period 1 is a time period from receiving an RRC message including conditional handover configuration information to determining a first candidate cell that meets the execution condition of the conditional handover,

[0072] Time period 2, where time period 2 is a time period from when the first candidate cell that satisfies the execution condition of the conditional switching is determined to when the terminal device successfully accesses the first candidate cell,

[0073] Time period 3, where the time period 3 is a time period from when the terminal device successfully accesses the first candidate cell to when the terminal device reports the time period 3, or,

[0074] A time period consisting of any two or more consecutive time periods from the time period 1 to the time period 3.

[0075] Based on the third aspect, or any implementation method of the third aspect, or the seventh aspect, or any implementation method of the seventh aspect, the following implementation method is also provided:

[0076] In a possible implementation method, when a radio link failure occurs in a source cell of the terminal device, or a traditional handover fails, or the terminal device fails to access a first candidate cell that meets an execution condition of the conditional handover, and the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0077] When the terminal device determines the first cell, the signal quality corresponding to some or all of the at least one candidate cell,

[0078] when the terminal device fails to access the first cell, signal quality corresponding to some or all of the at least one candidate cell except the first cell, or,

[0079] When the terminal device executes the re-establishment process, the signal quality corresponding to some or all of the at least one candidate cell except the first cell.

[0080] In a possible implementation method, when the terminal device fails to access a first candidate cell that meets an execution condition of conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0081] When the execution condition of the conditional switching corresponding to the first candidate cell is met, the signal quality corresponding to some or all of the at least one candidate cell, or

[0082] When the terminal device fails to access the first candidate cell, the signal quality corresponding to some or all of the at least one candidate cell.

[0083] In a possible implementation method, when a radio link failure occurs in a source cell of the terminal device, a first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0084] Time period 1, where time period 1 is the time period from when the terminal device receives the RRC reconfiguration message to when the radio link failure occurs in the source cell,

[0085] Time period 2, where time period 2 is a time period from when a radio link failure occurs in the source cell to when the terminal device determines the first cell,

[0086] time period 3, where the time period 3 is a time period from when the terminal device determines the first cell to when the terminal device fails to access the first cell,

[0087] Time period 4, the time period 4 is a time period from when the terminal device fails to access the first cell to when the terminal device determines to re-establish the cell,

[0088] time period 5, the time period 5 being the time period from when the terminal device determines to re-establish the cell to when the terminal device reports the time period 5, or,

[0089] A time period consisting of any two or more consecutive time periods from the time period 1 to the time period 5.

[0090] In a possible implementation method, when conventional handover fails, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0091] Time period 6, the time period 6 is the time period from when the terminal device receives the RRC reconfiguration message to when the terminal device receives the traditional switching message,

[0092] Time period 7, the time period 7 is the time period from when the terminal device receives the traditional switching message to when the traditional switching fails,

[0093] Time period 8, the time period 8 is a time period from the failure of the traditional handover to the determination of the first cell by the terminal device,

[0094] time period 9, where the time period 9 is a time period from when the terminal device determines the first cell to when the terminal device fails to access the first cell,

[0095] Time period 10, the time period 10 is a time period from when the terminal device fails to access the first cell to when the terminal device determines to re-establish the cell,

[0096] time period 11, the time period 11 is a time period from when the terminal device determines to re-establish a cell to when the terminal device reports the time period 11, or,

[0097] A time period consisting of any two or more consecutive time periods from the time period 6 to the time period 11.

[0098] In a possible implementation method, when the terminal device fails to access a first candidate cell that meets an execution condition of conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0099] time period 12, the time period 12 being the time period from when the terminal device receives the RRC reconfiguration message to when the terminal device determines the first candidate cell that satisfies the execution condition of the conditional switching,

[0100] time period 13, the time period 13 is a time period from when the terminal device determines that the first candidate cell satisfies the execution condition of the conditional switching to when the terminal device fails to access the first candidate cell,

[0101] time period 14, the time period 14 being a time period from when the terminal device fails to access the first candidate cell to when the terminal device determines the first cell,

[0102] time period 15, the time period 15 being a time period from when the terminal device determines the first cell to when the terminal device fails to access the first cell,

[0103] time period 16, the time period 16 is a time period from when the terminal device fails to access the first cell to when the terminal device determines to re-establish the cell,

[0104] time period 17, the time period 17 is a time period from when the terminal device determines to re-establish a cell to when the terminal device reports the time period 17, or,

[0105] A time period consisting of any two or more consecutive time periods from the time period 12 to the time period 17.

[0106] Based on the fourth aspect, or any implementation method of the fourth aspect, or the eighth aspect, or any implementation method of the eighth aspect, the following implementation method is also provided:

[0107] In a possible implementation method, when a wireless link failure occurs in the source cell of the terminal device, or a traditional switching fails, or the terminal device fails to access the first candidate cell that meets the execution conditions of the conditional switching, and the cell selected after cell selection does not belong to at least one candidate cell, the first information also includes one or more of the following: cell identification information of the re-established cell, signal quality corresponding to the re-established cell when executing the re-establishment process, a re-establishment reason value, indication information that the cell selected by the terminal device after cell selection meets the cell selection criteria but does not belong to at least one candidate cell, or signal quality corresponding to some or all of the at least one candidate cell when the terminal device executes the re-establishment process.

[0108] In a possible implementation method, when a wireless link failure or a traditional switching failure occurs in a source cell of the terminal device, or the terminal device fails to access a first candidate cell that meets the execution conditions of the conditional switching, and the cell selected after cell selection does not belong to at least one candidate cell, the first information also includes one or more of the following: cell identification information of the source cell, and signal quality corresponding to the source cell.

[0109] In a possible implementation method, in the event that a wireless link failure occurs in a source cell of the terminal device, the first information also includes one or more of the following: a failure cause value, indication information that a wireless link failure occurs in the source cell, or a signal quality corresponding to at least one candidate cell when a wireless link failure occurs in the source cell.

[0110] In a possible implementation method, in the event that traditional switching of the terminal device fails, the first information also includes one or more of the following: cell identification information of the target cell, signal quality corresponding to the target cell, failure reason value, indication information of traditional switching failure, or signal quality corresponding to at least one candidate cell when traditional switching fails.

[0111] In a possible implementation method, when the terminal device fails to access the first candidate cell that meets the execution conditions of conditional switching, and the cell selected after cell selection does not belong to at least one candidate cell, the first information also includes one or more of the following: cell identification information of the first candidate cell, index information corresponding to the first candidate cell, conditional switching configuration information corresponding to the first candidate cell, signal quality corresponding to the first candidate cell when the terminal device fails to access or switch to the first candidate cell, failure reason value, indication information that the first candidate cell meets the execution conditions of conditional switching but the terminal device fails to access or switch, signal quality corresponding to other candidate cells when the terminal device fails to access or switch to the first candidate cell, signal quality corresponding to the first candidate cell when the execution conditions of conditional switching corresponding to the first candidate cell are met, or signal quality corresponding to other candidate cells when the execution conditions of conditional switching corresponding to the first candidate cell are met.

[0112] In a possible implementation method, when a wireless link failure occurs in the source cell of the terminal device, or a traditional switching fails, or the terminal device fails to access the first candidate cell that meets the execution conditions of the conditional switching, and the cell selected after cell selection does not belong to at least one candidate cell, the first information also includes one or more of the following: the signal quality corresponding to some or all of the at least one candidate cell when the measurement report is reported, the signal quality corresponding to some or all of the at least one candidate cell when the terminal device receives an RRC message containing conditional switching configuration information, the signal quality corresponding to some or all of the at least one candidate cell when RRC re-establishment fails, the signal quality corresponding to some or all of the at least one candidate cell when the RRC establishment process is successful, or the signal quality corresponding to some or all of the at least one candidate cell when RRC re-establishment is successful.

[0113] In a possible implementation method, when a radio link failure occurs in a source cell of the terminal device, the first information further includes one or more of the following:

[0114] Time period 1, where time period 1 is the time period from when the terminal device receives the RRC reconfiguration message to when the radio link failure occurs in the source cell,

[0115] Time period 2, where time period 2 is a time period from when a radio link failure occurs in the source cell to when the terminal device determines a second cell,

[0116] Time period 3, where time period 3 is a time period from when the terminal device determines the second cell to when the terminal device reports time period 3, or,

[0117] A time period consisting of any two or more consecutive time periods from the time period 1 to the time period 3.

[0118] In a possible implementation method, when the conventional handover of the terminal device fails, the first information further includes one or more of the following:

[0119] Time period 4, the time period 4 is the time period from when the terminal device receives the RRC reconfiguration message to when the terminal device receives the traditional switching message,

[0120] Time period 5, the time period 6 is the time period from when the terminal device receives the traditional switching message to when the traditional switching fails,

[0121] Time period 6, where time period 6 is the time period from the failure of the traditional handover to the determination of the second cell by the terminal device,

[0122] Time period 7, the time period 7 is the time period from when the terminal device determines the second cell to when the terminal device reports the time period 7, or the time period consisting of any two or more consecutive time periods from the time period 4 to the time period 7

[0123] In a possible implementation method, when the terminal device fails to access the first candidate cell that meets the execution condition of the conditional switching, and the cell selected after the cell selection does not belong to the at least one candidate cell, the first information further includes one or more of the following:

[0124] Time period 8, where time period 8 is a time period from when the terminal device receives the RRC reconfiguration message to when the terminal device determines that the first candidate cell satisfies the execution condition of the conditional switching.

[0125] Time period 9, where time period 9 is a time period from when the terminal device determines that the first candidate cell satisfies the execution condition of the conditional switching to when the terminal device fails to switch or access the first candidate cell,

[0126] Time period 10, where time period 10 is a time period from when the terminal device fails to switch to or access the first candidate cell to when the terminal device determines the second cell,

[0127] time period 11, where the time period 11 is a time period from when the terminal device determines the second cell to when the terminal device reports the time period 11, or,

[0128] A time period consisting of any two or more consecutive time periods from the time period 8 to the time period 11.

[0129] In a ninth aspect, the present application provides a communication device, which may be a terminal device or a chip for a terminal device. The device has the function of implementing any of the embodiments of the first to fourth aspects and the first to fourth aspects above. The function may be implemented by hardware or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions.

[0130] In a tenth aspect, the present application provides a communication device, which may be a network device or a chip for a network device. The device has the function of implementing any of the embodiments of the fifth to eighth aspects and the fifth to eighth aspects above. The function may be implemented by hardware or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions.

[0131] In the eleventh aspect, the present application provides a communication device, comprising a processor and a memory; the memory is used to store computer-executable instructions, and when the device is running, the processor executes the computer-executable instructions stored in the memory to enable the device to perform the method of the functions of any embodiment of the first to eighth aspects and the embodiments of the first to eighth aspects mentioned above.

[0132] In a twelfth aspect, the present application provides a communication device, comprising a unit or means for executing each step of any embodiment of the first to eighth aspects and each embodiment of the first to eighth aspects.

[0133] In a thirteenth aspect, the present application provides a communication device, including a processor and an interface circuit, wherein the processor is used to communicate with other devices through the interface circuit and execute the method of any embodiment in the first to eighth aspects and the first to eighth aspects. The processor includes one or more.

[0134] In a fourteenth aspect, the present application provides a communication device, including a processor, which is connected to a memory and is used to call a program stored in the memory to execute the method of any embodiment of the first to eighth aspects and the first to eighth aspects. The memory can be located inside the device or outside the device. And the processor includes one or more.

[0135] In the fifteenth aspect, the present application also provides a computer-readable storage medium, which stores instructions. When the computer-readable storage medium is run on a computer, the processor executes the method described in any embodiment of the first to eighth aspects and the embodiments of the first to eighth aspects.

[0136] In the sixteenth aspect, the present application also provides a computer program product comprising instructions, which, when executed on a computer, enables the computer to execute the method described in any of the embodiments of the first to eighth aspects and the first to eighth aspects.

[0137] In the seventeenth aspect, the present application also provides a chip system, comprising: a processor, used to execute the method described in any embodiment of the first to eighth aspects and the embodiments of the first to eighth aspects above.

[0138] In an eighteenth aspect, the present application further provides a communication system, including: a first network device and a terminal device;

[0139] The first network device is used to send first indication information to the terminal device, where the first indication information is used to request the terminal device to report first information;

[0140] The terminal device is used to report the first information to the first network device;

[0141] Wherein, when a radio link failure or a traditional handover failure occurs in a source cell of the terminal device, or the terminal device fails to access a first candidate cell that meets the execution condition of the conditional handover, and the first cell selected by the terminal device after performing cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information includes one or more of the following:

[0142] The identification information of the first cell, the index information corresponding to the first cell, the signal quality corresponding to the first cell when the terminal device successfully accesses the first cell, the success reason value, or the indication information that the first cell meets the cell selection criteria and the access is successful;

[0143] The first cell belongs to the first network device, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is the network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0144] In a nineteenth aspect, the present application further provides a communication system, including: a first network device and a terminal device;

[0145] The first network device is used to send first indication information to the terminal device, where the first indication information is used to request the terminal device to report first information;

[0146] The terminal device is used to report the first information to the first network device;

[0147] Among them, after the terminal device receives the RRC message including the conditional switching configuration information, a first candidate cell that meets the execution condition of the conditional switching is determined, and the terminal device successfully accesses the first candidate cell, the first information includes one or more of the following:

[0148] identification information of the first candidate cell, index information corresponding to the first candidate cell, signal quality corresponding to the first candidate cell when the terminal device successfully accesses the first candidate cell, a success reason value, indication information that the first candidate cell meets the execution conditions of conditional switching and access is successful, or signal quality corresponding to some or all of the candidate cells other than the first candidate cell in the at least one candidate cell when the terminal device successfully accesses the first candidate cell;

[0149] The first network device is a network device to which the first candidate cell belongs, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0150] In a twentieth aspect, the present application further provides a communication system, including: a first network device and a terminal device;

[0151] The first network device is used to send first indication information to the terminal device, where the first indication information is used to request the terminal device to report first information;

[0152] The terminal device is used to report the first information to the first network device;

[0153] Wherein, in the case where a radio link failure occurs in a source cell of the terminal device, or a traditional handover fails, or the terminal device fails to access a first candidate cell that meets the execution condition of the conditional handover, and the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information includes one or more of the following:

[0154] The identification information of the first cell, the index information corresponding to the first cell, the conditional switching configuration information corresponding to the first cell, the signal quality corresponding to the first cell when the terminal device fails to access the first cell, the failure reason value, or the indication information that the first cell meets the cell selection criteria and the access fails;

[0155] The first cell belongs to the first network device, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is the network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0156] In a twenty-first aspect, the present application further provides a communication system, including: a first network device and a terminal device;

[0157] The first network device is used to send first indication information to the terminal device, where the first indication information is used to request the terminal device to report first information;

[0158] The terminal device is used to report the first information to the first network device;

[0159] Among them, when a radio link failure occurs in the source cell of the terminal device, or a traditional handover fails, or the terminal device fails to access the first candidate cell that meets the execution condition of the conditional handover, and the cell selected after the cell selection does not belong to at least one candidate cell, the first information includes one or more of the following:

[0160] cell identification information of the re-established cell, signal quality corresponding to the re-established cell when executing the re-establishment process, re-establishment reason value, indication information that the cell selected by the terminal device after cell selection meets the cell selection criteria but does not belong to at least one candidate cell, or signal quality corresponding to some or all of the at least one candidate cell when the terminal device executes the re-establishment process;

[0161] The first network device is a network device to which the re-established cell belongs or a network device to which the cell in the RRC establishment process belongs, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0162] Figure 1 A schematic diagram of a network architecture applicable to this application;

[0163] Figure 2 A flow chart of a communication method provided by this application;

[0164] Figure 3 A schematic diagram of a communication device provided for this application;

[0165] Figure 4 A schematic diagram of another communication device provided by the present application;

[0166] Figure 5 A schematic diagram of a terminal device provided for this application;

[0167] Figure 6 A schematic diagram of a network device provided for this application. DETAILED DESCRIPTION

[0168] In order to make the purpose, technical solution and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings. The specific operation method in the method embodiment can also be applied to the device embodiment or the system embodiment. In the description of the present application, unless otherwise specified, "multiple" means two or more. Figure 1 FIG. 1 is a schematic diagram of a network architecture applicable to the present application, including a terminal device and a network device. The terminal device communicates with the network device via a wireless interface.

[0169] The terminal device may be a wireless terminal device capable of receiving network device scheduling and indication information. The wireless terminal device may be a device that provides voice and / or data connectivity to a user, or a handheld device with wireless connection function, or other processing device connected to a wireless modem. The wireless terminal device may communicate with one or more core networks or the Internet via a radio access network (e.g., radio access network, RAN). The wireless terminal device may be a mobile terminal device, such as a mobile phone (or "cellular" phone, mobile phone), a computer and a data card. For example, it may be a portable, pocket-sized, handheld, computer-built-in or vehicle-mounted mobile device that exchanges language and / or data with a radio access network. For example, personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), tablet computers (Pads), computers with wireless transceiver functions, and other devices. The wireless terminal device may also be referred to as a system, a subscriber unit, a subscriber station, a mobile station, a mobile station (MS), a remote station (remotestation), an access point (AP), a remote terminal device (remote terminal), an access terminal device (access terminal), a user terminal device (user terminal), a user agent, a subscriber station (SS), a customer premises equipment (CPE), a terminal (terminal), a user equipment (UE), a mobile terminal (MT), etc. The terminal device may also be a wearable device and a next-generation communication system, for example, a terminal device in a 5G network or a terminal device in a future evolved public land mobile network (PLMN) network, a terminal device in an NR communication system, etc. For ease of explanation, the terminal device is UE as an example in the embodiments of the present application.

