A communication method and apparatus

Abstract

The application provides a communication method and device for realizing communication of a terminal device supporting multiple user identities. The method can be applied to a terminal device supporting a first communication system and a second communication system, the first communication system corresponding to a first user identity, and the second communication system corresponding to a second user identity. The method comprises: receiving, by the terminal device, a first message in the first communication system, the first message being used to indicate performing DAPS handover between a source cell and a target cell in the first communication system; and determining, by the terminal device, that a capability available for the first communication system cannot support the DAPS handover, then aborting communication with the source cell in the first communication system, and switching to the target cell in the first communication system, the capability of the terminal device being used for communication in the first communication system and the second communication system. By making the DAPS handover in the first communication system fall back to a basic handover, the terminal device can realize communication in multiple communication systems within the capability range.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a communication method and apparatus. Background Technology

[0002] When a terminal device registers with a network device, it reports its capabilities to the network device. The network device then determines how to configure and schedule the terminal device based on these capabilities. For terminal devices that support multiple user identities, such as dual-SIM terminal devices that support two Subscriber Identity modules (SIMs) within a single terminal device, the terminal device can communicate in two communication systems. These two communication systems can correspond to the first user identity and the second user identity, respectively. The terminal device's hardware resources are shared between the two user identities, and the terminal device's capabilities are used for communication between the two communication systems.

[0003] If a terminal device's communication activities in one communication system consume part of its capabilities, and if the terminal device receives a dual active protocol stack (DAPS) handover command in another communication system, the terminal device will maintain user plane connections with both the source and target cells during the DAPS handover process and continue data transmission with the source cell. However, the terminal device's communication activities in both communication systems may exceed its capabilities, resulting in communication failure. Therefore, how to enable communication for terminal devices that support multiple user identities has become a pressing technical problem that needs to be solved. Summary of the Invention

[0004] This application provides a communication method and apparatus for enabling terminal devices supporting multiple user identities to communicate.

[0005] Firstly, this application provides a communication method, the execution subject of which can be a terminal device, or a chip or circuit in the terminal device. The method includes: the terminal device receiving a first message in a first communication system, wherein the first message instructs the terminal device to perform a DAPS handover between a source cell and a target cell in the first communication system. The terminal device determines that the capabilities available to the first communication system cannot support DAPS handover, and the terminal device's capabilities are used for communication in a first communication system and a second communication system, where the first communication system corresponds to a first user identity and the second communication system corresponds to a second user identity. The terminal device then terminates communication with the source cell in the first communication system and hands over to the target cell in the first communication system.

[0006] In this embodiment of the application, when the DAPS handover of the terminal device in the first communication system and the communication behavior in other communication systems exceed the capabilities of the terminal device, by suspending communication with the source cell in the first communication system, the DAPS handover in the first communication system can be rolled back to a basic handover, thereby enabling the terminal device to switch to the target cell in the first communication system without affecting the communication of other communication systems. This approach avoids several issues. First, it prevents the terminal device from triggering an RRC reconfiguration due to the network configuration exceeding the terminal device's capabilities after receiving the RRC reconfiguration message for the DAPS handover command in the first communication system. This would interrupt the ongoing services in the first communication system and negatively impact the user experience of the terminal device as the first user. Second, it avoids the terminal device interrupting communication in other communication systems while performing a DAPS handover in the first communication system, thus affecting the user experience of the terminal device as the second user in the second communication system. Third, by falling back to basic handover, the terminal device can promptly switch to a target cell with better signal quality in the first communication system. This prevents the terminal device from spending too much time in the first communication system on a source cell with poor signal quality, which would negatively impact the communication quality of the first communication system. When the terminal device receives the RRC reconfiguration message for the DAPS handover command but cannot perform a DAPS handover, switching to a target cell with better signal quality according to the basic handover procedure can improve the communication performance in the first communication system.

[0007] In one possible design, the terminal device determines that the capabilities available for use in the first communication system cannot support DAPS handover, including: the terminal device determines that the carrier aggregation capabilities and / or dual connectivity capabilities available for use in the first communication system cannot support DAPS handover.

[0008] In one possible design, the first message carries configuration information for N radio bearers, and the configuration information for the N radio bearers carries DAPS configuration, where N is an integer greater than 0; the method also includes: not configuring the N radio bearers as DAPS bearers.

[0009] The above methods enable the terminal device to perform cell handover based on basic handover in the first communication system, thereby maintaining the terminal device's communication in the second communication system and the first communication system within the terminal device's capabilities, or ensuring that the resources used by the terminal device for communication in the first and second communication systems do not exceed the terminal device's hardware resources, thus avoiding communication interruptions.

[0010] In one possible design, the terminal device suspends communication with the source cell in the first communication system, including: the terminal device releasing the radio resource control (RRC) connection with the source cell; and / or, the terminal device suspending the transmission and reception of the data radio bearer (DRB) in the source primary cell group; and / or, the terminal device determining that the radio link of the source primary cell or the source primary cell group in the first communication system has failed. This design allows the terminal device to fall back to basic handover, thereby enabling it to hand over to the target cell within the first communication system within its capabilities.

[0011] In one possible design, the method further includes: if the terminal device successfully accesses the target cell, the terminal device sends first information to the target cell, wherein the first information indicates that the terminal device has terminated communication with the source cell due to resource conflict. This approach can help network devices optimize network mobility, such as optimizing the settings of mobility-related parameters, for example, the duration of timers related to the handover process, and the cell signal quality threshold during cell selection / reselection. Specific optimization parameters and parameter values ​​are not limited in this embodiment.

[0012] In one possible design, the method further includes: the terminal device sending indication information to the source cell in the first communication system, the indication information indicating that communication with the source cell has been suspended or is about to be suspended. This design, by indicating to the network device that communication with the source cell has been suspended or is about to be suspended, allows the network device to stop the source cell's scheduling of the terminal device, thereby avoiding resource waste.

[0013] Secondly, this application provides a communication method, the execution subject of which can be a network device, or a chip or circuit in the network device. The method includes: a first network device sending a first message to a terminal device, wherein the first message instructs the terminal device to perform a DAPS handover between a source cell and a target cell, the source cell belonging to the first network device; the first network device receiving first indication information from the terminal device, the first indication information indicating that communication with the source cell has been or will be terminated; and the first network device ceasing data scheduling for the terminal device in the source cell.

[0014] In this embodiment of the application, when the DAPS handover of the terminal device in the first communication system and the communication behavior in other communication systems exceed the capabilities of the terminal device, by suspending communication with the source cell in the first communication system, the DAPS handover in the first communication system can be rolled back to a basic handover, thereby enabling the terminal device to switch to the target cell in the first communication system without affecting the communication of other communication systems. This approach avoids several issues. First, it prevents the terminal device from triggering an RRC reconfiguration due to the network configuration exceeding the terminal device's capabilities after receiving the RRC reconfiguration message for the DAPS handover command in the first communication system. This would interrupt the ongoing services in the first communication system and negatively impact the user experience of the terminal device as the first user. Second, it avoids the terminal device interrupting communication in other communication systems while performing a DAPS handover in the first communication system, thus affecting the user experience of the terminal device as the second user in the second communication system. Third, by falling back to basic handover, the terminal device can promptly switch to a target cell with better signal quality in the first communication system. This prevents the terminal device from spending too much time in the first communication system on a source cell with poor signal quality, which would negatively impact the communication quality of the first communication system. When the terminal device receives the RRC reconfiguration message for the DAPS handover command but cannot perform a DAPS handover, switching to a target cell with better signal quality according to the basic handover procedure can improve the communication performance in the first communication system.

[0015] In one possible design, the first network device sends a second indication message to the second network device. This second indication message indicates that the terminal device has stopped or is about to stop communication with the source cell, and the target cell belongs to the second network device. This allows the target cell to determine that the terminal device has fallen back to basic handover in the first communication system, thereby preventing errors in communication between the target cell and the terminal device according to the DAPS handover mechanism.

[0016] In one possible design, the second indication information is sent to the second network device via a sequence number state transition message. This method implicitly indicates that communication with the source cell has been suspended or is about to be suspended, thus saving signaling overhead.

[0017] Thirdly, this application provides a communication method, the execution subject of which can be a terminal device, or a chip or circuit in the terminal device. The method includes: the terminal device determining that a first event has occurred; the terminal device sending indication information in a first communication system, the indication information being used to update the DAPS capability of the terminal device in the first communication system, wherein the indication information is effective for any combination of frequency bands of the terminal device, or the indication information is effective for a first frequency band in a first combination of frequency bands; the terminal device supports communication between the first communication system and a second communication system, the first communication system corresponding to a first user identity, and the second communication system corresponding to a second user identity.

[0018] In this embodiment, by instructing the terminal device to update its DAPS capabilities, the network device can instruct the terminal device to perform a handover based on the updated DAPS capabilities, thus avoiding the network device deciding to perform a DAPS handover for the terminal device that exceeds the terminal device's capabilities. Furthermore, in this embodiment, the instruction information can be specific to the terminal device, thereby saving signaling overhead. Alternatively, in this embodiment, the instruction information can also be specific to one or more frequency bands in a frequency band combination, thereby improving the flexibility of DAPS capability updates.

[0019] In one possible design, the indication information also indicates that intra-frequency DAPS handover is effective, and / or, inter-frequency DAPS handover is effective. This design allows for flexible updates to intra-frequency and inter-frequency DAPS handover.

[0020] In one possible design, the indication information indicates that the DAPS capability in the first communication system is suspended; the first event is entering RRC connection state in both the first and second communication systems; or, the first event is that the network protocol versions of the first and second communication systems are not lower than the 5G protocol version; or, the first event is that the RRC configuration in the first and second communication systems exceeds the baseband and / or radio frequency capabilities of the terminal device. Through this design, when the capabilities available to the terminal device in the first communication system are insufficient, the DAPS capability of the terminal device in the first communication system can be suspended, thereby enabling the terminal device to switch to the target cell and ensuring the communication quality of the terminal device in the first communication system.

[0021] In one possible design, the indication information indicates the restoration of DAPS capability in the first communication system; the first event is leaving the RRC connection state in the first and / or second communication system; or, the first event is that the network protocol version of the first and / or second communication system is lower than the 5G protocol version; or, the first event is that the capabilities available in the first communication system support DAPS handover between the source cell and the target cell in the first communication system. Through the above design, when the terminal device has sufficient capabilities available in the first communication system, the DAPS capability of the terminal device in the first communication system can be restored, thereby enabling the terminal device to perform DAPS handover in the first communication system, and thus reducing the communication latency of the terminal device in the first communication system.

[0022] Fourthly, this application provides a communication method, the execution subject of which can be a terminal device, or a chip or circuit in the terminal device. The method includes: the terminal device receiving a first message in a first communication system, wherein the first message instructs the terminal device to perform DAPS handover between a source cell and a target cell in the first communication system; the terminal device determining that the capabilities available to the first communication system cannot support DAPS handover, and the capabilities of the terminal device being used for communication in the first and second communication systems, the first communication system corresponding to a first user identity and the second communication system corresponding to a second user identity; the terminal device sending a request message in the second communication system, the request message requesting a scheduling interval, wherein the request message indicates at least one of the following: the purpose of requesting the scheduling interval, the frequency band identifier corresponding to the scheduling interval, the cell group identifier corresponding to the scheduling interval, and the cell identifier corresponding to the scheduling interval; after receiving a response message to the request message in the second communication system, the terminal device performs DAPS handover in the first communication system during the scheduling interval.

[0023] In this embodiment of the application, when the terminal device has resource conflicts with the DAPS handover in the first communication device and the services in the second communication system, it can request a scheduling interval from the network device of the second communication system to suspend the service transmission in the second communication system, thereby avoiding packet loss in the service transmission in the second communication system.

[0024] In one possible design, the method further includes: the terminal device determining that it has not received a response message within a first time period after sending the request message, or that the signal quality of the source cell in the first communication system is lower than a first threshold; the terminal device suspending communication with the source cell in the first communication system; and the terminal device switching to the target cell in the first communication system. This design avoids the terminal device switching to the target cell in the first communication system in a timely manner via basic handover before the signal quality of the source cell deteriorates, thus preventing communication interruption in the first communication system.

[0025] In one possible design, the method further includes: the terminal device sending indication information to the source cell in the first communication system, the indication information indicating that communication with the source cell has been suspended or is about to be suspended. This design, by indicating to the network device that communication with the source cell has been suspended or is about to be suspended, allows the network device to stop the source cell's scheduling of the terminal device, thereby avoiding resource waste.

