A communication method, device and apparatus

Abstract

Embodiments of the present application provide a communication method, device and apparatus, relating to the technical field of wireless communication, to improve the reliability of SN change. In the method, a terminal device can receive first configuration information. If RLF occurs in a source MCG or a source SCG of the terminal device, the terminal device can send a first message. The first message can contain time period information from when the terminal device receives the first configuration information to when the source MCG or the source SCG has a radio link failure, and / or time period information from when the source MCG or the source SCG has the RLF to when the terminal device sends the first message. Based on the scheme, after the terminal device receives the first configuration information, if the source SCG or the source MCG has the RLF, the terminal device can report the time period information, so that the network device can exchange reasonable and effective information among network devices according to the information reported by the terminal device, and then the network device can optimize parameters.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wireless communication, and in particular to a communication method, device and apparatus. BACKGROUND

[0002] To improve the reliability of secondary node (SN) change procedure, conditional primary secondary cell (PSCell) change (CPC) is proposed. In CPC, a network device, such as a network device to which a source primary cell belongs or a network device to which a source PSCell belongs, can provide a user equipment (UE) with CPC configuration information corresponding to one or more candidate target PSCells through a radio resource control (RRC) reconfiguration message. After receiving the RRC reconfiguration message, the UE can determine whether the candidate PSCell meets a PSCell change execution condition, and take the PSCell meeting the PSCell change execution condition as a target PSCell.

[0003] However, the switching of the target PSCell in the above CPC mechanism can fail or succeed, and on the other hand, the network device to which the source primary cell belongs or the network device to which the source PSCell belongs can have a radio link failure. The network needs to minimize and avoid PSCell switching failure and radio link failure in the CPC mechanism to improve the reliability of SN change. SUMMARY

[0004] The present application provides a communication method, device and apparatus for improving the reliability of SN change.

[0005] In a first aspect, an embodiment of the present application provides a communication method. The method can be executed by a terminal device or a chip with similar functions of the terminal device. In the method, the terminal device can receive first configuration information. The first configuration information can include information of at least one candidate target primary secondary cell and corresponding primary secondary cell change execution condition information. For example, the first configuration information can include physical cell identifier (PCI), cell global identifier (CGI), and frequency point of the candidate target primary secondary cell. When radio link failure (RLF) occurs in a source MCG or a source SCG of the terminal device, the terminal device can send a first message. The first message can include first time period information. The first time period information can include at least one of the following: time period information from when the terminal device receives the first configuration information to when the source MCG or the source SCG has RLF; and time period information from when the source MCG or the source SCG has RLF to when the terminal device sends the first message.

[0006] Based on the scheme, after the terminal device receives the first configuration information, if RLF occurs in the source SCG or the source MCG, the terminal device can record the first time period information and report the first time period information, so that the network device can interact with reasonable and effective information among network devices according to the information reported by the terminal device, and then the network device can optimize parameters.

[0007] In a possible implementation, the first message is sent when RLF occurs in the source MCG or the source SCG and the terminal device determines that there is no first cell or cannot determine the first cell according to the first configuration information.

[0008] Based on the scheme, if RLF occurs in the source MCG or the source SCG and there is no first cell in the at least one candidate target primary secondary cell, the terminal device can send the first message, so that the network device can interact with reasonable and effective information among network devices according to the information reported by the terminal device, and then the network device can optimize parameters.

[0009] In a possible implementation, after the RLF of the source SCG, the terminal device can determine the first cell according to the first configuration information, and can also initiate access to the first cell. If the terminal device successfully accesses the first cell, the first time period information can further include at least one of the following: time period information between the start of the RLF of the source SCG and the determination of the first cell by the terminal device; time period information between the determination of the first cell by the terminal device and the successful access of the terminal device to the first cell; and time period information between the successful access of the terminal device to the first cell and the sending of the first message by the terminal device. If the terminal device fails to access the first cell, and the source MCG does not have an RLF, the first time period information can further include at least one of the following: time period information between the start of the RLF of the source SCG and the determination of the first cell by the terminal device; time period information between the determination of the first cell by the terminal device and the failure of the terminal device to access the first cell; and time period information between the failure of the terminal device to access the first cell and the sending of the first message by the terminal device. If the terminal device fails to access the first cell, and the source MCG has an RLF, the first time period information can further include at least one of the following: time period information between the start of the RLF of the source SCG and the determination of the first cell by the terminal device; time period information between the determination of the first cell by the terminal device and the RLF of the source MCG; time period information between the RLF of the source MCG and the failure of the terminal device to access the first cell; and time period information between the failure of the terminal device to access the first cell and the sending of the first message by the terminal device. Alternatively, if the terminal device fails to access the first cell, and the source MCG has an RLF, the first time period information can further include at least one of the following: time period information between the start of the RLF of the source SCG and the determination of the first cell by the terminal device; time period information between the determination of the first cell by the terminal device and the failure of the terminal device to access the first cell; time period information between the failure of the terminal device to access the first cell and the RLF of the source MCG; and time period information between the RLF of the source MCG and the sending of the first message by the terminal device.

[0010] Based on the scheme, after the RLF of the source SCG, the terminal device can determine the first cell according to the first configuration information, and initiate access to the first cell. The terminal device can send different information in different cases such as successful access to the first cell, failure to access the first cell and no RLF of the source MCG, failure to access the first cell and RLF of the source MCG, so that the network device can optimize parameters according to the information reported by the terminal device.

[0011] In a possible implementation, before the RLF of the source MCG or the source SCG, if the terminal device determines the first cell, the first time period information can further include at least one of the following: time period information from when the terminal device receives the first configuration information to when the terminal device determines the first cell; and time period information from when the terminal device determines the first cell to when the RLF of the source MCG or the source SCG occurs.

[0012] Based on the scheme, if the terminal device determines the first cell before the RLF of the source MCG or the source SCG, the terminal device can report time period information from when the terminal device receives the first configuration information to when the terminal device determines the first cell and / or time period information from when the terminal device determines the first cell to when the RLF of the source MCG or the source SCG occurs, so that the network device can optimize parameters according to the information reported by the terminal device.

[0013] In a possible implementation, before the RLF of the source MCG or the source SCG, if the terminal device determines the first cell and successfully accesses the first cell, the first time period information can further include at least one of the following: time period information from when the RLF of the source MCG or the source SCG occurs to when the terminal device accesses the first cell; and time from when the terminal device accesses the first cell to when the terminal device sends the first message.

[0014] Based on the scheme, if the terminal device determines the first cell and successfully accesses the first cell before the RLF of the source MCG or the source SCG, the terminal device can report time period information from when the RLF of the source MCG or the source SCG occurs to when the terminal device accesses the first cell and / or time period information from when the terminal device accesses the first cell to when the terminal device sends the first message, so that the network device can optimize parameters according to the information reported by the terminal device.

[0015] In a possible implementation, if the terminal device determines the first cell before the RLF of the source MCG, and the terminal device fails to access the first cell, and the source SCG does not have an RLF, the first time period information can further include at least one of the following: time period information from the start of the RLF of the source MCG to the failure of the terminal device to access the first cell; time period information from the start of the failure of the terminal device to access the first cell to the sending of the first message by the terminal device. If the terminal device fails to access the first cell, and the source SCG has an RLF, the first time period information can further include at least one of the following: time period information from the start of the RLF of the source MCG to the RLF of the source SCG; time period information from the start of the RLF of the source SCG to the failure of the terminal device to access the first cell; time period information from the start of the failure of the terminal device to access the first cell to the sending of the first message by the terminal device. Alternatively, if the terminal device fails to access the first cell, and the source SCG has an RLF, the first time period information can include at least one of the following: time period information from the start of the RLF of the source MCG to the failure of the terminal device to access the first cell; time period information from the start of the failure of the terminal device to access the first cell to the RLF of the source SCG; time period information from the start of the RLF of the source SCG to the sending of the first message by the terminal device.

[0016] Based on the scheme, if the terminal device determines the first cell before the RLF of the source MCG, the terminal device can report different information in different cases, such as the failure of the terminal device to access the first cell and the source SCG not having an RLF, the failure of the terminal device to access the first cell and the source SCG having an RLF, and the like, so that the network device can optimize parameters according to the reported information.

[0017] In a possible implementation, if the terminal device determines the first cell before the RLF of the source SCG, and the terminal device fails to access the first cell, and the source MCG does not have the RLF, the first time period information can further include at least one of the following: time period information from the start of the RLF of the source SCG to the failure of the terminal device to access the first cell; and time period information from the start of the failure of the terminal device to access the first cell to the sending of the first message by the terminal device. Alternatively, if the terminal device fails to access the first cell, and the source MCG has the RLF, the first time period information can further include at least one of the following: time period information from the start of the RLF of the source SCG to the RLF of the source MCG; time period information from the start of the RLF of the source MCG to the failure of the terminal device to access the first cell; and time period information from the start of the failure of the terminal device to access the first cell to the sending of the first message by the terminal device. Alternatively, if the terminal device fails to access the first cell, and the source MCG has the RLF, the first time period information can further include at least one of the following: time period information from the start of the RLF of the source SCG to the failure of the terminal device to access the first cell; time period information from the start of the failure of the terminal device to access the first cell to the RLF of the source MCG; and time period information from the start of the RLF of the source MCG to the sending of the first message by the terminal device.

[0018] Based on the scheme, if the terminal device determines the first cell before the RLF of the source SCG, the terminal device can report different information in different cases such as the failure of the terminal device to access the first cell and the non-RLF of the source MCG, the failure of the terminal device to access the first cell and the RLF of the source MCG, and the like, so that the network device can perform parameter optimization according to the information reported by the terminal device.

[0019] In a possible implementation, if the terminal device successfully accesses the first cell, and the source MCG or the source SCG has the RLF, the first time period information can further include at least one of the following: time period information from the receiving of the first configuration information by the terminal device to the determination of the first cell by the terminal device; time period information from the determination of the first cell by the terminal device to the successful access of the first cell by the terminal device; and time period information from the successful access of the first cell by the terminal device to the RLF of the source MCG or the source SCG.

[0020] Based on the scheme, the terminal device can report the first message after successfully accessing the first cell, so that the terminal device can interact with reasonable and effective information, and the network device can perform parameter optimization.

[0021] In a possible implementation, the terminal device can further send first indication information. The first indication information indicates that the source MCG has an RLF or the source SCG has an RLF.

[0022] Based on the scheme, the terminal device can indicate the network device that the source SCG has an RLF or the source MCG has an RLF through the first indication information, so that the network device can optimize the parameters.

[0023] In a possible implementation, the first message can further include at least one of the following: cell information of the source primary cell, cell information of the source primary secondary cell, cell information of the at least one candidate target primary secondary cell, indication information that the terminal device receives the first configuration information, indication information that the terminal device determines the first cell or does not determine the first cell, and indication information that the terminal device successfully accesses the first cell or fails to access the first cell.

[0024] Based on the scheme, the terminal device can further report the network device with the cell information of the source primary cell, the cell information of the source primary secondary cell, and the cell information of the at least one candidate target primary secondary cell, so that the network device can know the information of the cells, and further optimize the mobility parameters corresponding to the respective cells.

[0025] In a possible implementation, the terminal device can further send second indication information. The terminal device can further receive a request message in response to the second indication information. The request message requests the terminal device to send the first message. The terminal device can send the first message according to the request message.

[0026] Based on the scheme, the terminal device can record the first message and report the first message when the network device requests the first message.

[0027] In a second aspect, a communication method is provided. The method can be performed by a network device or a chip with similar functions as the network device. In the method, a first network device can receive a first message sent by a terminal device. The first message can include first time period information of the terminal device, and the first time period information includes at least one of the following: time period information from when the terminal device receives the first configuration information to when radio link failure (RLF) occurs in a source master cell group (MCG) or a source secondary cell group (SCG); and time period information from when RLF occurs in the source MCG or the source SCG to when the terminal device sends the first message. The first network device can send a second message to a second network device. The second message can include part or all of the first message. The first network device can be a network device managing a source master cell, and the second network device can be a network device managing a source master secondary cell; or the first network device can be a network device managing a source master cell, and the second network device can be a network device managing at least one candidate target master secondary cell; or the first network device can be a network device managing a source master secondary cell, and the second network device can be a network device managing a source master cell; or the first network device can be a network device managing a source master secondary cell, and the second network device can be a network device managing at least one candidate target master secondary cell; or the first network device can be a network device providing communication for the terminal device, and the second network device can be a network device managing a source master cell; or the first network device can be a network device providing communication for the terminal device, and the second network device can be a network device managing a source master secondary cell; or the first network device can be a network device providing communication for the terminal device, and the second network device can be a network device managing at least one candidate target master secondary cell; and the at least one candidate target master secondary cell can be configured for the terminal device by the network device managing the source master cell of the terminal device.

[0028] Based on the scheme, part or all of the first message can be exchanged between network devices, and then the mobility parameters can be optimized, for example, the CPC-related parameters can be optimized (for example, the parameters corresponding to the candidate target master secondary cell included in the first configuration information can be optimized, specifically, the information of the candidate target master secondary cell can be changed, and / or the master secondary cell change execution condition information can be changed; or the candidate target master secondary cell included in the first configuration information can be deleted, and / or other cells can be added as candidate target master secondary cells), and the reliability of the terminal device changing the SN can be improved.

[0029] In a possible implementation, the second message can further include first information. The first information indicates that the CPC is too late. Here, the too late CPC can be that the network device sends the first configuration information to the terminal device too late.

[0030] Based on the scheme, the network device can determine that the late CPC occurs according to the second message, and then perform mobility parameter optimization, thereby improving the reliability of the terminal device changing the SN.

[0031] In a possible implementation, the first network device can determine that the source SCG or the source MCG has RLF according to the first time period information. The first network device can release the source SCG and / or the source MCG, or change the SCG and / or the MCG, or keep the source SCG and / or the source MCG unchanged. The first network device here can be a network device managing a source primary cell.

[0032] Based on the scheme, the first network device can also determine that the source SCG or the source MCG has RLF according to the information reported by the terminal device, and thus can release the source SCG or the source MCG, or change the SCG or the MCG, or keep the source SCG or the source MCG, thereby improving the system reliability.

[0033] In a possible implementation, the first network device can also receive second indication information sent by the terminal device. The first network device can send a request message to the terminal device in response to the second indication information. The request message here requests the first message. The first network device can receive the first message sent by the terminal device.

[0034] Based on the scheme, the first network device can determine that the terminal device has recorded the first message according to the second indication information, and can request the terminal device to report the first message.

