Communication method and communication apparatus

Abstract

The present application provides a communication method, comprising: a first network device determines that a terminal device is interested in clock-related information; when the terminal device is in an inactive state, the first network device sends a first message to a second network device, wherein the first message indicates sending the clock-related information to the terminal device within the coverage area of the second network device. To avoid the problem that the second network device cannot sense the terminal device that is in the inactive state and cannot provide the clock-related information to the terminal device, by means of the first message, the second network device is instructed to send the clock-related information to the terminal device within the coverage area of the second network device, ensuring that even if the terminal device that is in the inactive state and interested in the clock-related information moves out of the coverage area of the first network device (for example, within the coverage area of the second network device), the terminal device can still acquire the clock-related information, making a related application / service operate normally.

Description

Communication method and communication device

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on December 29, 2023, with application number 202311867818.9 and invention name “Communication Method and Communication Device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of communications, and more specifically, to a communication method and a communication device. Background Art

[0003] The fifth generation (5G) system, as defined in the current 3rd Generation Partnership Project (3GPP) standards, supports high-precision timing services over the air. Network devices can provide 5G high-precision time to terminal devices via air interface messages, enabling high-precision clock synchronization between the terminal and network devices.

[0004] Currently, the radio access network notification area (RNA) configured for an inactive terminal device contains cells corresponding to multiple network devices. When a terminal device enters the Inactive state, only the network device that provides services to the terminal device (or called the last serving gNB) can sense whether the terminal device needs to obtain clock-related information. Other network devices within the coverage area of ​​the RNA cannot sense whether the terminal device needs to obtain clock-related information. If the Inactive terminal device moves and moves out of the coverage area of ​​the last serving gNB, the last serving gNB cannot provide clock-related information to the terminal device, and other network devices cannot sense whether the terminal device needs to obtain clock-related information, resulting in the terminal device being unable to obtain clock-related information or unable to sense whether the clock-related information has changed, causing the terminal device's related applications to fail to work normally due to the loss of clock-related information. Summary of the Invention

[0005] The present application provides a communication method and a communication device, which enable an inactive terminal device that is interested in clock-related information to obtain clock-related information, thereby ensuring the normal operation of applications / services related to the terminal device.

[0006] In a first aspect, a communication method is provided. The method can be performed by a first network device. The first network device here can refer to the first network device itself or a processor, module, chip, or chip system in the first network device that implements the method, and this application does not limit this. The method includes:

[0007] The first network device determines that the terminal device is interested in clock-related information; when the terminal device is in an inactive state, the first network device sends a first message to the second network device, and the first message indicates that clock-related information is sent to the terminal device within the coverage area of ​​the second network device.

[0008] It should be understood that the terminal device is interested in clock-related information, which can be understood as the normal operation of the relevant applications or related services of the terminal device requiring clock-related information, or the terminal device has a demand for clock-related information, or the terminal device needs to obtain clock-related information.

[0009] It should be understood that the first network device sends the first message to the second network device. Whether the inactive terminal device is within the coverage of the second network device is not limited in this application.

[0010] According to the method provided in the present application, the first network device determines that the terminal device is a terminal device that is interested in clock-related information. When the terminal device is in an inactive state, the first network device sends the first message to the second network device. When the terminal device that is interested in clock-related information is in an inactive state, the first network device indicates to the second network device through the first message that it is a terminal device, and sends clock-related information within the coverage of the second network device. This avoids the problem that when an inactive terminal device moves to the coverage of the second network device, the second network device cannot perceive the terminal device and cannot provide the terminal device with clock-related information in a timely manner. It ensures that even if an inactive terminal device that is interested in clock-related information moves out of the coverage of the serving network device, it can still obtain clock-related information, thereby ensuring the normal operation of the relevant applications / services of the terminal device.

[0011] With reference to the first aspect, in some possible implementations, the first network device determining that the terminal device is interested in clock-related information includes:

[0012] The first network device receives first indication information from a third network device, where the first indication information is used to indicate that the terminal device is interested in the clock-related information. The third network device is a network device that provided services to the terminal device before the terminal device accessed the first network device. The first network device determines, based on the first indication information, that the terminal device is interested in the clock-related information.

[0013] It should be understood that the first network device receives the first indication information from the last network device (eg, the third network device) that provides coverage for the terminal device, and determines that the terminal device is interested in clock-related information.

[0014] In combination with the first aspect, in some possible implementations, the first network device receives second indication information from the terminal device in a connected state, and the second indication information is used to indicate that the terminal device is interested in the clock-related information; the first network device determines that the terminal device is interested in the clock information based on the second indication information.

[0015] It should be understood that when the terminal device is in a connected state, the terminal device may indicate to the first network device that the terminal device is interested in clock-related information.

[0016] In combination with the first aspect, in some possible implementation methods, the method also includes: the first network device sends a second message to the terminal device, the second message instructing the terminal device to enter an inactive state from a connected state, the second message includes information indicating a first RNA, and the first RNA includes the coverage range of the second network device.

[0017] It should be understood that the first RNA includes the coverage of the second network device, and the first RNA includes all or part of the coverage of the second network device. Alternatively, it can be understood that the first RNA includes one or more cells managed by the second network device.

[0018] It should be understood that when the first network device sends the first message to the second network device, the first network device also sends a second message to the terminal device, where the second message is used to instruct the terminal device to enter the inactive state from the connected state. The second message may also include information indicating the first RNA configured by the first network device for the terminal device.

[0019] It should also be understood that the second message can be carried in a radio resource control RRC release message sent by the first network device to the terminal device, or sent through separate signaling.

[0020] In combination with the first aspect, in some possible implementations, the first message includes first identification information of the terminal device and / or coverage information of the second network device.

[0021] Optionally, the first message may include first identification information of the terminal device and / or information indicating the first RNA (for example, range information of the first RNA).

[0022] In combination with the first aspect, in some possible implementations, the first message includes the clock-related information and / or the duration information of the timer, and the duration information of the timer is used to indicate the duration of maintaining the terminal device that is interested in the clock-related information.

[0023] In combination with the first aspect, in some possible implementations, the clock-related information includes clock information and / or clock synchronization status information.

[0024] It should be understood that clock-related information can be used to achieve high-precision clock synchronization between the terminal device and the network device (the first network device or the second network device). The clock information in this application may indicate 5G clock information or 6G clock information, and the clock synchronization status information may refer to 5G clock synchronization status information or 6G clock synchronization status information, which is not limited in this application.

[0025] It should be understood that the clock synchronization status information may include one or more of the following: synchronization status, whether the time can be continuously traced back to the coordinated universal time (UTC), whether the time can be traced back to the global navigation satellite system (GNSS), clock frequency stability, clock accuracy, and clock source.

[0026] In combination with the first aspect, in some possible implementations, the method further includes: the first network device updates a terminal device managed by the first network device that is interested in clock-related information.

[0027] In combination with the first aspect, in some possible implementations, when the first network device determines that there is a terminal device managed by the first network device that is interested in clock-related information, the first network device sends the clock-related information.