[0170] A network device is an entity on the network side that is used to transmit or receive signals, such as a new generation Node B (gNodeB). A network device can be a device used to communicate with a mobile device. A network device can be an AP in a wireless local area network (WLAN), an evolutionary Node B (eNB or eNodeB) in long term evolution (LTE), or a relay station or access point, or a vehicle-mounted device, wearable device, or a network device in a future 5G network or a network device in a future evolved public land mobile network (PLMN) network, or a gNodeB in an NR system, etc. In addition, in an embodiment of the present application, the network device provides services for a cell, and the terminal device communicates with the network device through the transmission resources (e.g., frequency domain resources, or spectrum resources) used by the cell. The cell may be a cell corresponding to the network device (e.g., a base station), and the cell may belong to a macro base station or a base station corresponding to a small cell. The small cell here may include: a metro cell, a micro cell, a pico cell, a femto cell, etc. These small cells have the characteristics of small coverage and low transmission power, and are suitable for providing high-speed data transmission services. In addition, in other possible cases, the network device may be other devices that provide wireless communication functions for the terminal device. The embodiments of the present application do not limit the specific technology and specific device form adopted by the network device. For the convenience of description, in the embodiments of the present application, the devices that provide wireless communication functions for the terminal device are collectively referred to as network devices.

[0171] To facilitate understanding of the present application, the relevant technologies are first introduced below.

[0172] 1. Traditional switching mechanism

[0173] In a mobile communication system, in a traditional handover process, the mobility management of a connected UE is controlled by a network device, that is, the network device instructs the UE to switch by sending a handover message to the UE. Specifically, the source base station sends a handover message to the UE to control the UE to switch from the source cell to the target cell. It can be understood that traditional handover refers to the network device to which the source cell belongs sending the configuration information of the target cell to the UE, so that the UE attempts to access or switch to the target cell according to the configuration information.

[0174] The above-mentioned handover message may be a radio resource control (RRC) message. For example, in the NR system, the RRC message may be an RRC reconfiguration message carrying a synchronization reconfiguration information element (reconfiguration with sync). For another example, in the long term evolution (LTE) system, the RRC message may be an RRC connection reconfiguration message carrying a mobility control information element (mobility control info). The handover message includes relevant information of the target cell and relevant configuration parameters required for the UE to access the target cell. For example, the handover message may include the physical cell identifier (PCI) of the target cell, the frequency information corresponding to the target cell, the cell radio network temporary identifier (C-RNTI) allocated by the target cell to the UE, and the random access channel (RACH) resource information required to access the target cell (such as dedicated RACH resources and / or public RACH resources). After receiving the handover message, the UE accesses the target cell according to the content contained in the handover message. Therefore, the successful sending of the handover message is a necessary condition to ensure successful handover under the traditional handover mechanism. However, in LTE systems or NR systems, rapid attenuation of channel quality, rapid movement of UE and obstruction by objects, or long duration of measurement and switching preparation may lead to failure in sending switching messages, resulting in switching failure and reducing the switching success rate.

[0175] 2. Conditional Handover (CHO) Mechanism

[0176] In view of the above-mentioned problems existing in traditional switching, a CHO mechanism is proposed to improve the success rate and robustness of switching. In CHO, the network can configure one or more candidate cells for the UE. Specifically, if the network configures multiple candidate cells for the UE, the network can send the CHO configuration information corresponding to the multiple candidate cells to the UE through one RRC message or multiple RRC messages. The above-mentioned RRC message may be a newly defined message (such as CondRRCReconfiguration, or other naming / expression forms, which are not limited to this) or reuse an existing RRC message (for example, reuse an RRC reconfiguration message, specifically, for example, the RRC message may be an RRC reconfiguration message, or the RRC message may also be an RRC connection reconfiguration message). It can be understood that conditional switching refers to the network device to which the source cell belongs sending configuration information of at least one candidate cell to the UE, and the UE determines the target cell based on the configuration information, and attempts to access or switch to the target cell, wherein the target cell belongs to the at least one candidate cell.

[0177] For example, when the source link signal quality is good, the source base station sends the RRC message to the UE, and the RRC message may include CHO configuration information corresponding to each candidate cell. Specifically, the CHO configuration information may include CHO triggering condition (or execution condition) information and relevant information of the candidate cell.

[0178] The relevant information of the candidate cell may include one or more of the following:

[0179] 1) The C-RNTI allocated by the candidate cell to the UE;

[0180] 2) RACH resource information required to access the candidate cell;

[0181] 3) Index information corresponding to the candidate cell, which is used to identify the candidate cell. Specifically, the index information may be a measurement identifier measID corresponding to the cell and / or a CHO configuration identifier CHO-ConfigId corresponding to the cell, or other forms of expression, which are not limited in this implementation;

[0182] 4) Cell Global Identification (CGI) of the candidate cell, or Evolved Cell Global Identifier (ECGI) of the candidate cell;

[0183] 5), PCI of the candidate cell;

[0184] 6), the frequency information corresponding to the candidate cell may specifically include one or more of the following: the absolute frequency of the synchronization signal block (Synchronization Signal Block, SSB) (such as absoluteFrequencySSB), the absolute frequency position of the reference resource block (such as common resource block 0common RB0) (such as absoluteFrequencyPointA), the frequency bandwidth list (such as frequencyBandList), or the subcarrier spacing SCS specific carrier list (such as scs-SpecificCarrierList);

[0185] 7), physical layer configuration parameters corresponding to the candidate cells;

[0186] 8) medium access control (MAC) layer configuration parameters corresponding to the candidate cell;

[0187] 9), Radio Link Control (RLC) layer configuration parameters corresponding to the candidate cell;

[0188] 10), Packet Data Convergence Protocol (PDCP) layer configuration parameters corresponding to the candidate cell;

[0189] 11), Service Data Adaptation Protocol (SDAP) layer configuration parameters corresponding to the candidate cell;

[0190] 12), RRC layer configuration parameters corresponding to the candidate cells, etc.

[0191] Among them, the CHO trigger condition (or execution condition) information may include the CHO execution event type and the corresponding threshold value. The CHO execution event type may include A1 event, A2 event, A3 event, A4 event, A5 event, B1 event, B2 event or other execution event types. Specifically, A1 event: the signal quality of the serving cell is better than a certain threshold; A2 event: the signal quality of the serving cell is worse than a certain threshold; A3 event: the signal quality of the neighboring cell is higher than a certain threshold than the signal quality of the special cell SpCell (the special cell may include the primary cell PCell or the primary and secondary cells PSCell); A4 event: the signal quality of the neighboring cell is better than a certain threshold; A5 event: the signal quality of the special cell is lower than a certain threshold 1, and the signal quality of the neighboring cell is higher than a certain threshold 2; B1 event: the signal quality of the cross-RAT (Radio Access Technology) neighboring cell is better than a certain threshold; B2 event: the signal quality of the PCell is lower than the threshold 3, and the signal quality of the cross-RAT neighboring cell is higher than the threshold 4.

[0192] For example, a candidate cell may be configured with one or more CHO execution conditions, for example, a candidate cell may be configured with an execution event type, but may be configured with at least one threshold value and / or at most two different trigger quantities, which may include, for example, reference signal receiving power (RSRP), reference signal receiving quality (RSRQ), and signal to interference plus noise ratio (SINR). For another example, a candidate cell may also be configured with at least one execution event type and a threshold value corresponding to each execution event type. The CHO execution event types and / or threshold values ​​corresponding to the execution event types corresponding to different candidate cells may be the same or different, without limitation.

[0193] After receiving the above RRC message, the UE determines whether the candidate cell meets the execution condition of CHO according to the RRC message, and takes the candidate cell that meets the execution condition of CHO as the target cell. Specifically, the UE determines whether the execution condition of CHO is met according to the CHO configuration information. As an example, for candidate cell A, the configured CHO execution event type is A3 event, and the configured corresponding threshold value is the first threshold value (it should be noted that, corresponding to different trigger quantities, the first threshold value may be the same or different), then, when the cell signal quality of candidate cell A (the signal quality includes one or more of RSRP, RSRQ, and SINR, for example, the signal quality includes RSRP and RSRQ, or the signal quality includes RSRP and SINR, or others, which are not limited to this) is higher than the cell signal quality of the serving cell by the first threshold value, it can be considered that candidate cell A meets the execution condition of CHO, and the candidate cell A can be determined as the target cell. As another example, for candidate cell B, an A3 event is configured, and two trigger quantities are configured, for example, RSRP and RSRQ, and the first threshold corresponding to RSRP is configured as E, and the first threshold corresponding to RSRQ is configured as F. Then, when the RSRP of candidate cell A is higher than the RSRP of the serving cell by E, and the RSRQ of candidate cell A is higher than the RSRQ of the serving cell by F, it can be considered that candidate cell A meets the execution conditions of CHO, and the candidate cell A can be determined as the target cell. As another example, for candidate cell B, if the configured CHO execution event type is an A5 event, and the corresponding threshold values ​​configured are the second threshold and the third threshold, then when the cell signal quality of candidate cell B is higher than the second threshold, and the cell signal quality of the serving cell is lower than the third threshold, it can be considered that candidate cell B meets the execution conditions of CHO, and the candidate cell B can be determined as the target cell.

[0194] Regarding the CHO mechanism, there may be several situations, which are explained below.

[0195] Scenario 1: After the UE determines a target cell that meets the execution conditions of CHO among at least one candidate cell (the target cell may be referred to as the first candidate cell) (in the existing CHO mechanism, after the UE determines a target cell that meets the execution conditions of CHO for the first time based on the CHO configuration information, it no longer determines whether other candidate cells meet the execution conditions of CHO), timer T1 is started (T1 may be predefined by the protocol, or the RRC message containing the CHO configuration information contains relevant information of timer T1, such as the effective duration of T1), and the UE attempts to access or switch to the determined target cell, for example, the UE performs a random access process with the determined target cell.

[0196] This scenario 1 also includes scenario 1.1 or scenario 1.2.

[0197] In case 1.1, if the random access is successfully completed within the effective period of T1, the UE sends an RRC message (such as an RRC reconfiguration completion message) to the network device to which the target cell belongs, notifying the network device that the conditional handover is completed.

[0198] In case 1.2, if T1 times out and the UE fails to successfully access the target cell, the UE performs cell selection (e.g., selects a cell that meets the S criterion). The cell selection is further divided into the following cases 1.2.1 or 1.2.2:

[0199] In case 1.2.1, if the selected cell is one of at least one candidate cell, the UE attempts to switch to the cell (the cell may be referred to as the first cell), for example, the UE performs a random access procedure with the first cell.

[0200] Among them, the situation 1.2.1 can be further divided into the following situation 1.2.1.1 or situation 1.2.1.2.

[0201] In case 1.2.1.1, if the access or handover between the UE and the first cell is successful, the CHO process is considered successful.

[0202] Scenario 1.2.1.2: If access or handover between the UE and the first cell is unsuccessful, the UE performs a re-establishment procedure.

[0203] Case 1.2.2: If the selected cell does not belong to at least one candidate cell, the UE performs a re-establishment procedure.

[0204] Optionally, after the UE determines the target cell (i.e., the first candidate cell) that meets the execution conditions of CHO, the random access process can be skipped, that is, the random access process is not performed. That is, after the UE determines the target cell, it may not perform the random access process, but send an RRC reconfiguration completion message to the target network device (for example, if the above RRC message containing the CHO configuration information contains relevant information of RACH-less HO, such as TA information, UL grant information, etc., wherein the relevant information of RACH-less HO corresponds to at least one candidate cell, then the UE may not perform a random access process with the determined target cell).

[0205] Scenario 2: Before the UE determines a target cell that meets the execution conditions of CHO among at least one candidate cell according to the CHO configuration information (the target cell can be referred to as the first candidate cell), or after the UE determines the target cell (i.e., the first candidate cell) but before successfully switching to the target cell, a radio link failure (RLF) occurs in the source cell, the UE performs cell selection (such as selecting a cell that meets the S criterion, where the S criterion can be the S criterion in the existing cell selection or the S criterion in the subsequent cell selection, which is not limited here).

[0206] Cell selection is divided into the following scenario 2.1 or scenario 2.2:

[0207] In case 2.1, if the selected cell is one of at least one candidate cell, the UE attempts to switch to the cell (the cell may be referred to as the first cell, for example, the UE performs a random access procedure with the cell), and the case 2.1 may include the following case 2.1.1 or case 2.1.2:

[0208] Scenario 2.1.1: If the UE successfully accesses or switches to the first cell, the CHO process is considered successful;

[0209] For example, if the UE successfully performs random access to the first cell, then the access or handover between the UE and the first cell is successful. Further, in the NR system, the UE may send an RRC reconfiguration completion message to the first cell; in the LTE system, the UE may send an RRC connection reconfiguration completion message to the first cell.

[0210] In case 2.1.2, if the access or handover between the UE and the cell (ie, the first cell) is unsuccessful, the UE performs a re-establishment procedure.

[0211] In case 2.2, if the selected cell does not belong to at least one candidate cell, the UE performs a re-establishment procedure.

[0212] Scenario 3: In the CHO mechanism, the source network device may maintain the RRC connection / data transmission with the UE until the UE successfully switches to the target cell (the target cell may be referred to as the first candidate cell) that satisfies the execution conditions of CHO (for example, until the UE sends an RRC reconfiguration complete message or an RRC connection reconfiguration complete message to the successfully accessed target cell). That is, after the network sends an RRC message containing CHO configuration information to the UE for the first time, it may subsequently send another RRC message to the UE, for example, a traditional switching message may be sent to the UE.

[0213] Accordingly, before the UE determines the target cell (i.e., the first candidate cell) that meets the execution conditions of CHO according to the CHO configuration information, if the UE receives a traditional handover message, the UE stops the CHO process (e.g., the UE stops the process of trying to determine the target cell that meets the execution conditions of CHO from at least one candidate cell), and performs the traditional handover process according to the traditional handover message. Alternatively, if the UE receives a traditional handover message after the UE determines the first candidate cell but before successfully switching to the first candidate cell, the UE stops the CHO process (e.g., the UE stops the random access process with the determined first candidate cell), and the UE performs the traditional handover process according to the traditional handover message.

[0214] This scenario 3 also includes scenario 3.1 or scenario 3.2.

[0215] Scenario 3.1: If the traditional handover process fails (for example, within the validity period of T304, the UE fails to successfully access the target cell indicated by the traditional handover message, where relevant information of T304, such as the validity period of T304, is included in the traditional handover message), the UE performs cell selection (such as selecting a cell that meets the S criterion). Cell selection is divided into the following two scenarios (Scenario 3.1.1 or Scenario 3.1.2):

[0216] In case 3.1.1, if the selected cell is one of at least one candidate cell, the UE attempts to switch to the cell (the cell may be referred to as the first cell, for example, the UE performs a random access procedure with the cell), which is divided into the following two cases:

[0217] Scenario 3.1.1.1: If the access or handover between the UE and the cell (i.e., the first cell) is successful, the CHO process is considered successful;

[0218] For example, if the UE successfully performs random access to the first cell, then the access or handover between the UE and the first cell is successful. Further, in the NR system, the UE may send an RRC reconfiguration completion message to the first cell; in the LTE system, the UE may send an RRC connection reconfiguration completion message to the first cell.

[0219] Scenario 3.1.1.2: If the access or handover between the UE and the first cell is unsuccessful, the UE performs a re-establishment procedure.

[0220] In case 3.1.2, if the selected cell does not belong to at least one candidate cell, the UE performs a re-establishment procedure.

[0221] In case 3.2, if the conventional handover procedure is successful, the access or handover between the UE and the target cell included in the handover message is successful.

[0222] 3. MRO Mechanism

[0223] Whether in the traditional switching mechanism or the conditional switching mechanism, the switching parameters (such as the configuration information of the target cell, the configuration information of at least one candidate cell, etc.) are one of the key factors affecting the success rate of the traditional switching and conditional switching. In the traditional switching mechanism, in order to optimize the switching parameters, the MRO mechanism is introduced, that is, the UE reports the relevant information in the traditional switching process, and further, the network device can optimize the switching parameters according to the relevant information reported by the UE. Under the MRO mechanism, in the traditional switching process, the UE generally reports the relevant parameters of the switching process in the following two scenarios:

[0224] 1) The UE fails to receive the handover message and RLF occurs;

[0225] 2) The handover message is received successfully, but the handover to the target cell fails or RLF occurs soon after the handover to the target cell. The handover message includes the configuration information of the target cell, and the specific content is not repeated here.

[0226] Specifically, the existing MRO recording scenarios (mainly for traditional switching processes) include:

[0227] 1) The UE fails to successfully receive the switching message, an RLF occurs, and then the UE successfully reestablishes in the new cell. In this case, the information recorded and reported by the UE to the new cell includes some or all of the following: the failure cause value (i.e., RLF), the source cell information (e.g., the cell identification information of the source cell and the signal quality corresponding to the source cell), the reestablished cell (i.e., the new cell) information (e.g., the cell identification information of the reestablished cell and the signal quality corresponding to the reestablished cell), the time from the occurrence of the RLF to the reporting, etc.; wherein, the reestablished cell may be a target cell or other cell, without limitation.

[0228] 2) The UE successfully receives the handover message, but the handover to the target cell fails, or RLF occurs soon after the handover to the target cell succeeds (for example, the signal quality of the target cell is unstable, and the signal quality of the target cell becomes very poor after the UE switches to the target cell). The UE initiates the re-establishment process, wherein the cell where the UE initiates the re-establishment (which may be referred to as the re-established cell) may be the source cell, the target cell, or other cells, without limitation. In this case, the information recorded and reported by the UE to the new cell includes some or all of the following: the failure cause value (i.e., the handover failure HOF), the information of the source cell (for example, including the cell identification information of the source cell and the signal quality corresponding to the source cell), the information of the target cell (for example, including the cell identification information of the target cell and the signal quality corresponding to the target cell), the information of the re-established cell (for example, including the cell identification information of the re-established cell and the signal quality corresponding to the re-established cell), the time period from the receipt of the handover message to the occurrence of the failure, and the time period from the occurrence of the failure to the reporting, etc.

[0229] Specifically, the information of the above-mentioned cells (such as source cells, target cells, and re-established cells) may include: the cell identifier, and / or the signal quality corresponding to the cell (the signal quality mentioned in the full text of this application may include the cell signal quality and / or the signal quality of at least one beam belonging to the cell, the signal quality includes RSRP and / or RSRQ and / or SINR, and the signal quality may be a measurement result obtained by radio resource management (Radio Resource Management, RRM) measurement based on the synchronization signal block (Synchronization Signal Block, SSB) and / or the channel status information Reference Signal (CSI-RS)); wherein the cell identifier may include at least one of the following: PCI, CGI, ECGI, or the frequency point information corresponding to the cell.