[0035] In a third aspect, the embodiments of the present application also provide a communication method. The method can be executed by a second network device or a chip with similar functions to the second network device. In the method, the second network device can receive a second message sent by a first network device. The second message can contain first time period information of the terminal device. The first time period information can include at least one of the following: time period information from when the terminal device receives the first configuration information to when the source MCG or the source SCG has radio link failure; and time period information from when the source MCG or the source SCG has RLF to when the terminal device sends the first message. The second network device can also send a third message to a third network device. The third message contains part or all of the second message. The first network device is a network device providing communication for the terminal device; the second network device is a network device managing at least one candidate target primary secondary cell; and the third network device is a network device managing the source primary cell or a network device managing the source primary secondary cell.

[0036] Based on the scheme, the network devices can interact with part or all of the second message, and then perform mobility parameter optimization, for example, optimizing CPC related parameters (for example, optimizing the parameters corresponding to the candidate target primary and secondary cells contained in the first configuration information, specifically, changing the information of the candidate target primary and secondary cells, and / or changing the primary and secondary cell change execution condition information; or, deleting the candidate target primary and secondary cells contained in the first configuration information, and / or adding other cells as candidate target primary and secondary cells), to improve the reliability of the terminal device changing the SN.

[0037] In a possible implementation, the third message can include first information, and the first information indicates that the late CPC occurs.

[0038] Based on the scheme, the network device can determine that the late CPC occurs according to the third message, and then perform mobility parameter optimization to improve the reliability of the terminal device changing the SN.

[0039] In a fourth aspect, a communication apparatus is provided, which can include various modules / circuits for performing the methods in the first aspect or any possible implementation of the first aspect, or can further include various modules / circuits for performing the methods in the second aspect or any possible implementation of the second aspect, or can further include various modules / circuits for performing the methods in the third aspect or any possible implementation of the third aspect. The communication apparatus can be a terminal or a chip for a terminal.

[0040] In a fifth aspect, a communication apparatus is provided, which includes a processor and a memory. The memory is configured to store computer-executable instructions, and when the controller runs, the processor executes the computer-executable instructions in the memory to perform the operation steps of the methods in the first aspect or any possible implementation of the first aspect, or perform the operation steps of the methods in the second aspect or any possible implementation of the second aspect, or perform the operation steps of the methods in the third aspect or any possible implementation of the third aspect, using the hardware resources in the controller. The communication apparatus can be a network device or a chip for a network device, and the network device can be a base station.

[0041] In a sixth aspect, the present application provides a computer-readable storage medium, which stores instructions, and when the instructions run on a computer, the computer executes the methods of the above aspects.

[0042] In a seventh aspect, the present application provides a computer program product storing instructions, and when the instructions run on a computer, the computer executes the methods of the above aspects.

[0043] In addition, the beneficial effects of the fourth to seventh aspects can be the beneficial effects shown in the first and second aspects. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 A communication system provided for embodiments of the present application;

[0045] Figure 2 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0046] Figure 3 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0047] Figure 4 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0048] Figure 5 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0049] Figure 6 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0050] Figure 7 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0051] Figure 8 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0052] Figure 9 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0053] Figure 10 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0054] Figure 11 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0055] Figure 12 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0056] Figure 13 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0057] Figure 14 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0058] Figure 15 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0059] Figure 16 One of the exemplary flowcharts of a communication method provided for embodiments of the present application;

[0060] Figure 17 One of the first time period information schematic diagram provided by the embodiment of the application;

[0061] Figure 18 One of the first time period information schematic diagram provided by the embodiment of the application;

[0062] Figure 19 One of the first time period information schematic diagram provided by the embodiment of the application;

[0063] Figure 20 One of the exemplary flow chart of the communication method provided by the embodiment of the application;

[0064] Figure 21 One of the first time period information schematic diagram provided by the embodiment of the application;

[0065] Figure 22 One of the exemplary flow chart of the communication method provided by the embodiment of the application;

[0066] Figure 23 One of the schematic diagram of the terminal device provided by the embodiment of the application;

[0067] Figure 24 One of the schematic diagram of the terminal device provided by the embodiment of the application;

[0068] Figure 25 One of the schematic diagram of the network device provided by the embodiment of the application;

[0069] Figure 26 The block diagram of the communication device provided by the embodiment of the application. DETAILED DESCRIPTION

[0070] In the following, part of the language in the embodiment of the application is explained and described, so as to facilitate the understanding of the person skilled in the art.

[0071] 1) Cell, refers to the area covered by one network device or part of the network device in the mobile communication system. Here, one network device can be referred to as the network device managing the cell.

[0072] 2) Too late conditional primary / secondary cell change (CPC), which means that the network device sends a message for a CPC procedure too late, causing the terminal device to fail to perform a primary / secondary cell switching. For example, a network device to which a source primary cell belongs (referred to as a source primary network device) or a network device to which a source primary / secondary cell belongs (referred to as a source secondary network device) sends first configuration information to the terminal device too late, causing the terminal device to fail to receive the first configuration information, or to determine the first cell, or to successfully access the first cell, before the source MCG (or the source primary network device) or the source SCG (or the source secondary network device) experiences an RLF.

[0073] 3) The terms "system" and "network" in the embodiments of the present application can be used interchangeably. "Multiple" means two or more, and other quantifiers are similar. "And / or" describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can represent the following three cases: A exists alone, A and B exist together, and B exists alone. In addition, for the elements (element) appearing in the singular form "a", "an" and "the", unless the context clearly indicates otherwise, it does not mean "one or only one", but means "one or more than one". For example, "a device" means one or more such devices. Furthermore, "at least one of" means one or any combination of the following associated objects, for example, "at least one of A, B, and C" includes A, B, C, AB, AC, BC, or ABC.

[0074] The technical solutions of the embodiments of the present application can be applied to various communication systems, for example: a long term evolution (LTE) system, a worldwide interoperability for microwave access (WiMAX) communication system, a future 5th generation (5G) system, such as a new radio access technology (NR), and a future communication system, such as a 6G system, etc.

[0075] The present application will present various aspects, embodiments or features around a system that can include multiple devices, components, modules, etc. It should be understood and appreciated that each system can include additional devices, components, modules, etc., and / or can not include all the devices, components, modules, etc. discussed in connection with the drawings. In addition, combinations of these solutions can also be used.

[0076] The network architecture and service scenarios described in the embodiments of the present application are used to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided by the embodiments of the present application. Those skilled in the art can know that, with the evolution of network architecture and the emergence of new service scenarios, the technical solutions provided by the embodiments of the present application are also applicable to similar technical problems.

[0077] The embodiments of the present application can be applied in traditional typical networks, and can also be applied in future UE-centric networks. The UE-centric network introduces a non-cell network architecture, that is, a large number of small stations are deployed in a certain area to form a hyper cell, each small station is a transmission point (TP) or transmission and reception point (TRP) of the hyper cell, and is connected with a centralized controller. When the UE moves in the hyper cell, the network side device selects a new sub-cluster for the UE to serve, thereby avoiding real cell switching and realizing the continuity of UE service. The network side device includes a wireless network device. Alternatively, in the UE-centric network, multiple network side devices, such as small stations, can have independent controllers, such as distributed controllers, and each small station can independently schedule users. The small stations interact with each other in the long term, so that when providing collaborative services for the UE, there is also a certain flexibility.

[0078] In the embodiments of the present application, different base stations can be base stations with different identities, or can be base stations with the same identity deployed in different geographical locations. Since the base station does not know whether it will be involved in the scenario to which the embodiments of the present application are applied before the base station is deployed, the base station, or the baseband chip, should support the method provided by the embodiments of the present application before deployment. It can be understood that the aforementioned base stations with different identities can be base station identities, or can be cell identities or other identities.

[0079] In the embodiments of the present application, some scenarios are described by taking the scenario of the NR network in the wireless communication network as an example. It should be pointed out that the solutions in the embodiments of the present application can also be applied to other wireless communication networks, and the corresponding names can also be replaced by the names of corresponding functions in other wireless communication networks.

[0080] The technical solutions provided by the embodiments of the present application can be applied to wireless communication between communication devices. The wireless communication between the communication devices can include wireless communication between a network device and a terminal device, wireless communication between network devices, and wireless communication between terminal devices. In the embodiments of the present application, the term “wireless communication” can also be referred to as “communication”, and the term “communication” can also be described as “data transmission”, “information transmission” or “transmission”.

[0081] To facilitate understanding of the embodiments of the present application, first take Figure 1 The communication system shown in the figure is taken as an example to describe the communication system applicable to the embodiments of the present application in detail. Figure 1 The communication system shown in the figure is taken as an example to describe the communication system applicable to the embodiments of the present application in detail. Figure 1 As shown in the figure, the communication system 100 includes a first network device 102, a second network device 104 and a third network device 106, and a terminal device 101. The first network device 102, the second network device 104 and the third network device 106 can be configured with multiple antennas, and the terminal device can also be configured with multiple antennas. Optionally, the communication system can also include a terminal device 103 (not shown in the figure).

[0082] In the communication system 100, the first network device 102 can be a network device managing the source MCG of the terminal device 101, the second network device 104 can be a network device managing the source SCG of the terminal device, and the third network device 106 can be a network device managing one of the candidate target primary and secondary cells. Among them, the first network device 102 or the second network device 104 can configure the target primary and secondary cells for the terminal device 101 through first configuration information. The first configuration information can include information of at least one candidate target primary and secondary cell and corresponding primary and secondary cell change execution condition information. The terminal device 101 can determine a first cell satisfying the primary and secondary cell change execution condition according to the first configuration information. The first cell belongs to the third network device 106. The terminal device can then initiate access to the third network device 106.

[0083] The access of the terminal device 101 to the third network device 106 can fail or succeed. When the terminal device fails to access the third network device 106 and the source SCG or the source MCG experiences RLF, the terminal device can report a first message to the first network device 102, the second network device 104 or the third network device 106. The first network device 102, the second network device 104 and the third network device 106 can exchange reasonable and effective information and optimize parameters, thereby improving the reliability of the SN change of the terminal device 101.

[0084] The terminal device to which the present application relates includes a device that provides voice and / or data connectivity for a user, specifically, a device that provides voice for a user, or a device that provides data connectivity for a user, or a device that provides both voice and data connectivity for a user. For example, the terminal device can include a handheld device having wireless connection capability, or a processing device connected to a wireless modem. The terminal device can communicate with a core network via a radio access network (RAN), exchange voice or data with the RAN, or interact with voice and data with the RAN. The terminal device can include a user equipment (UE), a wireless terminal, a mobile terminal, a device-to-device (D2D) terminal, a vehicle to everything (V2X) terminal, a machine-to-machine / Machine-Type Communications (M2M / MTC) terminal, an Internet of Things (IoT) terminal, a subscriber unit, a subscriber station, a mobile station, a remote station, an access point (AP), a remote terminal, an access terminal, a user terminal, a user agent, or a user device, etc. For example, it can include a mobile telephone (or "cellular" telephone), a computer with mobile termination, a portable, pocket, handheld, computer-included mobile device, etc. For example, it can include a personal communication service (PCS) telephone, a cordless telephone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), etc. It can also include a limited device, such as a device with lower power consumption, or a device with limited storage capacity, or a device with limited computing capability, etc. For example, it can include a bar code, a radio frequency identification (RFID) device, a sensor, a global positioning system (GPS), a laser scanner, etc. information sensing device.

[0085] By way of example and not limitation, in embodiments of the present application, the terminal can also be a wearable device. The wearable device can also be referred to as a smart wearable device or a smart wearable device, etc., which is a general term for devices that are designed and developed by applying wearable technology to daily wear, such as glasses, gloves, watches, clothing, and shoes. The wearable device is a portable device that is directly worn on the body or integrated into the user's clothes or accessories. The wearable device is not only a hardware device, but also a powerful function achieved through software support and data interaction, cloud interaction. The broad sense of wearable smart devices includes full-featured, large-size devices that can realize complete or partial functions without relying on smart phones, such as smart watches or smart glasses, and devices that focus on a certain application function and need to be used with other devices such as smart phones, such as various smart wristbands, smart helmets, smart jewelry, etc.

[0086] And the various terminals as introduced above, if located on a vehicle (for example, placed in or installed in the vehicle), can be considered as a vehicle terminal, which is also referred to as an on-board unit (OBU).

[0087] In embodiments of the present application, the device for implementing the function of the terminal can be a terminal, or a device capable of supporting the terminal to implement the function, such as a chip system, which can be installed in the terminal. In embodiments of the present application, the chip system can be composed of a chip, or can include a chip and other discrete devices. In the technical solutions provided in embodiments of the present application, the device for implementing the function of the terminal is taken as an example to describe the technical solutions provided in embodiments of the present application.

[0088] The network device involved in the present application, for example, includes an access network (AN) device, such as a base station (for example, an access point), which can refer to a device in the access network that communicates with a wireless terminal through one or more cells over the air interface, or for example, a network device in a vehicle-to-everything (V2X) technology is a roadside unit (RSU). The base station can be used to convert the received air frames and IP packets into each other as a router between the terminal and the rest of the access network, which can include an IP network. The RSU can be a fixed infrastructure entity supporting V2X applications, and can exchange messages with other entities supporting V2X applications. The network device can also coordinate the management of the properties of the air interface. For example, the network device can include an evolved base station (NodeB or eNB or e-NodeB, evolved Node B) in a long term evolution (LTE) system or long term evolution-advanced (LTE-A), or can also include a next generation node B (gNB) in an evolved packet core network (EPC), a 5th generation (5G), a new radio (NR) system, or can also include a centralized unit (CU) and a distributed unit (DU) in a cloud radio access network (Cloud RAN) system, and the embodiments of the present application are not limited.

[0089] The network device can also include a core network device, for example, including an access and mobility management function (AMF) and the like.

[0090] In the embodiments of the present application, the device for implementing the function of the network device can be a network device, or a device capable of supporting the network device to implement the function, such as a chip system, which can be installed in the network device. In the technical solutions provided in the embodiments of the present application, the device for implementing the function of the network device is taken as an example to describe the technical solutions provided in the embodiments of the present application.

[0091] It should be understood that the technical solutions of the present application can be applied to a multiple radio dual connectivity (MR-DC) communication system. DC refers to supporting two base stations to provide data transmission services for one terminal device at the same time, wherein the base station where the PCell is located is called the primary base station, and the base station where the primary secondary cell (PSCell) is located is called the secondary base station. Among them, MR-DC includes EN-DC, NE-DC, NGEN-DC and other architectures. Here, EN-DC is an architecture in which the LTE base station is used as the primary base station, the NR base station is used as the secondary base station for dual connectivity, and both the primary base station and the secondary base station are connected to the 4G core network (EPC). NE-DC is an architecture in which the NR base station is used as the primary base station, the LTE base station is used as the secondary base station for dual connectivity, and both the primary base station and the secondary base station are connected to the 5G core network. NGEN-DC is an architecture in which the LTE base station is used as the primary base station, and the NR base station is used as the secondary base station for dual connectivity, and the difference from EN-DC is that both the primary base station and the secondary base station are connected to the 5G core network. The network device in the communication system can correspond to the first network device 102, the second network device 104 or the third network device 106 shown in Figure 1 , and the terminal device can correspond to the terminal device 101 shown in Figure 1 . Among them, the terminal device 101 can be connected with the first network device 102 and the second network device 104, the first network device 102 can be the primary base station, and the second network device 104 can be the secondary base station. The plurality of service cells in the first network device 102 form a master cell group (MCG), and the plurality of service cells in the second network device 104 form a secondary cell group (SCG).