[0028] It should be understood that the first network device determines that there is a terminal device managed by the first network device that is interested in clock-related information. The first network device can determine that the terminal device is a terminal device interested in clock-related information based on the context information of the terminal device. The terminal device is located within the coverage range of the first network device, that is, the terminal device belongs to the terminal devices managed by the first network device that are interested in clock-related information.

[0029] In combination with the first aspect, in some possible implementation methods, the RNA of the terminal device is updated, and the method also includes: the first network device sends a third message to the network device within the coverage range of the first RNA, and the third message is used to instruct the terminal device that is interested in the clock-related information to leave the first RNA.

[0030] It should be understood that the third message may include the first identification information of the terminal device and / or the range information of the first RNA.

[0031] It should also be understood that the coverage range in this application belongs to a network device within the first RNA, which may mean that the coverage range corresponding to the network device is entirely within the first RNA, or that the coverage range corresponding to the network device is partially within the first RNA.

[0032] It should also be understood that the third message is used to instruct the terminal device interested in clock-related information to leave the first RNA, which can be understood as: the third message is used to instruct the terminal device interested in clock-related information to leave the area corresponding to the first RNA; or the third message can be used to instruct the terminal device interested in the clock-related information to leave the coverage area of ​​a network device whose coverage range belongs to the first RNA. The certain network device may be a network device within the above-mentioned first RNA.

[0033] It should also be understood that the terminal device interested in clock-related information leaves the first RNA, which may mean that the RNA configured by the network device for the inactive terminal device interested in clock-related information does not include the first RNA, or the terminal device is no longer in the inactive state (for example, the terminal device changes from the inactive state to the connected state).

[0034] Based on the above technical solution, the RNA of the terminal device is updated. Assuming that the terminal device moves from the first RNA configured by the first network device to the second RNA, the first network device can send a third message to the network device whose coverage belongs to the first RNA, and the third message is used to instruct the terminal device to leave the first RNA. The first RNA and the second RNA may have the same area, or the first RNA and the second RNA may be completely different, which is not limited in this application. The terminal device updates its RNA, and the first network device sends the third message to the network device whose coverage belongs to the first RNA, so that the network device whose coverage belongs to the first RNA can perceive the departure of the terminal device, thereby being able to update the terminal device that is interested in clock-related information under its own management, so that the network device can send clock-related information on demand, thereby avoiding the situation where the terminal device updates its RNA, the network device does not perceive the departure of the terminal device, and continues to send clock-related information, resulting in a waste of resources and the introduction of unnecessary interference between network devices.

[0035] In combination with the first aspect, in some possible implementation methods, the RNA of the terminal device is updated, and the method also includes: the first network device sends a fourth message to the network device within the coverage range of the second RNA, and the fourth message is used to instruct the terminal device that is interested in the clock-related information to join the second RNA.

[0036] It should be understood that the fourth message may include the second identification information of the terminal device and / or the range information of the second RNA.

[0037] It should also be understood that the coverage range in this application belongs to a network device within the second RNA, which may mean that the coverage range corresponding to the network device is entirely within the second RNA, or that the coverage range corresponding to the network device is partially within the second RNA.

[0038] It should also be understood that the terminal device interested in clock-related information adds the first RNA, which may mean that the RNA configured by the network device for the inactive terminal device interested in clock-related information includes the second RNA.

[0039] It should also be understood that the fourth message is used to instruct a terminal device interested in clock-related information to join the second RNA. This can be understood as the fourth message being used to instruct the terminal device to send clock-related information within the coverage range of a certain network device, or to indicate that the coverage range corresponding to the certain network device overlaps with the second RNA. The certain network device may be a network device within the aforementioned second RNA.

[0040] Based on the above technical solution, when the RNA of a terminal device is updated, assuming that the terminal device moves from the first RNA configured by the first network device to the second RNA, the first network device can send a fourth message to the network device whose coverage falls within the second RNA, where the fourth message is used to instruct the terminal device to join the second RNA. After the terminal device updates its RNA, the first network device sends the fourth message to the network device whose coverage falls within the second RNA, thereby enabling the network device whose coverage falls within the second RNA to promptly learn that the terminal device, which is interested in clock-related information, has joined the second RNA, ensuring that the second network device sends clock-related information and that the relevant services / applications of the terminal device operate normally.

[0041] In combination with the first aspect, in some possible implementation methods, the RNA of the terminal device is updated, and the method also includes: the first network device sends a fifth message to the network device within the coverage range of the first RNA, and the fifth message is used to indicate that the information of the terminal device that is interested in the clock-related information has changed.

[0042] Based on the above technical solution, when the RNA of the terminal device is updated, the first network device can send a fifth message to the network device whose coverage belongs to the first RNA. The fifth message is used to indicate that the information of the terminal device has changed, so that the network device whose coverage belongs to the first RNA can update the relevant information of the inactive terminal devices under its management that are interested in clock-related information (for example, update of identification information, update of duration), thereby ensuring the normal operation of the relevant services / applications of the terminal device.

[0043] In combination with the first aspect, in some possible implementations, the fifth message includes first identification information of the terminal device.

[0044] In combination with the first aspect, in some possible implementations, the fifth message also includes one or more of the following: the second identification information of the terminal device, the range information of the first RNA, the clock-related information, and the duration information of the timer.

[0045] In combination with the first aspect, in some possible implementation methods, the method also includes: the first network device determines that the RNA of the terminal device is updated based on one or more of the following: the context information of the terminal device, the change of the terminal device from an inactive state to a connected state, and the small data transmission SDT process of the terminal device.

[0046] It should be understood that the first network device can determine that the RNA of the terminal device is updated based on one or more of the context information of the terminal device, the change of the terminal device from an inactive state to a connected state, and the SDT process of the terminal device.

[0047] It should also be understood that the RNA of the terminal device has been updated, and the triggering factor or reason for the update is related to one or more of the context information of the terminal device, the change of the terminal device from an inactive state to a connected state, and the SDT process of the terminal device.

[0048] In a second aspect, a communication method is provided. The method can be performed by a second network device. The second network device here can refer to the second network device itself or a processor, module, chip, or chip system that implements the method in the second network device, and this application does not limit this. The method includes:

[0049] The second network device receives a first message from the first network device, where the first message indicates that the terminal device is in an inactive state and sends clock-related information within the coverage range of the second network device; and the second network device sends the clock-related information within the coverage range of the second network device indicated by the first message based on the first message.

[0050] It should be understood that the coverage range of the second network device indicated by the first message may be one or more cells managed by the second network device.

[0051] According to the method provided in this application, the second network device receives the first message and, based on the first message, sends clock-related information to the coverage area of ​​the second network device indicated by the first message. This avoids the problem that when an inactive terminal device moves into the coverage area of ​​the second network device, the second network device is unable to perceive the terminal device and cannot provide the terminal device with clock-related information in a timely manner. This ensures that an inactive terminal device interested in clock-related information can still obtain clock-related information even if it moves out of the coverage area of ​​the serving network device, thereby ensuring the normal operation of the relevant applications / services of the terminal device.

[0052] In combination with the second aspect, in some possible implementations, the first message includes first identification information of the terminal device and coverage of the second network device.

[0053] Optionally, the first message may further include information indicating the first RNA.