[0230] In one example, the UE sends an indication message to the first network device, where the indication message is used to indicate that the UE has recorded relevant information of the RLF or HOF. The specific content can be referred to above and will not be repeated here. Taking the NR system as an example, for example, the indication information may be included in an RRC establishment completion message, an RRC re-establishment completion message, an RRC recovery completion message, or an RRC reconfiguration completion message sent by the UE to the first network device, without limitation. The first network device sends a request message to the UE (for example, the request message may be a user information request (UEInformationRequest) message), and after receiving the request message sent by the first network device, the UE reports the corresponding information recorded by the UE to the first network device (for example, the UE sends a user information response (UEInformationResponse) message to the first network device, and the UEInformationResponse message may include the corresponding information recorded by the UE, such as relevant information of RLF or HOF). Among them, the first network device may be a network device to which the source cell belongs, or a network device to which the target cell belongs, or a network device to which the re-established cell belongs, or other network devices, and this is not limited. After receiving the information reported by the UE, the first network device may send the information reported by the UE to other network devices. For example, the first network device is a network device to which the source cell belongs, and the network device to which the source cell belongs may send part or all of the information reported by the UE to the network device to which the target cell belongs and / or the network device to which the re-established cell belongs; the network device to which the target cell belongs or the network device to which the re-established cell belongs The network device or the network device to which the source cell belongs adjusts corresponding parameters according to part or all of the received information. For another example, the first network device is the network device to which the target cell belongs, and the network device to which the target cell belongs can send part or all of the information reported by the UE to the network device to which the source cell belongs and / or the network device to which the re-established cell belongs, and optionally, the network device to which the source cell belongs sends part or all of the received information to the network device to which the re-established cell belongs; the network device to which the source cell belongs or the network device to which the target cell belongs or the network device to which the re-established cell belongs adjusts corresponding parameters according to part or all of the received information. For another example, the first network device is the network device to which the re-established cell belongs, and the network device to which the re-established cell belongs can send part or all of the information reported by the UE to the network device to which the source cell belongs and / or the network device to which the target cell belongs, and optionally, the network device to which the source cell belongs sends part or all of the received information to the network device to which the target cell belongs; the network device to which the source cell belongs or the network device to which the target cell belongs or the network device to which the re-established cell belongs adjusts corresponding parameters according to part or all of the received information.

[0231] The above-mentioned mobile robustness optimization mechanism only considers recording and reporting the relevant information generated in the traditional switching mechanism. However, there is currently no corresponding recording and reporting method for the relevant information generated in the above-mentioned conditional switching process. The relevant information generated in the various scenarios mentioned in the above-mentioned situations 1 to 3 also needs to be recorded and reported by the UE, so that the network can adjust and optimize the relevant parameters of the conditional switching mechanism and the traditional switching mechanism based on the relevant information, thereby improving the system reliability.

[0232] It should be noted that, in the embodiment of the present application, the identification information mentioned in any of the following places may be at least one of CGI, ECGI, PCI, and frequency information. The frequency information includes but is not limited to one or more of the following: SSB absolute frequency (absoluteFrequencySSB), PointA absolute frequency (absoluteFrequencyPointA), frequency bandwidth list (frequencyBandList), subcarrier spacing (subcarrier spacing, SCS) specific carrier list (scs-SpecificCarrierList).

[0233] In the embodiment of the present application, the index information mentioned anywhere below may be the measurement identifier (measID) corresponding to the cell, or the CHO-ConfigId corresponding to the cell, or other forms of expression. This implementation does not limit this, and the index information can be used to identify the cell.

[0234] First, the following describes the method for recording relevant information in the CHO process provided by this application. The following describes the method in different scenarios.

[0235] It should be noted that in the following scenarios, when the UE records information, each piece of information may be recorded in the same or different variables or information elements, and this application does not limit this. The premise of the following scenarios is that the UE receives CHO configuration information (which may be carried in an RRC reconfiguration message or an RRC connection reconfiguration message) of at least one candidate cell from a network device to which the source cell belongs (hereinafter referred to as a second network device in this application), wherein the specific content of the CHO configuration information of at least one candidate cell can refer to the above description and will not be repeated here.

[0236] Scenario 1: When RLF occurs in the source cell of the UE, or the traditional handover fails, or the UE fails to access or switch to a candidate cell that meets the execution conditions of CHO (referred to as the first candidate cell), the UE performs cell selection. If the cell selected by the UE belongs to at least one candidate cell (such as the cell is referred to as the first cell), and the UE successfully accesses or switches to the first cell.

[0237] Among them, when RLF occurs in the source cell of the UE, if the cell selected by the UE after cell selection belongs to at least one candidate cell (that is, the cell is the first cell), and the UE successfully accesses or switches to the cell, it corresponds to the above situation 2.1.1.

[0238] When the traditional handover fails, if the cell selected by the UE after cell selection belongs to at least one candidate cell (ie, the cell is the first cell), and the UE successfully accesses or switches to the cell, it corresponds to the above situation 3.1.1.1.

[0239] When the UE fails to access or switch to a candidate cell that meets the execution conditions of CHO (called the first candidate cell), if the cell selected by the UE after cell selection belongs to at least one candidate cell (that is, the cell is the first cell), and the UE successfully accesses or switches to the first cell, it corresponds to the above situation 1.2.1.1.

[0240] In this scenario, the NR system is used as an example to illustrate that the UE may record one or more of the following in the corresponding variable or information element:

[0241] 1) Corresponding relevant information when successfully accessing or switching to the first cell. For example, it may include one or more of the following: identification information of the first cell, index information corresponding to the first cell, signal quality corresponding to the first cell when the UE successfully accesses or switches to the first cell, success reason value (e.g., the reason value is "the first cell meets the cell selection criteria (or meets the S criteria) and the access or switching is successful"), or, indication information that the first cell meets the cell selection criteria (or meets the S criteria) and the access or switching is successful.

[0242] 2) Related information corresponding to the source cell. For example, it may include one or more of the following: cell identification information of the source cell, signal quality corresponding to the source cell. Optionally, when RLF occurs in the source cell, the UE may also record one or more of the following information: failure cause value (e.g., cause value is "RLF occurs in the source cell"), indication information of RLF occurring in the source cell, or signal quality corresponding to at least one candidate cell when RLF occurs in the source cell.

[0243] 3) Optionally, when the traditional handover fails, the UE may also record the relevant information corresponding to the traditional handover failure. For example, it may include one or more of the following: the cell identification information of the target cell (the handover message includes the configuration information of the target cell), the signal quality corresponding to the target cell, the failure reason value (such as the reason value is "HOF" or "T304 timeout"), the indication information of the traditional handover failure (or T304 timeout), or the signal quality corresponding to at least one candidate cell when the traditional handover fails (or T304 timeout).

[0244] 4) Optionally, when the UE fails to access or switch to the above-mentioned first candidate cell, the UE may also record the relevant information corresponding to the failure of the UE to access or switch to the first candidate cell. For example, it may include one or more of the following: cell identification information of the first candidate cell, index information corresponding to the first candidate cell, CHO configuration information corresponding to the first candidate cell, signal quality corresponding to the first candidate cell when the UE fails to access or switch to the first candidate cell, failure reason value (e.g., the reason value is "the execution condition of CHO is met but the UE fails to access or switch"), indication information that the first candidate cell meets the execution condition of CHO but the UE fails to access or switch, signal quality corresponding to other candidate cells (i.e., some or all candidate cells in the candidate cells other than the first candidate cell in the above-mentioned at least one candidate cell) when the UE fails to access or switch to the first candidate cell, signal quality corresponding to the first candidate cell when the execution condition of CHO corresponding to the first candidate cell is met, or, signal quality corresponding to other candidate cells (i.e., some or all candidate cells in the candidate cells other than the first candidate cell in the above-mentioned at least one candidate cell) when the execution condition of CHO corresponding to the first candidate cell is met.

[0245] 5) the signal quality corresponding to some or all of the at least one candidate cell when the measurement report is reported, the signal quality corresponding to some or all of the at least one candidate cell when the UE determines the first cell, the signal quality corresponding to some or all of the at least one candidate cell other than the first cell when the UE successfully accesses the first cell (such as when the RACH with the first cell is successful, specifically, when the UE receives MSG4 (such as a contention conflict resolution message) in a contention-based random access process; or, when the UE receives MSG2 (such as a random access response message) in a non-contention-based random access process), the signal quality corresponding to some or all of the candidate cells in at least one candidate cell when the UE receives an RRC message containing conditional switching configuration information (such as an RRC reconfiguration message or an RRC connection reconfiguration message), or, when the UE sends an RRC reconfiguration completion message to the first cell (in an LTE system, the UE sends an RRC connection reconfiguration completion message to the first cell).

[0246] 6) Time information.

[0247] For example, when RLF occurs in the source cell, the UE may record one or more of the following information:

[0248] Time period 1, where time period 1 is a time period from when the UE receives the RRC reconfiguration message to when a radio link failure occurs in the source cell,

[0249] Time period 2, where time period 2 is a time period from when a radio link failure occurs in the source cell to when the UE determines the first cell,

[0250] Time period 3, where time period 3 is a time period from when the UE determines the first cell to when the UE successfully accesses or switches to the first cell,

[0251] Time period 4, the time period 4 is the time period from when the UE successfully accesses or switches to the first cell to when the UE reports the time period 4. Successful access or switching may be a successful random access or a successful sending of an RRC reconfiguration complete message. In other words, time period 3 may be the time period from when the UE determines that random access between the first cell and the UE and the first cell is successful, or time period 3 may be the time period from when the UE determines that the first cell sends an RRC reconfiguration complete message to when the UE sends the RRC reconfiguration complete message; time period 4 may be the time period from when random access between the UE and the first cell is successful to when the UE reports the time period 4, or time period 4 may be the time period from when the UE sends an RRC reconfiguration complete message to when the UE reports the time period 4.

[0252] A time period is formed by any two or more consecutive time periods from the time period 1 to the time period 4. For example, time period 1 and time period 2 can form a new time period, time period 3 and time period 4 can form a new time period; for another example, time period 2 and time period 3 can form a new time period; for another example, time period 1 to time period 3 can also form a new time period, and examples are not given one by one.

[0253] It should be noted that the moment when the radio link failure occurs in the source cell may be equal to or different from the moment when the UE determines the first cell. When the two moments are equal, time period 2 is "0" or the UE does not need to record time period 2. At this time, time period 1 can be replaced with "the time period 1 is the time period from when the UE receives the RRC reconfiguration message to when the UE determines the first cell", and time period 3 can be replaced with "the time period 3 is the time period from when the radio link failure occurs in the source cell to when the UE successfully accesses or switches to the first cell".

[0254] It should be noted that the above time period 1 to time period 4, or the time period obtained according to time period 1 to time period 4, in a specific implementation, can be: when RLF occurs in the source cell, record one or more of the following time periods: time period 1, time period 2, time period 3, and a time period obtained according to any two or more consecutive time periods from time period 1 to time period 3, for example, can be recorded in the same variable or information element, and the variable or information element can be newly defined or reuse an existing one, such as timeConnFailure or others, without limitation. Upon receiving a request for reporting recorded information sent by a network device (such as Figure 2The first indication information described in the corresponding embodiment, or, Figure 2 The second indication information described in the corresponding embodiment) is recorded, or when the UE needs to report time period 4 (for example, in scenario one, when the UE successfully accesses / switches to the first cell, for example, when the UE sends an RRC reconfiguration completion message to the first cell), the above time period 4 is recorded, and / or the time period composed of time period 3 and time period 4 is recorded, and / or the time period obtained by combining the new time period composed of time period X to time period 3 with time period 4, where X is any value from 1 to 2, for example, it can be recorded in another variable or information element, which can be newly defined or reused, such as timeSinceFailure or others, without limitation.

[0255] For another example, in the event of a traditional failure, the UE may record one or more of the following information:

[0256] Time period 5, the time period 5 is the time period from when the UE receives the RRC reconfiguration message to when the UE receives the traditional handover message,

[0257] Time period 6, where time period 6 is the time period from when the UE receives the traditional handover message to when the traditional handover fails,

[0258] Time period 7, where time period 7 is a time period from when a conventional handover fails to when the UE determines the first cell,

[0259] time period 8, where the time period 8 is a time period from when the UE determines the first cell to when the UE successfully accesses the first cell,

[0260] Time period 9, the time period 9 is the time period from when the UE successfully accesses or switches to the first cell to when the UE reports the time period 9. Successful access or switching may be a successful random access or a successful sending of an RRC reconfiguration complete message. In other words, time period 8 may be the time period for the UE to determine that random access between the first cell and the UE and the first cell is successful, or time period 8 may be the time period for the UE to determine that the first cell sends an RRC reconfiguration complete message to the UE; time period 9 may be the time period from when random access between the UE and the first cell is successful to when the UE reports the time period 9, or time period 9 may be the time period for when the UE sends an RRC reconfiguration complete message to when the UE reports the time period 9. Or,

[0261] A time period consisting of any two or more consecutive time periods from the time period 5 to the time period 9.

[0262] It should be noted that the moment when the traditional handover fails may be equal to or different from the moment when the UE determines the first cell. When the two moments are equal, time period 7 is "0" or the UE does not need to record time period 7. At this time, time period 6 can be replaced by "the time period 6 is the time period from when the UE receives the traditional handover message to when the UE determines the first cell", and time period 8 can be replaced by "the time period 8 is the time period from when the traditional handover fails to when the UE successfully accesses the first cell".

[0263] It should be noted that the above time periods 5 to 9, or the time periods obtained from time periods 5 to 9, in a specific implementation, may be: when a traditional switching failure occurs, one or more of the following time periods are recorded: time period 5, time period 6, time period 7, time period 8, and time periods obtained from any two or more consecutive time periods from time period 5 to time period 8, for example, they may be recorded in the same variable or cell, which may be newly defined or reuse an existing one, such as timeConnFailure or others, without limitation. Upon receiving a request for reporting recorded information sent by a network device (such as Figure 2 The first indication information described in the corresponding embodiment, or, Figure 2 The second indication information described in the corresponding embodiment) is recorded, or when the UE needs to report time period 9 (for example, in scenario one, when the UE successfully accesses / switches to the first cell, for example, when the UE sends an RRC reconfiguration completion message to the first cell), the above time period 9 is recorded, and / or the time period composed of time period 8 and time period 9 is recorded, and / or the time period obtained by combining the new time period composed of time period X to time period 8 with time period 9, where X is any value from 5 to 7, for example, it can be recorded in another variable or information element, which can be newly defined or reused, such as timeSinceFailure or others, without limitation.

[0264] For another example, when the UE fails to access or switch to a candidate cell (i.e., the first candidate cell) that meets the execution conditions of CHO, the UE may record one or more of the following information:

[0265] Time period 10, where time period 10 is a time period from when the UE receives the RRC reconfiguration message to when the UE determines that the first candidate cell satisfies the execution condition of the conditional switching.

[0266] time period 11, where the time period 11 is a time period from when the UE determines that the first candidate cell satisfies the execution condition of the conditional switching to when the UE fails to access the first candidate cell,

[0267] time period 12, where the time period 12 is a time period from when the UE fails to access the first candidate cell to when the UE determines the first cell,

[0268] Time period 13, the time period 13 is a time period from when the UE determines that the first cell is a time period from when the UE successfully accesses or switches to the first cell. Successful access or switching may be a successful random access or a successful sending of an RRC reconfiguration complete message. In other words, the time period 13 may be a time period from when the UE determines that the random access between the first cell and the UE and the first cell is a successful time period, or the time period 13 may be a time period from when the UE determines that the first cell is a time period from when the UE sends an RRC reconfiguration complete message.

[0269] Time period 14, the time period 14 is the time period from when the UE successfully accesses or switches to the first cell to when the UE reports the time period 14. Successful access or switching may be a successful random access or a successful sending of an RRC reconfiguration completion message. That is, time period 14 may be the time period from when the UE successfully accesses the first cell to when the UE reports the time period 14, or time period 14 may be the time period from when the UE sends an RRC reconfiguration completion message to when the UE reports the time period 14. Or,

[0270] A time period consisting of any two or more consecutive time periods from the time period 10 to the time period 14.

[0271] It should be noted that the moment when the UE fails to access the first candidate cell may be equal to or different from the moment when the UE determines the first cell. When the two moments are equal, time period 12 is "0" or the UE does not need to record time period 12. At this time, time period 11 can be replaced with "the time period 11 is the time period from when the UE determines the first candidate cell that meets the execution conditions of the conditional switching to when the UE determines the first cell", and time period 13 can be replaced with "the time period 13 is the time period from when the UE fails to access the first candidate cell to when the UE successfully accesses or switches to the first cell".

[0272] It should be noted that the above time period 10 to time period 14, or the time period obtained according to time period 10 to time period 14, in a specific implementation, can be: when the UE fails to access or switch to a candidate cell that meets the execution conditions of CHO (i.e., the first candidate cell), one or more of the following time periods are recorded: time period 10, time period 11, time period 12, time period 13, and time periods obtained according to any two or more consecutive time periods from time period 10 to time period 13, for example, they can be recorded in the same variable or information element, which can be newly defined or reuse existing ones, such as timeConnFailure or others, without limitation. Upon receiving a request for reporting recorded information sent by a network device (such as Figure 2 The first indication information described in the corresponding embodiment, or, Figure 2 The second indication information described in the corresponding embodiment) is recorded, or when the UE needs to report the time period 14 (for example, in scenario one, when the UE successfully accesses / switches to the first cell, for example, when the UE sends an RRC reconfiguration completion message to the first cell), the above-mentioned time period 14 is recorded, and / or the time period composed of the time period 13 and the time period 14 is recorded, and / or the time period obtained by combining the new time period composed of the time period X to the time period 13 with the time period 14, where X is any value from 10 to 12, for example, it can be recorded in another variable or information element, which can be newly defined or reuse an existing one, such as timeSinceFailure or others, without limitation.

[0273] In this scenario, the UE includes indication information in the RRC reconfiguration completion message sent to the first cell (or the network device to which the first cell belongs), and the indication information is used to indicate that the UE has recorded one or more of the above information 1) to 6).