[0092] In the following, without loss of generality, the interaction process between one terminal device and a network device is taken as an example to illustrate the embodiments of the present application in detail. The terminal device can be a terminal device in a wireless communication system and has a wireless connection relationship with the network device. It can be understood that the network device can communicate with multiple terminal devices in the wireless communication system based on the same technical solutions. The present application does not limit this.

[0093] Figure 2 is an exemplary flowchart of the communication method provided by the embodiments of the present application from the perspective of device interaction. As Figure 2 indicated, the method can include:

[0094] Step 201: The terminal device receives first configuration information.

[0095] The terminal device can receive the first configuration information from the network device. If the primary secondary cell change is initiated by the primary base station, the terminal device can receive the first configuration information from the source primary base station. If the primary secondary cell change is initiated by the secondary base station, the terminal device can receive the first configuration information from the source secondary base station. The first configuration information contains information of at least one candidate target primary secondary cell and corresponding primary secondary cell change execution condition information. The first configuration information is used to determine the first cell. It should be understood that the first cell is a cell in the at least one candidate target primary secondary cell that satisfies the primary secondary cell change execution condition. The terminal device can also determine whether there is a cell in the at least one candidate target primary secondary cell that satisfies the primary secondary cell change execution condition according to the first configuration information, that is, determine whether the first cell exists. In the following, the information of the at least one candidate target primary secondary cell and the corresponding primary secondary cell change execution condition information are explained and described.

[0096] 1. Information of the candidate target primary secondary cell: can include identification information of each candidate target primary secondary cell. For example, it can be a measurement identifier (measID), or it can be a configuration identifier (such as condReconfigId), or it can be a physical cell identifier (PCI), or it can also be a cell global identifier (CGI). The information of the candidate target primary secondary cell can also include at least one of the following: a cell index of each candidate target primary secondary cell (such as cell index), a cell-radio network temporary identifier (C-RNTI) allocated by each candidate target primary secondary cell to the terminal device, random access channel (RACH) resources required to access the candidate target primary secondary cell, frequency information of each candidate target primary secondary cell, or physical layer configuration parameters, media access control (MAC) layer configuration parameters, radio link control (RLC) layer configuration parameters, packet data convergence protocol (PDCP) layer configuration parameters, service data adaption protocol (SDAP) layer configuration parameters, or radio resource control (RRC) layer configuration parameters of each candidate target primary secondary cell.

[0097] 2. The main secondary cell change execution condition can include a main secondary cell change execution event type and a corresponding threshold value. The main secondary cell change event type can include event A3, event A5 or other execution event types. Each candidate target main secondary cell corresponds to one or more main secondary cell change execution conditions. For example, one candidate target main secondary cell can be configured with one execution event type, and can be configured with at least one threshold value and / or at most two different trigger quantities. The trigger quantity can include reference signal received power (RSRP), reference signal received quality (RSRQ) or signal to interference plus noise ratio (SINR). Wherein the terminal device can determine whether the candidate target main secondary cell meets the main secondary cell change execution condition according to the first configuration information.

[0098] For example, the network device configures the main secondary cell change execution event type of the candidate target main secondary cell A as event A3, and configures the corresponding threshold value as the first threshold value. Then, the terminal device can consider that the candidate target main secondary cell A meets the main secondary cell change condition when the cell signal quality of the candidate target main secondary cell A is higher than that of the source main secondary cell by the first threshold value. In other words, the terminal device can determine that the candidate target main secondary cell A is the first cell. Wherein the cell signal quality can include at least one of RSRP, RSRQ and SINR.

[0099] Step 202: The source main cell group MCG or the source secondary cell group SCG of the terminal device has a radio link failure, and the terminal device sends a first message.

[0100] Wherein, the terminal device can send the first message to the network device. Here, the network device can be a source main base station (source main network device) or a source secondary base station (source secondary network device), or can also be a base station managing the first cell, or can also be a base station currently providing communication services for the terminal device. Optionally, in an embodiment, the terminal device can send second indication information to the network device after recording the first message. The second indication information can inform the network device that the terminal device has recorded the first message, or can be used to trigger the network device to send a request message. The request message is used to request the first message. The network device can send the aforementioned request message to the terminal device after receiving the second indication information. Then, the terminal device can send the first message to the network device according to the request message.

[0101] The first message can include the first time period information. The first time period information can be at least one of the following: time period information T1 between the terminal device receiving the first configuration information and the source MCG or source SCG experiencing RLF, or time period information T2 between the source MCG or source SCG experiencing RLF and the terminal device sending the first message.

[0102] In the scheme, the source MCG experiencing RLF can refer to the source PCell and / or at least one SCell belonging to the source master network device experiencing RLF, and the source SCG experiencing RLF can refer to the source PSCell and / or at least one SCell belonging to the source secondary network device experiencing RLF.

[0103] As shown in FIG. 1, the terminal device receives the first configuration information at t1, the source MCG or source SCG experiences RLF at t2, and the terminal device sends the first message at t3. Therefore, the first message can include T1 or T2 or both T1 and T2. Figure 3 As shown in FIG. 1, the terminal device receives the first configuration information at t1, the source MCG or source SCG experiences RLF at t2, and the terminal device sends the first message at t3. Therefore, the first message can include T1 or T2 or both T1 and T2. Figure 3 As shown in FIG. 1, the terminal device receives the first configuration information at t1, the source MCG or source SCG experiences RLF at t2, and the terminal device sends the first message at t3. Therefore, the first message can include T1 or T2 or both T1 and T2.

[0104] In addition, it should be noted that the specific time of the source MCG or source SCG experiencing RLF can result in different first time period information. In the following, the first time period information is introduced according to the time of the source MCG or source SCG experiencing RLF.

[0105] Example 1: There is no first cell when the source MCG or source SCG experiences RLF.

[0106] In the example, the first time period information can include T1 or T2 or both T1 and T2. Figure 3 As shown in FIG. 1, the terminal device receives the first configuration information at t1, the source MCG or source SCG experiences RLF at t2, and the terminal device sends the first message at t3. Therefore, the first message can include T1 or T2 or both T1 and T2.

[0107] The first network device can send a second message to the second network device when receiving the first message sent by the terminal device. The second message can include part or all of the first message. As shown in FIG. 1, an exemplary flowchart for the terminal device to communicate with the network side can include the following steps: Figure 4 As shown in FIG. 1, an exemplary flowchart for the terminal device to communicate with the network side can include the following steps:

[0108] Step 401: The terminal device sends a first message to the first network device.

[0109] The first message here can include the first message as shown in Figure 3 For example, the first time period information can include T1 or T2 or both T1 and T2.

[0110] The first message can further include indication information of RLF of the source MCG or the source SCG. Optionally, the first message can further include cell information of the source PCell and / or the source PSCell and / or at least one candidate target primary and secondary cell, wherein the cell information includes at least one of the following: PCI, frequency information, CGI, identification information (such as measurement identification, configuration identification). Optionally, the first message can further include signal quality of the cell, such as at least one of the following: signal quality of the source PCell, signal quality of the source PSCell, signal quality of at least one candidate target primary and secondary cell, when the source MCG has RLF. Optionally, the first message can further include indication information that the terminal device receives the first configuration information. Optionally, the first message can further include indication information that the terminal device does not determine the first cell. Optionally, the first message can further include information of at least one candidate target primary and secondary cell and corresponding primary and secondary cell change execution condition information.

[0111] Step 402: The first network device sends a second message to the second network device.

[0112] The second message here can include part or all of the first message described above. For example, the second message can include the first message as shown in Figure 3The first time period information is shown. Among them, if it is CPC initiated by the source SN (i.e., the source secondary network device) managing the source SCG, and the source MCG occurs RLF, then the first network device can be the source SN managing the source SCG, and the second network device can be the source MN (i.e., the source primary network device) managing the source MCG, or also the candidate SN (i.e., the candidate secondary network device) managing the candidate target primary secondary cell. For example, the source SN can send a second message to the source MN and / or the candidate SN, or the source SN can send the second message to the source MN, and the source MN can forward part or all of the second message to the candidate SN. After receiving the second message, the source MN can perform MN reconfiguration. For example, the MN can be replaced (such as configuring other network devices as a new primary network device), or the MCG can be replaced while keeping the MN unchanged (such as configuring other cells under the source MN as a new PCell), or the source MN can be released (such as releasing the source MCG configuration information). After receiving the second message, the candidate SN can perform CPC parameter adjustment, for example, the candidate SN can adjust the first configuration information. The second message can also contain first information. The first information can indicate that the late CPC occurs, i.e., the source SN receives the first message and considers that the late CPC occurs, and the first information can be contained in the second message sent by the source SN. Alternatively, if the source SN sends the first configuration information to the terminal device, the source SN can adjust the time of triggering the CPC preparation process of the source MN and the candidate SN, adjust the primary secondary cell change execution condition information, and adjust the time of sending the first configuration information. When the source MN or the candidate SN receives the first information indicating that the late CPC occurs, alternatively, if the source MN sends the first configuration information to the terminal device, the source MN can adjust the time of performing CPC preparation with the candidate SN and the time of sending the first configuration information according to the first information, and the candidate SN can adjust the information of at least one candidate target primary secondary cell and the time of configuring the information of the candidate target primary secondary cell.

[0113] If the CPC is initiated by the source SN and the RLF occurs in the source SCG, the first network device can be the source MN, and the second network device can be the source SN or can also be a candidate SN. Optionally, after receiving the first message, the source MN can determine that the CPC is late according to the first message, and therefore the source MN can further include first information indicating that the CPC is late in the second message sent to the second network device (such as the source SN). If the first configuration information is sent by the source MN to the terminal device, the source MN can adjust the time of CPC preparation with the candidate SN, the time of sending the first configuration information according to the first message, and the source MN can also release the source SN (such as releasing the source SCG configuration information); or the source MN can also keep the source SN unchanged, for example, the source MN can replace the SCG or the PSCell, and the replaced SCG / PSCell still belongs to the source SN; or the source MN can also change the SN, for example, configuring another network device as a new secondary network device. After receiving the second message sent by the source MN, the source SN can consider that the CPC is late, and can adjust the time of triggering the CPC preparation process of the source MN and the candidate SN, the primary and secondary cell change execution condition information, and the time of sending the first configuration information. After receiving the second message sent by the source MN or forwarded by the source SN, the candidate SN can perform CPC parameter adjustment, for example, the candidate SN can adjust the information of at least one candidate target primary and secondary cell, and the time of configuring the information of the candidate target primary and secondary cell.

[0114] If the CPC is initiated by the source MN and the source MCG experiences RLF, the first network device can be the source SN and the second network device can be the source MN. After receiving the second message, the source MN can determine that the CPC is late according to the second message. For example, the source MN can determine that the CPC is late according to the first time period information in the second message. Here, the late CPC can mean that the network device sends the message (such as the first configuration information) for the CPC procedure too late, causing the terminal device to fail to perform the primary and secondary cell switching. If the first configuration information is sent by the source MN to the terminal device, the source MN can adjust the time for CPC preparation with the candidate SN, the primary and secondary cell change execution condition information, and the time for sending the first configuration information. On the other hand, because the source MCG experiences RLF, the source MN can also adjust the MN, for example, the source MN can replace the MN (such as configuring another network device as a new primary network device), or can replace the MCG while keeping the MN unchanged (such as configuring another cell under the source MN as a new PCell), or can release the source MN (such as releasing the source MCG configuration information). The source MN can also forward the above-mentioned second message to the candidate SN. The second message can include the first information indicating that the CPC is late. After receiving the above-mentioned second message, the candidate SN can adjust the CPC parameters, for example, the candidate SN can adjust the information of at least one candidate target primary and secondary cell, or the candidate SN can also adjust the time for configuring the information of the candidate target primary and secondary cell.

[0115] If the CPC is initiated by the source MN and the source SCG experiences RLF, the first network device can be the source MN and the second network device can be the source SN. After receiving the first message, the source MN can release the source SN, or the source MN can replace the SCG or the PSCell, and the replaced SCG / PSCell still belongs to the source SN; or the source MN can also change the SN, for example, configuring another network device as a new secondary network device. In addition, the source MN can determine that the CPC is late, and if the first configuration information is sent by the source MN to the terminal device, the source MN can adjust the time for CPC preparation with the candidate SN, the primary and secondary cell change execution condition information, and the time for sending the first configuration information. After receiving the second message sent by the source MN, the source SN can adjust the time for triggering the CPC according to the late CPC indication information in the second message. Alternatively, the second network device can also be the candidate SN, and after receiving the above-mentioned second message, the candidate SN can adjust the CPC parameters, for example, the candidate SN can adjust the information of at least one candidate target primary and secondary cell.

[0116] Alternatively, after receiving the second message, the candidate SN can send a third message to the source MN or the source SN, and the third message can include part or all of the second message. Alternatively, the third message can include second information indicating that the CPC is late.

[0117] Example two, the terminal device determines the first cell before the source SCG RLF occurs.

[0118] If the source SCG RLF occurs before the first cell is determined, the terminal device can also continue to determine whether the first cell exists according to the first configuration information. One possibility is that the terminal device determines the first cell after the source SCG RLF occurs, and initiates access to the first cell. It should be noted that according to whether the terminal device successfully accesses the first cell, the first time period information can be divided into the following three cases:

[0119] 1) The terminal device successfully accesses the first cell.

[0120] If the terminal device successfully accesses the first cell, as shown in Figure 5 The first time period information can further include at least one of the following:

[0121] The time period information T1 from when the terminal device receives the first configuration information to when the source SCG RLF occurs; the time period information T3 from when the source SCG RLF occurs to when the terminal device determines the first cell; the time period information T4 from when the terminal device determines the first cell to when the terminal device successfully accesses the first cell; the time period information T5 from when the terminal device successfully accesses the first cell to when the terminal device sends the first message; and the time period information T2 from when the source SCG RLF occurs to when the terminal device sends the first message. For example, the first time period information can be T1, T2, T3 and T4, or the first time period information can be T1, T2, T3, T4 and T5, or the first time period information can be T1, T3, T4 and T5, or the first time period information can be T1 and T2.

[0122] In addition, it should be noted that the first time period information in the embodiments of the present application is only exemplary and is not a limitation of the first time period information. It should be understood that the first time period information can be other variations of the time period information from when the terminal device receives the first configuration information to when the terminal device reports the first message. For example, it can be a combination of each time period from when the terminal device receives the first configuration information to when the terminal device reports the first message, or the entire time period information from when the terminal device receives the first configuration information to when the first message is reported.