[0054] In combination with the second aspect, in some possible implementations, the first message includes the clock-related information and / or the duration information of the timer, and the duration information of the timer is used to indicate the duration of maintaining the terminal device that is interested in the clock-related information.

[0055] In combination with the second aspect, in some possible implementations, the clock-related information includes clock information and / or clock synchronization status information.

[0056] In combination with the second aspect, in some possible implementations, the method further includes the second network device sending the clock-related information.

[0057] In conjunction with the second aspect, in some possible implementations, the method further includes:

[0058] The second network device updates the terminal device managed by the second network device and interested in the clock-related information according to the first message.

[0059] In combination with the second aspect, in some possible implementations, the RNA of the terminal device is updated, and the method also includes: the second network device receives a third message from the first network device, and the third message is used to instruct the terminal device interested in the clock-related information to leave the first RNA.

[0060] It should be understood that the third message may include the first identification information of the terminal device and / or information indicating the first RNA. Among them, the information indicating the first RNA in this application may be range information of the first RNA, or regional identification information of the first RNA, etc., which is not limited in this application.

[0061] It should also be understood that the terminal device interested in clock-related information leaves the first RNA, which may mean that the RNA configured by the network device (for example, the first network device, the second network device) for the inactive terminal device interested in clock-related information does not include the first RNA, or the terminal device is no longer in the inactive state (for example, the terminal device changes from the inactive state to the connected state).

[0062] Based on the above technical solution, the RNA of the terminal device is updated. Assuming that the terminal device moves from the first RNA configured by the first network device to the second RNA, the first network device can send a third message to the network device (such as the second network device) whose coverage belongs to the first RNA. Correspondingly, the second network device receives the third message from the first network device. The terminal device updates its RNA, and the second network device receives the third message from the first network device. The second network device determines that the inactive terminal device interested in clock-related information located in the first RNA has left the area based on the third message. The second network device can update the terminal devices interested in clock-related information that it manages in time, so as to avoid the second network device not sensing the departure of the terminal device and continuing to send clock-related information, resulting in a waste of resources and the introduction of unnecessary interference between network devices.

[0063] In combination with the second aspect, in some possible implementation methods, the RNA of the terminal device is updated, and the method also includes: the second network device receives a fourth message from the first network device, and the fourth message is used to instruct the terminal device that is interested in the clock-related information to join the second RNA.

[0064] It should be understood that the fourth message may include the second identification information of the terminal device and / or the range information of the second RNA.

[0065] It should also be understood that when the coverage range of the second network device belongs to both the first RNA and the second RNA, that is, the second network device receives the third message and the fourth message from the first network device, the third message and the fourth message can be carried in the same signaling and sent by the first network device to the second network device, or, the third message and the fourth message are respectively carried in different signalings and sent by the first network device to the second network device. This application does not limit this.

[0066] It should also be understood that the terminal device interested in clock-related information joins the first RNA, which may mean that the RNA configured for the inactive terminal device interested in clock-related information (for example, the first network device, the second network device) includes the second RNA.

[0067] Based on the above technical solution, when the RNA of the terminal device is updated, assuming that the terminal device moves from the first RNA configured by the first network device to the second RNA, the first network device can send a fourth message to the network device (e.g., the second network device) whose coverage belongs to the second RNA, and the fourth message is used to instruct the terminal device to join the second RNA. When the terminal device updates its RNA, the first network device sends the fourth message to the second network device, so that the network device whose coverage belongs to the second RNA can promptly be informed that the terminal device interested in clock-related information has joined the second RNA, thereby ensuring that the second network device sends clock-related information and ensuring the normal operation of the relevant services / applications of the terminal device.

[0068] In combination with the second aspect, in some possible implementation methods, the RNA of the terminal device is updated, and the method also includes: the second network device sends a third message to the network device within the coverage range of the first RNA, and the third message is used to instruct the terminal device that is interested in the clock-related information to leave the first RNA.

[0069] It should be understood that, assuming that the RNA of the terminal device is updated, the second network device is a new service network device providing services to the terminal device, and the second network device obtains the context of the terminal device, that is, the second network device can send third information to the network device within the coverage range of the first RNA to instruct the terminal device to leave the first RNA.

[0070] In combination with the second aspect, in some possible implementation methods, the RNA of the terminal device is updated, and the method also includes: the second network device sends a fourth message to the network device within the coverage range of the second RNA, and the fourth message is used to instruct the terminal device that is interested in the clock-related information to join the second RNA.

[0071] It should be understood that, assuming that the RNA of the terminal device is updated, the second network device is a new service network device providing services to the terminal device, and the second network device obtains the context of the terminal device, that is, the second network device can send fourth information to the network device within the coverage range of the second RNA, to instruct the terminal device to join the second RNA.

[0072] In combination with the second aspect, in some possible implementation methods, the RNA of the terminal device is updated, and the reason for the update is related to one or more of the following: the context information of the terminal device, the change of the terminal device from an inactive state to a connected state, and the small data transmission SDT process of the terminal device.

[0073] It should be understood that when the second network device sends a third message to a network device whose coverage range belongs to the first RNA, and / or the second network device sends a fourth message to a network device whose coverage range belongs to the second RNA, the second network device can determine that the RNA of the terminal device has been updated based on one or more of the following: the context information of the terminal device, the change of the terminal device from an inactive state to a connected state, and the small data transmission SDT process of the terminal device.

[0074] According to a third aspect, a communication device is provided, which includes: a processing unit for determining whether a terminal device is interested in clock-related information; and a transceiver unit for sending a first message to the second network device when the terminal device is in an inactive state, wherein the first message indicates that the clock-related information is sent to the terminal device within the coverage of the second network device.

[0075] The transceiver unit can perform the reception and transmission processing in the aforementioned first aspect, and the processing unit can also perform other processing operations except reception and transmission in the aforementioned first aspect.

[0076] In a fourth aspect, a communication device is provided, which includes: a transceiver unit for receiving a first message from a first network device, wherein the first message indicates that the clock-related information is sent to the terminal device within the coverage range of the second network device; and a transceiver unit for sending clock-related information to the coverage range of the second network device indicated by the first message.

[0077] The transceiver unit may perform the reception and transmission processing in the aforementioned second aspect.

[0078] In one possible implementation, the processing unit may also perform other processing operations in addition to receiving and sending in the aforementioned second aspect.

[0079] In a fifth aspect, the present application provides a communication device, comprising a processor configured to implement the method described in any one of the implementations of the first and second aspects above. The processor is coupled to a memory configured to store instructions and data. When the processor executes the instructions stored in the memory, the method described in any one of the implementations of the first and second aspects above can be implemented.

[0080] Optionally, the communication device may further include a memory. Optionally, the memory may be coupled to the processor. Optionally, the communication device may further include a communication interface, which is used for the device to communicate with other devices. Exemplarily, the communication interface may be a transceiver, hardware circuit, bus, module, pin, or other type of communication interface.

[0081] In one example, the communication device may be a network device, such as an access network device, or may be a device, module, or chip disposed in the network device, or may be a device that can be used in conjunction with the network device.