[0274] Scenario 2: After receiving the RRC message including CHO configuration information, the UE determines a candidate cell (referred to as the first candidate cell) that meets the execution conditions of CHO, and the access or handover between the UE and the first candidate cell is successful.

[0275] This scenario corresponds to situation 1.1 above.

[0276] In the second scenario, taking the NR system as an example, the UE may record one or more of the following in the corresponding variable or information element:

[0277] 1) The relevant information corresponding to the successful access or handover to the first candidate cell may include, for example, one or more of the following: identification information of the first candidate cell, index information corresponding to the first candidate cell, signal quality corresponding to the first candidate cell when the UE successfully accesses or hands over to the first candidate cell, success reason value (e.g., the reason value is "the cell meets the execution conditions of CHO and the access or handover is successful"), indication information that the first candidate cell meets the execution conditions of CHO and the access or handover is successful, or, when the UE successfully accesses or hands over to the first candidate cell (e.g., when the RACH with the first candidate cell is successful, specifically, when the UE receives MSG4 (e.g., contention conflict resolution message) in the contention-based random access process; or when the UE receives MSG2 (e.g., random access response message) in the non-contention-based random access process), the signal quality corresponding to some or all candidate cells in the at least one candidate cell other than the first candidate cell. "When the UE successfully accesses or hands over to the first candidate cell" may be replaced by "when the UE's random access to the first candidate cell is successful".

[0278] 2) Related information corresponding to the source cell: For example, it may include one or more of the following: cell identification information of the source cell, or signal quality corresponding to the source cell.

[0279] 3) the signal quality corresponding to some or all of the at least one candidate cell when the measurement report is reported, the signal quality corresponding to some or all of the at least one candidate cell when the UE determines the first candidate cell, the signal quality corresponding to some or all of the at least one candidate cell when the UE receives an RRC message containing conditional switching configuration information (such as an RRC reconfiguration message or an RRC connection reconfiguration message), or the signal quality corresponding to some or all of the at least one candidate cell when the UE sends an RRC reconfiguration completion message to the first candidate cell (in the LTE system, the UE sends an RRC connection reconfiguration completion message to the first candidate cell).

[0280] 4) Time information. For example, it may include one or more of the following:

[0281] Time period 1, where time period 1 is a time period from receiving an RRC message including CHO configuration information to determining a first candidate cell that meets the execution conditions of CHO,

[0282] Time period 2, where time period 2 is a time period from when the first candidate cell satisfying the execution condition of CHO is determined to when the UE accesses or switches to the first candidate cell successfully.

[0283] Time period 3, the time period 3 is the time period from when the UE successfully accesses or switches to the first candidate cell to when the UE reports the time period 3. Successful access or switching may be a successful random access or a successful sending of an RRC reconfiguration completion message. In other words, time period 2 may be the time period from when the UE determines that random access between the first candidate cell and the UE and the first candidate cell is successful, or time period 2 may be the time period from when the UE determines that the first candidate cell is the time period from when the UE sends an RRC reconfiguration completion message to when the UE reports the time period 3; time period 3 may be the time period from when random access between the UE and the first candidate cell is successful to when the UE reports the time period 3, or time period 3 may be the time period from when the UE sends an RRC reconfiguration completion message to when the UE reports the time period 3. Or,

[0284] A time period consisting of any two or more consecutive time periods from the time period 1 to the time period 3.

[0285] It should be noted that the above time period 1 to time period 3, or the time period obtained from time period 1 to time period 3, in a specific implementation, can be: when RLF occurs in the source cell, record one or more of the following time periods: time period 1, time period 2, and the time period obtained from time period 1 to time period 2, for example, they can be recorded in the same variable or information element, and the variable or information element can be newly defined or reuse existing ones, such as timeConnFailure or others, without limitation. Upon receiving a request for reporting recorded information sent by a network device (such as Figure 2 The first indication information described in the corresponding embodiment, or, Figure 2 The second indication information described in the corresponding embodiment) is recorded, or when the UE needs to report time period 3 (for example, in scenario two, when the UE successfully accesses / switches to the first candidate cell, for example, when the UE sends an RRC reconfiguration completion message to the first candidate cell), the above time period 3 is recorded, and / or the time period composed of time period 2 and time period 3 is recorded, and / or the time period composed of time period 1 to time period 3 is recorded, for example, it can be recorded in another variable or information element, which can be newly defined or reused, such as timeSinceFailure or others, without limitation.

[0286] In the second scenario, the UE includes indication information in the RRC reconfiguration completion message sent to the first candidate cell (or the network device to which the first candidate cell belongs), and the indication information is used to indicate that the UE has recorded one or more of the above information 1)-4).

[0287] Scenario 3: When the source cell of the UE has RLF, or the traditional handover fails, or the UE fails to access or handover with the candidate cell that meets the execution conditions of CHO (called the first candidate cell), if the cell selected by the UE after cell selection belongs to the candidate cell, but the UE fails to access or handover with the cell (called the first cell). When the UE fails to access or handover with the first cell, the UE initiates the RRC re-establishment process, which may succeed or fail. When the re-establishment process fails, the UE enters the idle state and the UE performs the RRC establishment process.

[0288] Among them, when RLF occurs in the source cell of the UE, if the cell selected by the UE after cell selection belongs to the candidate cell (the cell is the first cell), but the UE fails to access or switch to the first cell, it corresponds to the above situation 2.1.2. When the traditional handover fails, if the cell selected by the UE after cell selection belongs to the candidate cell (the cell is the first cell), but the UE fails to access or switch to the first cell, it corresponds to the above situation 3.1.1.2. When the UE fails to access or switch to the candidate cell that meets the execution conditions of CHO (called the first candidate cell), if the cell selected by the UE after cell selection belongs to the candidate cell (the cell is the first cell), but the UE fails to access or switch to the first cell, it corresponds to the above situation 1.2.1.2.

[0289] In this scenario three, taking the NR system as an example, the UE may record one or more of the following in the corresponding variable or information element:

[0290] 1) The relevant information corresponding to the failure of UE to access or switch to the selected first cell may include, for example, one or more of the following: identification information of the first cell, index information corresponding to the first cell, CHO configuration information corresponding to the first cell, signal quality corresponding to the first cell when the UE fails to access or switch to the first cell, a failure cause value (the failure cause value may be newly defined, such as the cause value being "the cell meets the cell selection criteria (or meets the S criteria) but access or switching fails", or reusing an existing cause value, such as "HOF", without limitation), indication information that the cell meets the cell selection criteria (or meets the S criteria) but access or switching fails, or, when the UE fails to access or switch to the first cell, other candidate cells (i.e., some or all of the candidate cells in the at least one candidate cell except the first cell) corresponding to the signal quality.

[0291] 2) For the relevant information corresponding to the source cell, please refer to 2) of the above scenario 1 and will not be repeated here.

[0292] 3) Optionally, when the traditional handover fails, the UE may also record relevant information corresponding to the traditional handover failure, which may refer to 3) of the above scenario 1 and will not be described in detail.

[0293] 4) Optionally, when the UE fails to access or switch to the first candidate cell, the UE may also record relevant information corresponding to the failure to access or switch to the first candidate cell. Please refer to 4) of the above scenario 1, and no further details will be given.

[0294] 5) Corresponding relevant information when initiating the re-establishment process (because the UE initiates the re-establishment process when the access or handover between the UE and the determined first cell fails). For example, it may include one or more of the following: cell identification information of the re-established cell, signal quality corresponding to the re-established cell when executing the re-establishment process, re-establishment cause value (the cause value may be newly defined, such as the cause value is "failure to establish access or handover with a CHO candidate cell that meets the cell selection criteria (or meets the S criteria)", or reuse of an existing cause value, such as "HOF", without limitation), or indication information of the UE's access or handover failure with the first cell that meets the cell selection criteria (or meets the S criteria).

[0295] 6) The signal quality corresponding to some or all of the at least one candidate cell when the measurement report is reported, the signal quality corresponding to some or all of the at least one candidate cell when the UE determines the first cell, the signal quality corresponding to some or all of the at least one candidate cell when the UE initiates the re-establishment process, the signal quality corresponding to some or all of the at least one candidate cell when the UE receives an RRC message containing conditional switching configuration information (such as an RRC reconfiguration message or an RRC connection reconfiguration message), or the signal quality corresponding to some or all of the candidate cells in at least one candidate cell when the re-establishment process is successful.

[0296] 7) Time information.

[0297] For example, when RLF occurs in the source cell, the UE may record one or more of the following information:

[0298] Time period 1, where time period 1 is a time period from when the UE receives the RRC reconfiguration message to when a radio link failure occurs in the source cell,

[0299] Time period 2, where time period 2 is a time period from when the radio link failure occurs in the source cell to when the UE determines the first cell,

[0300] Time period 3, where time period 3 is a time period from when the UE determines the first cell to when the UE fails to access or switch to the first cell,

[0301] Time period 4, where time period 4 is a time period from when the UE fails to access or switch to the first cell to when the UE determines to re-establish the cell,

[0302] Time period 5, the time period 5 is the time period from when the UE determines to re-establish the cell to when the UE reports the time period 5, or,

[0303] A time period composed of any two or more continuous time periods from the time period 1 to the time period 5, for example, time period 1 and time period 2 can constitute a new time period, and time period 1 to time period 3 can also constitute a new time period, and examples are not given one by one.

[0304] It should be noted that the moment when the radio link failure occurs in the source cell may be equal to or different from the moment when the UE determines the first cell. When the two moments are equal, time period 2 is "0" and the UE does not need to record time period 2. At this time, time period 1 can be replaced with "the time period 1 is the time period from when the UE receives the RRC reconfiguration message to when the UE determines the first cell", and time period 3 can be replaced with "the time period 3 is the time period from when the radio link failure occurs in the source cell to when the UE fails to access or switch to the first cell".

[0305] It should be noted that the moment when the UE fails to access or switch to the first cell may be equal to or different from the moment when the UE determines to re-establish the cell. When the two moments are equal, time period 4 is "0" or the UE does not need to record time period 4. At this time, time period 3 can be replaced with "the time period 3 is the time period from when the UE determines the first cell to when the UE determines to re-establish the cell", and time period 5 can be replaced with "the time period 5 is the time period from when the UE fails to access or switch to the first cell to when the UE reports the time period 5".

[0306] It should be noted that the above time periods 1 to 5, or the time periods obtained according to time periods 1 to 5, may be, in a specific implementation, as follows: when RLF occurs in the source cell, one or more of the following time periods are recorded: time period 1, time period 2, time period 3, time period 4, and time periods obtained according to any two or more consecutive time periods from time period 1 to time period 4, for example, they may be recorded in the same variable or information element, which may be newly defined or reuse an existing one, such as timeConnFailure or others, without limitation. Upon receiving a request for reporting recorded information sent by a network device (such as Figure 2 The first indication information described in the corresponding embodiment, or, Figure 2The second indication information described in the corresponding embodiment) is recorded, or when the UE needs to report time period 5 (for example, in scenario three, when the UE re-establishes successfully or the RRC is established successfully, for example, when the UE sends an RRC re-establishment completion message to the re-established cell or when the UE sends an RRC establishment completion message to the cell in the RRC establishment process), the above-mentioned time period 5 is recorded, and / or the time period formed by time period 4 and time period 5 is recorded, and / or the time period obtained by combining the new time period formed by time period X to time period 4 with time period 5, where X is any value from 1 to 3, for example, it can be recorded in another variable or information element, which can be newly defined or reused, such as timeSinceFailure or others, without limitation.

[0307] For another example, in the event of a traditional handover failure, the UE may record one or more of the following information:

[0308] Time period 6, the time period 6 is the time period from when the UE receives the RRC reconfiguration message to when the UE receives the traditional handover message,

[0309] Time period 7, where time period 7 is the time period from when the UE receives the traditional handover message to when the traditional handover fails,

[0310] Time period 8, where time period 8 is a time period from when a conventional handover fails to when the UE determines the first cell,

[0311] time period 9, where the time period 9 is a time period from when the UE determines the first cell to when the UE fails to access or switch to the first cell,

[0312] Time period 10, where time period 10 is a time period from when the UE fails to access or switch to the first cell to when the UE determines to re-establish the cell,

[0313] Time period 11, the time period 11 is the time period from when the UE determines to re-establish the cell to when the UE reports the time period 11. Or,

[0314] A time period consisting of any two or more consecutive time periods from the time period 6 to the time period 11.

[0315] It should be noted that the moment when the traditional handover fails may be equal to or different from the moment when the UE determines the first cell. When the two moments are equal, time period 8 is "0" or the UE does not need to record time period 8. At this time, time period 7 can be replaced by "the time period 7 is the time period from when the UE receives the traditional handover message to when the UE determines the first cell", and time period 9 can be replaced by "the time period 9 is the time period from when the traditional handover fails to when the UE fails to access or switch to the first cell".

[0316] It should be noted that the moment when the UE fails to access or switch to the first cell may be equal to or different from the moment when the UE determines to re-establish the cell. When the two moments are equal, time period 10 is "0" or the UE does not need to record time period 10. At this time, time period 9 can be replaced with "the time period 9 is the time period from when the UE determines the first cell to when the UE determines to re-establish the cell", and time period 10 can be replaced with "the time period 10 is the time period from when the UE fails to access or switch to the first cell to when the UE reports the time period 10".

[0317] It should be noted that the above time period 6 to time period 11, or the time period obtained according to time period 6 to time period 11, in a specific implementation, can be: when a traditional switching failure occurs, record one or more of the following time periods: time period 6, time period 7, time period 8, time period 9, time period 10, and the time period obtained according to any two or more consecutive time periods from time period 6 to time period 10, for example, can be recorded in the same variable or cell, and the variable or cell can be newly defined or reuse existing ones, such as timeConnFailure or others, without limitation. Upon receiving a request for reporting recorded information sent by a network device (such as Figure 2 The first indication information described in the corresponding embodiment, or, Figure 2 The second indication information described in the corresponding embodiment) is recorded, or when the UE needs to report the time period 11 (for example, in scenario three, when the UE re-establishes successfully or the RRC is established successfully, for example, when the UE sends an RRC re-establishment completion message to the re-established cell or when the UE sends an RRC establishment completion message to the cell in the RRC establishment process), the above-mentioned time period 11 is recorded, and / or the time period composed of the time period 10 and the time period 11 is recorded, and / or the time period obtained by combining the new time period composed of the time period X to the time period 10 with the time period 11, where X is any value from 6 to 9, for example, it can be recorded in another variable or information element, which can be newly defined or reused, such as timeSinceFailure or others, without limitation.

[0318] For another example, when the UE fails to access or switch to the first candidate cell that meets the execution condition of CHO, the UE may record one or more of the following information:

[0319] time period 12, the time period 12 being the time period from when the UE receives the RRC reconfiguration message to when the UE determines that the first candidate cell satisfies the execution condition of the conditional switching,

[0320] time period 13, where the time period 13 is a time period from when the UE determines that the first candidate cell satisfies the execution condition of the conditional switching to when the UE fails to access or switch to the first candidate cell,

[0321] time period 14, where the time period 14 is a time period from when the UE fails to access or switch to the first candidate cell to when the UE determines the first cell,

[0322] time period 15, where the time period 15 is a time period from when the UE determines the first cell to when the UE fails to access or switch to the first cell,

[0323] Time period 16, where the time period 16 is a time period from when the UE fails to access or switch to the first cell to when the UE determines to re-establish the cell,

[0324] time period 17, the time period 17 is the time period from when the UE determines to re-establish the cell to when the UE reports the time period 17, or,

[0325] A time period consisting of any two or more consecutive time periods from the time period 12 to the time period 17.

[0326] It should be noted that the moment when the UE fails to access the first candidate cell may be equal to or different from the moment when the UE determines the first cell. When the two moments are equal, time period 14 is "0" or the UE does not need to record time period 14. At this time, time period 13 can be replaced by "the time period 13 is the time period from when the UE determines the first candidate cell that meets the execution conditions of the conditional switching to when the UE determines the first cell", and time period 15 can be replaced by "the time period 15 is the time period from when the UE fails to access the first candidate cell to when the UE fails to access the first cell".

[0327] It should be noted that the moment when the UE fails to access or switch to the first cell may be equal to or different from the moment when the UE determines to re-establish the cell. When the two moments are equal, time period 16 is "0" or the UE does not need to record time period 16. At this time, time period 15 can be replaced with "the time period 15 is the time period from when the UE determines the first cell to when the UE determines to re-establish the cell", and time period 17 can be replaced with "the time period 17 is the time period from when the UE fails to access or switch to the first cell to when the UE reports the time period 17".

[0328] It should be noted that the above time period 12 to time period 17, or the time period obtained according to time period 12 to time period 17, in a specific implementation, can be: when the UE fails to access or switch with the candidate cell (i.e., the first candidate cell) that meets the execution conditions of CHO, one or more of the following time periods are recorded: time period 12, time period 13, time period 14, time period 15, time period 16, and time periods obtained according to any two or more consecutive time periods from time period 12 to time period 16, for example, they can be recorded in the same variable or information element, which can be newly defined or reuse existing ones, such as timeConnFailure or others, without limitation. Upon receiving a request for reporting recorded information sent by a network device (such as Figure 2 The first indication information described in the corresponding embodiment, or, Figure 2 The second indication information described in the corresponding embodiment) is recorded, or when the UE needs to report time period 17 (for example, in scenario three, when the UE re-establishes successfully or the RRC is established successfully, for example, when the UE sends an RRC re-establishment completion message to the re-established cell or when the UE sends an RRC establishment completion message to the cell in the RRC establishment process), the above-mentioned time period 17 is recorded, and / or the time period composed of time period 16 and time period 17 is recorded, and / or the time period obtained by combining the new time period composed of time period X to time period 16 with time period 17, where X is any value from 12 to 15, for example, it can be recorded in another variable or information element, which can be newly defined or reused, such as timeSinceFailure or others, without limitation.

[0329] In this scenario three, if the re-establishment is successful, the UE includes indication information in the RRC re-establishment completion message sent to the re-established cell (or the network device to which the re-established cell belongs), and the indication information is used to indicate that the UE has recorded one or more of the above information 1) to 7); if the re-establishment fails, the UE includes indication information in the RRC establishment completion message sent to the cell in the RRC establishment process (or the network device to which the cell belongs), and the indication information is used to indicate that the UE has recorded one or more of the above information 1) to 7).