[0123] In this scenario, the first message can further include cell information of the source PCell and / or source PSCell and / or the first cell and / or other candidate target primary and secondary cells except the first cell, wherein the cell information includes at least one of the following: PCI, frequency information, CGI, identification information (such as measurement identification, configuration identification). Optionally, the first message can further include signal quality of the cell, such as at least one of the following: signal quality of the source PCell, signal quality of the source PSCell, signal quality of the first cell, and signal quality of the candidate target primary and secondary cells except the first cell, when the source SCG has RLF or when the terminal device successfully accesses the first cell. The first message can further include indication information of the RLF of the source SCG. Optionally, the first message can further include indication information of the reception of the first configuration information by the terminal device. Optionally, the first message can further include indication information of the determination of the first cell by the terminal device. Optionally, the first message can further include indication information of the successful access of the first cell by the terminal device. Optionally, the first message can further include information of at least one candidate target primary and secondary cell and corresponding primary and secondary cell change execution condition information.

[0124] In this scenario, the first network device can be a network device to which the first cell belongs (i.e., a target SN) or a network device that provides communication for the terminal device. The second network device can be a source secondary network device (i.e., a source SN or a network device that manages the source SCG) or a candidate SN.

[0125] 2) The terminal device fails to access the first cell, and the source MCG does not have RLF.

[0126] If the terminal device fails to access the first cell and the source MCG does not have RLF, as shown in FIG. 2, the first time period information can further include at least one of the following: Figure 6

[0127] The time period information T1 between the reception of the first configuration information by the terminal device and the RLF of the source SCG; the time period information T3 between the RLF of the source SCG and the determination of the first cell by the terminal device; the time period information T4 between the determination of the first cell by the terminal device and the first access failure of the terminal device; the time period information T5 between the first access failure of the terminal device and the sending of the first message by the terminal device; and the time period information T2 between the RLF of the source SCG and the sending of the first message by the terminal device. As shown in FIG. 2, the first time period information can be T1, T3, T4, and T5. Alternatively, the first time period information can be T1, T2, T3, T4, and T5. Alternatively, it can also be other variants, which are not specifically limited.

[0128] ​In this scenario, the first message may also include cell information of the source PCell and / or source PSCell and / or the first cell and / or other candidate target primary and secondary cells except the first cell, wherein the cell information includes at least one of the following: PCI, frequency information, CGI, identification information (such as measurement identification, configuration identification). Optionally, the first message may also include the signal quality of the cell, such as when RLF occurs in the source SCG and the terminal device fails to access the first cell, the signal quality of at least one of the following cells: source PCell, source PSCell, first cell, candidate target primary and secondary cells except the first cell. The first message may also include indication information that RLF occurs in the source SCG. The first message may also include indication information that RLF does not occur in the source MCG. Optionally, the first message may also include indication information that the terminal device has received the first configuration information. Optionally, the first message may also include indication information that the terminal device has determined the first cell. Optionally, the first message may also include indication information that the terminal device has failed to access the first cell. Optionally, the first message may further include information of at least one candidate target primary and secondary cell and corresponding primary and secondary cell change execution condition information.

[0129] In this scenario, the first network device may be a source MN, or a network device providing communication for the terminal device. The second network device may be a network device to which the first cell belongs, or a source SN.

[0130] 3) The terminal device fails to access the first cell and RLF occurs in the source MCG.

[0131] In one implementation, if the terminal device fails to access the first cell and the source MCG has an RLF, such as Figure 7 As shown, the first time period information may include at least one of the following:

[0132] The time period information T1 between the terminal device receiving the first configuration information and the occurrence of RLF in the source SCG; the time period information T3 between the occurrence of RLF in the source SCG and the terminal device determining the first cell; the time period information T4 between the terminal device determining the first time period information and the occurrence of RLF in the source MCG; the time period information T5 between the occurrence of RLF in the source MCG and the failure of the terminal device to access the first cell; the time period information T6 between the failure of the terminal device to access the first cell and the sending of the first message by the terminal device; the time period information T2 between the occurrence of RLF in the source SCG and the sending of the first message by the terminal device. For example, the first time period information can be T1, T3, T4, T5 and T6. Or the first time period information can be T1, T2, T3, T4, T5 and T6. Or it can be other variations, which are not specifically limited.

[0133] In another implementation, if the terminal device fails to access the first cell and the source MCG has an RLF, such as Figure 8 As shown, the first time period information may include at least one of the following:

[0134] The time period information T1 from when the terminal device receives the first configuration information to when the source SCG has an RLF; the time period information T3 from when the source SCG has an RLF to when the terminal device determines the first cell; the time period information T4 from when the terminal device determines the first cell to when the terminal device fails to access the first cell; the time period information T5 from when the terminal device fails to access the first cell to when the source MCG has an RLF; the time period information T6 from when the source MCG has an RLF to when the terminal device sends the first message; the time period information T2 from when the source SCG has an RLF to when the terminal device sends the first message. For example, the first time period information can be T1, T3, T4, T5, and T6. Or the first time period information can be T1, T2, T3, T4, T5, and T6. Or it can be other variations, which are not specifically limited.

[0135] In this scenario, the first message may also include cell information of the source PCell and / or source PSCell and / or the first cell and / or other candidate target primary and secondary cells except the first cell, wherein the cell information includes at least one of the following: PCI, frequency information, CGI, identification information (such as measurement identification, configuration identification). Optionally, the first message may also include the signal quality of the cell, such as when the source SCG has an RLF, when the terminal device fails to access the first cell, or when the source MCG has an RLF, the signal quality of at least one of the following cells: source PCell, source PSCell, first cell, and candidate target primary and secondary cells except the first cell. The first message may also include indication information that the source SCG has an RLF. The first message may also include indication information that the source MCG has an RLF. Optionally, the first message may also include indication information that the terminal device has received the first configuration information. Optionally, the first message may also include indication information that the terminal device has determined the first cell. Optionally, the first message may also include indication information that the terminal device has failed to access the first cell. Optionally, the first message may further include information of at least one candidate target primary and secondary cell and corresponding primary and secondary cell change execution condition information.

[0136] In this scenario, the first network device may be a network device that provides communication for the terminal device. The second network device may be a network device to which the first cell belongs, or a source SN, or a source MN.

[0137] For the above several implementation manners, the first network device can send a second message to the second network device after receiving the first message. As shown in Figure 9 The exemplary flowchart for terminal device and network side communication can include the following steps:

[0138] Step 901: The terminal device determines the first cell according to the first configuration information and initiates access to the first cell.

[0139] The terminal device can determine the first cell satisfying the CPC change condition according to the first configuration information and initiate access to the first cell.

[0140] Step 902: If the terminal device successfully accesses the first cell, the terminal device sends a first message to the network device managing the first cell.

[0141] The network device managing the first cell can be the first network device. The content contained in the first message can refer to the foregoing. Alternatively, the terminal device can send the first message to the network device providing communication for the terminal device, and the terminal device is not limited to sending the first message to the network device to which the first cell belongs. If the CPC is triggered by the first network device, after receiving the first message, the first network device considers that the late CPC occurs, and can adjust the triggering time of the CPC, such as the time when the first network device sends the first configuration information to the terminal device in advance. Optionally, the first network device can also adjust the first configuration information, such as reducing the primary secondary cell change execution condition. If the CPC is triggered by the source SN, after receiving the first message, the first network device can send a second message to the source SN (i.e., the second network device), and the second message can contain part or all of the content in the first message. Optionally, the second message can also contain the indication information of the late CPC, i.e., the first information. After receiving the second message, the source SN can adjust the triggering time of the CPC, such as the time when the first configuration information is sent to the terminal device in advance. Optionally, the source SN can also adjust the first configuration information, such as reducing the primary secondary cell change execution condition.

[0142] Optionally, after receiving the second message, the candidate SN can send a third message to the source MN or the source SN, and the third message can include part or all of the second message. Optionally, the third message can include the second information indicating that the late CPC occurs.

[0143] Step 903: If the terminal device fails to access the first cell, and the source MCG occurs RLF, the terminal device initiates the RRC reestablishment process and performs step 904.

[0144] Step 904: The terminal device sends a first message to the network device to which the RRC reestablishment cell belongs.

[0145] The network device to which the RRC reestablishment cell belongs can be the first network device. Correspondingly, the RRC reestablishment cell can be different from the first cell and can be a cell managed by the first network device. Alternatively, the terminal device can send the first message to the network device providing communication for the terminal device, and the terminal device is not limited to sending the first message to only the network device to which the RRC reestablishment cell belongs. The content contained in the first message can refer to the foregoing.

[0146] After receiving the first message, the first network device can send a second message to the source MN and / or the source SN, so that the source MN or the source SN can adjust the trigger time of the CPC, such as the time of sending the first configuration information to the terminal device in advance. Optionally, the source MN or the source SN can also adjust the first configuration information, such as reducing the execution condition of the primary secondary cell change. Alternatively, the first network device can also send the second message to the candidate SN, and the candidate SN can adjust the first configuration information according to the second message, such as adjusting the information of the candidate target primary secondary cell. The second message can contain part or all of the content in the first message, and details are not described herein.

[0147] Step 905: If the terminal device fails to access the first cell and the source MCG does not have RLF, the terminal device sends a first message to the source MN.

[0148] The source MN can be the first network device. The first message can contain, for example, the following information: Figures 5-8The first time period information can be referred to the foregoing. Alternatively, the terminal device can send the first message to a network device providing communication for the terminal device, and the terminal device is not limited to sending the first message to the source MN only. If the CPC is triggered by the first network device, after receiving the first message, the first network device considers that the CPC occurs too late, and can adjust the triggering time of the CPC, such as the time when the first network device sends the first configuration information to the terminal device in advance. Optionally, the first network device can also adjust the first configuration information, such as reducing the execution condition of the primary secondary cell change. Alternatively, the first network device can send a second message to a candidate SN (such as a network device to which the first cell belongs, or a network device to which another candidate cell belongs), and the candidate SN can adjust the CPC parameters based on the second message, such as adjusting the information of the candidate target primary secondary cell. Alternatively, the first network device can release the source SN or replace the SCG / PSCell. If the CPC is triggered by the source SN, after receiving the first message, the first network device can send a second message to the source SN (i.e., the second network device), and the second message can include part or all of the content in the first message. Optionally, the second message can also include indication information of the too late CPC, and after receiving the second message, the source SN can adjust the triggering time of the CPC, such as the time when the first configuration information is sent to the terminal device in advance. Optionally, the source SN can also adjust the first configuration information, such as reducing the execution condition of the primary secondary cell change. Alternatively, the first network device can also send the second message to the candidate SN, and the candidate SN can adjust the first configuration information according to the second message, such as adjusting the information of the candidate target primary secondary cell. The second message can include part or all of the content in the first message, which will not be described herein.

[0149] Alternatively, after receiving the second message, the candidate SN can send a third message to the source MN or the source SN, and the third message can include part or all of the second message. Alternatively, the third message can include second information indicating that the CPC occurs too late.

[0150] Example three, before the RLF occurs in the source SCG or the source MCG, the terminal device determines the first cell.

[0151] If the terminal device determines the first cell before the RLF occurs in the source SCG or the source MCG, as Figure 10 indicated, the first time period information can include at least one of the following:

[0152] The terminal device receives time period information T1 from the start of receiving the first configuration information to the occurrence of RLF of the source SCG or the source MCG; the terminal device receives time period information T3 from the start of receiving the first configuration information to the determination of the first cell by the terminal device; the terminal device determines time period information T4 from the start of the first cell to the occurrence of RLF of the source MCG or the source SCG; and the terminal device determines time period information T2 from the start of the occurrence of RLF of the source SCG or the source MCG to the sending of the first message by the terminal device. For example, the first time period information can be T2, T3 and T4. Alternatively, the first time period information can be T1, T2, T3 and T4. Alternatively, other variations are also possible, which are not limited in particular.

[0153] In an implementation, if RLF of the source SCG or the source MCG occurs, even if the terminal device has determined the first cell, the terminal device does not access or stops accessing the first cell. The first message can further include cell information of the source PCell and / or the source PSCell and / or the first cell and / or other candidate target primary and secondary cells other than the first cell, wherein the cell information includes at least one of the following: PCI, frequency information, CGI, identification information (such as measurement identification, configuration identification). Optionally, the first message can further include signal quality of the cell, such as the signal quality of at least one of the following cells when RLF of the source SCG or the source MCG occurs: the source PCell, the source PSCell, the first cell, and the candidate target primary and secondary cells other than the first cell. The first message can further include indication information of the occurrence of RLF of the source SCG or the source MCG. Optionally, the first message can further include indication information of the receiving of the first configuration information by the terminal device. Optionally, the first message can further include indication information of the determination of the first cell by the terminal device. Optionally, the first message can further include indication information of the non-access or stop of access of the first cell by the terminal device. Optionally, the first message can further include information of at least one candidate target primary and secondary cell and corresponding primary and secondary cell change execution condition information.

[0154] If the CPC is initiated by the source MN and the source SCG has an RLF, then the first network device may be the source MN, and the second network device may be the source SN or a candidate SN (such as the network device to which the first cell belongs, or the network device to which other candidate cells belong). The source MN can determine that a late CPC has occurred based on the first message, so the second message may also include the first information indicating that a late CPC has occurred. The source MN may adjust the triggering time of the CPC, such as advancing the time of sending the first configuration information to the terminal device. Optionally, the source MN may also adjust the first configuration information, such as lowering the execution conditions for the primary and secondary cell changes. Optionally, the source MN may send a second message to the candidate SN, and the candidate SN may adjust the CPC parameters based on the second message, such as adjusting the information of the candidate target primary and secondary cells. Optionally, the source MN may also release the source SN, or replace the SCG / PSCell.

[0155] If the CPC is initiated by the source SN and the source SCG has an RLF, then the first network device may be the source MN, and the second network device may be the source SN or a candidate SN (such as the network device to which the first cell belongs, or the network device to which other candidate cells belong). Optionally, after receiving the first message, the source MN may release the source SN, or may replace the SCG / PSCell. The replaced SCG / PSCell may or may not belong to the source SN. The second message may be sent to the source SN and the candidate SN. Alternatively, the source MN may send the second message to the source SN, and the source SN then forwards the received second message to the candidate SN. The second message may include part or all of the content in the first message. Optionally, the second message may also include indication information of a late CPC. After receiving the second message, the source SN determines that a late CPC has occurred and may adjust the CPC triggering time, such as advancing the time for sending the first configuration information to the terminal device. Optionally, the source SN may also adjust the first configuration information, such as lowering the execution conditions for the primary and secondary cell changes. Optionally, the candidate SN may adjust the first configuration information based on the received second message, such as adjusting the information of the candidate target primary and secondary cells.