[0082] In another example, the communication device may be a terminal device, or may be a device, module, chip, etc. provided in the terminal device, or a device that can be used in conjunction with the terminal device.

[0083] In a sixth aspect, the present application provides a communication system, comprising at least one of a terminal device and a first network device. The terminal device is configured to execute the method provided in any one of the implementations of the first aspect, and the first network device is configured to execute the method provided in any one of the implementations described in the second aspect.

[0084] In the seventh aspect, the present application also provides a computer program, which, when executed on a computer, enables the computer to execute the method described in any one of the implementations of the first and second aspects above.

[0085] In an eighth aspect, the present application further provides a computer program product comprising instructions, which, when executed on a computer, enable the computer to execute the method described in any one of the implementations of the first and second aspects above.

[0086] In the ninth aspect, the present application also provides a computer-readable storage medium, which stores a computer program or instruction. When the computer program or instruction is run on a computer, the computer executes the method described in any implementation of the first and second aspects above.

[0087] In the tenth aspect, the present application also provides a chip, which is used to read the computer program stored in the memory and execute the method described in any implementation of the first aspect or the second aspect above; or, the chip includes a method for executing the method described in any implementation of the first aspect or the second aspect above.

[0088] In an eleventh aspect, the present application further provides a chip system, comprising a processor configured to support a device in implementing the method described in any of the implementations of the first and second aspects. In one possible design, the chip system further comprises a memory configured to store programs and data necessary for the device. The chip system may consist of a chip alone, or may include a chip and other discrete components.

[0089] In a twelfth aspect, a communication device is provided, the device being configured to execute the method provided in any one of the first to second aspects. Specifically, the device may include units and / or modules, such as a processing unit and / or a communication unit, for executing the method provided in any one of the above implementations of any one of the first to second aspects.

[0090] In one implementation, the apparatus is a communication device (e.g., a terminal device, or a first network device). When the apparatus is a communication device, the communication unit may be a transceiver or an input / output interface; and the processing unit may be at least one processor. Alternatively, the transceiver may be a transceiver circuit. Alternatively, the input / output interface may be an input / output circuit.

[0091] In another implementation, the apparatus is a chip, chip system, or circuit used in a communication device. When the apparatus is a chip, chip system, or circuit used in a device, the communication unit may be an input / output interface, interface circuit, output circuit, input circuit, pin, or related circuit on the chip, chip system, or circuit; and the processing unit may be at least one processor, processing circuit, or logic circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0092] FIG1 is a schematic diagram of a communication system 100 applicable to an embodiment of the present application.

[0093] FIG2 is a schematic diagram of an application architecture applicable to an embodiment of the present application.

[0094] FIG3 is a schematic diagram of a base station indicating 5G time to a terminal device via broadcasting.

[0095] FIG4 is a schematic diagram of a base station indicating 5G time to a terminal device via unicast.

[0096] FIG5 is a schematic diagram of a process for a terminal device to obtain 5G clock synchronization status information.

[0097] FIG6 is a schematic diagram of a scenario.

[0098] FIG7 is a schematic flowchart of a communication method provided in an embodiment of the present application.

[0099] FIG8 is a schematic flowchart of another communication method provided in an embodiment of the present application.

[0100] FIG9 is a schematic flowchart of another communication method provided in an embodiment of the present application.

[0101] FIG10 is a schematic flowchart of another communication method provided in an embodiment of the present application.

[0102] FIG11 is a schematic flowchart of another communication method provided in an embodiment of the present application.

[0103] FIG12 is a schematic structural diagram of a communication device 1200 provided in an embodiment of the present application.

[0104] FIG13 is a schematic structural diagram of a communication device 1300 provided in an embodiment of the present application. DETAILED DESCRIPTION

[0105] The technical solution in this application will be described below with reference to the accompanying drawings.

[0106] The technical solutions provided in this application can be applied to various communication systems, such as: fifth generation (5G) or new radio (NR) systems, long term evolution (LTE) systems, LTE frequency division duplex (FDD) systems, LTE time division duplex (TDD) systems, etc. The technical solutions provided in this application can also be applied to future communication systems, such as the sixth generation mobile communication system. The technical solutions provided in this application can also be applied to device to device (D2D) communication, vehicle-to-everything (V2X) communication, machine to machine (M2M) communication, machine type communication (MTC), and Internet of Things (IoT) communication systems or other communication systems. The following is an exemplary description taking the 5G system as an example.

[0107] FIG1 is a schematic diagram of an example of a communication system applicable to the present application. Communication system 100 may include at least one network device, such as network device 110 shown in FIG1 . Communication system 100 may also include at least one terminal device, such as terminal device 120 shown in FIG1 . Network device 110 and terminal device 120 may determine the propagation delay between them by mutually transmitting reference signals.

[0108] The technical solution provided in the present application can also be applied to sidelink (SL) communication scenarios. In this case, the network device 110 in FIG1 can also be replaced by another terminal device, as shown in FIG2 .

[0109] FIG2 is another schematic diagram of a communication system applicable to the present application. Communication system 200 may include at least two terminal devices, such as terminal device 210 and terminal device 220 shown in FIG2 . Terminal device 210 and terminal device 220 may determine the propagation delay between terminal device 210 and terminal device 220 by mutually transmitting reference signals.

[0110] To facilitate understanding of the embodiments of the present application, the technical solution of the present application is mainly introduced below by taking the communication system shown in FIG1 as an example.

[0111] The terminal device in the embodiments of the present application may 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, terminal, wireless communication device, user agent or user device.

[0112] The terminal device may be a device that provides voice / data to users, for example, a handheld device or vehicle-mounted device with a wireless connection function. At present, some examples of terminals are: mobile phones, tablet computers, laptop computers, PDAs, mobile internet devices (MIDs), wearable devices, virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, wireless terminals in self-driving, wireless terminals in remote medical surgery, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, cellular phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), handheld devices with wireless communication capabilities, computing devices or other processing devices connected to wireless modems, wearable devices, terminal devices in 5G networks or future evolved public land mobile communication networks (PLMNs). The terminal equipment in the network (PLMN), etc., is not limited to this in the embodiments of the present application.

[0113] As an example and not a limitation, in the embodiment of the present application, the terminal device may also be a wearable device. Wearable devices may also be called wearable smart devices, which are a general term for wearable devices that are intelligently designed and developed using wearable technology for daily wear, such as glasses, gloves, watches, clothing, and shoes. A wearable device is a portable device that is worn directly on the body or integrated into the user's clothes or accessories. Wearable devices are not only hardware devices, but also achieve powerful functions through software support, data interaction, and cloud interaction. Broadly speaking, wearable smart devices include those that are fully functional, large in size, and can achieve complete or partial functions without relying on smartphones, such as smart watches or smart glasses, as well as those that only focus on a certain type of application function and need to be used in conjunction with other devices such as smartphones, such as various smart bracelets and smart jewelry for vital sign monitoring.

[0114] In the embodiments of the present application, the device for implementing the function of the terminal device can be the terminal device, or it can be a device that can support the terminal device to implement the function, such as a chip system or chip, which can be installed in the terminal device. In the embodiments of the present application, the chip system can be composed of a chip, or it can include a chip and other discrete devices.