[0026] In one possible design, the method further includes: the terminal device determining that it has not received a response message within a first time period after sending the request message, or that the signal quality of the source cell in the first communication system is lower than a first threshold; the terminal device performing a DAPS handover in the first communication system, and interrupting data transmission on a first resource in the second communication system during the DAPS handover, where data transmission on the first resource in the second communication system conflicts with the DAPS handover in the first communication system. This design avoids the terminal device from switching to the target cell in the first communication system before the signal quality of the source cell deteriorates, thus preventing communication interruption in the first communication system.

[0027] In one possible design, the request message is either a media access control (MAC) control element (CE) message or a physical layer message. This design can improve the scheduling interval for terminal device requests and the response speed of network devices, thereby enhancing communication performance.

[0028] In one possible design, there is a resource conflict between the DAPS handover in the first communication system and the services of the primary cell in the second communication system, and the cell identifier corresponding to the scheduling interval is the primary cell identifier in the second communication system.

[0029] And / or, there is a resource conflict between the DAPS handover in the first communication system and the services of the first secondary cell or the first secondary cell group in the second communication system, and the cell identifier corresponding to the scheduling interval is the first secondary cell identifier or the first secondary cell group identifier in the second communication system.

[0030] And / or, there is a resource conflict between the DAPS handover in the first communication system and the service in the second communication system on the first frequency band, and the frequency band identifier corresponding to the scheduling interval is the identifier of the first frequency band.

[0031] Through the above design, the second communication system can identify cells, frequency bands, etc. that have resource conflicts, and thus configure the scheduling interval of the cell.

[0032] In one possible design, the purpose of requesting a scheduling interval is to perform DAPS handover in the first communication system.

[0033] Fifthly, this application provides a communication method, the execution subject of which may be a terminal device, or a chip or circuit in the terminal device. The method includes: the terminal device receiving a first message in a first communication system, wherein the first message instructs the terminal device to perform a first DAPS handover between a first source cell and a first target cell in the first communication system, the first communication system corresponding to a first user identity; the terminal device receiving a second message in a second communication system, wherein the second message instructs the terminal device to perform a second DAPS handover between a second source cell and a second target cell in the second communication system, the second communication system corresponding to a second user identity; the terminal device performing the first DAPS handover in the first communication system and / or performing the second DAPS handover in the second communication system according to at least one of the following: the capabilities of the terminal device, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message.

[0034] In this embodiment, the handover priority of DAPS in two communication systems is determined, and the handover behavior in the two communication systems is determined according to the priority, thereby avoiding communication interruptions and packet loss in the two communication systems. This application prioritizes DAPS handover of the communication system with higher service priority and higher service latency requirements, which can improve user experience.

[0035] In one possible design, the terminal device performs a first DAPS handover in a first communication system and / or a second DAPS handover in a second communication system based on at least one of the following: the terminal device's capabilities, services in the first and second communication systems, or the reception time of a first message and the reception time of a second message, including: the terminal device determines that the priority of the first DAPS handover on the first communication system is higher than the priority of the second DAPS handover on the second communication system based on at least one of the following: the terminal device's capabilities, services in the first and second communication systems, or the reception time of the first and second messages. The terminal device performs the first DAPS handover in the first communication system. After performing the first DAPS handover, the terminal device performs the second DAPS handover in the second communication system.

[0036] The above design allows for DAPS handover to be performed in the higher-priority communication system when the terminal device's capabilities are insufficient to support DAPS handover between the two communication systems. Within the capabilities of the terminal device, it allows for handover to the target cell in both communication systems first, thereby reducing overall communication latency and improving user experience.

[0037] In one possible design, the terminal device performs a first DAPS handover in a first communication system and / or a second DAPS handover in a second communication system based on at least one of the following: the terminal device's capabilities, services in the first communication system and services in the second communication system, or the reception time of a first message and the reception time of a second message, including: the terminal device determining that the priority of the first DAPS handover on the first communication system is higher than the priority of the second DAPS handover on the second communication system based on at least one of the following: the terminal device's capabilities, services in the first communication system and services in the second communication system, or the reception time of a first message and the reception time of a second message; the terminal device performs a first DAPS handover in the first communication system; the terminal device suspends communication with a second source cell in the second communication system; and the terminal device switches to a second target cell in the second communication system.

[0038] The above design allows for DAPS handover to be performed in the higher-priority communication system and basic handover in the lower-priority communication system when the terminal device's capabilities are insufficient to support DAPS handover between the two communication systems. This approach prioritizes handover to the target cell in both communication systems within the terminal device's capabilities, thereby reducing overall communication latency and improving user experience.

[0039] In one possible design, the terminal device determines that the priority of a first DAPS handover on the first communication system is higher than the priority of a second DAPS handover on the second communication system based on at least one of the following: the hardware capabilities of the terminal device, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message, including: the terminal device determines that at least one of the following is satisfied: a preset relationship is satisfied based on the reception time of the first message and the reception time of the second message, the priority of the services in the first communication system is higher than the priority of the services in the second communication system, or the latency requirement of the services in the first communication system is higher than the latency requirement of the services in the second communication system; the terminal device determines that the priority of the first DAPS handover on the first communication system is higher than the priority of the second DAPS handover on the second communication system.

[0040] In one possible design, the preset relationship is: the first message is received earlier than the second message;

[0041] Alternatively, the second message may be received earlier than the first message.

[0042] Sixthly, this application also provides a communication device that has the function of implementing any of the methods provided in the first, third, fourth, or fifth aspects described above. This communication device can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more units or modules corresponding to the aforementioned functions.

[0043] In one possible design, the communication device includes a processor configured to support the communication device in performing corresponding functions of the network device described above. The communication device may also include a memory coupled to the processor, which stores necessary program instructions and data for the communication device. Optionally, the communication device further includes interface circuitry for supporting communication between the communication device and devices such as network devices.

[0044] For example, a communication device has the functionality to implement the method provided in the first aspect above, a transceiver for receiving a first message in a first communication system. A processor may be configured to: determine that the capabilities available to the first communication system cannot support DAPS handover, and terminate communication with the source cell in the first communication system, and handover to the target cell in the first communication system.

[0045] For example, the communication device has the functionality to implement the method provided in the third aspect above, and the processor can be used to: determine that a first event has occurred; and the transceiver is used to transmit indication information in the first communication system.

[0046] For example, a communication device may have the functionality to implement the method provided in the fourth aspect above, including a transceiver for receiving a first message in a first communication system; and a processor for determining that the capabilities available to the first communication system cannot support DAPS handover. The transceiver may also be used to send a request message in a second communication system; and the processor may further be used to perform DAPS handover in the first communication system during a scheduling interval after receiving a response message to the request message in the second communication system.

[0047] For example, a communication device may have the functionality to implement the method provided in the fifth aspect above, including a transceiver for receiving a first message in a first communication system and a second message in a second communication system. A processor may be configured to perform a first DAPS handover in the first communication system and / or a second DAPS handover in the second communication system based on at least one of the following: the capabilities of the terminal device, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message.

[0048] In one possible design, the communication device includes corresponding functional modules, each used to implement the steps in the above method. The functions can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the functions described above.

[0049] In one possible design, the communication device includes a processing unit (or processing module) and a communication unit (or communication module). These units can perform the corresponding functions in the above method examples, as described in the methods provided in the first, third, fourth, or fifth aspects, and will not be repeated here.

[0050] For example, a communication device has the functionality to implement the method provided in the first aspect above, a communication unit for receiving a first message in a first communication system, and a processing unit for: determining that the capabilities available to the first communication system cannot support DAPS handover, terminating communication with the source cell in the first communication system, and handing over to the target cell in the first communication system.

[0051] For example, the communication device has the function of implementing the method provided in the third aspect above, and the processing unit can be used to: determine that a first event has occurred; and the communication unit is used to send indication information in the first communication system.

[0052] For example, the communication device has the function of implementing the method provided in the fourth aspect above. A communication unit is used to receive a first message in a first communication system; a processing unit is used to determine that the capabilities available to the first communication system cannot support DAPS handover. The communication unit is also used to send a request message in a second communication system; the processing unit is further used to perform DAPS handover in the first communication system during a scheduling interval after receiving a response message to the request message in the second communication system.

[0053] For example, the communication device has the function of implementing the method provided in the fifth aspect above. The communication unit is configured to receive a first message in a first communication system and a second message in a second communication system. The processing unit can be configured to perform a first DAPS handover in the first communication system and / or a second DAPS handover in the second communication system according to at least one of the following: the capabilities of the terminal device, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message.

[0054] Seventhly, this application also provides a communication device that has the function of implementing any of the methods provided in the second aspect above. This communication device can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more units or modules corresponding to the above-described functions.

[0055] In one possible design, the communication device includes a processor configured to support the communication device in performing the corresponding functions of the network device described above. The communication device may also include a memory coupled to the processor, which stores necessary program instructions and data for the communication device. Optionally, the communication device further includes interface circuitry for supporting communication between the communication device and devices such as terminal devices.

[0056] For example, a communication device has the functionality to implement the method provided in the second aspect above, including a transceiver for sending a first message to a terminal device and receiving first indication information from the terminal device, and a processor for stopping data scheduling of the terminal device in the source cell.

[0057] In one possible design, the communication device includes a processing unit (or processing module) and a communication unit (or communication module). These units can perform the corresponding functions in the above method examples, as described in the methods provided in the first, third, fourth, or fifth aspects, and will not be repeated here.

[0058] For example, the communication device has the functionality to implement the method provided in the second aspect above, including a communication unit for sending a first message to a terminal device and receiving first indication information from the terminal device, and a processing unit for stopping data scheduling of the terminal device in the source cell.

[0059] Eighthly, a communication device is provided, including a processor and an interface circuit. The interface circuit is configured to receive signals from other communication devices outside the communication device and transmit them to the processor, or to send signals from the processor to other communication devices outside the communication device. The processor is configured to implement any of the methods provided in the first, third, fourth, or fifth aspects above through logic circuits or execution code instructions.

[0060] A ninth aspect provides a communication device including a processor and an interface circuit, the interface circuit being configured to receive signals from other communication devices outside the communication device and transmit them to the processor, or to send signals from the processor to other communication devices outside the communication device, the processor being configured to implement the methods of the second aspect and any possible design via logic circuits or execution code instructions.

[0061] In a tenth aspect, a computer-readable storage medium is provided that stores a computer program or instructions which, when executed by a processor, implement the methods of any one of the first to fifth aspects and any possible design described above.

[0062] In the eleventh aspect, a computer program product storing instructions is provided, which, when executed by a processor, implements any of the first to fifth aspects and any possible design methods described above.

[0063] In a twelfth aspect, a chip system is provided, comprising a processor and potentially a memory, for implementing the methods of any of the first to fifth aspects and any possible designs described above. The chip system may be composed of chips or may include chips and other discrete devices.

[0064] In a thirteenth aspect, a chip system is provided, comprising a processor and potentially a memory, for implementing the methods described in the second aspect and any possible designs. The chip system may be composed of chips or may include chips and other discrete devices.

[0065] In a fourteenth aspect, a communication system is provided, the system comprising the apparatus described in the first aspect and the apparatus described in the second aspect.

[0066] In a fifteenth aspect, a communication system is provided, the system comprising the apparatus described in the third aspect, and a network device, such as a terminal device, accessing a network device in the first communication system.

[0067] In a sixteenth aspect, a communication system is provided, the system comprising the apparatus described in the fourth aspect, a network device accessed by a terminal device in a first communication system, and a network device accessed by the terminal device in a second communication system.

[0068] In a seventeenth aspect, a communication system is provided, the system comprising the apparatus described in the fifth aspect, a network device accessed by a terminal device in a first communication system, and a network device accessed by the terminal device in a second communication system. Attached Figure Description

[0069] Figure 1 This is a schematic diagram of a basic switching process according to an embodiment of this application;

[0070] Figure 2 This is a schematic diagram of the architecture of a communication system according to an embodiment of this application;

[0071] Figure 3 This is a schematic diagram of the architecture of a communication system according to an embodiment of this application;

[0072] Figure 4 This is a flowchart illustrating a communication method according to an embodiment of this application;

[0073] Figure 5 This is a flowchart illustrating a switching process according to an embodiment of this application;

[0074] Figure 6 This is a flowchart illustrating a communication method according to an embodiment of this application;

[0075] Figure 7 This is a flowchart illustrating a communication method according to an embodiment of this application;

[0076] Figure 8 This is a flowchart illustrating a switching process according to an embodiment of this application;

[0077] Figure 9 This is a flowchart illustrating a communication method according to an embodiment of this application;

[0078] Figure 10 This is a flowchart illustrating a switching process according to an embodiment of this application;

[0079] Figure 11 This is a schematic diagram of the structure of a communication device according to an embodiment of this application;

[0080] Figure 12 This is a schematic diagram of the structure of a communication device according to an embodiment of this application. Detailed Implementation

[0081] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the embodiments of this application will be further described in detail below with reference to the accompanying drawings.