[0330] Scenario 4: When RLF occurs in the source cell of the UE, or the traditional handover fails, or the access or handover of the UE to the candidate cell that meets the execution conditions of CHO (called the first candidate cell) fails, if the cell selected by the UE after cell selection does not belong to the candidate cell, then at this time, the UE performs the RRC re-establishment process. Specifically, the UE may succeed in re-establishment or fail in re-establishment. If the re-establishment fails, the UE enters the idle state, and the UE performs the RRC establishment process.

[0331] When RLF occurs in the source cell of the UE, if the cell selected by the UE after cell selection does not belong to the candidate cells, it corresponds to the above situation 2.2.

[0332] When the conventional handover fails, if the cell selected by the UE after performing cell selection does not belong to the candidate cells, it corresponds to the above situation 3.1.2.

[0333] When the UE fails to access or switch to a candidate cell that meets the execution conditions of CHO (referred to as the first candidate cell), if the cell selected by the UE after cell selection (for example, the cell is the second cell) does not belong to the candidate cell, it corresponds to the above situation 1.2.2.

[0334] In this scenario 4, taking the NR system as an example, the UE may record one or more of the following in the corresponding variable or information element:

[0335] 1) The relevant information corresponding to the UE initiating the re-establishment process, for example, may include one or more of the following: cell identification information of the re-established cell (i.e., the cell selected by the UE after performing cell selection), the signal quality corresponding to the re-established cell when executing the re-establishment process, the re-establishment reason value (the reason value may be newly defined, such as the reason value is "the cell selected by the UE after performing cell selection satisfies the cell selection criteria (or satisfies the S criteria) but does not belong to at least one candidate cell", or the existing reason value may be reused without limitation), indication information that the cell selected by the UE after performing cell selection satisfies the cell selection criteria (or satisfies the S criteria) but does not belong to at least one candidate cell, or the signal quality corresponding to some or all of the at least one candidate cell when the UE performs the re-establishment process.

[0336] 2) to 4) can refer to 2) to 4) in the above scenario 3 and will not be repeated here.

[0337] 5) The signal quality corresponding to some or all of the at least one candidate cell when the measurement report is reported, the signal quality corresponding to some or all of the at least one candidate cell when the UE receives an RRC message containing conditional switching configuration information (such as an RRC reconfiguration message or an RRC connection reconfiguration message), the signal quality corresponding to some or all of the at least one candidate cell when RRC re-establishment fails, the signal quality corresponding to some or all of the at least one candidate cell when the RRC establishment process is successful, or the signal quality corresponding to some or all of the at least one candidate cell when the RRC re-establishment is successful.

[0338] 6) Time information.

[0339] For example, when RLF occurs in the source cell, the UE may record one or more of the following information:

[0340] Time period 1, where time period 1 is a time period from when the UE receives the RRC reconfiguration message to when a radio link failure occurs in the source cell,

[0341] Time period 2, the time period 2 is the time period from the occurrence of wireless link failure in the source cell to the UE determining the second cell, wherein "UE determines the second cell" can be replaced by "UE re-establishes", that is, the time period 2 can be the time period from the occurrence of wireless link failure in the source cell to the UE re-establishing.

[0342] Time period 3, the time period 3 is the time period from when the UE determines the second cell to when the UE reports the time period 3, wherein "UE determines the second cell" can be replaced by "UE reestablishes", that is, the time period 3 can be the time period from when the UE reestablishes to when the UE reports the time period 3. Or,

[0343] A time period composed of any two or more continuous time periods from the time period 1 to the time period 3, for example, time period 1 and time period 2 can constitute a new time period, and time period 1 to time period 3 can also constitute a new time period, and examples are not given one by one.

[0344] It should be noted that the moment when the radio link failure occurs in the source cell may be equal to or different from the moment when the UE determines the second cell. When the two moments are equal, time period 2 is "0" or the UE does not need to record time period 2. At this time, time period 1 can be replaced with "the time period 1 is the time period from when the UE receives the RRC reconfiguration message to when the UE determines the second cell", and time period 3 can be replaced with "the time period 3 is the time period from when the radio link failure occurs in the source cell to when the UE reports the time period 3".

[0345] It should be noted that the above time period 1 to time period 3, or the time period obtained according to time period 1 to time period 3, in a specific implementation, can be: when RLF occurs in the source cell, record one or more of the following time periods: time period 1, time period 2, and the time period obtained according to time period 1 and time period 2, for example, can be recorded in the same variable or information element, and the variable or information element can be newly defined or reuse existing ones, such as timeConnFailure or others, without limitation. Upon receiving a request for reporting recorded information sent by a network device (such as Figure 2 The first indication information described in the corresponding embodiment, or, Figure 2The second indication information described in the corresponding embodiment) is recorded, or when the UE needs to report time period 3 (for example, in scenario four, when the UE re-establishes successfully or the RRC is established successfully, for example, when the UE sends an RRC re-establishment completion message to the re-established cell or the UE sends an RRC establishment completion message to the cell in the RRC establishment process), the above-mentioned time period 3 is recorded, and / or the time period composed of time period 2 and time period 3 is recorded, and / or the time period composed of time period 1, time period 2, and time period 3 is recorded, for example, it can be recorded in another variable or information element, which can be newly defined or reused, such as timeSinceFailure or others, without limitation.

[0346] For another example, in the event of a traditional handover failure, the UE may record one or more of the following information:

[0347] Time period 4, the time period 4 is the time period from when the UE receives the RRC reconfiguration message to when the UE receives the traditional handover message,

[0348] Time period 5, the time period 6 is the time period from when the UE receives the traditional handover message to when the traditional handover fails,

[0349] Time period 6, the time period 6 is the time period from the failure of traditional switching to the UE determining the second cell, wherein "UE determines the second cell" can be replaced by "UE re-establishes", that is, the time period 7 can be the time period from the failure of traditional switching to the UE re-establishing.

[0350] Time period 7, the time period 7 is the time period from when the UE determines the second cell to when the UE reports the time period 7, wherein "the UE determines the second cell" can be replaced by "the UE reestablishes", that is, the time period 7 can be the time period from when the UE reestablishes to when the UE reports the time period 7. Or,

[0351] The time period 4 to the time period 7 is composed of any two or more consecutive time periods.

[0352] It should be noted that the time when the traditional handover fails and the time when the UE determines the second cell may be equal or different. When the two times are equal, time period 6 is "0" or the UE does not need to record time period 6. At this time, time period 5 can be replaced by "the time period 5 is the time period from when the UE receives the traditional handover message to when the UE determines the second cell", and time period 7 can be replaced by "the time period 7 is the time period from when the traditional handover fails to when the UE reports the time period 7".

[0353] It should be noted that the above time period 4 to time period 7, or the time period obtained according to time period 4 to time period 7, in a specific implementation, can be: when a traditional switching failure occurs, record one or more of the following time periods: time period 4, time period 5, time period 6, and a time period obtained according to any two or more consecutive time periods from time period 4 to time period 6, for example, can be recorded in the same variable or cell, and the variable or cell can be newly defined or reuse an existing one, such as timeConnFailure or others, without limitation. Upon receiving a request for reporting recorded information sent by a network device (such as Figure 2 The first indication information described in the corresponding embodiment, or, Figure 2 The second indication information described in the corresponding embodiment) is recorded, or when the UE needs to report time period 7 (for example, in scenario four, when the UE re-establishes successfully or the RRC is established successfully, for example, when the UE sends an RRC re-establishment completion message to the re-established cell or when the UE sends an RRC establishment completion message to the cell in the RRC establishment process), the above-mentioned time period 7 is recorded, and / or the time period composed of time period 6 and time period 7 is recorded, and / or the time period obtained by combining the new time period composed of time period X to time period 6 with time period 7, where X is any value from 4 to 5, for example, it can be recorded in another variable or information element, which can be newly defined or reused, such as timeSinceFailure or others, without limitation.

[0354] For another example, when the UE fails to access or switch to the first candidate cell that meets the execution condition of CHO, the UE may record one or more of the following information:

[0355] Time period 8, where time period 8 is a time period from when the UE receives the RRC reconfiguration message to when the UE determines that the first candidate cell satisfies the execution condition of the conditional switching.

[0356] Time period 9, where time period 9 is a time period from when the UE determines that the first candidate cell satisfies the execution condition of the conditional switching to when the UE fails to switch or access the first candidate cell,

[0357] Time period 10, the time period 10 is the time period from the UE switching to the first candidate cell or the access failure to the UE determining the second cell, wherein "UE determines the second cell" can be replaced by "UE re-establishes", that is, the time period 12 can be the time period from the UE switching to the first candidate cell or the access failure to the UE re-establishing.

[0358] Time period 11, the time period 11 is the time period from when the UE determines the second cell to when the UE reports the time period 11, wherein "UE determines the second cell" can be replaced by "UE reestablishes", that is, the time period 11 can be the time period from when the UE reestablishes to when the UE reports the time period 11. Or,

[0359] A time period consisting of any two or more consecutive time periods from the time period 8 to the time period 11.

[0360] It should be noted that the moment when the UE switches to or fails to access the first candidate cell may be equal to or different from the moment when the UE determines the second cell. When the two moments are equal, time period 10 is "0" or the UE does not need to record time period 10. At this time, time period 9 can be replaced by "the time period 9 is the time period from when the UE determines the first candidate cell that meets the execution conditions of the conditional switching to when the UE determines the second cell", and time period 11 can be replaced by "the time period 11 is the time period from when the UE switches to or fails to access the first candidate cell to when the UE reports the time period 11".

[0361] It should be noted that the above time period 8 to time period 11, or the time period obtained according to time period 8 to time period 11, in a specific implementation, can be: when the UE fails to access or switch to a candidate cell that meets the execution conditions of CHO (i.e., the first candidate cell), one or more of the following time periods are recorded: time period 8, time period 9, time period 10, and time periods obtained according to any two or more consecutive time periods from time period 8 to time period 10. For example, they can be recorded in the same variable or information element, which can be newly defined or reuse existing ones, such as timeConnFailure or others, without limitation. Upon receiving a request for reporting recorded information sent by a network device (such as Figure 2 The first indication information described in the corresponding embodiment, or, Figure 2 The second indication information described in the corresponding embodiment) is recorded, or when the UE needs to report the time period 11 (for example, in scenario four, when the UE re-establishes successfully or the RRC is established successfully, for example, when the UE sends an RRC re-establishment completion message to the re-established cell or when the UE sends an RRC establishment completion message to the cell in the RRC establishment process), the above-mentioned time period 11 is recorded, and / or the time period composed of the time period 10 and the time period 11 is recorded, and / or the time period obtained by combining the new time period composed of the time period X to the time period 10 with the time period 11, wherein X is any value from 8 to 9, for example, it can be recorded in another variable or information element, which can be newly defined or reuse an existing one, such as timeSinceFailure or others, without limitation.

[0362] In this scenario four, if the re-establishment is successful, the UE includes indication information in the RRC re-establishment completion message sent to the re-established cell (or the network device to which the re-established cell belongs), and the indication information is used to indicate that the UE has recorded one or more of the above information 1)-6). If the re-establishment fails, the UE includes indication information in the RRC establishment completion message sent to the cell in the RRC establishment process (or the network device to which the cell belongs), and the indication information is used to indicate that the UE has recorded one or more of the above information 1) to 6).

[0363] The above scheme provides relevant information that can be recorded by the UE in different scenarios of the CHO mechanism, so as to report the relevant information later, so that the network equipment can adjust the parameters according to the relevant information reported by the UE, thereby improving the reliability and robustness of the system.

[0364] based on Figure 1 The network architecture shown in Figure 2 As shown, the present application provides a communication method, which can be used to enable UE to report relevant information in the CHO process to the network device based on the request of the network device. The method can be executed by the terminal device or a component (such as a chip, circuit, etc.) used for the terminal device on the terminal device side; on the network side, it can be executed by the network device or a component (such as a chip, circuit, etc.) used for the network device. For ease of explanation, the following is an example of a terminal device and a network device executing the method, and the terminal device is described by taking UE as an example.

[0365] The method comprises the following steps:

[0366] Step 201: A first network device sends first indication information to a UE. Correspondingly, the UE may receive the first indication information.

[0367] The first indication information is used to request the UE to report the first information. In one example, the first indication information may be a UEInformation Request message. Optionally, the first indication information may include third information and / or fourth information, for example, the third information is used to indicate the relevant information when the UE reports access / handover failure, and the fourth information is used to indicate the relevant information when the UE reports access / handover success.

[0368] Specifically, in scenario one, the first network device may be a network device to which the first cell belongs.

[0369] In scenario 2, the first network device may be a network device to which the first candidate cell belongs.

[0370] In scenario three, if the re-establishment is successful, the first network device may be a network device to which the re-established cell belongs; if the re-establishment fails, the first network device may be a network device to which the cell in the RRC establishment process belongs.

[0371] In scenario 4, if the re-establishment is successful, the first network device may be a network device to which the re-established cell belongs; if the re-establishment fails, the first network device may be a network device to which the cell in the RRC establishment process belongs.

[0372] Step 202: The UE reports first information to the first network device.

[0373] In the above scenario 1, the first information recorded and reported by the UE is part or all of the information described in the above scenario 1. In the above scenario 2, the first information recorded and reported by the UE is part or all of the information described in the above scenario 2. In the above scenario 3, the first information recorded and reported by the UE is part or all of the information described in the above scenario 3. In the above scenario 4, the first information recorded and reported by the UE is part or all of the information described in the above scenario 4.

[0374] For each of the above scenarios, when the UE reports the first information, it can be reported through one RRC message (for example, the message is at the UE granularity), or it can be reported in multiple RRC messages (for example, the message is at the cell granularity). The RRC message can use a newly defined RRC message, or reuse an existing RRC message (for example, UEInformationResponse), without limitation. Optionally, the UE can also report the fifth information and / or the sixth information, for example, the fifth information is used to indicate that the UE reports the relevant information when the access / handover fails, and the sixth information is used to indicate that the UE reports the relevant information when the access / handover is successful.

[0375] Optionally, in addition to reporting the first information according to the request of the first network device as mentioned above, it can also be reported periodically (the reporting period length can be agreed upon by protocol or indicated by the network, for example, the reporting period length can be included in the RRC message containing CHO configuration information), or reported based on events, for example, the first information is reported when the UE successfully accesses or switches to the first cell, or, the first information is reported when the UE successfully accesses or switches to the first candidate cell, or, the first information is reported when the UE re-establishes, or, the first information is reported when the UE performs RRC establishment.

[0376] Based on the above scheme, the UE can report the relevant information in the recorded CHO process to the first network device, so that the network device can adjust the switching parameters (such as traditional switching configuration information or CHO configuration information) according to the obtained relevant information, thereby improving the system reliability and robustness.

[0377] Optionally, the following step 203 may also be included.

[0378] Step 203: The first network device sends part or all of the first information to the third network device.

[0379] For ease of explanation, the network device to which the source cell belongs is referred to as the source network device, the network device to which the candidate cell belongs is referred to as the candidate network device, the network device to which the re-established cell belongs is referred to as the re-established network device, and the network device to which the target cell (here refers to the target cell in the traditional handover) belongs is referred to as the target network device. The following is an example in which the source network device, the target network device, the candidate network device, and the re-established network device are different from each other. Among them, the third network device may include at least one network device. When the third network device includes multiple network devices, the information sent by the first network device to the multiple network devices may be the same or different, and this embodiment does not limit this.

[0380] Specifically,

[0381] In scenario one, the first network device may be a network device to which the first cell belongs, and the third network device may be a source network device and / or a target network device and / or a candidate network device. For example, in scenario one, in the case of RLF in the source cell, the third network device may be a source network device; in the case of a traditional failure, the third network device may be a target network device and / or a source network device, and in one example, when the third network device is a source network device, the third network device (i.e., the source network device) may also send part or all of the information received from the first network device to the target network device; in the case of access or handover failure between the UE and a candidate cell (i.e., the first candidate cell) that meets the execution conditions of CHO, the third network device may be a source network device and / or a candidate network device (for example, the candidate network device may be a network device to which the first candidate cell belongs), and in one example, when the third network device is a source network device, the third network device (i.e., the source network device) may also send part or all of the information received from the first network device to the candidate network device.

[0382] In scenario 2, the first network device may be a network device to which the first candidate cell belongs, and the third network device may be a source network device and / or a network device to which other candidate cells except the first candidate cell belong. For example, in scenario 2, in one example, when the third network device is a source network device, the third network device (i.e., the source network device) may also send part or all of the information received from the first network device to network devices to which other candidate cells except the first candidate cell belong.

[0383] In scenario three or scenario four, if the re-establishment is successful, the first network device may be a network device to which the re-established cell belongs, and the third network device may be a source network device and / or a target network device and / or a candidate network device (the candidate network device includes a network device to which the first cell belongs and / or a network device to which other candidate cells except the first cell belong). Specifically, in scenario three or scenario four, when RLF occurs in the source cell, the third network device may be a source network device and / or a candidate network device (the candidate network device includes a network device to which the first cell belongs and / or a network device to which other candidate cells except the first cell belong). In one example, when the third network device is a source network device, the third network device (i.e., the source network device) may also send part or all of the information received from the first network device to the candidate network device (the candidate network device includes a network device to which the first cell belongs and / or a network device to which other candidate cells except the first cell belong); in the event of a traditional failure, the third network device may be a target network device and / or a source network device and / or a candidate network device (the candidate network device includes a network device to which the first cell belongs and / or a network device to which other candidate cells except the first cell belong). In one example, when the third network device is a source network device, the third network device (i.e., the source network device) may also send part or all of the information received from the first network device to the target network device, and / or , the third network device (i.e., the source network device) may also send part or all of the information received from the first network device to the candidate network device (the candidate network device includes the network device to which the first cell belongs and / or the network device to which other candidate cells except the first cell belong); in the case where the access or handover between the UE and the candidate cell that meets the execution condition of CHO (i.e., the first candidate cell) fails, the third network device may be the source network device and / or the candidate network device (for example, the candidate network device may be the network device to which the first candidate cell belongs and / or the network device to which the first cell belongs and / or the network device to which other candidate cells except the first cell and the first candidate cell belong). In one example, when the third network device is the source network device, the third network device (i.e., the source network device) may also send part or all of the information received from the first network device to the candidate network device (for example, the candidate network device may be the network device to which the first candidate cell belongs and / or the network device to which the first cell belongs and / or the network device to which other candidate cells except the first cell and the first candidate cell belong).