[0115] The network device in the embodiment of the present application can be a device for communicating with a terminal device. The network device can be a macro base station, a micro base station (also known as a small station), a satellite, a radio network controller (RNC), a node B (Node B, NB), a base station controller (BSC), a base transceiver station (BTS), a home base station (for example, a home evolved NodeB, or home Node B, HNB), a baseband unit (BBU), an access point (AP) in a wireless fidelity (WiFi) system, a wireless relay node, a wireless backhaul node, a transmission point (TP) or a transmission and reception point (TRP), etc. It can also be a gNB or transmission point (TRP or TP) in a 5G (such as NR) system, one or a group of antenna panels (including multiple antenna panels) of a base station in a 5G system, or a network node constituting a gNB or transmission point, such as a distributed unit (DU). Alternatively, the network device may be a relay station, an access point, a network device in a future 6G network, or a network device in a future evolved PLMN network, etc., and the present application embodiment does not limit this. The present application embodiment does not limit the specific technology and specific device form adopted by the network device.

[0116] In a network structure, the network device may include a centralized unit (CU) node, a distributed unit (DU) node, a radio access network (RAN) device including a CU node and a DU node, or a RAN device including a control plane CU node (CU-CP node) and a user plane CU node (CU-UP node) and a DU node.

[0117] The network equipment can provide services for the cell, and the terminal device can communicate with the cell through the transmission resources (for example, frequency domain resources, or spectrum resources) allocated by the network equipment. The cell can belong to a macro base station (for example, a macro eNB or a macro gNB, etc.) or a base station corresponding to a small cell. The small cells here may include: metro cells, micro cells, pico cells, femto cells, etc. These small cells have the characteristics of small coverage and low transmission power, and are suitable for providing high-speed data transmission services.

[0118] Network devices and terminal devices can be fixed or mobile. In the embodiments of the present application, network devices and terminal devices can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; they can also be deployed on water; and they can also be deployed in the air on aircraft, balloons, and satellites. The embodiments of the present application do not limit the scenarios in which network devices and terminal devices are located.

[0119] It should be understood that the specific forms of the terminal device and the network device in the embodiments of the present application are not particularly limited and are merely illustrative.

[0120] It should be understood that FIG1 and FIG2 are simplified schematic diagrams for ease of understanding only, and the communication system may also include other network devices and / or terminal devices, which are not shown in FIG1 and FIG2 .

[0121] To facilitate understanding of the embodiments of the present application, the following briefly describes the terms or technologies involved in the present application.

[0122] 1. 5G air interface time synchronization

[0123] In the Release 16 standard, 5G air interface time synchronization is achieved by the base station indicating a reference point of 5G time to the UE. The base station can provide 5G timing to the UE via broadcast (system information) or unicast (radio resource control (RRC) signaling).

[0124] The following description takes the broadcast mode as an example.

[0125] Figure 3 shows a schematic diagram of an example of a base station indicating 5G time to a UE via a broadcast method (system information SIB9). The SIB9 sent by the base station to the UE carries a specific 5G time T. The protocol defines the reference point of this time as the radio frame boundary where the system message window (SI window) containing SIB9 ends, or the radio frame boundary immediately following the end position. As shown in (1) in Figure 3, if the end position of the SI window where SIB9 is located happens to be the radio frame boundary with the radio frame system frame number (SFN) x, then the time indicated in SIB9 is the 5G time of the end position of the radio frame corresponding to SFN x; as shown in (2) in Figure 3, if the end position of the SI window where SIB9 is located falls in the middle of the radio frame of SFN x, then the time indicated in SIB9 is the 5G time of the end position of the radio frame corresponding to SFN x.

[0126] The following description takes unicast mode as an example.

[0127] Figure 4 shows a schematic diagram of a base station indicating 5G time via unicast. As shown in Figure 4, the base station sends a DLInformationTransfer message to the UE via unicast in a time slot with a radio frame system frame number (SFN) of x-3. The message includes a specific 5G time (denoted as time T) and the reference point SFN = x corresponding to the time. After receiving this unicast message, the UE can perform 5G time synchronization based on the 5G time T corresponding to the end position of the radio frame with SFN = x.

[0128] Since the signal sent by the base station will experience a certain propagation delay (for example, denoted as Tp) when it propagates through the air to reach the UE, when the UE performs 5G time synchronization based on the unicast message, after determining the 5G time T corresponding to the end position of the wireless frame of SFN=x, it is necessary to add Tp to the time T indicated by the base station to use it as the actual 5G synchronization time, that is, the UE needs to compensate for the propagation delay.

[0129] 2. Timing resilience system (TRS)

[0130] Based on the base station in the radio access network providing 5G clocks to the UE, the TRS feature is currently defined in relevant standards. When a UE accesses the 5G core network, the 5G core network can indicate to the base station which 5G clock synchronization states the UE is interested in. The base station then provides the UE with the corresponding 5G clock synchronization status information based on the UE's needs.

[0131] For example, the 5G clock synchronization status information includes one or more of the following:

[0132] 1) Synchronization status: locked, holdover, or free run;

[0133] Among them, locked indicates that the 5G clock is locked with the clock source, holdover indicates that the 5G clock is not locked with the clock source but is maintaining a certain clock accuracy, and free run indicates that the 5G clock is neither locked with the clock source nor maintaining clock accuracy.

[0134] 2) Whether it can be traced back to Coordinated Universal Time (UTC);

[0135] 3) Whether it can be traced back to the time of the global navigation satellite system (GNSS);

[0136] 4) Clock frequency stability;

[0137] 5) Clock accuracy;

[0138] 6) Clock source.

[0139] For a connected UE, the base station may directly provide the above clock synchronization status information to the UE via an RRC unicast message DLInformationTransfer.

[0140] For UEs in the Inactive / Idle state, the base station must first notify the UE that the 5G clock synchronization state has changed. After the UE enters the connected state, the base station provides the UE with the 5G clock synchronization state information through the DLInformationTransfer message.

[0141] Figure 5 shows a schematic diagram of the process of an Inactive / Idle state UE obtaining 5G clock synchronization status information. Specifically, when the base station side senses a change in the clock synchronization state, it carries a new Event ID in the SIB9 message; after the Inactive / Idle state UE reads the Event ID contained in the SIB9, if it finds that the Event ID has changed, or if the UE finds that the base station it is stationed in has changed, it can initiate an RRC connection establishment process or an RRC connection recovery process; when the base station finds that the UE has entered the connected state and the UE is interested in clock quality information, it sends 5G clock synchronization status information to the UE.

[0142] 3. Radio Access Network Notification Area Update (RAN Notification Area Update, RNA-U)

[0143] The base station switches the connected UE to the inactive state by sending an RRC Release message to the UE. The RRC Release message includes the suspendConfig information element, in which the base station configures the following information:

[0144] 1) Radio Access Network Notification Area (RAN notification area, RNA): The RNA area may include one or more cells within the coverage area of ​​a base station.

[0145] 2) Inactive-radio network temporary identifier (I-RNTI): an Inactive user identifier assigned by the base station to the UE.