[0082] The following explanations of some terms used in the embodiments of this application are provided to facilitate understanding by those skilled in the art.

[0083] 1) The terminal device can be a device with wireless transceiver capabilities or a chip that can be installed in any device. It can also be referred to as user equipment (UE), access terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, wireless communication device, user agent, or user device. In the embodiments of this application, the terminal device can be a mobile phone, tablet computer, computer with wireless transceiver capabilities, X-reality (XR) devices (such as virtual reality (VR) devices, augmented reality (AR) devices, mixed reality (MR) technology, etc.), wireless terminals in industrial control, wireless terminals in self-driving cars, wireless terminals in video surveillance, and wearable terminal devices, etc. The terminal device can also be an enhanced mobile broadband (eMBB) UE, an ultra-reliable and low latency communication (URLLC) UE, a drone, other Internet of Things (IoT) devices, positioning devices, etc.

[0084] A network device can be any apparatus used to implement the functions of a network device. A network device can refer to a device in an access network that communicates with terminal devices over an air interface via one or more cells. Examples include a next-generation node B (gNB) in a new radio (NR) system and an evolved node B (eNB) in a long-term evolution (LTE) system. A network device can also be any apparatus that enables the network device to perform its functions, such as a chip system, which can be installed within the network device.

[0085] 2) Cell handover

[0086] In a communication system, when a terminal device in RRC connected state moves between cells, a cell handover procedure needs to be performed to change the serving cell of the terminal device in order to ensure that the terminal device can enjoy continuous network services within the network coverage area.

[0087] The handover process between cells for terminal devices is controlled by network equipment. The cell that provides services to the terminal device before the handover can be called the source cell, and the cell to which it is handover is called the target cell. The target cell provides services to the terminal device after a successful handover. Communication between the source cell and the target cell can be provided by different base stations. The base station providing communication to the source cell is called the source network equipment, and the base station providing communication to the target cell is called the target network equipment. When a terminal device hands over between base stations, explicit RRC signaling is required to trigger the cell handover.

[0088] When the source network device decides to trigger a handover based on the handover policy and the cell quality measurement results reported by the terminal device, it initiates a handover request to the target network device. The target network device performs admission control and responds to the source cell's handover request acknowledgement, providing a new RRC configuration carried in the handover command message. The source network device triggers the handover by sending an RRC reconfiguration message in the handover command, forwarding the RRC configuration provided by the target network device to the terminal device. The terminal device initiates a handover to the target cell based on the configuration information in the RRC reconfiguration message. This configuration information may include the target cell's physical cell identifier, a new cell radio network temporary identifier (C-RNTI), etc. The terminal device completes the synchronization process on the target cell based on the above configuration information. After a successful handover, the terminal device sends an RRC reconfiguration completion message to the target network device. For example, the cell handover process can be as follows: Figure 1 As shown. To distinguish it from the DAPS switching discussed below, the following will... Figure 1 The cell handover shown is called basic handover.

[0089] exist Figure 1 In the cell handover process shown, when the terminal device receives the RRC reconfiguration message from the source cell, it detaches the connection to the source cell and stops uplink and downlink data transmission with the source cell. The target network device only sends data to the terminal device after sending the RRC Reconfiguration Complete message indicating handover completion. During this handover process, before the terminal device establishes a connection with the target cell, it cannot transmit data because it has disconnected from the source cell and has not established a connection with the target cell, resulting in a transmission interruption.

[0090] To avoid interruptions during handover, DAPS handover has been proposed. DAPS handover refers to a handover process in which the connection with the source network device is maintained after receiving the RRC message for handover, and the source cell is released only after the target network device successfully accesses the network.

[0091] Unlike basic handover, during DAPS handover, after receiving the RRC reconfiguration message from the source network device, the terminal device stops sending and receiving RRC control plane signaling from the source cell, attaches the sigaling radio bearer (SRB) of the source cell, maintains the user plane connection with the source cell, and continues data transmission with the source cell until the terminal device successfully accesses the target network device. In the downlink direction, after sending the handover command RRC reconfiguration message, the source network device continues to send downlink data to the terminal device. After receiving the handover success message from the target network device, the source network device stops scheduling downlink. The terminal device continues to receive downlink data from the source cell until it disconnects from the source cell. In the uplink direction, after sending the handover command RRC reconfiguration message, the source network device continues to send uplink data to the terminal device. After receiving the handover success message from the target network device, the source network device stops scheduling uplink. The terminal device continues to send uplink data from the source cell until it successfully accesses the target cell.

[0092] 3) Same-frequency DAPS switching and different-frequency DAPS switching

[0093] If the center frequency of the source cell's synchronization signal / physical broadcast channel block (SSB) is the same as the center frequency of the target cell's SSB, and the subcarrier spacing of the two SSBs is also the same, then the DAPS handover is an intra-frequency DAPS handover. Otherwise, it is an inter-frequency DAPS handover.

[0094] 4) Multi-user identity terminal equipment

[0095] A terminal device can have multiple user identities. For example, a terminal device can have two user identities (such as a first user identity and a second user identity). The terminal device operates in the first communication system as the first user identity and in the second communication system as the second user identity.

[0096] In this application, "user identity" (e.g., first user identity, second user identity) is a logical concept. "User identity" can correspond to a Subscriber Identity Module (SIM) card, subscribed user information, a virtual SIM card, or a user identifier (such as an International Mobile Subscriber Identity (IMSI) / Temporary Mobile Subscriber Identity (TMSI)), and is not limited to natural person users or physical terminals (mobile phones). User identities may or may not be registered on the network, or it can be understood that the network may not be aware of the user identity of the terminal device (for example, a terminal device can receive broadcast data from network devices under a certain user identity). From the network's perspective, different "user identities" logically correspond to different communication entities served by the network. For example, a terminal with dual SIM cards represents two communication entities from the network's perspective. For example, when a "user" corresponds to a SIM card or subscribed user information, the network side will identify two terminals with different SIM cards or different subscribed user information as two different communication entities. It will also identify the same terminal device with multiple different SIM cards or multiple subscribed user information as multiple different communication entities, even though in reality, a terminal with multiple different SIM cards or multiple subscribed user information is only one physical entity. Communication systems corresponding to different user identities can belong to the same public land mobile network (PLMN) or different PLMNs. Furthermore, communication systems corresponding to different user identities can belong to the same operator network or different operator networks.

[0097] In the embodiments of this application, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0098] Furthermore, unless otherwise stated, the ordinal numbers such as "first" and "second" mentioned in the embodiments of this application are used to distinguish multiple objects and are not used to limit the size, content, order, timing, priority, or importance of the multiple objects. For example, "first communication system" and "second communication system" are only used to distinguish different communication systems and do not indicate that the two communication systems are different in terms of position, priority, or importance.

[0099] The preceding text introduced some terms and concepts involved in the embodiments of this application. The following text introduces the technical features involved in the embodiments of this application.

[0100] For terminal devices with multiple user identities, such as dual-SIM terminal devices, one terminal device supports two communication systems, which can correspond to the first user identity and the second user identity, respectively. When the terminal device registers with a communication system, it reports its capabilities to the network device corresponding to that communication system. The network device then determines how to configure and schedule the terminal device based on its capabilities. Therefore, for dual-SIM terminal devices, the terminal device can report its capabilities to the network device corresponding to each communication system when registering with both systems.

[0101] The communication behavior of terminal devices in different communication systems is independent of each other. From the perspective of network devices, they cannot perceive the communication behavior of terminal devices in multiple communication systems. From the perspective of the terminal device, the communication behavior of the terminal device in multiple communication systems shares the terminal device's capabilities (such as baseband processing capabilities, radio frequency capabilities, etc.). Therefore, for terminal devices with multiple user identities, if the network device corresponding to each communication system schedules the terminal device according to its maximum capacity, it will cause the terminal device to be unable to execute communication behavior in multiple communication systems simultaneously. This will result in the interruption of the terminal device's communication behavior in one or more communication systems, affecting the user experience.

[0102] Similarly, if a terminal device communicates on a first communication system as a first user (e.g., registered on the network with a first SIM card) and receives broadcast data on a second communication system as a second user (the second user is not registered on the network), when the communication activity on the second communication system consumes part of the terminal device's capacity, the terminal device cannot operate at its maximum capacity on the first communication system. If the network device corresponding to the first communication system schedules the terminal device according to its maximum capacity, it will affect normal communication behavior and impact user experience.

[0103] For example, if a terminal device's communication behavior in one communication system (let's say communication system 1) consumes part of its capacity, and the terminal device receives a handover command in another communication system (let's say communication system 2) instructing it to perform a DAPS handover, the terminal device will maintain the user plane connection of the source cell in communication system 2 and continue to transmit data with the source cell during the DAPS handover execution. However, at this time, the terminal device's communication behavior in the two communication systems may exceed its capacity, resulting in the inability to communicate normally.

[0104] Based on this, embodiments of this application provide a communication method and apparatus for enabling terminal devices supporting multiple user identities to communicate. The method and apparatus are based on the same concept; since the principles by which the method and apparatus solve problems are similar, the implementations of the apparatus and method can be mutually referenced, and repeated details will not be elaborated further.

[0105] The communication method provided in this application can be applied to various communication systems, such as the Internet of Things (IoT), narrowband Internet of Things (NB-IoT), LTE, fifth-generation (5G) communication systems, LTE and 5G hybrid architectures, 5G NR systems, 6G, or new communication systems that will emerge in the future development of communication.

[0106] The communication method provided in this application can be applied to a system including terminal devices and network devices. The terminal device can be a multi-user terminal device, such as a multi-SIM terminal device. The system may also include core network devices. Any two network devices in the communication system can connect to the same core network device or to different core network devices.

[0107] This communication system can be a 5G NR communication system. The interface between core network equipment and network equipment is an NG interface, and different network devices are connected via Xn interfaces. Taking a gNB or ng-eNB as the network equipment and an access and mobility management function (AMF) / user plane function (UPF) as the core network equipment as an example, the connection relationships between the AMF / UPF and network equipment, and between different AMF / UPF and network equipment, can be as follows: Figure 2 As shown.

[0108] This communication system can be an LTE communication system. The interface between the core network equipment and the network equipment is the S1 interface, and different network devices are connected via the X2 interface. Taking an eNB or en-gNB as the network equipment and an MME / S-GW as the core network equipment as an example, the connection relationships between the Mobility Management Entity (MME) and / or Serving Gateway (S-GW) and the network equipment, as well as between different MMEs / S-GWs and the network equipment, can be as follows: Figure 3 As shown.

[0109] The network architecture and business scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. As those skilled in the art will know, with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0110] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0111] The terminal device involved in this application can support a first user identity and a second user identity, wherein the first user identity corresponds to a first communication system and the second user identity corresponds to a second communication system. The first communication system may or may not be aware of the first user identity of the terminal device, and the second communication system may or may not be aware of the second user identity of the terminal device; this application does not impose specific limitations.

[0112] It should be noted that when a terminal device receives information / messages / data in the first communication system, it can also be described as the terminal device receiving information / messages / data as a first user. Similarly, when a terminal device receives information / messages / data in the second communication system, it can also be described as the terminal device receiving information / messages / data as a second user. In other words, actions performed by the terminal device as a first user can also be understood as actions performed in the first communication system. For the sake of brevity, this will not be repeated hereafter.

[0113] The first communication system can be a 5G network, or a 4G / 3G / 2G network, or any other network that emerges in the future development of communication. The second communication system can also be a 5G network, or a 4G / 3G / 2G network, or any other network that emerges in the future development of communication. The network protocol versions of the first and second communication systems can be the same or different.

[0114] The first communication system and the second communication system can belong to the same PLMN or to different PLMNs.

[0115] The first and second communication systems can belong to the same operator network or different operator networks.

[0116] It should be understood that the embodiments in this application are only illustrated by the example of a terminal device supporting two user identities, and do not limit the number of user identities supported by the terminal device.

[0117] See Figure 4 This is a flowchart illustrating a communication method provided in this application. The method includes:

[0118] S401, the first network device sends a first message to the terminal device. Correspondingly, the terminal device receives the first message from the first network device. Specifically, the terminal device may receive the first message as a first user.

[0119] The first message instructs the terminal device to perform a DAPS handover between the source cell and the target cell in the first communication system. The first message may also include the RRC configuration of the target cell. The first network device is the network device accessed by the terminal device in the first communication system; alternatively, it can be understood as the network device corresponding to the source cell where the terminal device performs the handover in the first communication system, or as the network device accessed by the terminal device as a first user. The target cell for the handover performed by the terminal device in the first communication system may correspond to a second network device. The first network device may be different from the second network device, for example, in a handover between base stations. The first network device may be the same as the second network device, for example, in a handover between different cells of the same base station.