[0156] In another implementation, if the source SCG or source MCG has an RLF, the terminal device has already determined the first cell, and the terminal device starts or continues to initiate access to the first cell. Depending on whether the terminal device successfully accesses the first cell, the first time period information may also be different, and may include the following two situations:

[0157] 1) The terminal device successfully accesses the first cell.

[0158] If the terminal device successfully accesses the first cell, such as Figure 11 As shown, the first time period information may include at least one of the following:

[0159] The time period information T1 between the time when the terminal device receives the first configuration information and the time when the source SCG or source MCG has an RLF; the time period information T3 between the time when the terminal device receives the first configuration information and the time when the first cell is determined; the time period information T4 between the time when the first cell is determined and the time when the source MCG or source SCG has an RLF; the time period information T5 between the time when the source MCG or source SCG has an RLF and the time when the terminal device accesses the first cell; the time period information T6 between the time when the terminal device accesses the first cell and the time when the terminal device sends the first message; the time period information T2 between the time when the source SCG or source MCG has an RLF and the time when the terminal device sends the first message. For example, the first time period information can be T1, T3, T4, T5 and T6, or the first time period information can also be T1, T2, T3, T4, T5 and T6. Alternatively, the first time period information can be T1, T2, T3, T4, T5 and T6. Or it can be other variations, which are not specifically limited.

[0160] The first message may also include cell information of the source PCell and / or source PSCell and / or the first cell and / or other candidate target primary and secondary cells other than the first cell, wherein the cell information includes at least one of the following: PCI, frequency information, CGI, and identification information (such as a measurement identifier and a configuration identifier). Optionally, the first message may also include cell signal quality, such as the signal quality of at least one of the following cells: the source PCell, the source PSCell, the first cell, and candidate target primary and secondary cells other than the first cell when an RLF occurs in the source SCG or the source MCG and the terminal device successfully accesses the first cell. The first message may also include indication information that the source SCG or the source MCG has experienced an RLF. Optionally, the first message may also include indication information that the terminal device has received the first configuration information. Optionally, the first message may also include indication information that the terminal device has determined the first cell. Optionally, the first message may also include indication information that the terminal device has started or continued access to the first cell after an RLF occurs in the SCG or the source MCG. Optionally, the first message may also include indication information that the terminal device has successfully accessed the first cell. Optionally, the first message may further include information of at least one candidate target primary and secondary cell and corresponding primary and secondary cell change execution condition information.

[0161] After successfully accessing the first cell, the terminal device may send the first message to the network device that manages the first cell. Accordingly, the network device that manages the first cell may be the aforementioned first network device. After receiving the first message from the terminal device, the first network device may also send a second message to the second network device. Figure 12 FIG. 1 is an exemplary flow chart of communication between a terminal device and a first network device, which may include the following steps:

[0162] Step 1201: The terminal device sends a first message to the first network device.

[0163] The first network device may be a network device that manages the first cell. The content of the first message here may refer to the above. Alternatively, the terminal device may send the first message to a network device that provides communication for the terminal device, and the terminal device is not limited to sending the first message only to the network device to which the first cell belongs.

[0164] If the CPC is triggered by the first network device, then, after receiving the first message, the first network device considers that the CPC occurs too late and can adjust the CPC triggering time, such as the time when the first network device sends the first configuration information to the terminal device in advance. Optionally, the first network device can also adjust the first configuration information, such as lowering the execution conditions for the primary and secondary cell changes. If the CPC is triggered by the source MN, then, after receiving the first message, the first network device can send a second message to the source MN, and the second message can include part or all of the content in the first message. Optionally, the second message can also include indication information of too late CPC. After receiving the second message, the source MN can adjust the CPC triggering time, such as the time when the first configuration information is sent to the terminal device in advance. Optionally, the source MN can also adjust the first configuration information, such as lowering the execution conditions for the primary and secondary cell changes.

[0165] Step 1202: The network device managing the first cell sends a second message to the second network device.

[0166] The second network device here can be the source MN or the candidate SN. For example, the network device managing the first cell can send a second message to the source MN and the candidate SN; or the network device managing the first cell can send a second message to the source MN. After receiving the second message, the source MN can reconfigure the MN, for example, by replacing the MCG / PCell, which may or may not belong to the source MN. The candidate SN can adjust CPC parameters based on the second message, for example, by adjusting information about the candidate target primary and secondary cells.

[0167] Optionally, after receiving the second message, the candidate SN may send a third message to the source MN or source SN, where the third message may include part or all of the second message. Optionally, the third message may include second information, where the second information indicates that late CPC occurs.

[0168] 2) The terminal device fails to access the first cell.

[0169] If the terminal device fails to access the first cell, the first time period information can be different according to the first cell determined before the RLF of the source SCG or before the RLF of the source MCG. In the following, different first time period information is introduced respectively.

[0170] (1) Before the RLF of the source MCG, the terminal device determines the first cell and fails to access the first cell, and the source SCG does not have RLF.

[0171] As shown in the first time period information can include at least one of the following: Figure 13

[0172] The time period information T1 between the time when the terminal device receives the first configuration information and the RLF of the source MCG; the time period information T3 between the time when the terminal device receives the first configuration information and the time when the first cell is determined; the time period information T4 between the time when the first cell is determined and the RLF of the source MCG; the time period information T5 between the time when the RLF of the source MCG occurs and the time when the terminal device fails to access the first cell; the time period information T6 between the time when the terminal device fails to access the first cell and the time when the terminal device sends the first message; the time period information T2 between the time when the RLF of the source MCG occurs and the time when the terminal device sends the first message. For example, the first time period information can be T3, T4, T5, T6, or the first time period information can be T1, T2, T3, T4, T5 and T6. Or other variations, not limited.

[0173] (2) Before the RLF of the source MCG, the terminal device determines the first cell and fails to access the first cell, and the source SCG has RLF.

[0174] In an embodiment, as shown in the first time period information can include at least one of the following: Figure 14

[0175] ​​The terminal device receives time period information T1 from the start of receiving the first configuration information to the occurrence of the RLF of the source MCG; receives time period information T3 from the start of receiving the first configuration information to the determination of the first cell; receives time period information T4 from the start of the determination of the first cell to the occurrence of the RLF of the source MCG; receives time period information T5 from the start of the occurrence of the RLF of the source MCG to the access failure of the terminal device to the first cell; receives time period information T6 from the start of the access failure of the terminal device to the first cell to the occurrence of the RLF of the source SCG; receives time period information T7 from the start of the occurrence of the RLF of the source SCG to the sending of the first message by the terminal device; and receives time period information T2 from the start of the occurrence of the RLF of the source MCG to the sending of the first message by the terminal device. For example, the first time period information can be T3, T4, T5, T6, and T7, or the first time period information can be T1, T2, T3, T4, T5, T6, and T7. Or other variations, not limited.

[0176] In another embodiment, as shown in FIG. 16, the first time period information can include at least one of the following: Figure 15

[0177] The terminal device receives time period information T1 from the start of receiving the first configuration information to the occurrence of the RLF of the source MCG; receives time period information T3 from the start of receiving the first configuration information to the determination of the first cell; receives time period information T4 from the start of the determination of the first cell to the occurrence of the RLF of the source MCG; receives time period information T5 from the start of the occurrence of the RLF of the source MCG to the access failure of the terminal device to the first cell; receives time period information T6 from the start of the access failure of the terminal device to the first cell to the occurrence of the RLF of the source SCG; receives time period information T7 from the start of the occurrence of the RLF of the source SCG to the sending of the first message by the terminal device; and receives time period information T2 from the start of the occurrence of the RLF of the source MCG to the sending of the first message by the terminal device. For example, the first time period information can be T3, T4, T5, T6, and T7, or the first time period information can be T1, T2, T3, T4, T5, T6, and T7. Or other variations, not limited.

[0178] After receiving the first message from the terminal device, the first network device can send a second message to the second network device. As shown in FIG. 17, an exemplary flowchart for the terminal device to communicate with the network side can include the following steps: Figure 16

[0179] Step 1601: After determining the first cell, the source MCG occurs RLF, and the terminal device initiates access to the first cell.

[0180] Step 1602: If the terminal device successfully accesses the first cell, the terminal device sends the first message to the first network device.

[0181] ​​Here, the first network device can be a network device managing the first cell, and the second network device can be a source MN or a candidate SN. Alternatively, the terminal device can send the first message to a network device providing communication for the terminal device, and it is not limited that the terminal device only sends the first message to a network device to which the first cell belongs. For example, the first network device can send a second message to the source MN. The second message can be part or all of the first message. For example, the second message can include the first time period information as shown in Figures 13-15 The source MN can change the MCG / PSCell, and the changed MCG / PSCell can or can not belong to the source MN. Optionally, if the CPC is triggered by the source MN, the source MN can adjust the triggering time of the CPC, such as the time of sending the first configuration information to the terminal device in advance. Optionally, the source MN can also adjust the first configuration information, such as reducing the execution condition of the primary and secondary cell change. The first network device can also send the second message to the source SN or the candidate SN, or the source MN can send the second message to the source SN or the candidate SN after receiving the second message. After receiving the second message, if the CPC is triggered by the source SN, the source SN can adjust the triggering time of the CPC, such as the time of sending the first configuration information to the terminal device in advance. Optionally, the source SN can also adjust the first configuration information, such as reducing the execution condition of the primary and secondary cell change. On the other hand, the candidate SN can adjust the CPC parameters after receiving the second message, for example, the information of the candidate target primary and secondary cell can be adjusted.

[0182] Step 1603: If the terminal device fails to access the first cell, and the source SCG does not have RLF, the first message is sent to the first network device.

[0183] At this time, the first network device can be a source SN, and the second network device can be a source MN or a candidate SN. Alternatively, the terminal device can send the first message to a network device providing communication for the terminal device, and it is not limited that the terminal device only sends the first message to the source SN. If the CPC is triggered by the source SN, the source SN can adjust the triggering time of the CPC, such as the time of sending the first configuration information to the terminal device in advance. Optionally, the source SN can also adjust the first configuration information, such as reducing the execution condition of the primary and secondary cell change. Optionally, the source SN can send a second message to the source MN. The second message here can include part or all of the first message, for example, the second message can include the first time period information as shown in Figures 13-15For the first time period information shown, please refer to the above text for details. The source MN can change the MCG / PSCell, and the changed MCG / PSCell may belong to or not belong to the source MN. Optionally, if the CPC is triggered by the source MN, the source MN can adjust the triggering time of the CPC, such as advancing the time of sending the first configuration information to the terminal device. Optionally, the source MN can also adjust the first configuration information, such as lowering the execution conditions for the primary and secondary cell changes. Optionally, the source SN can also send a second message to the candidate SN, or the source MN can send the second message to the candidate SN. After receiving the second message, the candidate SN can adjust the CPC parameters, for example, it can adjust the information of the candidate target primary and secondary cells. Optionally, after receiving the second message, the candidate SN can send a third message to the source MN or source SN. The third message may include part or all of the second message. Optionally, the third message may include second information, and the second information indicates that a late CPC occurs.

[0184] Step 1604: If the terminal device fails to access the first cell and RLF occurs in the source SCG, the terminal device re-establishes the RRC connection.

[0185] Step 1605: The terminal device sends a first message to the first network device.

[0186] Among them, the aforementioned first network device can be the network device that manages cell A, and the second network device can be the source MN or the candidate SN. The cell A here is the cell that the terminal device accesses to re-establish the RRC connection, which can be different from the first cell. Alternatively, the terminal device can send a first message to the network device that provides communication for the terminal device, and it is not limited that the terminal device can only send the first message to the network device to which cell A belongs. The network device that manages cell A or the first network device can send a second message to the source MN, source SN or candidate SN. The second message here can include part or all of the first message. For example, the second message can include the following: Figures 13-15The first time period information is shown. Alternatively, the network device managing the cell A can send a second message to the source MN, and the source MN can send the second message to the source SN or the candidate SN. Alternatively, after receiving the second message, the source MN can change the MCG / PSCell, and the changed MCG / PSCell can belong to or not belong to the source MN. Alternatively, if the CPC is triggered by the source MN, the source MN can adjust the triggering time of the CPC, such as the time of sending the first configuration information to the terminal device in advance. Alternatively, the source MN can also adjust the first configuration information, such as reducing the execution condition of the primary secondary cell change. Alternatively, after receiving the second message, if the CPC is triggered by the source SN, the source SN can adjust the triggering time of the CPC, such as the time of sending the first configuration information to the terminal device in advance. Alternatively, the source SN can also adjust the first configuration information, such as reducing the execution condition of the primary secondary cell change. Alternatively, after receiving the second message, the candidate SN can adjust the CPC parameters, for example, the information of the candidate target primary secondary cell.

[0187] Alternatively, after receiving the second message, the candidate SN can send a third message to the source MN or the source SN, and the third message can include part or all of the second message. Alternatively, the third message can include second information indicating that the too-late CPC occurs.

[0188] (3) Before the RLF of the source SCG occurs, the terminal device determines the first cell, and fails to access the first cell, and the source MCG does not have the RLF.

[0189] If the terminal device fails to access the first cell, and the source MCG does not have the RLF, as shown in Figure 17 The first time period information can include at least one of the following:

[0190] The time period information T1 between the time when the terminal device receives the first configuration information and the time when the RLF of the source SCG occurs; the time period information T3 between the time when the terminal device receives the first configuration information and the time when the first cell is determined; the time period information T4 between the time when the first cell is determined and the time when the RLF of the source SCG occurs; the time period information T5 between the time when the RLF of the source SCG occurs and the time when the terminal device fails to access the first cell; the time period information T6 between the time when the terminal device fails to access the first cell and the time when the terminal device sends the first message; and the time period information T2 between the time when the RLF of the source SCG occurs and the time when the terminal device sends the first message. For example, the first time period information can be T3, T4, T5 and T6, or the first time period information can also be T1, T2, T3, T4, T5 and T6. Alternatively, other modifications are not limited.

[0191] (4) before the RLF of the source SCG, the terminal device determines the first cell and fails to access the first cell, and the RLF of the source MCG occurs.

[0192] In one embodiment, if the terminal device fails to access the first cell and the RLF of the source MCG occurs, the first time period information can include at least one of the following, as shown in Figure 18

[0193] The time period information T1 from when the terminal device receives the first configuration information to when the RLF of the source SCG occurs; the time period information T3 from when the terminal device receives the first configuration information to when the first cell is determined; the time period information T4 from when the first cell is determined to when the RLF of the source SCG occurs; the time period information T5 from when the RLF of the source SCG occurs to when the terminal device fails to access the first cell; the time period information T6 from when the terminal device fails to access the first cell to when the RLF of the source MCG occurs; the time period information T7 from when the RLF of the source MCG occurs to when the terminal device sends the first message; and the time period information T2 from when the RLF of the source SCG occurs to when the terminal device sends the first message. For example, the first time period information can be T3, T4, T5, T6, and T7, or the first time period information can be T1, T2, T3, T4, T5, T6, and T7. Or other variations are not limited.