[0146] 3) PeriodicRNAU-TimerValue: controls the timing length of timer t380 that initiates the periodic RNA-U process.

[0147] When the UE enters the Inactive state, timer t380 is started.

[0148] When an Inactive UE is moving, the UE initiates the RNA-U procedure under the following conditions:

[0149] 1) When timer t380 expires, the UE initiates the periodic RNA-U process.

[0150] 2) The UE reselects to a cell that does not belong to the configured RNA range, and the UE initiates the periodic RNA-U process.

[0151] When an Inactive UE initiates the RNA-U procedure, it must perform the RRC connection recovery procedure: the UE sends an RRCResumeRequest message carrying the UE's I-RNTI to the currently serving gNB (called the new serving gNB, or the new gNB). The new gNB identifies the UE's serving gNB (called the last serving gNB, or the anchor gNB) based on the UE's I-RNTI. This serving gNB is the one that released the UE into the Inactive state. If the new gNB and the last serving gNB are different, the new serving gNB initiates the RETRIEVE UE CONTEXT procedure to the last serving gNB to request the UE context. The last serving gNB decides whether to perform anchor relocation, meaning the last serving gNB determines whether to migrate the UE's context to the new gNB, which then maintains the Inactive UE. If the last serving gNB determines not to migrate the UE context, it can send an RRCRelease message to the UE to transfer the UE to the Inactive state or the Idle state. If the last serving gNB determines to transfer the UE context to the new gNB, the new gNB can decide to transfer the UE to the Connected state, keep it in the Inactive state, or transfer it to the Idle state after obtaining the UE context.

[0152] It should be understood that in the cells where the RNA area configured by the Inactive UE contains multiple base stations, only the last serving gNB of the UE can perceive whether the UE is interested in clock-related information, and other base stations in the RNA cannot perceive whether the UE is interested in clock information and / or clock state synchronization information.

[0153] Figure 6 shows a scenario diagram. When gNB1 transitions a UE to the Inactive state, gNB1 is considered the last serving gNB for the UE. If the UE is interested in clock information, gNB1 can broadcast SIB9 to provide the UE with clock information or indicate whether the clock quality has changed through SIB9. If the Inactive UE moves and leaves the coverage of the last serving gNB and moves to the coverage of a new base station (e.g., gNB2), gNB2 will not be able to detect the presence of an interested Inactive UE within its coverage area, i.e., gNB2 may not broadcast SIB9. In this case, the UE may not receive clock information or perceive whether the clock quality has changed, which may cause the UE's related applications to not work properly due to the loss of clock information.

[0154] The current solution to this problem is for all base stations to broadcast SIB9 to provide clock information. However, since a base station may not have UEs interested in clock information within its coverage area, the base station will still broadcast SIB9, resulting in unnecessary resource waste and introducing unnecessary inter-station interference.

[0155] In view of the above problems, the present application provides a communication method and a communication device. The method enables an inactive terminal device interested in clock-related information to obtain clock-related information, thereby ensuring the normal operation of applications / services related to the terminal device.

[0156] FIG7 is a flow chart of a synchronization method provided in an embodiment of the present application.

[0157] It should be understood that in the embodiments of the present application, the first network device can be understood as the last serving gNB of the terminal device, and the second network device can be understood as the new gNB of the terminal device. As shown in Figure 7, the method may include the following steps:

[0158] 701. A first network device determines that a terminal device is interested in clock-related information.

[0159] Among them, the terminal device is interested in clock-related information, which can be understood as the normal operation or normal work of the relevant applications or services of the terminal device requires clock-related information, or the terminal device has a demand for clock-related information, or the terminal device needs to obtain clock-related information.

[0160] It should be understood that the first network device may determine that the terminal device is a terminal device interested in clock-related information in the following ways:

[0161] 1) The 5G core network node (eg, a session management function (SMF)) indicates to the first network device that the terminal device is a terminal device that is interested in clock-related information.

[0162] For example, when a terminal device in an idle state accesses a first network device and enters a connected state, the SMF indicates to the first network device that the terminal device is interested in clock-related information.

[0163] 2) The third network device sends first indication information to the first network device, where the first indication information is used to indicate that the terminal device is interested in clock-related information. Correspondingly, the first network device receives the first indication information from the third network device.

[0164] The third network device is a network device that provides services to the terminal device before the terminal device accesses the first network device.

[0165] For example, in the process of the terminal device switching from the third network device to the first network device, the third network device sends a first indication message to the first network device. Accordingly, the first network device receives the first indication message from the third network device. The first indication message is used to indicate that the terminal device is a terminal device interested in clock-related information.

[0166] 3) The terminal device sends second indication information to the first network device, where the second indication information is used to indicate that the terminal device is interested in clock-related information. Correspondingly, the first network device receives the second indication information from the terminal device.

[0167] For example, when the terminal device is in a connected state while accessing the first network device, the terminal device may send second indication information to the first network device, where the second indication information is used to indicate that the terminal device is interested in clock-related information.

[0168] Among them, the second indication information can be carried in the RRC message exchanged between the terminal device and the first network device, which is not limited in this application.

[0169] It should be understood that when the terminal device is in a connected state, the first network device can send clock-related information to the terminal device in the unicast manner shown in FIG. 4 .

[0170] It should also be understood that the first network device can determine that the terminal device is a terminal device interested in clock-related information through any one or more of the above methods 1), 2), and 3). In the above methods 1), 2), and 3), in the process of indicating to the first network device that the terminal device is a terminal device interested in clock-related information, the specific content of the clock-related information that the terminal device is interested in can also be indicated to the first network device.

[0171] In a possible implementation manner, the clock-related information includes clock information and / or clock synchronization status information.

[0172] It should be understood that the clock information in the embodiments of the present application can be used to indicate 5G clock information and / or sixth generation (6G) communication system clock information, and the clock synchronization status information can be used to indicate 5G clock synchronization status information and / or 6G clock synchronization status information, and this application does not limit this. The specific contents of the clock information and clock synchronization status information in this application are similar to the specific contents of the clock information and clock synchronization status information described above, and will not be introduced one by one here.

[0173] 702. The first network device sends a first message to the second network device.

[0174] Accordingly, the second network device receives the first message from the first network device.

[0175] It should be understood that the first message instructs the terminal device to send clock-related information within the coverage of the second network device. The present application does not limit whether the terminal device is within the coverage of the second network device.

[0176] In a possible implementation manner, the first message may include first identification information of the terminal device and / or coverage information of the second network device.

[0177] In another possible implementation, the first message may include the first identification information of the terminal device and / or information indicating the first RNA. For example, the information indicating the first RNA may be range information of the first RNA.

[0178] Among them, the first RNA includes the coverage range of the second network device, that is, part or all of the coverage area corresponding to the second network device belongs to the first RNA configured by the first network device for the terminal device, or the first RNA includes one or more cells managed by the second network device.

[0179] It should be understood that the first identification information of the terminal device may be an inactive-radio network temporary identifier (I-RNTI) configured by the first network device for the terminal device, and the I-RNTI may be a full I-RNTI or a short I-RNTI, or the first identification information may be an identifier (ID) of the terminal device.