[0120] For example, the first message could be an RRC reconfiguration message.

[0121] S402, The terminal device determines that the capabilities available for the first communication system cannot support DAPS handover.

[0122] The terminal device's capabilities are used to communicate in the first and second communication systems. In other words, the terminal device's capabilities are shared in communication between the two user identities. Therefore, the terminal device needs to determine whether it can perform DAPS handover as the first user identity while communicating as the second user identity.

[0123] As an example, the capability available for the first communication system cannot support DAPS handover, which can be understood as: the terminal device cannot simultaneously receive downlink and / or uplink data from the source cell and the target cell in the first communication system.

[0124] As another example, the capability available to the first communication system cannot support DAPS handover, which can be understood as: the network configuration / scheduling received by the terminal device on the first and second communication systems exceeds the maximum wireless access capability of the terminal device.

[0125] For example, the capabilities of a terminal device can be understood as its wireless access capabilities. For example, the capabilities of a terminal device can also be understood as its baseband processing capabilities and / or radio frequency capabilities, or its baseband processing resources and / or radio frequency resources. The baseband processing capabilities and / or radio frequency capabilities of the terminal device include at least one of the following: carrier aggregation capability supported by the terminal device, dual connectivity capability supported by the terminal device, frequency band combinations supported by the terminal device, frequency band combinations supported by the terminal device for carrier aggregation or dual connectivity, frequency bands supported by the terminal device, number of component carriers supported by the terminal device, processing capability of the terminal device for channel state information reference signal (CSI), multiple-input multiple-output (MIMO) capability of the terminal device, number of radio frequency channels supported by the terminal device, number of transmit / receive radio frequency links supported by the terminal device, and number of transmit / receive antennas supported by the terminal device.

[0126] Taking the terminal device's capability in terms of component carrier count as an example, one possible scenario is that the terminal device supports communication on 3 component carriers (this can be understood as the terminal device supporting carrier aggregation on 3 component carriers configured by the network device, or the terminal device supporting sending and receiving data on 3 component carriers). However, the terminal device requires the capability of 2 component carriers for DAPS handover. When the terminal device operates only in the first communication system, its capability can support communication on 3 component carriers, thus enabling DAPS handover. When the terminal device uses 2 component carriers for communication in the second communication system (this can be understood as the network device in the second communication system configuring or activating 2 component carriers for the terminal device), the capability available to the terminal device in the first communication system only supports communication on 1 component carrier. Therefore, the capability available to the terminal device in the first communication system cannot support DAPS handover in the first communication system.

[0127] Taking the capability of a terminal device as an example of frequency band combination, one possible scenario is that the terminal device's capability supports DAPS handover on two carriers with frequency band combination A and frequency band B. When the terminal device only operates in the first communication system, its capability can support DAPS handover on two carriers with frequency band combination A and frequency band B. However, when the terminal device communicates on frequency band C of the second communication system, its capability in the first communication system cannot support simultaneous reception and / or transmission of data on two carriers with frequency band combination A and frequency band B. If the network device of the first communication system instructs the terminal device to perform DAPS handover from the source cell on frequency band A (or frequency band B) to the target cell on frequency band B (or frequency band A), then the terminal device's capability cannot support performing DAPS handover between the source cell and the target cell with frequency band combination A and frequency band B.

[0128] Alternatively, the capabilities of a terminal device can also be understood as its carrier aggregation capability and / or dual connectivity capability.

[0129] In one specific implementation, the terminal device may determine that the carrier aggregation capability and / or dual connectivity capability available in the first communication system cannot support DAPS handover. For example, taking carrier aggregation capability as an example, one possible scenario is that the terminal device's communication in the second communication system occupies a portion of the terminal device's carrier aggregation capability, and the remaining carrier aggregation capability of the terminal device cannot support the terminal device to perform DAPS handover in the first communication system.

[0130] The embodiments of this application do not limit the state or behavior of the terminal device in the second communication system. The terminal device may be in an idle state or an inactive state, or it may be in an RRC connected state in the second communication system.

[0131] In one exemplary description, the communication behavior of the terminal device in the second communication system may include at least one of the following: receiving a paging, receiving a system message, performing a measurement of the serving cell or a neighboring cell, receiving or sending uplink service data, or receiving or sending downlink service data, receiving broadcast downlink service data, receiving multicast downlink service data or sending multicast uplink service data, and receiving or sending small data packets.

[0132] In one possible scenario, the DAPS handover of the terminal device in the first communication network and its communication behavior in the second communication network cannot coexist. For example, assuming the terminal device can operate on a single carrier in the second communication system, the incompatibility of the DAPS handover in the first communication network and its communication behavior in the second communication network can be understood as follows: the DAPS handover of the terminal device in the first communication network cannot coexist with communication in the primary cell (PCell) of the second communication network; or it can be understood as the terminal device being unable to receive and / or transmit data in the source cell and target cell of the first communication system while simultaneously communicating in the primary cell of the second communication system.

[0133] For example, suppose that the terminal device can operate in the second communication system in the form of carrier aggregation (CA) or dual-connectivity (DC). The DAPS handover of the terminal device in the first communication network and the communication behavior in the second communication network cannot coexist. This can be understood as: the DAPS handover of the terminal device in the first communication network may not be able to coexist with one or more secondary cells (SCell) or secondary cell groups (SCG) in the second communication system.

[0134] S403, the terminal device terminates communication with the source cell in the first communication system.

[0135] For example, the terminal device suspends communication with the source cell in the first communication system, which can be achieved through at least one of the following six methods:

[0136] Method 1: The terminal device releases the RRC connection with the source cell of the first communication system.

[0137] Method 2: The terminal device suspends the transmission and reception of the DRB of the source main cell group of the first communication system.

[0138] Method 3: The terminal device determines that the wireless link of the source cell or source cell group of the first communication system has failed.

[0139] During the handover process, the terminal device switches to the primary cell it was previously connected to; in other words, the source cell during the handover is the primary cell the terminal device was connected to before the handover. Therefore, the source cell of the first communication system mentioned above can also be called the source primary cell of the first communication system. Thus, in this application, the source primary cell of the first communication system and the source cell in the first communication system mentioned above can be understood to have the same meaning. The source primary cell group in the first communication system may include the source cells in the first communication system mentioned above.

[0140] Method 4: The terminal device is detached from the source cell in the first communication system.

[0141] Method 5: The terminal device stops downlink and / or uplink communication with the source cell in the first communication system.

[0142] Method 6: The terminal device releases the resources and configurations of the source cell in the first communication system, specifically including at least one of the following: radio resource configuration, access layer security configuration, measurement configuration, physical channel configuration, MAC configuration, radio link control (RLC) configuration / RLC entity, and PDCP configuration / PDCP entity.

[0143] Optionally, the terminal device may also send a first indication message to the first network device, the first indication message indicating that communication with the source cell has been suspended or is about to be suspended. Alternatively, the first indication message indicates that downlink and / or uplink communication with the source cell has been stopped or is about to be stopped. Alternatively, the first indication message indicates that the RRC connection with the source cell has been released or is about to be released. Alternatively, the first indication message indicates that DAPS handover of the terminal device in the first communication system has been suspended or is about to be suspended. Alternatively, the first indication message indicates that the transmission and reception of DRB in the source primary cell group has been suspended or is about to be suspended. Alternatively, the first indication message indicates that a DAPS handover has been or is about to be rolled back to a basic handover.

[0144] Accordingly, after receiving the first instruction information, the first network device may stop data scheduling for the terminal device on the source cell, or it may be described as stopping communication with the terminal device on the source cell.

[0145] In one possible embodiment, the first network device may further send a second indication message to the second network device. The second indication message indicates that data scheduling with the source cell has been or will be suspended, or that a handover from DAPS to basic handover has been or will be rolled back, or that an RRC connection with the source cell has been or will be released. In one implementation, the first network device may implicitly indicate the second indication message via a Sequence Number State Transition (SN STATUS TRANSFER) message. In another implementation, the first network device may also explicitly send the second indication message.

[0146] Optionally, if the first network device explicitly sends the second indication information to the second network device, after the terminal device successfully accesses the target cell and sends an RRC reconfiguration completion message to the target cell, the second network device may not need to send a handover success message to the first network device.

[0147] Alternatively, if the second network device receives the SN STATUS TRANSFER message from the first network device before receiving the RRC reconfiguration complete message from the terminal device, and this message implicitly indicates the second indication information, then the second network device does not need to send a handover success message to the first network device after receiving the RRC reconfiguration complete message from the terminal device.

[0148] The second network device is the network device that the terminal device will switch to in the first communication system, or it can be understood as the network device corresponding to the target cell of the terminal device in the first communication system.

[0149] For example, the first network device is the source network device in which the terminal device performs a handover in the first communication system, and the second network device is the target network device in which the terminal device performs a handover in the first communication system.

[0150] It should be noted that the above embodiments are illustrated by the fact that the source cell and target cell of the terminal device in the first communication system correspond to different network devices. In specific implementations, the source cell and target cell of the terminal device in the first communication system may also correspond to the same network device, which is not specifically limited here.

[0151] S404, the terminal device switches to the target cell in the first communication system.

[0152] In this embodiment of the application, when the DAPS handover of the terminal device in the first communication system and the communication behavior in other communication systems exceed the capabilities of the terminal device, by suspending communication with the source cell in the first communication system, the DAPS handover in the first communication system can be rolled back to a basic handover, thereby enabling the terminal device to switch to the target cell in the first communication system without affecting the communication of other communication systems. This approach avoids several issues. First, it prevents the terminal device from triggering an RRC reconfiguration due to the network configuration exceeding the terminal device's capabilities after receiving the RRC reconfiguration message for the DAPS handover command in the first communication system. This would interrupt the ongoing services in the first communication system and negatively impact the user experience of the terminal device as the first user. Second, it avoids the terminal device interrupting communication in other communication systems while performing a DAPS handover in the first communication system, thus affecting the user experience of the terminal device as the second user in the second communication system. Third, by falling back to basic handover, the terminal device can promptly switch to a target cell with better signal quality in the first communication system. This prevents the terminal device from spending too much time in the first communication system on a source cell with poor signal quality, which would negatively impact the communication quality of the first communication system. When the terminal device receives the RRC reconfiguration message for the DAPS handover command but cannot perform a DAPS handover, switching to a target cell with better signal quality according to the basic handover procedure can improve the communication performance in the first communication system.

[0153] In one possible implementation, the first message may also carry configuration information for N radio bearers, where N is an integer greater than 0, carrying DAPS configuration. "Carrying DAPS configuration" can be understood as setting the DAPS configuration information element (DAPS-Config) to true. After determining that the capabilities available to the first communication system cannot support DAPS handover, the terminal device may not configure the N radio bearers as DAPS bearers. Alternatively, "not configuring the N radio bearers as DAPS bearers" can also be described as "configuring the N radio bearers as non-DAPS bearers," or "ignoring the DAPS configuration of the N radio bearers in the first message," or "treating the DAPS configuration of the N radio bearers as not configured (not true)." The aforementioned radio bearers can be data radio bearers (DRBs).

[0154] The above methods enable the terminal device to perform cell handover based on basic handover in the first communication system, thereby maintaining the terminal device's communication in the second communication system and the first communication system within the terminal device's capabilities, or ensuring that the resources used by the terminal device for communication in the first and second communication systems do not exceed the terminal device's hardware resources, thus avoiding communication interruptions.

[0155] Optionally, after configuring the N radio bearers as non-DAPS, if the terminal device experiences an RRC synchronization reconfiguration failure, the terminal device can trigger an RRC connection re-establishment.

[0156] Optionally, the first message may also carry configuration information for other radio bearers. For example, the first message may carry configuration information for M radio bearers, where the configuration information for these M radio bearers does not include DAPS configuration, and M is an integer greater than 0. The other radio bearers may be data radio bearers (DRBs).

[0157] In one embodiment, if the terminal device successfully accesses the target cell of the first communication system, the terminal device can also send first information to the network device corresponding to the target cell. The first information indicates that the terminal device has suspended communication with the source cell due to resource conflicts. "The terminal device suspends communication with the source cell due to resource conflicts" can also be understood as the terminal device suspending communication with the source cell due to insufficient capabilities available to the first communication system, temporary limitations on the capabilities available to the first communication system, insufficient hardware resources available to the terminal device, temporary limitations on the resources available to the terminal device, dual-SIM issues, capability sharing issues, or dual-SIM resource sharing issues. "Suspension of communication with the source cell" can be understood as suspending communication with the source cell during DAPS handover, releasing the RRC connection with the source cell during DAPS handover, falling back from DAPS handover to basic handover, or a radio link failure (RLF) occurring in the source cell during DAPS handover.