[0194] In another embodiment, if the terminal device fails to access the first cell and the RLF of the source MCG occurs, the first time period information can include at least one of the following, as shown in Figure 19

[0195] The time period information T1 from when the terminal device receives the first configuration information to when the RLF of the source SCG occurs; the time period information T3 from when the terminal device receives the first configuration information to when the first cell is determined; the time period information T4 from when the first cell is determined to when the RLF of the source SCG occurs; the time period information T5 from when the RLF of the source SCG occurs to when the terminal device fails to access the first cell; the time period information T6 from when the terminal device fails to access the first cell to when the RLF of the source MCG occurs; the time period information T7 from when the RLF of the source MCG occurs to when the terminal device sends the first message; and the time period information T2 from when the RLF of the source SCG occurs to when the terminal device sends the first message. For example, the first time period information can be T3, T4, T5, T6, and T7, or the first time period information can be T1, T2, T3, T4, T5, T6, and T7. Or other variations are not limited.

[0196] ​​After receiving the first message from the terminal device, the first network device may send a second message to the second network device. Figure 20 FIG. 1 is an exemplary flow chart of communication between a terminal device and a network side, which may include the following steps:

[0197] Step 2001: After determining the first cell, RLF occurs in the source SCG, and the terminal device initiates access to the first cell.

[0198] Step 2002: If the terminal device successfully accesses the first cell, the terminal device sends a first message to the first network device.

[0199] Here, the first network device can be a network device that manages the first cell, and the second network device can be a source MN or a candidate SN. Alternatively, the terminal device can send a first message to a network device that provides communication for the terminal device, and the terminal device is not limited to sending the first message only to the network device to which the first cell belongs. The network device that manages the first cell can send a second message to the source MN. The second message can include part or all of the first message. For example, the second message can include Figures 17-19 The first time period information shown. Optionally, after the source MN receives the second message, it can change the MCG / PSCell. The changed MCG / PSCell may belong to or not belong to the source MN. Optionally, if the CPC is triggered by the source MN, the source MN can adjust the triggering time of the CPC, such as the time of sending the first configuration information to the terminal device in advance. Optionally, the source MN can also adjust the first configuration information, such as lowering the execution conditions for the change of the primary and secondary cells. The network device that manages the first cell can also send the second message to the source SN or the candidate SN, or the source MN can send the second message to the source SN or the candidate SN after receiving the second message. If the CPC is triggered by the source SN, the source SN can adjust the triggering time of the CPC after receiving the second message, such as the time of sending the first configuration information to the terminal device in advance. Optionally, the source SN can also adjust the first configuration information, such as lowering the execution conditions for the change of the primary and secondary cells. After receiving the second message, the candidate SN can adjust the CPC parameters, for example, it can adjust the information of the candidate target primary and secondary cells.

[0200] Step 2003: If the terminal device fails to access the first cell and RLF does not occur in the source MCG, the first message is sent to the first network device.

[0201] At this time, the first network device can be a source MN, and the second network device can be a source SN or a candidate SN. Alternatively, the terminal device can send the first message to a network device providing communication for the terminal device, and it is not limited that the terminal device only sends the first message to the source MN. The source MN can send the second message to the source SN or the candidate SN. The second message can include part or all of the first message. For example, the second message can include the first time period information as shown in Figures 17-19 Optionally, after receiving the first message, the source MN can change the MCG / PSCell, and the changed MCG / PSCell can or can not belong to the source MN. Optionally, if the CPC is triggered by the source MN, the source MN can adjust the triggering time of the CPC, such as the time of sending the first configuration information to the terminal device in advance. Optionally, the source MN can also adjust the first configuration information, such as reducing the execution condition of the primary / secondary cell change. The source MN can also send the second message to the source SN or the candidate SN, or the source SN can send the second message to the candidate SN after receiving the second message. Optionally, after receiving the second message, if the CPC is triggered by the source SN, the source SN can adjust the triggering time of the CPC, such as the time of sending the first configuration information to the terminal device in advance. Optionally, the source SN can also adjust the first configuration information, such as reducing the execution condition of the primary / secondary cell change. Optionally, after receiving the second message, the candidate SN can adjust the CPC parameters, for example, the information of the candidate target primary / secondary cell.

[0202] Optionally, after receiving the second message, the candidate SN can send a third message to the source MN or the source SN, and the third message can include part or all of the second message. Optionally, the third message can include second information indicating that the too-late CPC occurs.

[0203] Step 2004: If the terminal device fails to access the first cell and the source MCG experiences RLF, the terminal device re-establishes the RRC connection.

[0204] Step 2005: The terminal device sends a first message to the first network device.

[0205] The first network device can be a network device managing the cell A, and the second network device can be a source MN or a candidate SN. Here, the cell A can be a cell accessed by the terminal device after re-establishing the RRC connection, and can be different from the first cell. Alternatively, the terminal device can send the first message to a network device providing communication for the terminal device, and it is not limited that the terminal device only sends the first message to the network device to which the cell A belongs. The network device managing the cell A can send a second message to the source MN, the source SN or the candidate SN. The second message can include part or all of the first message. For example, the second message can include the first time period information as shown in Figures 17-19The first time period information can include at least one of the following: a time period T3 from when the terminal device receives the first configuration information to when the terminal device determines the time period information between the first cells; a time period T4 from when the terminal device determines the first cells to when the terminal device successfully accesses the first cells; a time period T5 from when the terminal device successfully accesses the first cells to when the source MCG or the source SCG experiences the RLF; a time period T1 from when the terminal device receives the first configuration information to when the source MCG or the source SCG experiences the RLF; and a time period T2 from when the source MCG or the source SCG experiences the RLF to when the terminal device sends the first message. For example, the first time period information can include T3, T4 and T5, or the first time period information can include T1, T2, T3, T4 and T5. Alternatively, other variations are not limited.

[0206] Alternatively, the candidate SN, after receiving the second message, can send a third message to the source MN or the source SN, the third message can include part or all of the second message, and the third message can include second information indicating that the too-late CPC occurs.

[0207] Example four, after the terminal device successfully accesses the first cells, the source MCG or the source SCG experiences the RLF.

[0208] If, after the terminal device successfully accesses the first cells, the source MCG or the source SCG experiences the RLF, as Figure 21 indicated, the first time period information can include at least one of the following:

[0209] The terminal device receives the first configuration information to determine the time period information T3 between the first cells; the terminal device determines the first cells to successfully access the first cells between the time period information T4; the terminal device successfully accesses the first cells to the source MCG or the source SCG experiences the RLF between the time period information T5; the terminal device receives the first configuration information to the source MCG or the source SCG experiences the RLF between the time period information T1; the source MCG or the source SCG experiences the RLF to the terminal device sends the first message between the time period information T2. For example, the first time period information can include T3, T4 and T5, or the first time period information can include T1, T2, T3, T4 and T5. Alternatively, other variations are not limited.

[0210] The first network device, after receiving the first message, can also send a second message to the second network device. As Figure 22As shown, an exemplary flowchart of the terminal device and the network side signaling can include the following steps:

[0211] Step 2201: The terminal device sends a first message to the first network device.

[0212] Here, the first network device can be a network device managing the first cell. Alternatively, the terminal device can send the first message to the network device providing communication for the terminal device, and it is not limited that the terminal device can only send the first message to the network device to which the first cell belongs. The first message can include, for example, Figure 21 the first time period information as shown.

[0213] Step 2202: The first network device can send a second message to the second network device.

[0214] Here, the second network device can be at least one of the source MN, the source SN and the candidate SN.

[0215] In an implementation manner, if the source MCG occurs RLF after accessing the first cell, the network device managing the first cell can send the second message to the source MN, and if the source SCG occurs RLF after accessing the first cell, the network device managing the first cell can send the second message to the source SN. Alternatively, the network device managing the first cell can also send the second message to the source SN and the candidate SN, or the source MN can send the second message to the source SN, or the source MN or the source SN can send the second message to the candidate SN. Alternatively, after receiving the second message, the source MN can change the MCG / PSCell, and the changed MCG / PSCell can or can not belong to the source MN. Alternatively, if the CPC is triggered by the source MN, the source MN can adjust the triggering time of the CPC, such as the time of sending the first configuration information to the terminal device in advance. Alternatively, the source MN can also adjust the first configuration information, such as reducing the execution condition of the primary / secondary cell change. Alternatively, after receiving the second message, if the CPC is triggered by the source SN, the source SN can adjust the triggering time of the CPC, such as the time of sending the first configuration information to the terminal device in advance. Alternatively, the source SN can also adjust the first configuration information, such as reducing the execution condition of the primary / secondary cell change. Alternatively, after receiving the second message, the candidate SN can adjust the CPC parameters, for example, the information of the candidate target primary / secondary cell.

[0216] Alternatively, after receiving the second message, the candidate SN can send a third message to the source MN or the source SN, and the third message can include part or all of the second message. Alternatively, the third message can include second information indicating that the late CPC occurs.

[0217] The second message here may include part or all of the first message. For example, the second message may include Figure 21 The first time period information is shown.

[0218] As described in Examples 1 to 4, the terminal device may send a first message to the first network device. The first message may include first time period information. In one embodiment, the terminal device may also send first indication information to the first network device. The first indication information may indicate that an RLF has occurred in the source MCG or the source SCG. Exemplarily, the terminal device may send the first message and the first indication information separately, or may carry the first indication information in the first message and send it.

[0219] If RLF occurs in the source MCG, the first indication information is used to indicate that RLF occurs in the source MCG. If RLF occurs in the source SCG, the first indication information is used to indicate that RLF occurs in the source SCG.

[0220] In one example, the first message may also include the cell information of the source MCG. The source MCG may include the source PCell, and optionally also include the source SCell belonging to the source MN. The cell information of the source MCG may include the identification information of the source MCG. For example, at least one of the PCI of the source MCG, the frequency of the source MCG, and the CGI of the source MCG. Alternatively, the cell information of the source MCG may also include the signal quality of the cell. For example, it may include the cell signal quality of the source MCG when the terminal device has an RLF in the source SCG. It may also include the cell signal quality of the source MCG when the terminal device has an RLF in the source MCG. It may also include the cell signal quality of the source MCG when the terminal device sends the first message. It may also include the cell signal quality of the source MCG when the terminal device determines the first cell. Alternatively, it may also include the cell signal quality of the source MCG when the terminal device successfully accesses the first cell. Alternatively, it may also include the cell signal quality of the source MCG when the terminal device fails to access the first cell.

[0221] In another example, the first message can further comprise cell information of the source SCG. The source SCG can comprise a source PSCell, and optionally further comprise a source SCell belonging to the source SN. The cell information of the source SCG can comprise identification information of the source SCG. For example, at least one of a PCI of the source SCG, a frequency of the source SCG, and a CGI of the source SCG. Alternatively, the cell information of the source SCG can further comprise cell signal quality. For example, the cell signal quality of the source SCG when the RLF of the source MCG occurs can be comprised. The cell signal quality of the source SCG when the RLF of the source SCG occurs can also be comprised. Alternatively, the cell signal quality of the source SCG when the first message is sent can also be comprised. The cell signal quality of the source SCG when the first cell is determined can also be comprised. Alternatively, the cell signal quality of the source SCG when the access to the first cell is successful can also be comprised. Alternatively, the cell signal quality of the source SCG when the access to the first cell fails can also be comprised.

[0222] In yet another example, the first message can further comprise cell information of at least one candidate target primary secondary cell. The cell information of the at least one candidate target cell can comprise the cell information of the first cell, or further comprise cell information of other candidate target primary secondary cells in addition to the first cell. For example, identification information of the at least one candidate target primary secondary cell can be comprised. For example, at least one of a PCI, a frequency, and a CGI can be comprised. Alternatively, the cell signal quality of the at least one candidate target primary secondary cell can also be comprised. For example, the cell signal quality of the at least one candidate target primary secondary cell when the RLF of the source MCG or the RLF of the source SCG occurs can be comprised. Alternatively, the cell signal quality of the at least one candidate target primary secondary cell when the first message is sent can also be comprised. The cell signal quality of the at least one candidate target primary secondary cell when the first cell is determined can also be comprised. Alternatively, the cell signal quality of the at least one candidate target primary secondary cell when the access to the first cell is successful can also be comprised. Alternatively, the cell signal quality of the at least one candidate target primary secondary cell when the access to the first cell fails can also be comprised.

[0223] It should be understood that the second message can contain part or all of the first message. Therefore, the second message can also contain at least one of the above-mentioned first information, cell information of the source MCG, cell information of the source SCG, and cell information of the at least one candidate target primary secondary cell. For example, the first information and the cell information of the source MCG can be contained in the second message. Alternatively, the first information and the cell information of the source SCG can be contained in the second message. Alternatively, the first information and the cell information of the at least one candidate target primary secondary cell can be contained in the second message. Alternatively, the first information, the cell information of the source MCG, the cell information of the source SCG, and the cell information of the at least one candidate target primary secondary cell can be contained in the second message. Or others, the present application does not limit this.

[0224] Based on the above scheme, through the cell information of the source MCG, the cell information of the source SCG, and the cell information of the at least one candidate target primary secondary cell contained in the second message, the network device can determine the cause of the primary secondary cell change failure according to the above information, and the network devices can also interact reasonable and effective information, so that the configuration information of the primary secondary cell change can be optimized accordingly, and the success rate of the primary secondary cell change can be improved.

[0225] The foregoing introduces the communication method of the embodiments of the present application, and the following introduces the communication device in the embodiments of the present application. The method and the device are based on the same technical concept, and since the principles of the method and the device for solving problems are similar, the implementation of the device and the method can be referred to each other, and the repeated parts will not be described herein.

[0226] Based on the same technical concept as the above communication method, as shown in Figure 23 a terminal device 2300 is provided. The terminal device 2300 can perform each step in the above method performed by the terminal device, and to avoid repetition, details are not described herein. The terminal device 2300 comprises a communication unit 2310, a storage unit 2330, and optionally a processing unit 2320; the processing unit 2320 can be connected to the storage unit 2330 and the communication unit 2310 respectively, and the storage unit 2330 can also be connected to the communication unit 2310. The processing unit 2320 can be integrated with the storage unit 2330.

[0227] The storage unit 2330 is configured to store a computer program.