[0384] In scenario three or scenario four, if the re-establishment fails, the first network device may be a network device to which the cell in the RRC establishment process belongs, and the third network device may be a source network device and / or a target network device and / or a candidate network device (the candidate network device includes a network device to which the first cell belongs and / or a network device to which other candidate cells except the first cell belong) and / or a re-establishing network device.For example, in scenario three or scenario four, when RLF occurs in the source cell, the third network device may be a source network device and / or a candidate network device (the candidate network device includes a network device to which the first cell belongs and / or a network device to which other candidate cells belong except the first cell) and / or a re-establishing network device. In one example, when the third network device is a source network device, the third network device (ie, the source network device) may also send part or all of the information received from the first network device to the candidate network device (the candidate network device includes a network device to which the first cell belongs and / or a network device to which other candidate cells belong except the first cell), and / or the third network device (ie, the source network device) The third network device may further send part or all of the information received from the first network device to the re-establishing network device; in the event of a traditional failure, the third network device may be the target network device and / or the source network device and / or the candidate network device (the candidate network device includes the network device to which the first cell belongs and / or the network devices to which other candidate cells except the first cell belong) and / or the re-establishing network device. In one example, when the third network device is the source network device, the third network device (i.e., the source network device) may further send part or all of the information received from the first network device to the target network device, and / or the third network device (i.e., the source network device) may further send part or all of the information received from the first network device to the target network device, and / or the third network device (i.e., the source network device) may further send part or all of the information received from the first network device to the re-establishing network device. The network device sends part or all of the information received to the candidate network device (the candidate network device includes the network device to which the first cell belongs and / or the network devices to which other candidate cells except the first cell belong), and / or the third network device (i.e., the source network device) may also send part or all of the information received from the first network device to the re-establishing network device; in the case where the access or handover between the UE and the candidate cell that meets the execution condition of CHO (i.e., the first candidate cell) fails, the third network device may be the source network device and / or the candidate network device (for example, the candidate network device may be the network device to which the first candidate cell belongs and / or the network device to which the first cell belongs and / or Or a network device belonging to other candidate cells except the first cell and the first candidate cell) and / or a re-establishing network device. In one example, when the third network device is the source network device, the third network device (i.e., the source network device) may also send part or all of the information received from the first network device to the candidate network device (for example, the candidate network device may be a network device belonging to the first candidate cell and / or a network device belonging to the first cell and / or a network device belonging to other candidate cells except the first cell and the first candidate cell), and / or the third network device (i.e., the source network device) may also send part or all of the information received from the first network device to the re-establishing network device.

[0385] The first network device and / or the third network device may adjust parameters (such as traditional handover parameter configuration information or CHO parameter configuration information) according to the received relevant information, thereby improving system reliability and robustness. For example, the CHO configuration information corresponding to at least one candidate cell may be adjusted, or a certain cell may not be configured as a candidate cell in a subsequent CHO process, or a certain cell may not be configured as a target cell in a subsequent traditional handover process.

[0386] As an implementation method, before the above step 201, the UE may also receive second indication information from a second network device, where the second indication information is used to instruct the UE to record part or all of the first information. The second network device may be a source network device. In one example, the second indication information may include multiple indication information, for example, the second indication information may include indication information for instructing the UE to record relevant information when access / handover fails, and / or indication information for instructing the UE to record relevant information when access / handover succeeds.

[0387] As an implementation method, before the above-mentioned step 201, after the UE completes the recording of part or all of the first information, the UE may also send a third indication information to the first network device, and the third indication information is used to indicate that the UE has completed the recording of part or all of the first information. In one example, the third indication information may include multiple indication information, for example, the third indication information may include indication information for indicating that the UE has completed the recording of relevant information when the access / handover fails, and / or, indication information for indicating that the UE has completed the recording of relevant information when the access / handover succeeds. For example, the third indication information may be included in an RRC establishment completion message, an RRC recovery completion message, an RRC re-establishment completion message, an RRC reconfiguration completion message, or other messages, without limitation. Optionally, the UE may also send the third indication information to the second network device.

[0388] As an implementation method, before the above step 201, it may also include: the first network device receives the above first indication information from other network devices (the other network devices may be one of the source network device, the target network device, the candidate network device, the re-established network device, and the network device to which the cell in the RRC establishment process belongs, and are different from the first network device). For example, the first network device is the network device to which the first candidate cell belongs, and the other network device is the source network device, then the source network device may carry the above first indication information in the handover request message sent to the network device to which the first candidate cell belongs, and then, the network device to which the first candidate cell belongs carries the above first indication information in the handover request confirmation message sent to the source network device, and the source network device carries the above first indication information in the RRC reconfiguration message containing the CHO configuration information sent to the UE, and the first indication information may be a binary value or a Boolean value or a certain information element, which is not limited in this embodiment.

[0389] As an example, in any of the above embodiments of the present application, for the above scenario one or scenario two, the above second indication information may be included in an RRC reconfiguration message (the RRC reconfiguration message may be an RRC message including CHO configuration information, or an RRC message for traditional switching (i.e., a switching message)). The UE may include the recorded relevant information in the corresponding scenario (i.e., part or all of the first information in the above scenario one or scenario two) in an RRC reconfiguration completion message sent to a network device to which the successfully accessed cell belongs (i.e., a first network device, for example, in scenario one, the first network device is the network device to which the first cell belongs; in scenario two, the first network device is the network device to which the first candidate cell belongs). Optionally, the RRC reconfiguration completion message may also include third indication information.

[0390] As an example, in any of the above embodiments of the present application, for the above scenario three or scenario four, the above second indication information may be included in an RRC reconfiguration message (the RRC reconfiguration message may be an RRC message containing CHO configuration information, or an RRC message for traditional switching (i.e., a switching message)). In scenario three or scenario four, if the reestablishment is successful, the first network device may be a network device to which the reestablished cell belongs, and the UE may include the relevant information recorded in the corresponding scenario (i.e., part or all of the first information in the above scenario three or scenario four) in the RRC reestablishment completion message sent to the network device to which the reestablished cell belongs. Optionally, the RRC reestablishment completion message may also include third indication information; if the reestablishment fails, the first network device may be a network device to which the cell in the RRC establishment process belongs, and the UE may include the relevant information recorded in the corresponding scenario (i.e., part or all of the first information in the above scenario three or scenario four) in the RRC establishment completion message sent to the network device to which the cell in the RRC establishment process belongs. Optionally, the RRC establishment completion message may also include third indication information.

[0391] In the above embodiment of the present application, the UE can record and report the relevant information generated in the conditional switching process, which has the following beneficial effects:

[0392] It should be noted that the following character " / " means "and / or". For example, record / report includes the following meanings: record, or, report, or, record and report. This is explained here uniformly and will not be repeated later.

[0393] For scenario 1:

[0394] 1) If the relevant information corresponding to the successful access or switching to the first cell is recorded / reported, the network device (such as a candidate network device, a target network device, or a source network device) can know based on the received information that the signal quality of the first cell is good, and the first cell is a cell that meets the cell selection criteria (or meets the S criteria) and the UE can successfully access or switch.

[0395] 2) If the relevant information corresponding to the source cell is recorded / reported, the first network device may subsequently send part or all of the relevant information reported by the UE to the source network device based on the identification information of the source cell. And the network device (such as a candidate network device, or a target network device, or a source network device) knows that the first cell is a cell that meets the cell selection criteria (or meets the S criteria) and the UE can successfully access or switch. If the failure cause value (such as the cause value is "RLF occurs in the source cell") and / or the indication information of the RLF occurrence in the source cell is recorded / reported, the network device (such as a candidate network device, or a target network device, or a source network device) can know that the RLF occurs in the source cell in the CHO process.

[0396] 3) If the identification information of the target cell is recorded / reported, the first network device may send part or all of the relevant information reported by the UE to the target network device based on the identification information of the target cell. According to the signal quality corresponding to the target cell, the failure reason value (e.g., the reason value is "HOF" or "T304 timeout"), and the indication information of the traditional handover failure (or T304 timeout), the network device (e.g., the candidate network device, or the target network device, or the source network device) may know that the traditional handover process is triggered in the CHO process, but the traditional handover fails.

[0397] 4) If the relevant information corresponding to the failure of UE to access or switch to the first candidate cell is recorded / reported, the first network device knows that the quality of the first candidate cell is poor based on the identification information of the first candidate cell, the index information corresponding to the first candidate cell, the CHO configuration information corresponding to the first candidate cell, and the signal quality corresponding to the first candidate cell when the UE fails to access or switch to the first candidate cell. Subsequently, the first network device or the source network device may send part or all of the relevant information reported by the UE to the candidate network device.

[0398] Based on the failure reason value (e.g., the reason value is "the execution conditions of CHO are met but UE access or switching fails"), the indication information that the first candidate cell meets the execution conditions of CHO but UE access or switching fails, the success reason value (e.g., the reason value is "the first cell meets the cell selection criteria (or meets the S criteria) and access or switching is successful"), and the indication information that the first cell meets the cell selection criteria (or meets the S criteria) and access or switching is successful, the first network device (such as a candidate network device or a source network device) can learn that the UE failed to successfully switch to the first candidate cell in the CHO process.

[0399] In addition, in combination with the identification information of the first cell and the identification information of the candidate cell, since the cell selected by the UE after cell selection belongs to the candidate cell, the first network device may consider that the UE's failure to successfully switch to the first candidate cell is an erroneous switch (or, it can be understood that the candidate cell configured in the CHO process is inappropriate, for example, the CHO configuration information of the candidate cell (such as the execution condition information of CHO) is inappropriate, or a certain cell should not be configured as a candidate cell in the CHO process).

[0400] 5) If the signal quality corresponding to some or all of the at least one candidate cell at each moment is recorded / reported, the network device (such as the candidate network device, or the target network device, or the source network device) can know which cells have good signal quality and which cells have poor signal quality at each moment.

[0401] 6) If the time information is recorded / reported, the network device (such as the candidate network device, or the target network device, or the source network device) can adjust the relevant parameters at an appropriate time according to the time information.

[0402] For the above scenario 2:

[0403] 1) If the relevant information corresponding to successful access or switching to the first candidate cell is recorded / reported, the network device (such as the candidate network device, or the target network device, or the source network device) learns, based on the received information, that the signal quality of the first candidate cell is good and the CHO process is successful.

[0404] 2) For other information, please refer to the description of the beneficial effects of scenario 1.

[0405] For the above scenario 3:

[0406] 1) If the relevant information corresponding to the failure of UE to access or switch to the selected first cell is recorded / reported, the network device (such as a candidate network device, a target network device, or a source network device) can learn that the signal quality of the first cell is not ideal based on the identification information of the first cell, the index information corresponding to the first cell, the CHO configuration information corresponding to the first cell, and the signal quality corresponding to the first cell when the UE fails to access or switch to the first cell.

[0407] According to the failure reason value (e.g., the reason value is "the cell meets the cell selection criteria (or meets the S criteria) but access or switching fails", or reuses the existing reason value, such as "HOF", without limitation), the indication information that the cell meets the cell selection criteria (or meets the S criteria) but access or switching fails, the failure reason value (e.g., the reason value is "the execution conditions of CHO are met but UE access or switching fails"), and the indication information that the first candidate cell meets the execution conditions of CHO but UE access or switching fails, the network device (e.g., the candidate network device, or the target network device, or the source network device) can be aware that the CHO process has failed (or, it can be understood that the UE failed to successfully switch to the first candidate cell or the first cell in the CHO process).

[0408] In addition, combined with the identification information of the first cell and the identification information of the source cell, since the cell selected by the UE after cell selection belongs to a candidate cell, the network device (such as a candidate network device, or a target network device, or a source network device) may consider that the UE's failure to successfully switch to the first candidate cell is an erroneous switch (or, it can be understood that the candidate cell configured in the CHO process is inappropriate, for example, the CHO configuration information of the candidate cell (such as the execution condition information of CHO) is inappropriate, or a cell should not be configured as a candidate cell in the CHO process).

[0409] 2) If the corresponding relevant information is recorded / reported when the re-establishment process is performed, the network device (such as a candidate network device, or a target network device, or a source network device, or a re-establishing network device) may know that the CHO process has failed (or, it may be understood that the UE has failed to successfully switch to the first candidate cell or the first cell in the CHO process) based on the re-establishment cause value and the indication information of the access or switching failure between the UE and the first cell that meets the cell selection criteria (or meets the S criteria), or the network device (such as a candidate network device, or a target network device, or a source network device, or a re-establishing network device) may know that the CHO process has failed (or, it may be understood that the UE has failed to successfully switch to the first candidate cell or the first cell in the CHO process), or the network device may consider scenario three to be an erroneous switching or a premature switching (or, it may be understood that the candidate cell configured in the CHO process is inappropriate, for example, the CHO configuration information of the candidate cell (such as the execution condition information of the CHO) is inappropriate, or a certain cell should not be configured as a candidate cell in the CHO process).

[0410] In combination with the identification information of the source cell and the identification information of the re-established cell, if the cell re-established by the UE is the source cell, the network device may consider scenario three to be a premature switch; if the cell re-established by the UE is a cell other than the source cell, the first network device may consider scenario three to be an erroneous switch (or, it may be understood that the candidate cell configured in the CHO process is inappropriate, for example, the CHO configuration information of the candidate cell (such as the execution condition information of CHO) is inappropriate, or a cell should not be configured as a candidate cell in the CHO process).

[0411] 2) For other information, please refer to the description of the beneficial effects of scenario 1.

[0412] For scenario 4:

[0413] 1) If the corresponding relevant information is recorded / reported when the re-establishment process is performed, the network device (such as a candidate network device, or a target network device, or a source network device, or a re-establishing network device) can know that the CHO process has failed (or, it can be understood that the UE failed to successfully switch to the first candidate cell in the CHO process) based on the re-establishment cause value and the indication information that the cell selected by the UE after cell selection meets the cell selection criteria (or meets the S criteria) but does not belong to at least one candidate cell, or the network device (such as a candidate network device, or a target network device, or a source network device, or a re-establishing network device) can consider scenario four to be an erroneous switch or a premature switch (or, it can be understood that the candidate cell configured in the CHO process is inappropriate, for example, the CHO configuration information of the candidate cell (such as the execution condition information of the CHO) is inappropriate, or a cell should not be configured as a candidate cell in the CHO process).

[0414] In addition, in combination with the identification information of at least one candidate cell and the identification information of the source cell, if the UE selects the source cell after cell selection, the network device (such as a candidate network device, or a target network device, or a source network device, or a re-established network device) may consider that the UE's failure to successfully switch to the first candidate cell is a premature switch; if a cell other than the source cell and the candidate cell is selected after cell selection, the network device (such as a candidate network device, or a target network device, or a source network device, or a re-established network device) may consider that the UE's failure to successfully switch to the first candidate cell is an erroneous switch (or, it can be understood that the candidate cell configured in the CHO process is inappropriate, for example, the CHO configuration information of the candidate cell (such as the execution condition information of the CHO) is inappropriate, or a cell should not be configured as a candidate cell in the CHO process).

[0415] 2) For other information, please refer to the description of the beneficial effects of scenario 1.

[0416] The above mainly introduces the solution provided by the present application from the perspective of the interaction between various network elements. It can be understood that in order to realize the above functions, the above-mentioned network elements include hardware structures and / or software modules corresponding to the execution of various functions. Those skilled in the art should easily realize that, in combination with the units and algorithm steps of each example described in the embodiments disclosed in this document, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in hardware or in a computer software-driven hardware manner depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0417] It can be understood that in the above-mentioned method embodiments, the steps or operations implemented by the terminal device can also be implemented by components that can be configured in the terminal device (such as chips or circuits), and the steps or operations implemented by the network device can also be implemented by components that can be configured in the network device (such as chips or circuits).

[0418] The embodiments of the present application also provide a device for implementing any of the above methods, for example, a device is provided including a unit (or means) for implementing each step performed by the terminal device in any of the above methods. For another example, another device is provided, including a unit (or means) for implementing each step performed by the network device in any of the above methods.

[0419] For example, refer to Figure 3 , is a schematic diagram of a communication device provided in an embodiment of the present application. The device is used to implement each step performed by the corresponding terminal device in the above method embodiment, such as Figure 3As shown, the apparatus 300 includes a sending unit 310 and a receiving unit 320. The apparatus may be a terminal device, or a component (such as a chip or a circuit) that may be configured in the terminal device. The apparatus may include one or more of the following possible implementations.

[0420] In the first possible implementation:

[0421] A receiving unit 320 is used to receive first indication information from a first network device, wherein the first indication information is used to request a terminal device to report first information; a sending unit 310 is used to report the first information to the first network device; wherein, when a radio link failure or a traditional switching failure occurs in a source cell of the terminal device, or the terminal device fails to access a first candidate cell that meets the execution conditions of the conditional switching, and the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information includes one or more of the following: identification information of the first cell, index information corresponding to the first cell, signal quality corresponding to the first cell when the terminal device successfully accesses the first cell, a success reason value, or indication information that the first cell meets the cell selection criteria and access is successful; wherein the first cell belongs to the first network device, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is the network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0422] In a possible implementation method, when a radio link failure or a traditional handover failure occurs in a source cell of the terminal device, or the terminal device fails to access a first candidate cell that meets an execution condition of the conditional handover, and the first cell selected by the terminal device after performing cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0423] When the terminal device determines the first cell, the signal quality corresponding to some or all of the at least one candidate cell, or,

[0424] When the terminal device successfully accesses the first cell, the signal quality corresponding to some or all of the at least one candidate cell except the first cell.

[0425] In a possible implementation method, when the terminal device fails to access the first candidate cell that meets the execution condition of the conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0426] When the execution condition of the conditional switching corresponding to the first candidate cell is met, the signal quality corresponding to some or all of the at least one candidate cell, or

[0427] When the terminal device fails to access the first candidate cell, the signal quality corresponding to some or all of the at least one candidate cell.