[0158] This approach can help network devices optimize network mobility, such as optimizing the settings of mobility-related parameters, such as the duration of timers related to the handover process and the cell signal quality threshold during cell selection / reselection. The specific optimization parameters and parameter values ​​are not limited in this embodiment.

[0159] In one specific implementation, if the terminal device successfully accesses the target cell of the first communication system, the terminal device can send a success handover report (SHR) to the target cell, wherein the success handover report may carry first information. For example, the success handover report may indicate the first information through a new SHR-cause value.

[0160] In one embodiment, if the terminal device fails to handover in the first communication system, such as due to RRC synchronization reconfiguration failure or timer T304 timeout, the terminal device records second information. This second information indicates that during DAPS handover, the terminal device suspended communication with the source cell due to resource conflicts. The suspension of communication with the source cell is understood as described above and will not be repeated here. After the terminal device re-establishes the RRC connection, it reports the second information to the successfully accessed serving cell. In one specific implementation, the second information is the variable RLF-report.

[0161] To better understand the solution provided in this application, the switching process is described below as an example.

[0162] like Figure 5 As shown, the switching process includes:

[0163] S501, the terminal device sends a measurement report to the first network device. The measurement report may carry measurement results for the serving cell and at least one neighboring cell.

[0164] S502, the first network device makes the handover decision.

[0165] S503, the first network device sends a handover request message to the second network device.

[0166] The handover request message is used to request that the terminal device be switched to the target cell of the second network device.

[0167] S504, the second network device performs access control.

[0168] S505, the second network device sends a handover request response message to the first network device.

[0169] The handover request response message is used to allow the terminal device to hand over to the target cell of the second network device. The handover request response message contains a handover command, which provides the first network device with the RRC configuration of the target cell.

[0170] S506, the first network device sends the first message to the terminal device.

[0171] For details regarding the first message, please refer to the relevant description in S401; it will not be repeated here.

[0172] Optionally, the first network device sends an early state transition message to the second network device.

[0173] The early state transition message is used to indicate the sequence number of the downlink data that the first network device has sent to the terminal device.

[0174] S507, The terminal device determines that the capabilities available for use in the first communication system cannot support DAPS handover.

[0175] For details on this step, please refer to the relevant description in S402; it will not be repeated here.

[0176] S508, the terminal device sends a first instruction message to the first network device.

[0177] The first instruction information can be described in detail in the previous text, and will not be repeated here.

[0178] S509, the first network device terminates communication with the source cell of the first network device.

[0179] It should be noted that this application does not limit the execution order of S509 and S510.

[0180] S510, the terminal device performs random access on the target cell of the second network device.

[0181] S511, the terminal device sends a handover completion message to the first network device.

[0182] In this embodiment of the application, when the DAPS handover of the terminal device in the first communication system and the communication behavior in other communication systems exceed the capabilities of the terminal device, by suspending communication with the source cell in the first communication system, the DAPS handover in the first communication system can be rolled back to a basic handover, thereby enabling the terminal device to switch to the target cell in the first communication system without affecting the communication of other communication systems. This approach avoids several issues. First, it prevents the terminal device from triggering an RRC reconfiguration due to the network configuration exceeding the terminal device's capabilities after receiving the RRC reconfiguration message for the DAPS handover command in the first communication system. This would interrupt the ongoing services in the first communication system and negatively impact the user experience of the terminal device as the first user. Second, it avoids the terminal device interrupting communication in other communication systems while performing a DAPS handover in the first communication system, thus affecting the user experience of the terminal device as the second user in the second communication system. Third, by falling back to basic handover, the terminal device can promptly switch to a target cell with better signal quality in the first communication system. This prevents the terminal device from spending too much time in the first communication system on a source cell with poor signal quality, which would negatively impact the communication quality of the first communication system. When the terminal device receives the RRC reconfiguration message for the DAPS handover command but cannot perform a DAPS handover, switching to a target cell with better signal quality according to the basic handover procedure can improve the communication performance in the first communication system.

[0183] Another communication method is provided below. This method, when a terminal device determines that the DAPS handover in the first communication system and the communication behavior in other communication systems have exceeded or are about to exceed the terminal device's capabilities, instructs the terminal device to suspend the DAPS capability in the first communication system. This allows the network device corresponding to the first communication system to instruct the terminal device to perform a basic handover in the first communication system, thus preventing the handover in the first communication system from exceeding the terminal device's capabilities. Alternatively, when it is determined that the DAPS handover in the first communication system and the communication behavior in other communication systems no longer exceed or are about to no longer exceed the terminal device's capabilities, the method instructs the terminal device to restore the DAPS capability in the first communication system. This allows the network device corresponding to the first communication system to instruct the terminal device to perform a DAPS handover in the first communication system, thereby reducing the communication latency when the terminal device performs a handover in the first communication system. This communication method is described in detail below.

[0184] See Figure 6 The diagram shown is a flowchart illustrating a communication method provided in this application. The method includes:

[0185] S601, the terminal device determines that the first event has occurred.

[0186] S602, the terminal device sends indication information in the first communication system. Correspondingly, the first network device receives the indication information from the terminal device. Specifically, the terminal device may send the indication information as a first user.

[0187] The first network device is the network device that the terminal device accesses in the first communication system.

[0188] The instruction information is used to update the DAPS capabilities of the terminal device in the first communication system.

[0189] The indication information can specify the update of DAPS capabilities for each UE. Therefore, the indication information applies to any combination of frequency bands or any carrier frequency band of the terminal device; that is, the indication information is applicable to the terminal device, and can also be understood as indicating the update of the DAPS capabilities of the terminal device (or all frequency band combinations of the terminal device) in the first communication system. Correspondingly, after receiving the indication information, the first network device updates the DAPS capabilities of all frequency band combinations of the terminal device according to the indication information. For example, the indication information can be 1 bit. In this embodiment, the indication information can be specific to the terminal device, thereby saving signaling overhead.

[0190] Alternatively, the indication information may also indicate the capability to update the per-band combination per-band. Therefore, the indication information applies to at least one band (e.g., the first band) in the first band combination, meaning it applies to at least one band in the first band combination of the terminal device. This can also be understood as indicating an update to the DAPS capability of the terminal device in at least one band of the first band combination in the first communication system. Correspondingly, after receiving the indication information, the first network device updates the DAPS capability of at least one band in the first band combination of the terminal device according to the indication information. In this embodiment, the indication information may also apply to one or more bands in the band combination, thereby improving the flexibility of DAPS capability updates.

[0191] In one specific example, the at least one frequency band of the first frequency band combination may include the frequency band in which the terminal device communicates with the source cell of the first communication system.

[0192] For example, if a terminal device communicates with the source cell of a first communication system in band A, the indication information can indicate the DAPS capability of band A+band B in the band combination band A+band B+band C. Correspondingly, upon receiving this indication information, the first network device can understand that the terminal device does not currently support DAPS handover between carrier pairs of band A+band B in the band combination band A+band B+band C of the first communication system.

[0193] Furthermore, this instruction information can also indicate the updating of the DAPS capability of the per-band combination. Therefore, the instruction information applies to the first band combination, meaning it is applicable to the first band combination of the terminal device. This can also be understood as the instruction information indicating the updating of the DAPS capability of the terminal device in the first communication system for the first band combination. In a specific example, the first band combination may include the frequency band in which the terminal device communicates with the source cell of the first communication system.

[0194] For example, if a terminal device communicates with the source cell of a first communication system in band A, the indication information can indicate the DAPS capability of the updated frequency band combination band A+bandB+bandC. Correspondingly, upon receiving this indication information, the first network device can understand that the terminal device does not support DAPS handover between carrier pairs in the band A+bandB+bandC frequency band combination of the first communication system.

[0195] Optionally, the indication information may also indicate whether the update is for intra-frequency DAPS switching capability and / or inter-frequency DAPS switching capability. Specifically, the indication information may explicitly indicate that intra-frequency DAPS switching and / or inter-frequency DAPS switching is effective, or it may implicitly indicate that intra-frequency DAPS switching and / or inter-frequency DAPS switching is effective.

[0196] When a terminal device registers with the network, it reports its DAPS handover capabilities in its UE capability information. In this embodiment, by instructing the terminal device to update its DAPS capabilities, the network device can instruct the terminal device to perform a handover based on the updated DAPS capabilities, avoiding situations where the network device decides to perform a DAPS handover beyond the terminal device's capabilities. Furthermore, in this embodiment, the instruction information can be specific to the terminal device, thereby saving signaling overhead. Alternatively, in this embodiment, the instruction information can also be specific to one or more frequency bands in a frequency band combination, thereby improving the flexibility of DAPS capability updates.

[0197] The following example illustrates the update behavior of the first event and the DAPS capability.

[0198] In one exemplary embodiment, the instruction information can indicate suspending the DAPS capability in the first communication system, or it can indicate restoring the DAPS capability in the first communication system. Suspending the DAPS capability in the first communication system can be understood as disabling the DAPS capability in the first communication system, or it can also be understood as temporarily restricting the DAPS capability in the first communication system, or it can also be understood as temporarily not supporting the DAPS capability in the first communication system. Correspondingly, restoring the DAPS capability in the first communication system can be understood as enabling the DAPS capability in the first communication system, or it can also be understood as removing the restriction on the DAPS capability in the first communication system, or it can also be understood as restoring the DAPS capability in the first communication system.

[0199] In one possible implementation, the indication information may indicate the DAPS capability of the suspended terminal device in the first communication system when the first event is any of the following:

[0200] The first event is that the terminal device enters the RRC connection state in both the first and second communication systems, or the first event is that the terminal device is in the service receiving or sending state in one of the first and second communication systems, and is about to start or has already started service receiving or sending in the other communication system.

[0201] Alternatively, the first event is that the version of the network protocol used by the terminal device to communicate between the first and second communication systems is not lower than the version of the 5G protocol. Taking 5G as an example, this event can also be described as the terminal device enabling 5G mode for communication in both the first and second communication systems, or the terminal device establishing a connection with the network device based on the 5G protocol in both the first and second communication systems, or the terminal device having both its first user identity and its second user identity enabled the 5G switch.

[0202] Alternatively, the first event is that the RRC configuration of the terminal device in the first communication system and the RRC configuration in the second communication system exceed the baseband and / or radio frequency capabilities of the terminal device. For example, the event may be that the number of carriers occupied by the terminal device for communication in the first and second communication systems has reached or is about to reach the maximum baseband processing capability of the terminal device. If a target cell for DAPS handover is added to the first or second communication system, the number of carriers occupied by the terminal device for communication in the first and second communication systems will exceed the maximum baseband processing capability of the terminal device.

[0203] In another possible implementation, the indication information may indicate the restoration of the DAPS capability of the terminal device in the first communication system when the first event is any of the following:

[0204] The first event is when the terminal device leaves the RRC connection state in the first and / or second communication system. Alternatively, it can be described as the terminal device entering an idle or inactive state in the first and / or second communication system. Alternatively, this event can also be understood as the terminal device being in a service receiving or transmitting state in one of the first and second communication systems, and about to stop or has already stopped receiving or transmitting services in the other communication system.

[0205] Alternatively, the first event is that the network protocol version used by the terminal device to communicate in the first and / or second communication systems is lower than the 5G protocol version. Taking 5G as an example, this event can also be described as the terminal device using 4G, 3G, or 2G for communication in at least one of the first and second communication systems; or, the terminal device establishing a connection with the network device based on 4G, 3G, or 2G protocols in at least one of the first and second communication systems; or, at least one of the first and second user identities of the terminal device turning off the 5G switch.

[0206] Alternatively, the first event is that the terminal device's capability in the first communication system supports DAPS handover between the source cell and the target cell in the first communication system. For example, this event could be that the number of carriers occupied by the terminal device for communication in the first and second communication systems does not exceed the terminal device's maximum baseband processing capability. If a target cell for DAPS handover is added to the first or second communication system, the number of carriers occupied by the terminal device for communication in the first and second communication systems will still not exceed the terminal device's maximum baseband processing capability.

[0207] In this embodiment, by instructing the terminal device to update its DAPS capabilities, the network device can instruct the terminal device to perform a handover based on the updated DAPS capabilities, thus avoiding the network device deciding to perform a DAPS handover for the terminal device that exceeds the terminal device's capabilities. Furthermore, in this embodiment, the instruction information can be specific to the terminal device, thereby saving signaling overhead. Alternatively, in this embodiment, the instruction information can also be specific to one or more frequency bands in a frequency band combination, thereby improving the flexibility of DAPS capability updates.