[0228] The communication unit 2310 is configured to receive first configuration information. The first configuration information includes information of at least one candidate target primary secondary cell and corresponding primary secondary cell change execution condition information. The first configuration information is used to determine a first cell. The first cell is a cell in the at least one candidate target primary secondary cell that satisfies the primary secondary cell change execution condition. The communication unit 2310 is configured to send a first message when a radio link failure (RLF) occurs in a source master cell group (MCG) or a source secondary cell group (SCG) of the terminal device. The first message includes first time period information. For details of the first time period information, refer to the description of the method embodiment as shown in Figure 2

[0229] The embodiment of the present application further provides a communication apparatus. The communication apparatus can be a terminal device or a circuit. The communication apparatus can be used to perform the actions performed by the terminal device in the above method embodiments.

[0230] The steps performed by the terminal device in the above method can also be implemented by a chip for the terminal device. The communication unit can be an input / output circuit or an interface of the chip. The processing unit can be a logic circuit. The logic circuit can process the to-be-processed data according to the steps described in the above method aspects, and obtain processed data. The to-be-processed data can be data received by the input circuit / interface, such as the first configuration information. The processed data can be data obtained according to the to-be-processed data, such as the first message. The output circuit / interface is configured to output the processed data.

[0231] Figure 24 A simplified structure diagram of a terminal device is shown. This is for the convenience of understanding and illustration, Figure 24 The terminal device is taken as an example of a mobile phone. Figure 24 As shown in the figure, the terminal device includes a processor, a memory, a radio frequency circuit, an antenna, and an input / output device. The processor is mainly used to process communication protocols and communication data, control the terminal device, execute software programs, process data of the software programs, and the like. The memory is mainly used to store software programs and data. The radio frequency circuit is mainly used to convert baseband signals and radio frequency signals and process radio frequency signals. The antenna is mainly used to transceive radio frequency signals in the form of electromagnetic waves. The input / output device, such as a touch screen, a display screen, a keyboard, and the like, is mainly used to receive data input by a user and output data to the user. It should be noted that some types of terminal devices can not have an input / output device.

[0232] ​When data needs to be sent, the processor performs baseband processing on the data to be sent and outputs the baseband signal to the RF circuit. The RF circuit performs RF processing on the baseband signal and then transmits the RF signal to the outside in the form of electromagnetic waves through the antenna. When data is sent to the terminal device, the RF circuit receives the RF signal through the antenna, converts the RF signal into a baseband signal, and outputs the baseband signal to the processor. The processor converts the baseband signal into data and processes the data. For the sake of explanation, Figure 24 Only one memory and processor are shown. In actual terminal device products, one or more processors and one or more memories may exist. Memory may also be referred to as a storage medium or storage device. The memory may be provided independently of the processor or integrated with the processor, and this is not limited in the embodiments of the present application.

[0233] In the embodiment of the present application, the antenna and radio frequency circuit with transceiver functions can be regarded as the communication unit of the terminal device, and the processor with processing function can be regarded as the processing unit of the terminal device. Figure 24 As shown, the terminal device includes a communication unit 2410 and a processing unit 2420. The communication unit may also be referred to as a transceiver, transceiver, or transceiver device. The processing unit may also be referred to as a processor, processing board, processing module, or processing device. Optionally, the device in the communication unit 2410 that implements the receiving function may be considered a receiving unit, and the device in the communication unit 2410 that implements the transmitting function may be considered a transmitting unit, i.e., the communication unit 2410 includes a receiving unit and a transmitting unit. The communication unit may also be referred to as a transceiver, transceiver, or transceiver circuit. The receiving unit may also be referred to as a receiver, receiver, or receiving circuit. The transmitting unit may also be referred to as a transmitter, transmitter, or transmitting circuit.

[0234] It should be understood that the communication unit 2410 is used to perform sending and receiving operations on the terminal device side in the above method embodiment, and the processing unit 2420 is used to perform other operations on the terminal device except sending and receiving operations in the above method embodiment.

[0235] For example, in one implementation, the communication unit 2410 is used to perform Figure 2 The receiving and / or sending operations on the terminal device side in steps 201 and 202, and / or the communication unit 2410 is also used to perform other receiving and sending steps on the terminal device side in the embodiment of the present application. The processing unit 2420 is used to perform other processing steps on the terminal device side in the embodiment of the present application.

[0236] Based on the same technical concept as the above communication method, Figure 25As shown, a network device 2500 is provided. The network device 2500 can perform the steps in the above method by the first network device or the second network device, and details are not repeated here. The network device 2500 comprises a communication unit 2510, a storage unit 2530, and optionally a processing unit 2520; the processing unit 2520 can be connected to the storage unit 2530 and the communication unit 2510 respectively, and the storage unit 2530 can also be connected to the communication unit 2510. The processing unit 2520 can be integrated with the storage unit 2530.

[0237] The storage unit 2530 is configured to store a computer program.

[0238] For example, the communication unit 2510 is configured to receive the first message sent by the terminal device. The description of the first message can be referred to the related description in the method embodiments as shown in the above. Figure 2 The communication unit 2510 is also configured to send a second message to the second network device. The description of the second message can be referred to the related description in the method embodiments as shown in the above. Figure 2 The communication unit 2510 is also configured to send a second message to the second network device. The description of the second message can be referred to the related description in the method embodiments as shown in the above.

[0239] For example, the communication unit 2510 can also receive the second message sent by the first network device, and send a third message to the third network device. The description of the third message can be referred to the related description in the method embodiments as shown in the above. Figure 2 For example, the communication unit 2510 can also receive the second message sent by the first network device, and send a third message to the third network device. The description of the third message can be referred to the related description in the method embodiments as shown in the above.

[0240] The steps in the above method performed by the first network device or the second network device can also be implemented by a chip for a network device, wherein the communication unit can be an input / output circuit or an interface of the chip, the processing unit can be a logic circuit, the logic circuit can process the to-be-processed data according to the steps described in the above method aspects to obtain processed data. The to-be-processed data can be data received by the input circuit / interface, such as the first message. The processed data can be data obtained according to the to-be-processed data, such as the second message. The output circuit / interface is configured to output the processed data.

[0241] For example, the communication unit 2510 is configured to receive the first message sent by the terminal device. The description of the first message can be referred to the related description in the method embodiments as shown in the above. Figure 26 The communication apparatus 2600 provided by the embodiments of the present application is used for implementing the functions of the terminal device and the network device in the above method. The communication apparatus can be a terminal device, a network device, a chip for a terminal device or a network device, or an apparatus capable of matching the terminal device and the network device.

[0242] The communication apparatus 2600 comprises at least one processor 2620 configured to implement methods according to embodiments of the present application, for example, methods performed by a terminal device or a network device. The communication apparatus 2600 can also include a communication interface 2610. In embodiments of the present application, the communication interface can be a transceiver, a circuit, a bus, a module or another type of communication interface, configured to communicate with other devices through a transmission medium. For example, the communication interface 2610 is configured to enable the communication apparatus 2600 to communicate with other devices. When the communication apparatus 2600 is a terminal device, the processor 2620 can perform the functions of the processing unit 2320 as shown in Figure 23 , and the communication interface 2610 can perform the functions of the communication unit 2310 as shown in Figure 23 . When the communication apparatus 2600 is a network device, the processor 2620 can perform the functions of the processing unit 2520 as shown in Figure 25 , and the communication interface 2610 can perform the functions of the communication unit 2510 as shown in Figure 25 .

[0243] The communication apparatus 2600 can also include at least one memory 2630 configured to store program instructions and / or data. The memory 2630 is coupled to the processor 2620. The coupling between the memory 2630 and the processor 2620 is indirect coupling or communication connection between devices, units or modules, which can be electrical, mechanical or other forms, for information interaction between devices, units or modules. The processor 2620 can operate in cooperation with the memory 2630. The processor 2620 can execute program instructions stored in the memory 2630. At least one of the at least one memory can be included in the processor.

[0244] The specific connection medium between the communication interface 2610, the processor 2620 and the memory 2630 is not limited in embodiments of the present application. In embodiments of the present application, the memory 2630, the processor 2620 and the communication interface 2610 are connected through a bus 2640, and the bus is represented by a thick line in Figure 26 . The connection mode between other components is only schematically illustrated, and is not limited. The bus can be divided into an address bus, a data bus, a control bus, etc. For convenience, only one thick line is used to represent the bus in Figure 26 . Figure 26

[0245] As another form of the embodiment, a computer readable storage medium is provided, which stores instructions, and the instructions are executed to perform the method performed by the terminal device or the first network device or the second network device in the above method embodiment.

[0246] ​As another form of this embodiment, a computer program product containing instructions is provided, which, when executed, performs the method on the terminal device side, the first network device side, or the second network device side in the above method embodiment.

[0247] As another form of this embodiment, a communication system is provided. The system may include the at least one terminal device and the at least one network device mentioned above.

[0248] It should be understood that the processor mentioned in the embodiments of the present invention may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0249] It should also be understood that the memory referred to in the embodiments of the present application can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. Among them, the non-volatile memory can be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically EPROM (EEPROM) or a flash memory. The volatile memory can be a Random Access Memory (RAM) used as an external cache. By way of example but not limitation, many forms of RAM are available, such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM) and Direct Rambus RAM (DR RAM).

[0250] It should be noted that when the processor is a general processor, DSP, ASIC, FPGA or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, the memory (storage module) is integrated in the processor.

[0251] It should be noted that the memory described herein is intended to include, but not limited to, these and any other suitable types of memory.

[0252] It should be understood that in various embodiments of the present application, the size of the sequence number of the above-mentioned processes does not mean the order of execution, the execution order of the processes should be determined by its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0253] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software 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 beyond the scope of this application.

[0254] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0255] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0256] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0257] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0258] If the functions are implemented in the form of software function units and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the parts that contribute to the prior art or parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0259] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A communication method, characterized in that: include: The terminal device receives first configuration information; the first configuration information includes information of at least one candidate target primary and secondary cell and corresponding primary and secondary cell change execution condition information; The first configuration information is used to determine a first cell; the first cell is a cell that meets the primary and secondary cell change execution conditions among at least one candidate target primary and secondary cells; A radio link failure RLF occurs in the source primary cell group MCG or the source secondary cell group SCG of the terminal device, and the terminal device sends a first message; the first message includes first time period information; The first time period information includes at least one of the following: The time period information from when the terminal device receives the first configuration information to when the source MCG or the source SCG has an RLF; the time period information from when the source MCG or the source SCG has an RLF to when the terminal device sends the first message.

2. The method according to claim 1, characterized in that The terminal device sends a first message, including: When RLF occurs in the source MCG or source SCG and the first cell does not exist, the terminal device sends the first message.

3. The method according to claim 1, characterized in that The method further comprises: After an RLF occurs in the source SCG, the terminal device determines the first cell according to the first configuration information and initiates access to the first cell; If the terminal device successfully accesses the first cell, the first time period information further includes at least one of the following: Information about the time period between when the source SCG experiences RLF and when the terminal device determines the first cell; information about the time period between when the terminal device determines the first cell and when the terminal device successfully accesses the first cell; information about the time period between when the terminal device successfully accesses the first cell and when the terminal device sends the first message; If the terminal device fails to access the first cell and RLF does not occur in the source MCG, the first time period information further includes at least one of the following: Information about the time period between the occurrence of RLF in the source SCG and the determination of the first cell by the terminal device; information about the time period between the determination of the first cell by the terminal device and the failure of access of the terminal device to the first cell; information about the time period between the failure of access of the terminal device to the first cell and the sending of the first message by the terminal device; If the terminal device fails to access the first cell and RLF occurs in the source MCG, the first time period information includes at least one of the following: time period information from the start of RLF occurrence in the source SCG to the terminal device determining the first cell; time period information from the start of the terminal device determining the first cell to the start of RLF occurrence in the source MCG; time period information from the start of RLF occurrence in the source MCG to the terminal device failing to access the first cell; time period information from the start of the terminal device failing to access the first cell to the terminal device sending the first message; Alternatively, if the terminal device fails to access the first cell and RLF occurs in the source MCG, the first time period information further includes at least one of the following: The time period information from the time when the source SCG has an RLF to the time when the terminal device determines the first cell; the time period information from the time when the terminal device determines the first cell to the time when the terminal device fails to access the first cell; the time period information from the time when the terminal device fails to access the first cell to the time when the source MCG has an RLF; the time period information from the time when the source MCG has an RLF to the time when the terminal device sends the first message.

4. The method according to claim 1, wherein The method further comprises: Before the RLF occurs in the source MCG or source SCG, the terminal device determines the first cell, and the first time period information further includes at least one of the following: The time period information from when the terminal device receives the first configuration information to when the terminal device determines the first cell; the time period information from when the terminal device determines the first cell to when the source MCG or the source SCG experiences RLF.

5. The method according to claim 4, characterized in that The method comprises: The terminal device successfully accesses the first cell, and the first time period information further includes at least one of the following: The time period information between the occurrence of RLF in the source MCG or the source SCG and the terminal device accessing the first cell; the time end information between the start of the terminal device accessing the first cell and the terminal device sending the first message.

6. The method according to claim 4, characterized in that Before the RLF occurs in the source MCG, the terminal device determines the first cell, and the method further includes: The terminal device fails to access the first cell, and RLF does not occur in the source SCG. The first time period information further includes at least one of the following: Information about the time period between when the source MCG generates an RLF and when the terminal device fails to access the first cell; information about the time period between when the terminal device fails to access the first cell and when the terminal device sends the first message; or The terminal device fails to access the first cell, and RLF occurs in the source SCG, and the first time period information includes at least one of the following: time period information from the occurrence of RLF in the source MCG to the occurrence of RLF in the source SCG; time period information from the occurrence of RLF in the source SCG to the failure of the terminal device to access the first cell; time period information from the failure of the terminal device to access the first cell to the sending of the first message by the terminal device; Alternatively, the terminal device fails to access the first cell and RLF occurs in the source SCG, and the first time period information also includes at least one of the following: time period information from the occurrence of RLF in the source MCG to the failure of the terminal device to access the first cell; time period information from the failure of the terminal device to access the first cell to the occurrence of RLF in the source SCG; time period information from the occurrence of RLF in the source SCG to the terminal device sending the first message.

7. The method according to claim 4, characterized in that Before the RLF occurs in the source SCG, the terminal device determines the first cell, and the method further includes: The terminal device fails to access the first cell, and the source MCG does not have an RLF, and the first time period information further includes at least one of the following: time period information from the occurrence of the RLF in the source SCG to the failure of the terminal device to access the first cell; time period information from the failure of the terminal device to access the first cell to the sending of the first message by the terminal device; or The terminal device fails to access the first cell, and the source MCG has an RLF, and the first time period information further includes at least one of the following: time period information from the start of the RLF occurrence of the source SCG to the start of the RLF occurrence of the source MCG; time period information from the start of the RLF occurrence of the source MCG to the failure of the terminal device to access the first cell; time period information from the start of the failure of the terminal device to access the first cell to the sending of the first message by the terminal device; Alternatively, the terminal device fails to access the first cell and RLF occurs in the source MCG, and the first time period information also includes at least one of the following: time period information from the occurrence of RLF in the source SCG to the failure of the terminal device to access the first cell; time period information from the failure of the terminal device to access the first cell to the occurrence of RLF in the source MCG; time period information from the occurrence of RLF in the source MCG to the terminal device sending the first message.