[0428] In a possible implementation method, when a radio link failure occurs in a source cell of the terminal device, a first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0429] Time period 1, where time period 1 is the time period from when the terminal device receives the RRC reconfiguration message to when the radio link failure occurs in the source cell,

[0430] Time period 2, where time period 2 is a time period from when a radio link failure occurs in the source cell to when the terminal device determines the first cell,

[0431] time period 3, where the time period 3 is a time period from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell,

[0432] time period 4, where the time period 4 is a time period from when the terminal device successfully accesses the first cell to when the terminal device reports the time period 4, or,

[0433] A time period consisting of any two or more consecutive time periods from the time period 1 to the time period 4.

[0434] In a possible implementation method, when conventional handover fails, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0435] Time period 5, the time period 5 is the time period from when the terminal device receives the RRC reconfiguration message to when the terminal device receives the traditional switching message,

[0436] Time period 6, the time period 6 is the time period from when the terminal device receives the traditional switching message to when the traditional switching fails,

[0437] Time period 7, the time period 7 is a time period from the failure of conventional handover to the determination of the first cell by the terminal device,

[0438] time period 8, where the time period 8 is a time period from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell,

[0439] time period 9, where the time period 9 is the time period from when the terminal device successfully accesses the first cell to when the terminal device reports the time period 9, or,

[0440] A time period consisting of any two or more consecutive time periods from the time period 5 to the time period 9.

[0441] In a possible implementation method, when the terminal device fails to access the first candidate cell that meets the execution condition of the conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0442] Time period 10, the time period 10 is a time period from when the terminal device receives the RRC reconfiguration message to when the terminal device determines the first candidate cell that meets the execution condition of the conditional switching,

[0443] time period 11, the time period 11 is a time period from when the terminal device determines that the first candidate cell satisfies the execution condition of the conditional switching to when the terminal device fails to access the first candidate cell,

[0444] time period 12, the time period 12 being a time period from when the terminal device fails to access the first candidate cell to when the terminal device determines the first cell,

[0445] time period 13, where the time period 13 is a time period from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell.

[0446] time period 14, the time period 14 being the time period from when the terminal device successfully accesses the first cell to when the terminal device reports the time period 14, or,

[0447] A time period consisting of any two or more consecutive time periods from the time period 10 to the time period 14.

[0448] In a possible implementation method, the receiving unit 320 is further configured to receive indication information for instructing to record the first information before receiving the first indication information.

[0449] In a possible implementation method, the sending unit 310 is further configured to send indication information for indicating that recording of the first information has been completed to the first network device before the receiving unit 320 receives the first indication information.

[0450] In the second possible implementation:

[0451] The receiving unit 320 is configured to receive first indication information from a first network device, wherein the first indication information is used to request the terminal device to report first information; and the sending unit 310 is configured to report the first information to the first network device. Wherein, when a radio link failure or a traditional handover failure occurs in a source cell of the terminal device, or when the terminal device fails to access a first candidate cell that meets the execution conditions of the conditional handover, and the first cell selected by the terminal device after performing cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information includes one or more of the following:

[0452] The identification information of the first cell, the index information corresponding to the first cell, the conditional switching configuration information corresponding to the first cell, the signal quality corresponding to the first cell when the terminal device fails to access the first cell, the failure reason value, or the indication information that the first cell meets the cell selection criteria and the access fails;

[0453] The first network device is a network device to which the re-established cell belongs, or a network device to which the cell in the RRC establishment process belongs, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0454] In a possible implementation method, when a radio link failure occurs in a source cell of the terminal device, or a traditional handover fails, or the terminal device fails to access a first candidate cell that meets an execution condition of the conditional handover, and the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0455] When the terminal device determines the first cell, the signal quality corresponding to some or all of the at least one candidate cell,

[0456] when the terminal device fails to access the first cell, signal quality corresponding to some or all of the at least one candidate cell except the first cell, or,

[0457] When the terminal device executes the re-establishment process, the signal quality corresponding to some or all of the at least one candidate cell except the first cell.

[0458] In a possible implementation method, when the terminal device fails to access a first candidate cell that meets an execution condition of conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0459] When the execution condition of the conditional switching corresponding to the first candidate cell is met, the signal quality corresponding to some or all of the at least one candidate cell, or

[0460] When the terminal device fails to access the first candidate cell, the signal quality corresponding to some or all of the at least one candidate cell.

[0461] In a possible implementation method, when a radio link failure occurs in a source cell of the terminal device, a first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0462] Time period 1, where time period 1 is the time period from when the terminal device receives the RRC reconfiguration message to when the radio link failure occurs in the source cell,

[0463] Time period 2, where time period 2 is a time period from when a radio link failure occurs in the source cell to when the terminal device determines the first cell,

[0464] time period 3, where the time period 3 is a time period from when the terminal device determines the first cell to when the terminal device fails to access the first cell,

[0465] Time period 4, the time period 4 is a time period from when the terminal device fails to access the first cell to when the terminal device determines to re-establish the cell,

[0466] time period 5, the time period 5 being the time period from when the terminal device determines to re-establish the cell to when the terminal device reports the time period 5, or,

[0467] A time period consisting of any two or more consecutive time periods from the time period 1 to the time period 5.

[0468] In a possible implementation method, when conventional handover fails, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0469] Time period 6, the time period 6 is the time period from when the terminal device receives the RRC reconfiguration message to when the terminal device receives the traditional switching message,

[0470] Time period 7, the time period 7 is the time period from when the terminal device receives the traditional switching message to when the traditional switching fails,

[0471] Time period 8, the time period 8 is a time period from the failure of the traditional handover to the determination of the first cell by the terminal device,

[0472] time period 9, where the time period 9 is a time period from when the terminal device determines the first cell to when the terminal device fails to access the first cell,

[0473] Time period 10, the time period 10 is a time period from when the terminal device fails to access the first cell to when the terminal device determines to re-establish the cell,

[0474] Time period 11, the time period 11 is a time period from when the terminal device determines to re-establish a cell to when the terminal device reports the time period 11. Or,

[0475] A time period consisting of any two or more consecutive time periods from the time period 6 to the time period 11.

[0476] In a possible implementation method, when the terminal device fails to access a first candidate cell that meets an execution condition of conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0477] time period 12, the time period 12 being the time period from when the terminal device receives the RRC reconfiguration message to when the terminal device determines the first candidate cell that satisfies the execution condition of the conditional switching,

[0478] time period 13, the time period 13 is a time period from when the terminal device determines that the first candidate cell satisfies the execution condition of the conditional switching to when the terminal device fails to access the first candidate cell,

[0479] time period 14, the time period 14 being a time period from when the terminal device fails to access the first candidate cell to when the terminal device determines the first cell,

[0480] time period 15, the time period 15 being a time period from when the terminal device determines the first cell to when the terminal device fails to access the first cell,

[0481] time period 16, the time period 16 is a time period from when the terminal device fails to access the first cell to when the terminal device determines to re-establish the cell,

[0482] time period 17, the time period 17 is a time period from when the terminal device determines to re-establish a cell to when the terminal device reports the time period 17, or,

[0483] A time period consisting of any two or more consecutive time periods from the time period 12 to the time period 17.

[0484] In a possible implementation method, before receiving the first indication information from the first network device, the method further includes:

[0485] Instruction information for instructing to record the first information is received.

[0486] In a possible implementation method, the sending unit 310 is further configured to send indication information for indicating that recording of the first information has been completed to the first network device before the receiving unit 320 receives the first indication information.

[0487] It can be understood that the above-mentioned units can also be called modules or circuits, etc., and the above-mentioned units can be independently provided or fully or partially integrated.

[0488] In some possible implementations, the sending unit 310 and the receiving unit 320 may also be implemented by a transceiver unit, or the sending unit 310 and the receiving unit 320 may also be collectively referred to as a transceiver unit. The sending unit 310 and the receiving unit 320 or the transceiver unit may also be referred to as a communication interface.

[0489] Optionally, the communication device 300 may further include a storage unit for storing data or instructions (also referred to as codes or programs), and the above-mentioned units may interact or couple with the storage unit to implement corresponding methods or functions.

[0490] For example, refer to Figure 4 , is a schematic diagram of a communication device provided in an embodiment of the present application. The device is used to implement each step performed by the corresponding network device in the above method embodiment, such as Figure 4As shown, the device 400 includes a sending unit 410 and a receiving unit 420. The device may be a network device, or a component (such as a chip or circuit) that may be configured in a network device. The device may include one or more of the following possible implementations. In the first possible implementation:

[0491] A sending unit 410 is used to send first indication information to a terminal device, wherein the first indication information is used to request the terminal device to report first information; a receiving unit 420 is used to receive the first information from the terminal device; wherein, when a radio link failure or a traditional switching failure occurs in a source cell of the terminal device, or the terminal device fails to access a first candidate cell that meets the execution conditions of the conditional switching, and the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information includes one or more of the following: identification information of the first cell, index information corresponding to the first cell, signal quality corresponding to the first cell when the terminal device successfully accesses the first cell, a success reason value, or indication information that the first cell meets the cell selection criteria and access is successful; wherein the first cell belongs to the first network device, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is the network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0492] In a possible implementation method, when a radio link failure or a traditional handover failure occurs in a source cell of the terminal device, or the terminal device fails to access a first candidate cell that meets an execution condition of the conditional handover, and the first cell selected by the terminal device after performing cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0493] When the terminal device determines the first cell, the signal quality corresponding to some or all of the at least one candidate cell, or,

[0494] When the terminal device successfully accesses the first cell, the signal quality corresponding to some or all of the at least one candidate cell except the first cell.

[0495] In a possible implementation method, when the terminal device fails to access the first candidate cell that meets the execution condition of the conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0496] When the execution condition of the conditional switching corresponding to the first candidate cell is met, the signal quality corresponding to some or all of the at least one candidate cell, or

[0497] When the terminal device fails to access the first candidate cell, the signal quality corresponding to some or all of the at least one candidate cell.

[0498] In a possible implementation method, when a radio link failure occurs in a source cell of the terminal device, a first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0499] Time period 1, where time period 1 is the time period from when the terminal device receives the RRC reconfiguration message to when the radio link failure occurs in the source cell,

[0500] Time period 2, where time period 2 is a time period from when a radio link failure occurs in the source cell to when the terminal device determines the first cell,

[0501] time period 3, where the time period 3 is a time period from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell,

[0502] time period 4, where the time period 4 is a time period from when the terminal device successfully accesses the first cell to when the terminal device reports the time period 4, or,

[0503] A time period consisting of any two or more consecutive time periods from the time period 1 to the time period 4.

[0504] In a possible implementation method, when conventional handover fails, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0505] Time period 5, the time period 5 is the time period from when the terminal device receives the RRC reconfiguration message to when the terminal device receives the traditional switching message,

[0506] Time period 6, the time period 6 is the time period from when the terminal device receives the traditional switching message to when the traditional switching fails,

[0507] Time period 7, the time period 7 is a time period from the failure of conventional handover to the determination of the first cell by the terminal device,

[0508] time period 8, where the time period 8 is a time period from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell,

[0509] time period 9, where the time period 9 is the time period from when the terminal device successfully accesses the first cell to when the terminal device reports the time period 9, or,

[0510] A time period consisting of any two or more consecutive time periods from the time period 5 to the time period 9.

[0511] In a possible implementation method, when the terminal device fails to access the first candidate cell that meets the execution condition of the conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following:

[0512] Time period 10, the time period 10 is a time period from when the terminal device receives the RRC reconfiguration message to when the terminal device determines the first candidate cell that meets the execution condition of the conditional switching,

[0513] time period 11, the time period 11 is a time period from when the terminal device determines that the first candidate cell satisfies the execution condition of the conditional switching to when the terminal device fails to access the first candidate cell,

[0514] time period 12, the time period 12 being a time period from when the terminal device fails to access the first candidate cell to when the terminal device determines the first cell,

[0515] time period 13, where the time period 13 is a time period from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell.

[0516] time period 14, the time period 14 being the time period from when the terminal device successfully accesses the first cell to when the terminal device reports the time period 14, or,

[0517] A time period consisting of any two or more consecutive time periods from the time period 10 to the time period 14.

[0518] In a possible implementation method, the receiving unit 420 is further configured to receive indication information from the terminal device indicating that the recording of the first information has been completed before the sending unit sends the first indication information to the terminal device.

[0519] In the second possible implementation:

[0520] A sending unit 410 is used to send first indication information to a terminal device, wherein the first indication information is used to request the terminal device to report first information; a receiving unit 420 is used to receive the first information from the terminal device; wherein, when a radio link failure or a traditional switching failure occurs in a source cell of the terminal device, or the terminal device fails to access a first candidate cell that meets the execution conditions of the conditional switching, and the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information includes one or more of the following: identification information of the first cell, index information corresponding to the first cell, conditional switching configuration information corresponding to the first cell, signal quality corresponding to the first cell when the terminal device fails to access the first cell, a failure reason value, or indication information that the first cell meets the cell selection criteria and access fails; wherein the first network device is a network device to which the re-established cell belongs, or a network device to which a cell during the RRC establishment process belongs, and the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

[0521] In a possible implementation method, when a radio link failure occurs in a source cell of the terminal device, or a traditional handover fails, or the terminal device fails to access a first candidate cell that meets an execution condition of the conditional handover, and the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0522] When the terminal device determines the first cell, the signal quality corresponding to some or all of the at least one candidate cell, or,

[0523] when the terminal device fails to access the first cell, signal quality corresponding to some or all of the at least one candidate cell except the first cell,

[0524] When the terminal device executes the re-establishment process, the signal quality corresponding to some or all of the at least one candidate cell except the first cell.

[0525] In a possible implementation method, when the terminal device fails to access a first candidate cell that meets an execution condition of conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0526] When the execution condition of the conditional switching corresponding to the first candidate cell is met, the signal quality corresponding to some or all of the at least one candidate cell, or

[0527] When the terminal device fails to access the first candidate cell, the signal quality corresponding to some or all of the at least one candidate cell.

[0528] In a possible implementation method, when a radio link failure occurs in a source cell of the terminal device, a first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0529] Time period 1, where time period 1 is the time period from when the terminal device receives the RRC reconfiguration message to when the radio link failure occurs in the source cell,

[0530] Time period 2, where time period 2 is a time period from when a radio link failure occurs in the source cell to when the terminal device determines the first cell,

[0531] time period 3, where the time period 3 is a time period from when the terminal device determines the first cell to when the terminal device fails to access the first cell,

[0532] Time period 4, the time period 4 is a time period from when the terminal device fails to access the first cell to when the terminal device determines to re-establish the cell,

[0533] time period 5, the time period 5 being the time period from when the terminal device determines to re-establish the cell to when the terminal device reports the time period 5, or,

[0534] A time period consisting of any two or more consecutive time periods from the time period 1 to the time period 5.

[0535] In a possible implementation method, when conventional handover fails, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0536] Time period 6, the time period 6 is the time period from when the terminal device receives the RRC reconfiguration message to when the terminal device receives the traditional switching message,

[0537] Time period 7, the time period 7 is the time period from when the terminal device receives the traditional switching message to when the traditional switching fails,

[0538] Time period 8, the time period 8 is a time period from the failure of the traditional handover to the determination of the first cell by the terminal device,

[0539] time period 9, where the time period 9 is a time period from when the terminal device determines the first cell to when the terminal device fails to access the first cell,

[0540] Time period 10, the time period 10 is a time period from when the terminal device fails to access the first cell to when the terminal device determines to re-establish the cell,

[0541] Time period 11, the time period 11 is a time period from when the terminal device determines to re-establish a cell to when the terminal device reports the time period 11. Or,

[0542] A time period consisting of any two or more consecutive time periods from the time period 6 to the time period 11.

[0543] In a possible implementation method, when the terminal device fails to access a first candidate cell that meets an execution condition of conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information further includes one or more of the following:

[0544] time period 12, the time period 12 being the time period from when the terminal device receives the RRC reconfiguration message to when the terminal device determines the first candidate cell that satisfies the execution condition of the conditional switching,

[0545] time period 13, the time period 13 is a time period from when the terminal device determines that the first candidate cell satisfies the execution condition of the conditional switching to when the terminal device fails to access the first candidate cell,

[0546] time period 14, the time period 14 being a time period from when the terminal device fails to access the first candidate cell to when the terminal device determines the first cell,

[0547] time period 15, the time period 15 being a time period from when the terminal device determines the first cell to when the terminal device fails to access the first cell,

[0548] time period 16, the time period 16 is a time period from when the terminal device fails to access the first cell to when the terminal device determines to re-establish the cell,

[0549] time period 17, the time period 17 is a time period from when the terminal device determines to re-establish a cell to when the terminal device reports the time period 17, or,

[0550] A time period consisting of any two or more consecutive time periods from the time period 12 to the time period 17.

[0551] In a possible implementation method, the receiving unit 420 is further configured to receive indication information from the terminal device indicating that the recording of the first information has been completed before the sending unit sends the first indication information to the terminal device.

[0552] It can be understood that the above-mentioned units can also be called modules or circuits, etc., and the above-mentioned units can be independently provided or fully or partially integrated.

[0553] In some possible implementations, the sending unit 410 and the receiving unit 420 may also be implemented by a transceiver unit, or the sending unit 410 and the receiving unit 420 may also be collectively referred to as a transceiver unit. The sending unit 410 and the receiving unit 420 or the transceiver unit may also be referred to as a communication interface.

[0554] Optionally, the communication device 400 may further include a storage unit for storing data or instructions (also referred to as codes or programs), and the above-mentioned units may interact or couple with the storage unit to implement corresponding methods or functions.

[0555] It should be understood that the division of the units in the above device is only a division of logical functions. In actual implementation, they can be fully or partially integrated into one physical entity, or they can be physically separated. And the units in the device can all be implemented in the form of software calling through processing elements; they can also be all implemented in the form of hardware; some units can also be implemented in the form of software calling through processing elements, and some units can be implemented in the form of hardware. For example, each unit can be a separately established processing element, or it can be integrated in a certain chip of the device. In addition, it can also be stored in the memory in the form of a program, and called and executed by a certain processing element of the device. The function of the unit. In addition, all or part of these units can be integrated together, or they can be implemented independently. The processing element described here can also be a processor, which can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each unit above can be implemented by an integrated logic circuit of hardware in the processor element or in the form of software calling through a processing element.