[0180] It should also be understood that the coverage information of the second network device may be the coverage of the second network device included in the first RNA configured by the first network device for the terminal device, or the overlapping part of the entire coverage corresponding to the first RNA and the second network device.

[0181] It should also be understood that the range information of the first RNA can be: the coverage range of the second network device within the first RNA corresponds to the cell within the first RNA. The range information of the first RNA can be identification information of one or more cells, or area identification information of one or more RNAs.

[0182] In a possible implementation, the first message may also include clock-related information and / or timer duration information that the terminal device is interested in.

[0183] The clock-related information that the terminal device is interested in may be detailed content of the clock-related information that the terminal device is actually interested in, or one or more items of the clock-related information that the terminal device is interested in.

[0184] The duration information of the timer is used to indicate the duration of maintaining the terminal device that is interested in clock-related information.

[0185] It should be understood that maintaining a terminal device that is interested in clock-related information can be understood as the second network device treating the terminal device as a terminal device that is managed by itself and is interested in clock-related information, and sending clock-related information within the coverage range determined by the first message associated with the terminal device.

[0186] For example, the duration information of the timer may indicate the maintenance / management duration corresponding to a terminal device in an inactive state that is managed by the second network device and is interested in clock-related information.

[0187] According to the method shown in FIG7 , the method may further include step 703:

[0188] 703 : The second network device updates the inactive terminal devices managed by the second network device and interested in clock-related information according to the first message.

[0189] For example, after the second network device receives the first message from the first network device, the second network device updates the inactive terminal devices managed by the second network device and interested in clock-related information according to the first message.

[0190] As an example, assuming that the terminal device is an inactive terminal device managed by the second network device and interested in clock-related information, the second network device restarts the maintenance time corresponding to the terminal device according to the first message.

[0191] As another example, assuming that the terminal device is not among the inactive terminal devices managed by the second network device that are interested in clock-related information, the second network device adds the terminal device to the inactive terminal devices managed by the second network device that are interested in clock-related information based on the first message, and starts the maintenance time corresponding to the terminal device.

[0192] It should be understood that among the inactive terminal devices that are interested in clock-related information and managed by the second network device, each terminal device can correspond to a timer (such as a validity timer), and the timing duration of the timer is the above-mentioned maintenance duration. When the second network device adds the terminal device to the inactive terminal devices that are interested in clock-related information and managed by the second network device according to the first message, it starts the timer corresponding to the terminal device. When the timer corresponding to the terminal device times out, the second network device deletes the terminal device from the inactive terminal devices that are interested in clock-related information that it manages; when the timer corresponding to the terminal device does not time out, the second network device receives the first message, and the first message is used to indicate that the terminal device is interested in clock-related information within the first RNA, and the second network device will restart the timer corresponding to the terminal device in the inactive terminal devices that are interested in clock-related information that it manages.

[0193] It should also be understood that the duration information of the timer may be predefined by the protocol, or determined by the first network device and carried in the first message (for example, the effective duration RNAU-timer value of the periodic radio access network notification area update configured by the first network device for the terminal device), or the duration information of the timer is not carried in the first message and is determined by the second network device. This application does not limit this.

[0194] In one possible implementation, the second network device updates, based on the first message, inactive terminal devices managed by the second network device that are interested in clock-related information. The second network device may manage inactive terminal devices that are interested in clock-related information at a cell granularity.

[0195] For example, the coverage range corresponding to the second network device corresponds to multiple cells, and the cells within the coverage range of the first RNA corresponding to the second network device are cell #1 and cell #2, that is, the second network device updates the list of inactive terminal devices corresponding to cell #1 and cell #2 that are interested in clock-related information based on the first message.

[0196] It should be understood that step 703 is an internal implementation operation of the second network device and is an optional step.

[0197] 704. The second network device sends clock-related information.

[0198] For example, the second network device sends clock-related information to the coverage range of the second network device indicated in the first message according to the first message.

[0199] When the first message includes information indicating the coverage of the second network device, the second network device may determine to send clock-related information within the coverage of the second network device indicated by the first message based on the information indicating the coverage of the second network device in the first message.

[0200] When the first message includes information indicating the first RNA, the second network device can learn from the information indicating the first RNA that the area it manages overlaps with the first RNA, further determine the area to send clock-related information, and send the clock-related information.

[0201] It should be understood that the second network device sending the clock-related information can be understood as the second network device performing clock synchronization on the inactive terminal devices within the coverage area that are interested in the clock-related information.

[0202] It should also be understood that the clock-related information may be carried in a SIB9 message of the second network device and sent, or the clock-related information may be sent through separate signaling, which is not limited in this application.

[0203] It should also be understood that step 704 is an optional step. In the specific execution process, step 704 is decoupled from step 702, that is, the present application does not limit the second network device to executing step 704 to send clock-related information after receiving the first message according to step 702.

[0204] In one possible implementation, in combination with the above-mentioned step 703, the second network device can update the inactive terminal devices managed by the second network device and interested in clock-related information based on the first message, that is, the inactive terminal devices managed by the second network device and interested in clock-related information include the terminal device, and the second network device sends clock-related information.

[0205] It should be understood that the above steps 703 and 704 use the second network device as an example, where the network device updates the inactive terminal devices it manages that are interested in clock-related information and transmits the clock-related information. Of course, the first network device can also update the inactive terminal devices it manages that are interested in clock-related information and determine whether to transmit the clock-related information based on whether the first network device manages any inactive terminal devices that are interested in clock-related information. The detailed process is similar to that of the second network device in steps 703 and 704 above and will not be repeated here.

[0206] Among them, when the first network device updates the inactive terminal device that is managed by the first network device and is interested in clock-related information, it is not necessary to execute after step 702, that is, after the first network device instructs the terminal device to enter the inactive state from the connected state, the first network device can perform relevant operations to update the inactive terminal device that is managed by the first network device and is interested in clock-related information.

[0207] According to the method shown in FIG7 above, the first network device determines that the terminal device is a terminal device that is interested in clock-related information. When the terminal device is in an inactive state, the first network device sends a first message to a network device (such as a second network device) whose coverage range belongs to the first RNA. The first message indicates that clock-related information is sent for the terminal device within the coverage range of the second network device. When the terminal device that is interested in clock-related information is in an inactive state, the first message instructs the second network device to send clock-related information, thereby avoiding the second network device from being unable to perceive that the terminal device is a terminal device that is interested in clock-related information, and ensuring that the inactive terminal device that is interested in clock-related information can still obtain clock-related information even if it moves to the coverage range of other network devices, so as to enable the normal operation of related applications / services.

[0208] At the same time, network devices (such as the first network device and the second network device) can send clock-related information on demand based on the inactive terminal devices they manage that are interested in clock-related information, thereby avoiding the waste of resources and the introduction of unnecessary interference caused by long-term broadcasting of clock-related information by network devices, thereby saving resource overhead.

[0209] Based on the method shown in FIG. 7 , before step 702 , the method may further include the following steps:

[0210] 705. The first network device sends a second message to the terminal device.

[0211] Correspondingly, the terminal device receives the second message from the first network device.