[0208] Another communication method is provided below. This method involves requesting a scheduling interval in the second communication system when the terminal device determines that the DAPS handover in the first communication system and the communication behavior in other communication systems have exceeded or are about to exceed the terminal device's capabilities. This allows the DAPS handover in the first communication system to be performed within the scheduling interval. This approach avoids packet loss during service transmission in the second communication system. The following is a detailed description of this communication method.

[0209] See Figure 7 The diagram shown is a flowchart illustrating a communication method provided in this application. The method includes:

[0210] S701, the first network device sends a first message to the terminal device. Correspondingly, the terminal device receives the first message from the first network device. Specifically, the terminal device can receive the first message as a first user.

[0211] For details on S701, please refer to the relevant description of S401; it will not be repeated here.

[0212] S702, The terminal device determines that the capabilities available for the first communication system cannot support DAPS handover.

[0213] For details on S702, please refer to the relevant description of S402; it will not be repeated here.

[0214] S703, the terminal device sends a request message in the second communication system. Correspondingly, the third network device receives the request message from the terminal device. Specifically, the terminal device can send the request message to the third network device as a second user.

[0215] The third network device is the network device through which the terminal device accesses the second communication system, or it can be understood as the network device through which the terminal device accesses the system as a second user. The third network device and the first network device can be the same network device or different network devices.

[0216] The request message is used to request a scheduling interval, or to request the activation of a configured scheduling interval. During the specified scheduling interval, the third network device stops scheduling data for the terminal device.

[0217] The request message indicates at least one of the following: the purpose of requesting a scheduling interval, the frequency band identifier corresponding to the scheduling interval, the cell group identifier corresponding to the scheduling interval, and the cell identifier corresponding to the scheduling interval. The purpose of requesting a scheduling interval can also be referred to as the reason for requesting a scheduling interval.

[0218] Optionally, the purpose of requesting a scheduling interval may be to perform a DAPS handover in the first communication system. In one implementation, the purpose of requesting a scheduling interval may be indicated by the cause value in the request message.

[0219] In one exemplary embodiment, the frequency band identifier corresponding to the scheduling interval can be the identifier of a frequency band that conflicts with the DAPS handover in the first communication system. For example, assuming that the DAPS handover in the first communication system conflicts with the service on the first frequency band in the second communication system, the frequency band identifier corresponding to the scheduling interval is the identifier of the first frequency band.

[0220] The cell group identifier corresponding to the scheduling interval can be the identifier of a cell group that has resource conflicts with the DAPS handover in the first communication system. For example, assuming that the DAPS handover in the first communication system has resource conflicts with the services of the first secondary cell or the first secondary cell group in the second communication system, the cell identifier corresponding to the scheduling interval is the identifier of the first secondary cell or the identifier of the first secondary cell group in the second communication system.

[0221] The cell identifier corresponding to the scheduling interval can be the identifier of a cell that has a resource conflict with the DAPS handover in the first communication system. For example, assuming that the DAPS handover in the first communication system has a resource conflict with the service of the primary cell in the second communication system, the cell identifier corresponding to the scheduling interval is the identifier of the primary cell in the second communication system.

[0222] In addition, the request message can also indicate information such as the start time of the scheduling interval and the duration of the scheduling interval.

[0223] As an example, all or part of the information indicated in the request message may be pre-configured by the network device, for example, configured by the network device via an RRC reconfiguration message. The terminal device can be activated via the request message. In this way, the terminal device can send a request message to the network device more quickly via low-layer signaling without carrying the scheduling interval configuration information. The network device can also respond quickly via low-layer signaling, thereby ensuring that the terminal device can activate the scheduling slot in the first communication system before the cell signal quality of the source cell falls below a threshold. This allows the resources required for DAPS handover in the first communication system to be released more quickly on the second network device, avoiding link drop due to source primary cell group radio link failure in the first communication system.

[0224] For example, the request message could be a MAC CE or a physical layer message. Alternatively, the request message could also be an RRC message.

[0225] In one implementation, the terminal device can enable a timer when sending the request message, hereinafter referred to as Timer A.

[0226] S704, after receiving the response message to the request message in the second communication system, the terminal device performs a DAPS handover in the first communication system. This DAPS handover in the first communication system can be performed within a scheduling interval.

[0227] In one implementation, the terminal device can receive a response message to a request message in a second communication system as a second user.

[0228] In one possible implementation, the terminal device may further determine that no response message is received within a first time period after sending the request message (e.g., during the timer A period), or that the signal quality of the source cell in the first communication system is below a first threshold. In this case, the terminal device may employ... Figure 4 or Figure 5 The method performs a handover within the first communication system, that is, it can terminate communication with the source cell in the first communication system and hand over to the target cell within the first communication system. For details, please refer to [link / reference needed]. Figure 4 The relevant explanations will not be repeated here.

[0229] In another possible implementation, the terminal device may also determine that no response message is received within a first duration after sending the request message (e.g., during the timer A period), or that the signal quality of the source cell in the first communication system is below a first threshold. In this case, the terminal device may also perform a DAPS handover in the first communication system, and during the DAPS handover in the first communication system, data transmission on a first resource in the second communication system is interrupted, where data transmission on the first resource in the second communication system conflicts with the DAPS handover in the first communication system.

[0230] In this embodiment of the application, when the terminal device has resource conflicts with the DAPS handover in the first communication device and the services in the second communication system, it can request a scheduling interval from the network device of the second communication system to suspend the service transmission in the second communication system, thereby avoiding packet loss in the service transmission in the second communication system.

[0231] It should be noted that, Figure 7 The request scheduling interval in the method can be an optional step. In specific implementation, the terminal device can also perform DAPS handover in the first communication system when it is determined that the available capabilities of the first communication system cannot support DAPS handover, and suspend the interrupted data transmission on the first resource of the second communication system during the DAPS handover of the first communication system.

[0232] Optionally, the terminal device can determine the request scheduling interval on the second communication system based on information such as the latency requirements or service priorities of services on the first and second communication systems. For example, when a latency-sensitive service is being performed on the first communication system, the terminal device can prioritize performing DAPS handover on the first communication system and interrupt transmission on the second communication system during the DAPS handover to ensure that the latency requirements of services on the first communication network are met.

[0233] To better understand the solution provided in this application, the switching process is described below as an example.

[0234] like Figure 8 As shown, the switching process includes:

[0235] S801, the terminal device sends a measurement report to the first network device. The measurement report may carry measurement results for the serving cell and at least one neighboring cell.

[0236] S802, the first network device makes the handover decision.

[0237] S803, the first network device sends a handover request message to the second network device.

[0238] S804, the second network device performs access control.

[0239] S805, the second network device sends a handover request response message to the first network device.

[0240] S806, the first network device sends the first message to the terminal device.

[0241] S807, the first network device sends an early state transition message to the second network device.

[0242] S808, The terminal device determines that the capabilities available for the first communication system cannot support DAPS handover.

[0243] For details of steps S801 to S808, please refer to [link / reference]. Figure 5 The descriptions of S501 to S508 in the method are repeated hereafter.

[0244] S809, the terminal device sends a request message to the third network device.

[0245] This request message is used to request a scheduling interval. For details on this request message, please refer to the relevant description in S703; it will not be repeated here.

[0246] S810, the terminal device starts timer A. Execute S811 to S812, or execute S813.

[0247] S811, during the timing of Timer A, or before the cell signal quality of the source cell of the first system is less than the threshold, the terminal device receives a response message to the request message.

[0248] S812, the terminal device performs DAPS handover in the first communication system within the scheduling interval.

[0249] S813, During the timing of Timer A, or before the cell signal quality of the source cell of the first system is less than the threshold, the terminal device does not receive a response message to the request message.

[0250] S814, the terminal device terminates communication with the source cell in the first communication system and switches to the target cell in the first communication system.

[0251] For details on S814, please refer to [link / reference]. Figure 5 The relevant descriptions of S509 to S516 will not be repeated here.

[0252] In this embodiment of the application, when the terminal device has resource conflicts with the DAPS handover in the first communication device and the services in the second communication system, it can request a scheduling interval from the network device of the second communication system to suspend the service transmission in the second communication system, thereby avoiding packet loss in the service transmission in the second communication system.

[0253] Another communication method is provided below. In scenarios where the terminal device receives a DAPS handover instruction in both the first and second communication systems, the method determines the DAPS handover priority between the two systems based on factors such as the services in the first and second systems, or the reception times of the first and second messages. The handover behavior in the two systems is then determined according to this priority, thereby avoiding communication interruptions and packet loss. This communication method is described in detail below.

[0254] See Figure 9 This is a flowchart illustrating a communication method provided in this application. The method includes:

[0255] S901, the terminal device receives the first message in the first communication system. Specifically, the terminal device can receive the first message as the first user.

[0256] The first message is used to instruct the terminal device to perform a first DAPS handover between the first source cell and the first target cell in the first communication system.

[0257] S902, the terminal device receives a second message in the second communication system. Specifically, the terminal device can receive the second message as a second user.

[0258] The second message is used to instruct the terminal device to perform a second DAPS handover between the second source cell and the second target cell in the second communication system, and the second communication system corresponds to the second user identity.

[0259] In one implementation, the terminal device may receive the second message after receiving the first message and before handing over to the first target cell in the first communication system, for example, receiving the second message during a first DAPS handover in the first communication system. Alternatively, the terminal device may receive the first message after receiving the second message and before handing over to the second target cell in the second communication system, for example, receiving the first message during a second DAPS handover in the second communication system.

[0260] In another implementation, the terminal device can also receive the first message and the second message simultaneously.

[0261] S903, the terminal device performs a first DAPS handover in the first communication system and / or a second DAPS handover in the second communication system based on at least one of the following: the terminal device's capabilities, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message.

[0262] The capabilities of the terminal devices can be found in [reference]. Figure 4 The descriptions of the capabilities of terminal devices in the text will not be repeated here.

[0263] In one implementation, the terminal device can determine the priority of DAPS handover in the first communication system and the priority of DAPS handover in the second communication system based on at least one of the following: the capabilities of the terminal device, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message. The terminal device can first perform a DAPS handover with higher priority, and after performing the higher-priority DAPS handover, perform another DAPS handover. For example, assuming the priority of the first DAPS handover in the first communication system is higher than the priority of the second DAPS handover in the second communication system, the terminal device can first perform the first DAPS handover in the first communication system, and after performing the first DAPS handover in the first communication system, perform the second DAPS handover in the second communication system.

[0264] In another implementation, the terminal device can determine the priority of DAPS handover in the first communication system and the priority of DAPS handover in the second communication system based on at least one of the following: the capabilities of the terminal device, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message. For high-priority DAPS handovers, the terminal device can perform DAPS handover in the corresponding communication system. For low-priority DAPS handovers, the terminal device can suspend communication with the source cell in the corresponding communication system and perform a basic handover. For example, assuming that the priority of the first DAPS handover in the first communication system is higher than the priority of the second DAPS handover in the second communication system, the terminal device can perform a DAPS handover in the first communication system, interrupt communication with the second source cell in the second communication system, and hand over to the second target cell, that is, it can perform a basic handover in the second communication system. The handover behavior in the second communication system can be found in [reference needed]. Figure 4 or Figure 5 The relevant descriptions will not be repeated here.

[0265] Based on either of the above two implementation methods, when the first communication system satisfies at least one of the following, the priority of the first DAPS handover in the first system is higher than the priority of the second DAPS handover in the second communication system: the reception time of the first message and the reception time of the second message satisfy a preset relationship; the priority of the service in the first communication system is higher than the priority of the service in the second communication system; or the latency requirement of the service in the first communication system is higher than the latency requirement of the service in the second communication system. The higher latency requirement of the service can be understood as the shorter latency required for the service.

[0266] For example, the above-mentioned preset relationship can be: the reception time of the first message is earlier than the reception time of the second message;

[0267] Alternatively, the above-mentioned preset relationship can also be: the second message is received earlier than the first message.

[0268] The following example illustrates how the priority of the first DAPS handover in the first system and the priority of the second DAPS handover in the second communication system are determined based on the reception time of the first message and the reception time of the second message.

[0269] In a specific example, for the communication system corresponding to the later received message in the first and second messages, the terminal device can switch using the method described in Embodiment 1, and DAPS switching can be performed in another communication system.

[0270] In another specific example, for the communication system corresponding to the earlier received message in the first and second messages, the terminal device can switch using the method described in Embodiment 1, and DAPS switching can be performed in another communication system.