8. The method according to claim 1, characterized in that After the terminal device successfully accesses the first cell, an RLF occurs in the source MCG or source SCG, and the first time period information further includes at least one of the following: Information about a time period between when the terminal device receives the first configuration information and when the terminal device determines the first cell; information about a time period between when the terminal device determines the first cell and when the terminal device successfully accesses the first cell; The time period information between the successful access of the terminal device to the first cell and the occurrence of RLF in the source MCG or source SCG.

9. The method according to any one of claims 1 to 8, characterized in that: The method further comprises: The terminal device sends a first indication message; the first indication message indicates that an RLF occurs in the source MCG or the source SCG.

10. The method according to any one of claims 1 to 8, characterized in that: The first message further includes at least one of the following: The cell information of the source main cell, the cell information of the source main and auxiliary cells, the cell information of the at least one candidate target main and auxiliary cell, the indication information that the terminal device has received the first configuration information, the indication information that the terminal device has determined the first cell or has not determined the first cell, and the indication information that the terminal device has successfully accessed the first cell or failed to access the first cell.

11. The method according to any one of claims 1 to 8, characterized in that: The method further comprises: The terminal device sends second indication information; The terminal device receives a request message in response to the second indication information; the request message requests the first message; The terminal device sending the first message includes: The terminal device sends the first message according to the request message.

12. A communication method, characterized in that: The method comprises: A first network device receives a first message sent by a terminal device; the first message includes first time period information of the terminal device; the first time period information includes at least one of the following: time period information from when the terminal device receives the first configuration information to when a radio link failure occurs in the source primary cell group MCG or the source secondary cell group SCG of the terminal device; time period information from when the source MCG or the source SCG occurs RLF to when the terminal device sends the first message; The first network device sends a second message to the second network device; the second message includes part or all of the first message; In which, the first network device is a network device that manages a source primary cell, and the second network device is a network device that manages a source primary and secondary cell; or, the first network device is a network device that manages a source primary and secondary cell, and the second network device is a network device that manages at least one candidate target primary and secondary cell; or, the first network device is a network device that manages a source primary and secondary cell, and the second network device is a network device that manages a source primary and secondary cell; or, the first network device is a network device that manages a source primary and secondary cell, and the second network device is a network device that manages at least one candidate target primary and secondary cell; or, the first network device is a network device that provides communication for the terminal device, and the second network device is a network device that manages a source primary and secondary cell; or, the first network device is a network device that provides communication for the terminal device, and the second network device is a network device that manages a source primary and secondary cell; or, the first network device is a network device that provides communication for the terminal device, and the second network device is a network device that manages at least one candidate target primary and secondary cell; the at least one candidate target primary and secondary cell is configured for the terminal device by the network device that manages the source primary cell of the terminal device.

13. The method according to claim 12, characterized in that The second message also includes first information, where the first information indicates that a too late condition occurs and the CPC of the primary and secondary cells is changed.

14. The method according to claim 12 or 13, characterized in that Also includes: The first network device determines, based on the first time period information, that an RLF occurs in the source SCG or the source MCG; The first network device releases the source SCG and / or the source MCG, or the first network device changes the SCG and / or MCG, or the first network device keeps the source SCG and / or the source MCG unchanged; wherein, the first network device is the network device that manages the source primary cell.

15. The method according to claim 12 or 13, characterized in that The first network device receiving a first message sent by a terminal device includes: The first network device receives second indication information sent by the terminal device; The first network device sends a request message to the terminal device in response to the second indication information; the request message requests the first message; The first network device receives the first message sent by the terminal device.

16. A communication method, characterized in that: include: The second network device receives the second message sent by the first network device; The second message includes first time period information of the terminal device; the first time period information includes at least one of the following: time period information from when the terminal device receives the first configuration information to when a radio link failure occurs in the source primary cell group MCG or the source secondary cell group SCG of the terminal device; time period information from when the source MCG or the source SCG occurs RLF to when the terminal device sends the first message, and the second message is determined based on the first message; The second network device sends a third message to the third network device; the third message includes part or all of the second message; Among them, the first network device is a network device that provides communication for the terminal device; the second network device is a network device that manages the at least one candidate target primary and secondary cells; and the third network device is a network device that manages the source primary cell or the source primary and secondary cells.

17. The method according to claim 16, characterized in that The third message includes first information indicating that too late CPC occurs.

18. A communication device, characterized in that: include: A processing unit, configured to receive first configuration information through a communication unit; the first configuration information includes information of at least one candidate target primary and secondary cell and corresponding primary and secondary cell change execution condition information; The first configuration information is used to determine a first cell; the first cell is a cell that meets the primary and secondary cell change execution conditions among at least one candidate target primary and secondary cells; A radio link failure RLF occurs in the source primary cell group MCG or the source secondary cell group SCG of the communication device, and the processing unit is further configured to send a first message through the communication unit; the first message includes first time period information; The first time period information includes at least one of the following: The time period information from when the communication device receives the first configuration information to when the source MCG or the source SCG has a radio link failure; the time period information from when the source MCG or the source SCG has an RLF to when the communication device sends the first message.

19. The communication device according to claim 18, wherein: When RLF occurs in the source MCG or source SCG and the first cell does not exist, the communication unit is used to send the first message.

20. The communication device according to claim 18, wherein: The processing unit is further configured to, after an RLF occurs in the source SCG, determine the first cell according to the first configuration information and initiate access to the first cell; If the first cell is successfully accessed, the first time period information further includes at least one of the following: Information about the time period between the occurrence of RLF in the source SCG and the determination of the first cell; information about the time period between the determination of the first cell by the communication device and the successful access of the communication device to the first cell; information about the time period between the successful access of the communication device to the first cell and the sending of the first message by the communication device; If access to the first cell fails and RLF does not occur in the source MCG, the first time period information further includes at least one of the following: Information about a time period between when the source SCG experiences an RLF and when the communication device determines the first cell; information about a time period between when the communication device determines the first cell and when the communication device fails to access the first cell; and information about a time period between when the communication device fails to access the first cell and when the communication device sends the first message. If the communication device fails to access the first cell and the source MCG has an RLF, the first time period information includes at least one of the following: time period information from when the source SCG has an RLF to when the communication device determines the first cell; time period information from when the communication device determines the first cell to when the source MCG has an RLF; time period information from when the source MCG has an RLF to when the communication device fails to access the first cell; time period information from when the communication device fails to access the first cell to when the communication device sends the first message; Alternatively, if the communication device fails to access the first cell and RLF occurs in the source MCG, the first time period information includes at least one of the following: The time period information from the time when the source SCG has an RLF to the time when the communication device determines the first cell; the time period information from the time when the communication device determines the first cell to the time when the communication device fails to access the first cell; the time period information from the time when the communication device fails to access the first cell to the time when the source MCG has an RLF; the time period information from the time when the source MCG has an RLF to the time when the communication device sends the first message.

21. The communication device according to claim 18, wherein Also includes: Before the RLF occurs in the source MCG or source SCG, the communication device determines the first cell, and the first time period information further includes at least one of the following: The time period information from when the communication device receives the first configuration information to when the communication device determines the first cell; the time period information from when the communication device determines the first cell to when the source MCG or the source SCG has an RLF.

22. The communication device according to claim 21, wherein: Also includes: The communication device successfully accesses the first cell, and the first time period information further includes at least one of the following: The time period information between the occurrence of RLF in the source MCG or the source SCG and the communication device accessing the first cell; the time period information between the access of the communication device to the first cell and the sending of the first message by the communication device.

23. The communication device according to claim 21, wherein: Before the RLF occurs in the source MCG, the communication device determines the first cell, further comprising: The communication device fails to access the first cell, and the source SCG does not experience RLF, and the first time period information further includes at least one of the following: Information about the time period between when the source MCG generates an RLF and when the communication device fails to access the first cell; information about the time period between when the communication device fails to access the first cell and when the communication device sends the first message; or The communication device fails to access the first cell, and RLF occurs in the source SCG, and the first time period information includes at least one of the following: time period information from when the source MCG experiences RLF to when the source SCG experiences RLF; time period information from when the source SCG experiences RLF to when the communication device fails to access the first cell; time period information from when the communication device fails to access the first cell to when the communication device sends the first message; Alternatively, the communication device fails to access the first cell and RLF occurs in the source SCG, and the first time period information also includes at least one of the following: time period information from the occurrence of RLF in the source MCG to the failure of the communication device to access the first cell; time period information from the failure of the communication device to access the first cell to the occurrence of RLF in the source SCG; time period information from the occurrence of RLF in the source SCG to the communication device sending the first message.

24. The communication device according to claim 21, wherein Before the RLF occurs in the source SCG, the communication device determines the first cell, further comprising: The communication device fails to access the first cell, and the source MCG does not have an RLF, and the first time period information further includes at least one of the following: time period information from the occurrence of the RLF in the source SCG to the failure of the communication device to access the first cell; time period information from the failure of the communication device to access the first cell to the communication device sending the first message; or The communication device fails to access the first cell, and the source MCG has an RLF, and the first time period information further includes at least one of the following: time period information from when the source SCG has an RLF to when the source MCG has an RLF; time period information from when the source MCG has an RLF to when the communication device fails to access the first cell; time period information from when the communication device fails to access the first cell to when the communication device sends the first message; Alternatively, the communication device fails to access the first cell and the source MCG has an RLF, and the first time period information also includes at least one of the following: time period information from the occurrence of RLF in the source SCG to the failure of the communication device to access the first cell; time period information from the failure of the communication device to access the first cell to the occurrence of RLF in the source MCG; time period information from the occurrence of RLF in the source MCG to the communication device sending the first message.

25. The communication device according to claim 18, wherein After the communication device successfully accesses the first cell, an RLF occurs in the source MCG or source SCG, and the first time period information further includes at least one of the following: The time period information from the time the communication device receives the first configuration information to the time the communication device determines the first cell; the time period information from the time the communication device determines the first cell to the time the communication device successfully accesses the first cell; the time period information from the time the communication device successfully accesses the first cell to the time the source MCG or source SCG experiences RLF.

26. The communication device according to any one of claims 18 to 25, characterized in that: The processing unit is further configured to: A first indication message is sent through the communication unit; the first indication message indicates that an RLF occurs in the source MCG or the source SCG.

27. The communication device according to any one of claims 18 to 25, characterized in that: The first message further includes at least one of the following: The cell information of the source primary cell, the cell information of the source primary and secondary cells, and the cell information of the at least one candidate target primary and secondary cell.

28. The communication device according to any one of claims 18 to 25, characterized in that: The processing unit is further configured to: sending second indication information through the communication unit; receiving, through the communication unit, a request message in response to the second indication information, wherein the request message is used to request the first message; When sending the first message through the communication unit, the processing unit sends the first message according to the request message.

29. A first communication device, characterized in that: The first communication device includes: A processing unit receives a first message sent by a terminal device through a communication unit; the first message includes first time period information of the terminal device; the first time period information includes at least one of the following: time period information from when the terminal device receives the first configuration information to when a radio link failure occurs in a source primary cell group MCG or a source secondary cell group SCG of the terminal device; time period information from when an RLF occurs in the source MCG or the source SCG to when the terminal device sends the first message; The processing unit is further configured to send a second message to a second communication device via the communication unit; the second message includes part or all of the first message; In which, the first communication device is a communication device for managing a source primary cell, and the second communication device is a communication device for managing a source primary and secondary cell; or, the first communication device is a communication device for managing a source primary and secondary cell, and the second communication device is a communication device for managing at least one candidate target primary and secondary cell; or, the first communication device is a communication device for managing a source primary and secondary cell, and the second communication device is a communication device for managing a source primary and secondary cell; or, the first communication device is a communication device for managing a source primary and secondary cell, and the second communication device is a communication device for managing at least one candidate target primary and secondary cell; or, the first communication device is a communication device for providing communication for the terminal device, and the second communication device is a communication device for managing a source primary and secondary cell; or, the first communication device is a communication device for providing communication for the terminal device, and the second communication device is a communication device for managing a source primary and secondary cell; or, the first communication device is a communication device for providing communication for the terminal device, and the second communication device is a communication device for managing at least one candidate target primary and secondary cell; the at least one candidate target primary and secondary cell is configured for the terminal device by the communication device that manages the source primary cell of the terminal device.

30. The first communication device according to claim 29, wherein: The second message also includes first information, where the first information indicates that a too late condition occurs and the CPC of the primary and secondary cells is changed.

31. The first communication device according to claim 29 or 30, characterized in that: The processing unit is also used to determine, based on the first time period information, that RLF occurs in the source SCG or source MCG; and release the source SCG and / or the source MCG, or the first communication device changes the SCG and / or MCG, or the first communication device keeps the source SCG and / or the source MCG unchanged; wherein the first communication device is the communication device that manages the source primary cell.

32. The first communication device according to claim 29 or 30, characterized in that: When the processing unit receives the first message sent by the terminal device through the communication unit, the processing unit is specifically configured to: receiving second indication information sent by the terminal device; In response to the second indication information, sending a request message to the terminal device; the request message is used to request the first message; Receive the first message sent by the terminal device.

33. A second communication device, characterized in that: include: Processing unit and communication unit The processing unit is configured to receive, through the communication unit, a second message sent by the first communication device; The second message includes first time period information of the terminal device; the first time period information includes at least one of the following: time period information from when the terminal device receives the first configuration information to when a radio link failure occurs in the source primary cell group MCG or the source secondary cell group SCG of the terminal device; time period information from when the source MCG or the source SCG occurs RLF to when the terminal device sends the first message, and the second message is determined based on the first message; The processing unit is further configured to send a third message to a third communication device via the communication unit; the third message includes part or all of the second message; Among them, the first communication device is a communication device that provides communication for the terminal equipment; the second communication device is a communication device that manages the at least one candidate target primary and secondary cells; and the third communication device is a communication device that manages the source primary cell or a communication device that manages the source primary and secondary cells.

34. The second communication device according to claim 33, characterized in that The third message includes first information indicating that too late CPC occurs.

35. A communication device, characterized in that: include: processor and memory, The memory is used to store computer programs or instructions; The processor is configured to execute a computer program or instruction in the memory, so that the method according to any one of claims 1 to 11 is executed, or the method according to any one of claims 12 to 15 is executed, or the method according to any one of claims 16 to 17 is executed.

36. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable instructions, which, when called by a computer, enable the computer to execute the method according to any one of claims 1 to 11, or the method according to any one of claims 12 to 15, or the method according to any one of claims 16 to 17.

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