[0556] In one example, the unit in any of the above devices may be one or more integrated circuits configured to implement the above method, such as one or more application specific integrated circuits (ASIC), or one or more digital singnal processors (DSP), or one or more field programmable gate arrays (FPGA), or a combination of at least two of these integrated circuit forms. For another example, when the unit in the device can be implemented in the form of a processing element scheduler, the processing element can be a general-purpose processor, such as a central processing unit (CPU) or other processor that can call a program. For another example, these units can be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0557] The above unit for receiving (e.g., receiving unit) is an interface circuit of the device, which is used to receive signals from other devices. For example, when the device is implemented in the form of a chip, the receiving unit is an interface circuit of the chip used to receive signals from other chips or devices. The above unit for sending (e.g., sending unit) is an interface circuit of the device, which is used to send signals to other devices. For example, when the device is implemented in the form of a chip, the sending unit is an interface circuit of the chip used to send signals to other chips or devices.

[0558] An embodiment of the present application also provides a communication device, a unit (or means) for implementing each step performed by a terminal device in any of the above methods or a unit (or means) for implementing each step performed by a network device in any of the above methods. The communication device may include a processor and a memory, the memory is used to store computer-executable instructions, and when the device is running, the processor executes the computer-executable instructions stored in the memory so that the device executes the methods described in the above aspects. The device may be a network device or a chip for a network device, or a terminal device or a chip for a terminal device.

[0559] refer to Figure 5 , which is a schematic diagram of the structure of a terminal device provided in an embodiment of the present application. The terminal device is used to implement the operations of the terminal device in the above embodiment. Figure 5As shown, the terminal device includes: an antenna 510, a radio frequency device 520, and a signal processing part 530. The antenna 510 is connected to the radio frequency device 520. In the downlink direction, the radio frequency device 520 receives information sent by the network device through the antenna 510, and sends the information sent by the network device to the signal processing part 530 for processing. In the uplink direction, the signal processing part 530 processes the information of the terminal device and sends it to the radio frequency device 520. The radio frequency device 520 processes the information of the terminal device and sends it to the network device through the antenna 510.

[0560] The signal processing part 530 is used to process each communication protocol layer of the data. The signal processing part 530 can be a subsystem of the terminal device, and the terminal device can also include other subsystems, such as a central processing subsystem, which is used to process the terminal device operating system and application layer; for example, the peripheral subsystem is used to connect with other devices. The signal processing part 530 can be a separately set chip. Optionally, the above devices can be located in the signal processing part 530.

[0561] The signal processing part 530 may include one or more processing elements 5031, for example, including a main control CPU and other integrated circuits, and an interface circuit 5033. In addition, the signal processing part 530 may also include a storage element 5032. The storage element 5032 is used to store data and programs. The program for executing the method executed by the terminal device in the above method may be stored or may not be stored in the storage element 5032, for example, stored in a memory outside the signal processing part 530, and the signal processing part 530 loads the program into the cache for use when in use. The interface circuit 5033 is used to communicate with the device. The above device may be located in the signal processing part 530, and the signal processing part 530 may be implemented by a chip, which includes at least one processing element and an interface circuit, wherein the processing element is used to execute each step of any method executed by the above terminal device, and the interface circuit is used to communicate with other devices. In one implementation, the unit that implements each step in the above method can be implemented in the form of a processing element scheduling program, for example, the device includes a processing element and a storage element, and the processing element calls the program stored in the storage element to execute the method executed by the terminal device in the above method embodiment. The storage element may be a storage element on the same chip as the processing element, that is, an on-chip storage element.

[0562] In another implementation, the program for executing the method executed by the terminal device in the above method can be in a storage element on a different chip from the processing element, that is, an off-chip storage element. In this case, the processing element calls or loads the program from the off-chip storage element to the on-chip storage element to call and execute the method executed by the terminal device in the above method embodiment.

[0563] In another implementation, the unit of the terminal device implementing each step in the above method may be configured as one or more processing elements, which are arranged on the signal processing part 530. The processing element here may be an integrated circuit, for example: one or more ASICs, or one or more DSPs, or one or more FPGAs, or a combination of these integrated circuits. These integrated circuits may be integrated together to form a chip.

[0564] The units implementing the various steps in the above method can be integrated together and implemented in the form of a system-on-a-chip (SOC), and the SOC chip is used to implement the above method. The chip can integrate at least one processing element and a storage element, and the method executed by the above terminal device can be implemented in the form of a program stored in the storage element by the processing element; or, the chip can integrate at least one integrated circuit to implement the method executed by the above terminal device; or, the above implementation methods can be combined, and the functions of some units can be implemented in the form of a processing element calling a program, and the functions of some units can be implemented in the form of an integrated circuit.

[0565] It can be seen that the above device may include at least one processing element and an interface circuit, wherein at least one processing element is used to execute any method performed by a terminal device provided in the above method embodiments. The processing element may execute part or all of the steps performed by the terminal device in a first manner: that is, by calling a program stored in a storage element; or in a second manner: that is, by combining an integrated logic circuit of hardware in a processor element with instructions to execute part or all of the steps performed by the terminal device; of course, the first manner and the second manner may also be combined to execute part or all of the steps performed by the terminal device.

[0566] The processing element here is the same as described above, and can be a general-purpose processor, such as a CPU, or one or more integrated circuits configured to implement the above method, such as one or more ASICs, or one or more microprocessors DSPs, or one or more FPGAs, etc., or a combination of at least two of these integrated circuit forms. The storage element can be a memory, or a general term for multiple storage elements.

[0567] refer to Figure 6 , is a schematic diagram of the structure of a network device provided in an embodiment of the present application. The network device is used to implement the operation of the network device in the above embodiment. Figure 6As shown, the network device includes: an antenna 610, a radio frequency device 620, and a baseband device 630. The antenna 610 is connected to the radio frequency device 620. In the uplink direction, the radio frequency device 620 receives information sent by the terminal device through the antenna 610, and sends the information sent by the terminal device to the baseband device 630 for processing. In the downlink direction, the baseband device 630 processes the information of the terminal device and sends it to the radio frequency device 620, and the radio frequency device 620 processes the information of the terminal device and sends it to the terminal device through the antenna 610.

[0568] The baseband device 630 may include one or more processing elements 631, for example, including a main control CPU and other integrated circuits, and also includes an interface 633. In addition, the baseband device 630 may also include a storage element 632, which is used to store programs and data; the interface 633 is used to interact with the radio frequency device 620. The interface is, for example, a common public radio interface (CPRI). The above device for the network device may be located in the baseband device 630. For example, the above device for the network device may be a chip on the baseband device 630, and the chip includes at least one processing element and an interface circuit, wherein the processing element is used to execute each step of any method executed by the above network device, and the interface circuit is used to communicate with other devices. In one implementation, the unit for the network device to implement each step in the above method can be implemented in the form of a processing element scheduler. For example, the device for the network device includes a processing element and a storage element, and the processing element calls the program stored in the storage element to execute the method executed by the network device in the above method embodiment. The storage element may be a storage element on the same chip as the processing element, ie, an on-chip storage element, or may be a storage element on a different chip from the processing element, ie, an off-chip storage element.

[0569] In another implementation, the unit of the network device implementing each step in the above method may be configured as one or more processing elements, which are arranged on the baseband device. The processing elements here may be integrated circuits, such as one or more ASICs, or one or more DSPs, or one or more FPGAs, or a combination of these integrated circuits. These integrated circuits may be integrated together to form a chip.

[0570] The units of the network device implementing the various steps in the above method can be integrated together and implemented in the form of a system-on-a-chip (SOC). For example, the baseband device includes the SOC chip to implement the above method. The chip can integrate at least one processing element and a storage element, and the processing element calls the stored program of the storage element to implement the method executed by the above network device; or, the chip can integrate at least one integrated circuit to implement the method executed by the above network device; or, the above implementation methods can be combined, and the functions of some units are implemented by the processing element calling the program, and the functions of some units are implemented by the integrated circuit.

[0571] It can be seen that the above apparatus for network equipment may include at least one processing element and an interface circuit, wherein at least one processing element is used to execute any one of the methods performed by the network equipment provided in the above method embodiments. The processing element may execute part or all of the steps performed by the network equipment in a first manner: that is, by calling a program stored in a storage element; or in a second manner: that is, by combining an integrated logic circuit of hardware in a processor element with instructions to execute part or all of the steps performed by the network equipment; of course, the first manner and the second manner may be combined to execute part or all of the steps performed by the above network equipment.

[0572] The processing element here is the same as described above, and can be a general-purpose processor, such as a CPU, or one or more integrated circuits configured to implement the above method, such as one or more ASICs, or one or more microprocessors DSPs, or one or more FPGAs, etc., or a combination of at least two of these integrated circuit forms. The storage element can be a memory, or a general term for multiple storage elements.

[0573] An embodiment of the present application also provides a communication system, including: Figure 3 The communication device shown and Figure 4 The communication device shown.

[0574] Another embodiment of the present application provides a communication system, including: Figure 5 The terminal equipment shown and Figure 6 The network devices shown.

[0575] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium, (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid state disk (SSD)), etc.

[0576] The various illustrative logic units and circuits described in the embodiments of the present application can be implemented or operated by a general-purpose processor, a digital signal processor, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic, a discrete hardware component, or the design of any combination of the above functions. The general-purpose processor can be a microprocessor, and optionally, the general-purpose processor can also be any traditional processor, controller, microcontroller or state machine. The processor can also be implemented by a combination of computing devices, such as a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a digital signal processor core, or any other similar configuration to implement.

[0577] In one or more exemplary designs, the above functions described in this application can be implemented in hardware, software, firmware, or any combination of the three. If implemented in software, these functions can be stored on a computer-readable medium, or transmitted in the form of one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media and communication media that facilitate the transfer of computer programs from one place to another. The storage medium can be any available medium that can be accessed by any general or special computer. For example, such computer-readable media can include but are not limited to RAM, ROM, EEPROM, CD-ROM or other optical disk storage, disk storage or other magnetic storage devices, or any other medium that can be used to carry or store program codes in the form of instructions or data structures and other forms that can be read by general or special computers, or general or special processors. In addition, any connection can be appropriately defined as a computer-readable medium, for example, if the software is transmitted from a website site, server or other remote resource through a coaxial cable, fiber optic computer, twisted pair, digital subscriber line (DSL) or wirelessly, such as infrared, wireless and microwave, it is also included in the defined computer-readable medium. The disk and disc include compact disk, laser disk, optical disk, digital versatile disc (DVD), floppy disk and blue-ray disc. Disks usually copy data magnetically, while discs usually copy data optically with lasers. The above combinations can also be included in computer readable media.

[0578] Those skilled in the art should be aware that in one or more of the above examples, the functions described in this application can be implemented using hardware, software, firmware, or any combination thereof. When implemented using software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein communication media include any media that facilitates the transmission of a computer program from one place to another. Storage media can be any available media that a general or special-purpose computer can access.

[0579] Although the present application has been described in conjunction with specific features and embodiments thereof, it is obvious that various modifications and combinations may be made thereto without departing from the spirit and scope of the present application. Accordingly, this specification and the drawings are merely exemplary illustrations of the present application as defined by the appended claims, and are deemed to have covered any and all modifications, variations, combinations or equivalents within the scope of the present application. Obviously, a person skilled in the art may make various modifications and variations to the present application without departing from the scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A communication method, characterized in that: include: receiving first indication information from a first network device, where the first indication information is used to request a terminal device to report first information; Reporting the first information to the first network device; Wherein, when a radio link failure or a traditional handover failure occurs in a source cell of the terminal device, or the terminal device fails to access a first candidate cell that meets the execution condition of the conditional handover, and the first cell selected by the terminal device after performing cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information includes one or more of the following: The identification information of the first cell, the index information corresponding to the first cell, the signal quality corresponding to the first cell when the terminal device successfully accesses the first cell, the success reason value, or the indication information that the first cell meets the cell selection criteria and the access is successful; The first cell belongs to the first network device, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is the network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

2. The method according to claim 1, characterized in that In the case where a radio link failure occurs in the source cell of the terminal device, or a traditional handover fails, or the terminal device fails to access a first candidate cell that meets the execution condition of the conditional handover, and the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following: When the terminal device determines the first cell, the signal quality corresponding to some or all of the at least one candidate cell, or, When the terminal device successfully accesses the first cell, the signal quality corresponding to some or all of the at least one candidate cell except the first cell.

3. The method according to claim 1 or 2, characterized in that In the case where the terminal device fails to access the first candidate cell that meets the execution condition of the conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following: When the execution condition of the conditional switching corresponding to the first candidate cell is met, the signal quality corresponding to some or all of the at least one candidate cell, or When the terminal device fails to access the first candidate cell, the signal quality corresponding to some or all of the at least one candidate cell.

4. The method according to claim 1 or 2, characterized in that: In a case where a radio link failure occurs in a source cell of the terminal device, a first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following: Time period 1, where time period 1 is the time period from when the terminal device receives the RRC reconfiguration message to when the radio link failure occurs in the source cell, Time period 2, where time period 2 is a time period from when a radio link failure occurs in the source cell to when the terminal device determines the first cell, time period 3, where the time period 3 is a time period from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell, time period 4, where the time period 4 is a time period from when the terminal device successfully accesses the first cell to when the terminal device reports the time period 4, A time period consisting of any two or more consecutive time periods from the time period 1 to the time period 4.

5. The method according to claim 1 or 2, characterized in that: In the case where conventional handover fails, the first cell selected by the terminal device after performing cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes at least one of the following: Time period 5, the time period 5 is the time period from when the terminal device receives the RRC reconfiguration message to when the terminal device receives the traditional switching message, Time period 6, the time period 6 is the time period from when the terminal device receives the traditional switching message to when the traditional switching fails, Time period 7, the time period 7 is a time period from the failure of conventional handover to the determination of the first cell by the terminal device, time period 8, where the time period 8 is a time period from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell, time period 9, where the time period 9 is the time period from when the terminal device successfully accesses the first cell to when the terminal device reports the time period 9, or, A time period consisting of any two or more consecutive time periods from the time period 5 to the time period 9.

6. The method according to any one of claims 1 to 3, characterized in that: In the case where the terminal device fails to access the first candidate cell that meets the execution condition of the conditional switching, the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device successfully accesses the first cell, the first information further includes one or more of the following: Time period 10, the time period 10 is a time period from when the terminal device receives the RRC reconfiguration message to when the terminal device determines the first candidate cell that meets the execution condition of the conditional switching, time period 11, the time period 11 is a time period from when the terminal device determines that the first candidate cell satisfies the execution condition of the conditional switching to when the terminal device fails to access the first candidate cell, time period 12, the time period 12 being a time period from when the terminal device fails to access the first candidate cell to when the terminal device determines the first cell, time period 13, where the time period 13 is a time period from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell. time period 14, the time period 14 being the time period from when the terminal device successfully accesses the first cell to when the terminal device reports the time period 14, or, A time period consisting of any two or more consecutive time periods from the time period 10 to the time period 14.

7. The method according to any one of claims 1 to 6, characterized in that: Before receiving the first indication information from the first network device, the method further includes: Instruction information for instructing to record the first information is received.

8. The method according to claim 7, characterized in that Before receiving the first indication information from the first network device, the method further includes: Sending indication information to the first network device to indicate that recording of the first information has been completed.

9. A communication method, characterized in that: include: receiving first indication information from a first network device, where the first indication information is used to request a terminal device to report first information; Reporting the first information to the first network device; Wherein, in the case where a radio link failure occurs in a source cell of the terminal device, or a traditional handover fails, or the terminal device fails to access a first candidate cell that meets the execution condition of the conditional handover, and the first cell selected by the terminal device after cell selection belongs to at least one candidate cell, and the terminal device fails to access the first cell, the first information includes one or more of the following: The identification information of the first cell, the index information corresponding to the first cell, the conditional switching configuration information corresponding to the first cell, the signal quality corresponding to the first cell when the terminal device fails to access the first cell, the failure reason value, or the indication information that the first cell meets the cell selection criteria and the access fails; The first network device is a network device to which the re-established cell belongs, or a network device to which the cell in the RRC establishment process belongs, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

10. A communication method, characterized in that: include: receiving first indication information from a first network device, where the first indication information is used to request a terminal device to report first information; Reporting the first information to the first network device; Wherein, after the terminal device receives the RRC message including the conditional switching configuration information, a first candidate cell that meets the execution condition of the conditional switching is determined, and in the case where the terminal device successfully accesses the first candidate cell, the first information includes one or more of the following: identification information of the first candidate cell, index information corresponding to the first candidate cell, signal quality corresponding to the first candidate cell when the terminal device successfully accesses the first candidate cell, a success reason value, indication information that the first candidate cell meets the execution condition of the conditional switching and the access is successful, or, signal quality corresponding to some or all of the candidate cells other than the first candidate cell among the at least one candidate cell when the terminal device successfully accesses the first candidate cell; The first network device is a network device to which the first candidate cell belongs, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

11. A communication method, characterized in that: include: receiving first indication information from a first network device, where the first indication information is used to request a terminal device to report first information; Reporting the first information to the first network device; Wherein, in the case where a radio link failure occurs in the source cell of the terminal device, or a traditional handover fails, or the terminal device fails to access the first candidate cell that meets the execution condition of the conditional handover, and the cell selected after cell selection does not belong to at least one candidate cell, the first information includes one or more of the following: cell identification information of the re-established cell, signal quality corresponding to the re-established cell when executing the re-establishment process, a re-establishment reason value, indication information that the cell selected by the terminal device after cell selection meets the cell selection criteria but does not belong to at least one candidate cell, or signal quality corresponding to some or all of the at least one candidate cell when the terminal device executes the re-establishment process; The first network device is a network device to which the re-established cell belongs or a network device to which the cell in the RRC establishment process belongs, the at least one candidate cell is indicated by an RRC reconfiguration message from a second network device, the second network device is a network device to which the source cell belongs, and the first candidate cell is one of the at least one candidate cell.

12. A communication device, characterized in that: include: The method comprises a module for executing the method according to any one of claims 1 to 11.

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