[0271] In another specific example, for the communication system corresponding to the earlier received message in the first and second messages, the terminal device can first perform DAPS handover in that communication system, and after completing the DAPS handover in that communication system, perform DAPS handover in another communication system.

[0272] In another specific example, for the communication system corresponding to the later received message in the first and second messages, the terminal device can first perform DAPS handover in that communication system, and after completing the DAPS handover in that communication system, perform DAPS handover in another communication system.

[0273] In one possible scenario, the terminal device's capabilities only support DAPS handover in one communication system and non-DAPS handover in another. Alternatively, it can be understood that the terminal device's capabilities only support receiving downlink data and / or sending uplink data with both the source and target cells during handover in one communication system, and receiving downlink data and / or sending uplink data with only one cell (such as the target cell) during handover in another communication system.

[0274] To better understand the solution provided in this application, the switching process is described below as an example.

[0275] like Figure 10 As shown, the switching process includes:

[0276] S1001, the first network device sends a first message to the terminal device in the first communication system.

[0277] The first network device is the network device that the terminal device accesses in the first communication system, or it can be understood as the network device that the terminal device accesses as the first user.

[0278] For more information, please refer to the first news article. Figure 4 The relevant explanation from China First News.

[0279] Optionally, after step S1001, the first network device may send an early status transfer message to the second network device.

[0280] The second network device can be the network device that the terminal device will access in the first communication system, or it can be understood as the network device corresponding to the target cell (i.e., the first target cell) of the terminal device in the first communication system.

[0281] S1002, the third network device sends a second message to the terminal device in the second communication system.

[0282] The third network device is the network device that the terminal device accesses in the second communication system, or it can be understood as the network device that the terminal device accesses as a second user.

[0283] The second message is similar to the first message; please refer to [the original text]. Figure 4 The relevant explanation from China First News.

[0284] Optionally, after step S1002, the third network device may send an early state transition message to the fourth network device.

[0285] The fourth network device can be the network device that the terminal device will access in the second communication system, or it can be understood as the network device corresponding to the target cell (i.e., the second target cell) of the terminal device in the second communication system.

[0286] S1003, the terminal device determines that the priority of the first DAPS handover in the first communication system is higher than the priority of the second DAPS handover in the second communication system.

[0287] For details on S1003, please refer to the relevant description in S903. Repeated points will not be repeated here.

[0288] S1004, the terminal device sends an instruction message to the third network device.

[0289] For details, please refer to the instructions. Figure 4 The relevant description of the first indication information in the method.

[0290] S1005, the terminal device performs a basic handover in the second communication system.

[0291] Specifically, the terminal device can suspend communication with the second source cell and switch to the second target cell in the second communication system.

[0292] For details, please refer to S1005. Figure 4 The relevant descriptions of S403 and S404 in the method will not be repeated here.

[0293] S1006, the terminal device performs DAPS handover in the first communication system.

[0294] It should be noted that this application does not limit the execution order of S1004-S1005 and S1006.

[0295] In this embodiment, the handover priority of DAPS in two communication systems is determined, and the handover behavior in the two communication systems is determined according to the priority, thereby avoiding communication interruptions and packet loss in the two communication systems. This application prioritizes DAPS handover of the communication system with higher service priority and higher service latency requirements, which can improve user experience.

[0296] Based on the same concept as the method embodiments, this application provides a communication device, the structure of which can be as follows: Figure 11 As shown, it includes a communication module 1101 and a processing module 1102.

[0297] In one embodiment, the communication device can specifically be used to implement Figure 4 In the embodiments, the terminal device executes a method. This device can be the terminal device itself, or a chip or chipset within the terminal device, or a part of a chip that performs the relevant method function. Specifically, the communication module 1101 is configured to receive a first message in a first communication system, the first message instructing the terminal device to perform a DAPS handover between a source cell and a target cell in the first communication system. The processing module 1102 is configured to determine that the capabilities available to the first communication system cannot support DAPS handover, and that the terminal device's capabilities are used for communication in the first and second communication systems, the first communication system corresponding to a first user identity and the second communication system corresponding to a second user identity. Furthermore, it is configured to terminate communication with the source cell in the first communication system and to handover to the target cell in the first communication system.

[0298] Optionally, when processing module 1102 determines that the capabilities available for the first communication system cannot support DAPS handover, it is specifically configured to: determine that the carrier aggregation capability and / or dual connectivity capability available for the first communication system cannot support DAPS handover.

[0299] Optionally, the first message carries configuration information for N radio bearers, and the configuration information for the N radio bearers carries DAPS configuration, where N is an integer greater than 0. The processing module 1102 is further configured not to configure the N radio bearers as DAPS bearers.

[0300] Optionally, when the processing module 1102 terminates communication with the source cell in the first communication system, it is specifically used to: release the RRC connection with the source cell; and / or suspend the transmission and reception of the DRB in the source primary cell group; and / or determine that the radio link of the source primary cell or the source primary cell group in the first communication system has failed.

[0301] Optionally, the communication module 1101 is further configured to: send indication information to the source cell in the first communication system, the indication information being used to indicate that communication with the source cell has been or will be terminated.

[0302] In one embodiment, the communication device can specifically be used to implement Figure 4 In the embodiments, the method executed by the first network device can be the network device itself, or a chip or chipset within the network device, or a part of the chip used to execute the relevant method function. Specifically, the communication module 1101 is used to send a first message to the terminal device, wherein the first message instructs the terminal device to perform a DAPS handover between a source cell and a target cell, the source cell belonging to the first network device. It also receives first indication information sent by the terminal device, the first indication information indicating that communication with the source cell has been or will be terminated. The processing module 1102 stops the source cell from scheduling data for the terminal device.

[0303] Optionally, the communication module 1101 is also used to send second indication information to the second network device. The second indication information is used to indicate that the terminal device has stopped or is about to stop communication with the source cell, and the target cell belongs to the second network device.

[0304] In one embodiment, the communication device can specifically be used to implement Figure 6 In the embodiments, the terminal device executes a method. This device can be the terminal device itself, or a chip or chipset within the terminal device, or a part of a chip used to execute related method functions. Specifically, the processing module 1102 is used to determine that a first event has occurred; the communication module 1101 is used to send indication information in a first communication system. This indication information is used to update the DAPS capability of the terminal device in the first communication system. The indication information is effective for any combination of frequency bands of the terminal device, or it is effective for the first frequency band in a first combination of frequency bands. The terminal device supports communication between the first communication system and a second communication system. The first communication system corresponds to a first user identity, and the second communication system corresponds to a second user identity.

[0305] In one embodiment, the communication device can specifically be used to implement Figure 7In the embodiments described, the terminal device executes a method. This device can be the terminal device itself, or a chip or chipset within the terminal device, or a part of a chip used to execute the relevant method function. Specifically, a communication module 1101 is configured to receive a first message in a first communication system, wherein the first message instructs the terminal device to perform a DAPS handover between a source cell and a target cell in the first communication system. A processing module 1102 is configured to determine that the capabilities available to the first communication system cannot support DAPS handover, and that the terminal device's capabilities are used for communication in the first and second communication systems, where the first communication system corresponds to a first user identity and the second communication system corresponds to a second user identity. The communication module 1101 is further configured to send a request message in the second communication system, the request message requesting a scheduling interval, wherein the request message indicates at least one of the following: the purpose of requesting the scheduling interval, the frequency band identifier corresponding to the scheduling interval, the cell group identifier corresponding to the scheduling interval, and the cell identifier corresponding to the scheduling interval. After receiving a response message to the request message in the second communication system, a DAPS handover is performed in the first communication system during the scheduling interval.

[0306] Optionally, the processing module 1102 is further configured to determine that no response message is received within a first time period after sending the request message, or that the signal quality of the source cell in the first communication system is lower than a first threshold; and to terminate communication with the source cell in the first communication system; and to switch to the target cell in the first communication system.

[0307] Optionally, the communication module 1101 is also used to send indication information to the source cell in the first communication system, the indication information being used to indicate that communication with the source cell has been suspended or is about to be suspended.

[0308] Optionally, the processing module 1102 is further configured to determine that no response message is received within a first time period after sending the request message, or that the signal quality of the source cell in the first communication system is lower than a first threshold; and to perform a DAPS handover in the first communication system, and interrupt data transmission on a first resource in the second communication system during the DAPS handover in the first communication system, wherein the data transmission on the first resource in the second communication system conflicts with the DAPS handover in the first communication system.

[0309] In one embodiment, the communication device can specifically be used to implement Figure 9In the embodiments, the terminal device executes a method. The device may be the terminal device itself, or a chip or chipset within the terminal device, or a part of a chip used to execute related method functions. Specifically, the communication module 1101 is configured to receive a first message in a first communication system, wherein the first message instructs the terminal device to perform a first DAPS handover between a first source cell and a first target cell in the first communication system, the first communication system corresponding to a first user identity; and to receive a second message in a second communication system, wherein the second message instructs the terminal device to perform a second DAPS handover between a second cell and a second target cell in the second communication system, the second communication system corresponding to a second user identity. The processing module 1102 performs the first DAPS handover in the first communication system and / or the second DAPS handover in the second communication system based on at least one of the following: the capabilities of the terminal device, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message.

[0310] Optionally, processing module 1102 is specifically configured to: perform a first DAPS handover in the first communication system and / or perform a second DAPS handover in the second communication system based on at least one of the following: the capabilities of the terminal device, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message, including: the terminal device determining that the priority of the first DAPS handover on the first communication system is higher than the priority of the second DAPS handover on the second communication system based on at least one of the following: the capabilities of the terminal device, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message. And, perform the first DAPS handover in the first communication system. And, after performing the first DAPS handover, perform the second DAPS handover in the second communication system.

[0311] Optionally, processing module 1102 is specifically configured to: perform a first DAPS handover in the first communication system and / or perform a second DAPS handover in the second communication system according to at least one of the following: the capabilities of the terminal device, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message, including: the terminal device determining that the priority of the first DAPS handover on the first communication system is higher than the priority of the second DAPS handover on the second communication system according to at least one of the following: the capabilities of the terminal device, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message. And, perform the first DAPS handover in the first communication system; suspend communication with the second source cell in the second communication system; and, handover to the second target cell in the second communication system.

[0312] Optionally, the processing module 1102, when determining that the priority of the first DAPS handover on the first communication system is higher than the priority of the second DAPS handover on the second communication system based on at least one of the following: the hardware capabilities of the terminal device, the services in the first communication system and the services in the second communication system, or the reception time of the first message and the reception time of the second message, specifically performs the following: determining that at least one of the following is satisfied: a preset relationship is satisfied based on the reception time of the first message and the reception time of the second message, the priority of the services in the first communication system is higher than the priority of the services in the second communication system, or the latency requirement of the services in the first communication system is higher than the latency requirement of the services in the second communication system; and determining that at least one of the following is satisfied: a preset relationship is satisfied based on the reception time of the first message and the reception time of the second message, the priority of the services in the first communication system is higher than the priority of the services in the second communication system, or the latency requirement of the services in the first communication system is higher than the latency requirement of the services in the second communication system.

[0313] The module division in this application embodiment is illustrative and represents only one logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional modules in the various embodiments of this application can be integrated into a single processor, exist as separate physical entities, or be integrated into a single module. The integrated modules described above can be implemented in hardware or as software functional modules. It is understood that the functions or implementations of the modules in the embodiments of this application can be further described in the relevant descriptions of the method embodiments.

[0314] In one possible approach, the communication device can be as follows: Figure 12 As shown, the device can be a communication device or a chip within a communication device, wherein the communication device can be the terminal device in the above embodiments or the network device in the above embodiments. The device includes a processor 1201 and a communication interface 1202, and may also include a memory 1203. The processing module 1102 can be the processor 1201. The communication module 1101 can be the communication interface 1202.

[0315] The processor 1201 can be a CPU, a digital processing unit, or something similar. The communication interface 1202 can be a transceiver, an interface circuit such as a transceiver circuit, or a transceiver chip, etc. The device also includes a memory 1203 for storing the program executed by the processor 1201. The memory 1203 can be non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), or it can be volatile memory, such as random-access memory (RAM). The memory 1203 can be any other medium capable of carrying or storing desired program code in the form of instructions or data structures that can be accessed by a computer, but is not limited to this.

[0316] The processor 1201 is used to execute the program code stored in the memory 1203, specifically to perform the actions of the aforementioned processing module 1102, which will not be described in detail here. The communication interface 1202 is specifically used to perform the actions of the aforementioned communication module 1101, which will not be described in detail here.

[0317] This application embodiment does not limit the specific connection medium between the communication interface 1202, processor 1201, and memory 1203. This application embodiment... Figure 12 The memory 1203, processor 1201, and communication interface 1202 are connected via a bus 1204. Figure 12 The connections between other components are shown in bold lines only and are not intended to be limiting. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, Figure 12 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0318] This application also provides a computer-readable storage medium for storing computer software instructions required to execute the processor, including a program required to execute the processor.

[0319] This application also provides a communication system, including methods for implementing... Figure 4 In the embodiments, a communication device for implementing terminal device functions and a communication device for implementing terminal device functions are provided. Figure 4 The communication device in the embodiment is a first network device.

[0320] This application also provides a communication system, including methods for implementing... Figure 6 In the embodiments, a communication device for implementing terminal device functions and a communication device for implementing terminal device functions are provided. Figure 6 In the embodiments, a communication device for implementing the functions of a first network device and a communication device for implementing the functions of a first network device are described. Figure 6 The communication device in the embodiment is a third network device function.

[0321] This application also provides a communication system, including methods for implementing... Figure 7 In the embodiments, a communication device for implementing terminal device functions and a communication device for implementing terminal device functions are provided. Figure 7 The communication device in the embodiment is a first network device.

[0322] This application also provides a communication system, including methods for implementing... Figure 9 In the embodiments, a communication device for implementing terminal device functions and a communication device for implementing terminal device functions are provided. Figure 9 In the embodiments, a communication device for implementing the functions of a first access network device and a communication device for implementing Figure 9 The communication device in the embodiment is a third network device function.

[0323] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0324] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0325] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0326] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

Claims

1. A communication method, characterized in that, The method includes: The terminal device receives a first message in the first communication system, wherein the first message is used to instruct the terminal device to perform a dual-activation protocol stack (DAPS) handover between the source cell and the target cell in the first communication system; The terminal device determines that the capabilities available for the first communication system cannot support the DAPS handover. The capabilities of the terminal device are used to communicate in the first communication system and the second communication system. The first communication system corresponds to the first user identity, and the second communication system corresponds to the second user identity. The terminal device terminates communication with the source cell in the first communication system; The terminal device switches to the target cell in the first communication system.

2. The method as described in claim 1, characterized in that, The terminal device determines that the capabilities available to the first communication system cannot support the DAPS handover, including: The terminal device determines that the carrier aggregation capability and / or dual connectivity capability available for the first communication system cannot support the DAPS handover.

3. The method as described in claim 1 or 2, characterized in that, The first message carries configuration information for N radio bearers, and the configuration information for the N radio bearers carries DAPS configuration, where N is an integer greater than 0; The method further includes: Do not configure the N radio bearers as DAPS bearers.

4. The method as described in claim 1 or 2, characterized in that, The termination of communication between the terminal device and the source cell in the first communication system includes: The terminal device releases the Radio Resource Control (RRC) connection with the source cell; And / or, the terminal device is suspended from transmitting and receiving the data radio bearer (DRB) of the source primary cell group; And / or, the terminal device determines that the radio link of the source master cell or source master cell group in the first communication system has failed.

5. The method as described in claim 1 or 2, characterized in that, The method further includes: If the terminal device successfully accesses the target cell, the terminal device sends a first message to the target cell, wherein the first message indicates that the terminal device has terminated communication with the source cell due to resource conflict.

6. The method as described in claim 1 or 2, characterized in that, The method further includes: The terminal device sends indication information to the source cell in the first communication system, the indication information being used to indicate that communication with the source cell has been suspended or is about to be suspended.

7. A communication method, characterized in that, The method includes: A first network device sends a first message to a terminal device, wherein the first message is used to instruct the terminal device to perform a dual-activation protocol stack (DAPS) handover between a source cell and a target cell in a first communication system, and the source cell belongs to the first network device. The first network device receives first indication information from the terminal device, the first indication information being used to indicate that communication with the source cell has been suspended or is about to be suspended; wherein, the suspension of communication with the source cell is triggered by the terminal device determining that the capabilities available to the first communication system cannot support the DAPS handover. The first network device stops data scheduling for the terminal device in the source cell.

8. The method as described in claim 7, characterized in that, The method further includes: The first network device sends a second indication message to the second network device. The second indication message is used to indicate that the terminal device has stopped or is about to stop communication with the source cell, and the target cell belongs to the second network device.

9. The method as described in claim 8, characterized in that, The second indication information is sent to the second network device via a sequence number state transition message.

10. A communication method, characterized in that, The method includes: The terminal device receives a first message in the first communication system, wherein the first message is used to instruct the terminal device to perform a dual-activation protocol stack (DAPS) handover between the source cell and the target cell in the first communication system; The terminal device determines that the capabilities available for the first communication system cannot support the DAPS handover. The capabilities of the terminal device are used to communicate in the first communication system and the second communication system. The first communication system corresponds to the first user identity, and the second communication system corresponds to the second user identity. The terminal device sends a request message in the second communication system. The request message is used to request a scheduling interval, wherein the request message indicates at least one of the following: the purpose of requesting the scheduling interval, the frequency band identifier corresponding to the scheduling interval, the cell group identifier corresponding to the scheduling interval, and the cell identifier corresponding to the scheduling interval. After receiving the response message of the request message in the second communication system, the terminal device performs the DAPS handover in the first communication system during the scheduling interval.

11. The method as described in claim 10, characterized in that, The method further includes: The terminal device determines that it has not received the response message within a first time period after sending the request message, or that the signal quality of the source cell in the first communication system is lower than a first threshold. The terminal device terminates communication with the source cell in the first communication system; The terminal device switches to the target cell in the first communication system.

12. The method as described in claim 11, characterized in that, The method further includes: The terminal device sends indication information to the source cell in the first communication system, the indication information being used to indicate that communication with the source cell has been suspended or is about to be suspended.

13. The method as described in claim 10, characterized in that, The method further includes: The terminal device determines that it has not received the response message within a first time period after sending the request message, or that the signal quality of the source cell in the first communication system is lower than a first threshold. The terminal device performs the DAPS handover in the first communication system, and during the DAPS handover in the first communication system, the data transmission on the first resource in the second communication system is interrupted, and the data transmission on the first resource in the second communication system conflicts with the DAPS handover in the first communication system.

14. The method according to any one of claims 10-13, characterized in that, The request message is a Media Access Control (MAC) control unit (CE) or a physical layer message.

15. The method according to any one of claims 10-13, characterized in that, The DAPS handover in the first communication system conflicts with the services of the primary cell in the second communication system, and the cell identifier corresponding to the scheduling interval is the primary cell identifier in the second communication system. And / or, the DAPS handover in the first communication system conflicts with the services of the first secondary cell or the first secondary cell group in the second communication system, and the cell identifier corresponding to the scheduling interval is the first secondary cell identifier or the first secondary cell group identifier in the second communication system. And / or, the DAPS handover in the first communication system conflicts with the service on the first frequency band in the second communication system, and the frequency band identifier corresponding to the scheduling interval is the identifier of the first frequency band.

16. The method according to any one of claims 10-13, characterized in that, The purpose of requesting the scheduling interval is to perform the DAPS handover in the first communication system.

17. A communication device, characterized in that, The device includes: The transceiver module is configured to receive a first message in a first communication system, wherein the first message is configured to instruct the terminal device to perform a dual-active protocol stack (DAPS) handover between a source cell and a target cell in the first communication system. The communication module is also configured to determine that the capabilities available for the first communication system cannot support the DAPS handover, and the capabilities of the terminal device are used to communicate in the first communication system and the second communication system, wherein the first communication system corresponds to a first user identity and the second communication system corresponds to a second user identity; And, terminate communication with the source cell in the first communication system; And, in the first communication system, switch to the target cell.

18. The apparatus as claimed in claim 17, characterized in that, When the communication module determines that the capabilities available to the first communication system cannot support the DAPS switching, it is specifically used for: It was determined that the carrier aggregation capability and / or dual connectivity capability available for the first communication system could not support the DAPS handover.

19. The apparatus as claimed in claim 17 or 18, characterized in that, The first message carries configuration information for N radio bearers, and the configuration information for the N radio bearers carries DAPS configuration, where N is an integer greater than 0; The communication module is also used for: Do not configure the N radio bearers as DAPS bearers.

20. The apparatus as claimed in claim 17 or 18, characterized in that, When the communication module terminates communication with the source cell in the first communication system, it is specifically used for: Release the Radio Resource Control (RRC) connection with the source cell; And / or, suspending the transmission and reception of the data radio bearer DRB in the source primary cell group; And / or, determine that the source master cell or source master cell group radio link in the first communication system has failed.

21. The apparatus as claimed in claim 17 or 18, characterized in that, The communication module is also used for: If the communication module successfully accesses the target cell, it sends a first message to the target cell, wherein the first message indicates that the terminal device has terminated communication with the source cell due to resource conflict.

22. The apparatus as claimed in claim 17 or 18, characterized in that, The communication module is also used for: Send indication information to the source cell in the first communication system, the indication information being used to indicate that communication with the source cell has been suspended or is about to be suspended.

23. A communication device, characterized in that, The device includes: The transceiver module is used to send a first message to the terminal device, wherein the first message is used to instruct the terminal device to perform a dual-active protocol stack (DAPS) handover between the source cell and the target cell in the first communication system, and the source cell belongs to the first network device; In addition, the terminal device receives first indication information, which indicates that communication with the source cell has been suspended or is about to be suspended; wherein the suspension of communication with the source cell is triggered by the terminal device determining that the capabilities available to the first communication system cannot support the DAPS handover. A communication module is used to stop data scheduling for the terminal device in the source cell.

24. The apparatus as claimed in claim 23, characterized in that, The transceiver module is also used for: Send a second indication message to a second network device, the second indication message being used to indicate that the terminal device has stopped or is about to stop communication with the source cell, the target cell belonging to the second network device.

25. The apparatus as claimed in claim 24, characterized in that, The second indication information is sent to the second network device via a sequence number state transition message.

26. A communication device, characterized in that, The device includes: The transceiver module is configured to receive a first message in a first communication system, wherein the first message is configured to instruct the terminal device to perform a dual-active protocol stack (DAPS) handover between a source cell and a target cell in the first communication system. A communication module is used to determine that the capabilities available for the first communication system cannot support the DAPS handover. The capabilities of the terminal device are used to communicate in the first communication system and the second communication system. The first communication system corresponds to a first user identity, and the second communication system corresponds to a second user identity. The transceiver module is further configured to send a request message in the second communication system. The request message is used to request a scheduling interval, wherein the request message indicates at least one of the following: the purpose of requesting the scheduling interval, the frequency band identifier corresponding to the scheduling interval, the cell group identifier corresponding to the scheduling interval, and the cell identifier corresponding to the scheduling interval. And, after receiving the response message of the request message in the second communication system, the DAPS handover is performed in the first communication system during the scheduling interval.

27. The apparatus as claimed in claim 26, characterized in that, The communication module is also used for: If the response message is not received within a first time period after the request message is sent, or if the signal quality of the source cell in the first communication system is lower than a first threshold; Suspend communication with the source cell in the first communication system; Switch to the target cell in the first communication system.

28. The apparatus as claimed in claim 27, characterized in that, The transceiver module is also used for: Send indication information to the source cell in the first communication system, the indication information being used to indicate that communication with the source cell has been suspended or is about to be suspended.

29. The apparatus as claimed in claim 26, characterized in that, The communication module is also used for: If the response message is not received within a first time period after the request message is sent, or if the signal quality of the source cell in the first communication system is lower than a first threshold; The DAPS handover is performed in the first communication system, and data transmission on a first resource in the second communication system is interrupted during the DAPS handover in the first communication system, wherein the data transmission on the first resource in the second communication system conflicts with the DAPS handover in the first communication system.

30. The apparatus according to any one of claims 26-29, characterized in that, The request message is a Media Access Control (MAC) control unit (CE) or a physical layer message.

31. The apparatus according to any one of claims 26-29, characterized in that, The DAPS handover in the first communication system conflicts with the services of the primary cell in the second communication system, and the cell identifier corresponding to the scheduling interval is the primary cell identifier in the second communication system. And / or, the DAPS handover in the first communication system conflicts with the services of the first secondary cell or the first secondary cell group in the second communication system, and the cell identifier corresponding to the scheduling interval is the first secondary cell identifier or the first secondary cell group identifier in the second communication system. And / or, the DAPS handover in the first communication system conflicts with the service on the first frequency band in the second communication system, and the frequency band identifier corresponding to the scheduling interval is the identifier of the first frequency band.

32. The apparatus according to any one of claims 26-29, characterized in that, The purpose of requesting the scheduling interval is to perform the DAPS handover in the first communication system.

33. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store computer instructions that, when executed on a computer, cause the computer to perform the method as described in any one of claims 1 to 16.

Images