[0212] The second message indicates that the terminal device enters an inactive state from a connected state. The second message includes information indicating a first RNA, and the first RNA includes a coverage range of the second network device.

[0213] It should be understood that the first RNA is configured by the first network device for the terminal device.

[0214] It should be understood that the first RNA may include all or part of the coverage / management area corresponding to one or more network devices. The embodiment of the present application is introduced by taking the second network device as an example, and does not have any limiting effect on the method in the present application.

[0215] It should also be understood that the second message can be carried in a release message (RRC release) sent by the first network device to the terminal device, to instruct the terminal device to enter an inactive state from a connected state.

[0216] It should also be understood that when the first network device sends the second information to the terminal device and the terminal device enters the inactive state from the connected state, the first network device executes step 702 in FIG. 7 .

[0217] When the first network device updates an inactive terminal device that is managed by the first network device and is interested in clock-related information, after the first network device instructs the terminal device to enter an inactive state from a connected state, the first network device may perform operations similar to those in steps 703 and 704. For example, the first network device updates an inactive terminal device that is managed by the first network device and is interested in clock-related information; when the first network device determines that it manages an inactive terminal device that is interested in clock-related information, the first network device sends the clock-related information.

[0218] Next, the communication method provided in the embodiments of the present application will be exemplarily introduced in combination with different scenarios.

[0219] Scene 1

[0220] During the RNA-U process of the terminal device, the first network device configures a new RNA (for example, a second RNA) for the terminal device. The following will exemplarily introduce a communication method provided in an embodiment of the present application in conjunction with Figures 8 and 9.

[0221] FIG8 is a schematic flowchart of another communication method provided in an embodiment of the present application.

[0222] It should be understood that in the process of initiating RNA-U in the old RNA (for example, the first RNA) configured by the first network device by an inactive terminal device interested in clock-related information, the method shown in Figure 8 is exemplarily introduced by taking the first network device as gNB1 as an example, the second network device as gNB2 as an example, the network devices within the coverage range of the first RNA as gNB1 and gNB2 as an example, and the network devices within the coverage range of the second RNA as gNB1, gNB2 and gNB3 as an example.

[0223] As shown in FIG8 , the method may include the following steps:

[0224] 801. The terminal device sends an RRC connection recovery request message to gNB2. In response, gNB2 receives the RRC connection recovery request message from the terminal device.

[0225] It should be understood that during the RNA-U process, the inactive terminal device sends an RRC connection restoration request message to gNB2. The RRC connection restoration request message is used by the terminal device to request access to gNB2.

[0226] 802. gNB2 sends a first request message to gNB1. Correspondingly, gNB1 receives the first request message from gNB2.

[0227] Among them, the first request information is used to request context information of the terminal device from gNB1.

[0228] It should be understood that in the embodiments of the present application, unless otherwise specified, the context information of the terminal device can be understood as the complete context information of the terminal device.

[0229] 803. gNB1 determines not to migrate the context information of the terminal device to gNB2.

[0230] For example, after receiving the first request, gNB1 determines not to migrate the context information of the terminal device to gNB2. It is understandable that gNB1 determines that gNB1 will continue to maintain the terminal device.

[0231] It should be understood that step 803 is an internal implementation process of gNB1, that is, step 803 may not be reflected in the operation process.

[0232] 804. gNB1 sends a retrieval of terminal device context failure message to gNB2. In response, gNB2 receives the retrieval of terminal device context failure message from gNB1.

[0233] It should be understood that the UE context retrieval failure message (e.g., the Retrieve UE Context Failure message) includes a second message. The second message includes a second RNA configured by gNB1 for the UE and / or second identification information configured by gNB1 for the UE. For example, the second RNA and / or second identification information are determined by gNB1 based on the UE's RNA-U.

[0234] It should be understood that the second message can be carried in the UE context retrieval failure information and sent by gNB1 to gNB2, or the second message can be sent by gNB1 to gNB2 through other signaling (such as RRC Release message) or through separate signaling.

[0235] 805. gNB2 sends a second message to the terminal device. Accordingly, the terminal device receives the second message from gNB2.

[0236] For example, after gNB2 receives a message indicating a failure to retrieve a terminal device context from gNB1, gNB2 forwards a second message in the message indicating a failure to retrieve a terminal device context to the terminal device. The second message indicates that the terminal device remains in an inactive state. The second message includes information indicating the first RNA.

[0237] It should be understood that gNB1 determines not to migrate the context of the terminal device to gNB2, and gNB1 configures the second RNA and / or second identification information for the terminal device. gNB1 further notifies network devices within the coverage of the first RNA / second RNA to update inactive terminal devices under their management that are interested in clock-related information. As shown in FIG8 , the network devices within the coverage of the first RNA / second RNA may be instructed to update inactive terminal devices under their management that are interested in clock-related information in the following manner:

[0238] Method 1

[0239] 806. gNB1 sends a third message to the network device within the coverage range of the first RNA.

[0240] Accordingly, the network device within the coverage of the first RNA receives the third message from gNB1.

[0241] For example, gNB1 sends the third message to gNB2.

[0242] The third message is used to instruct the terminal device that is interested in the clock-related information to leave the first RNA.

[0243] It should be understood that the third message is used to instruct the terminal device interested in clock-related information to leave the first RNA, which can be understood as: the third message is used to instruct the terminal device interested in clock-related information to leave the area corresponding to the first RNA; or the third message can be used to instruct the terminal device interested in the clock-related information to leave the coverage area of ​​a certain network device whose coverage range belongs to the first RNA. The certain network device can be a network device within the above-mentioned first RNA.

[0244] It should be understood that the third message includes the first identification information of the terminal device. Optionally, the third message may also include range information of the first RNA.

[0245] It should be understood that gNB1 sends a third message to a network device within the coverage of a first RNA configured by gNB1 for a terminal device, indicating that the inactive terminal device interested in clock-related information has left the coverage of the network device. Accordingly, the network device within the coverage of the first RNA removes the terminal device from its managed list of inactive terminal devices interested in clock-related information based on the third message.

[0246] 807. gNB1 sends a fourth message to the network device within the coverage range of the second RNA.

[0247] Accordingly, the network device within the coverage of the second RNA receives the fourth message from gNB1.

[0248] For example, gNB1 sends the fourth message to gNB2 and gNB3.

[0249] The fourth message is used to instruct an inactive terminal device that is interested in clock-related information to join the second RNA.

[0250] It should be understood that the fourth message is used to instruct a terminal device interested in clock-related information to join the second RNA. It can be understood that the fourth message is used to instruct the terminal device to send clock-related information within the coverage range of a certain network device, or to indicate that the coverage range corresponding to the certain network device overlaps with the second RNA. The certain network device may be a network device within the above-mentioned second RNA.

[0251] It should be understood that the fourth message includes the second identification information of the terminal device and the coverage of the second RNA. Optionally, the fourth message may also include the specific content of the clock-related information that the terminal device is interested in and the duration information of the timer.

[0252] It should be understood that gNB1 sends a fourth message to a network device within the coverage of the second RNA configured by gNB1 for the terminal device. This fourth message indicates that the inactive terminal device interested in clock-related information has joined the coverage of the network device. Accordingly, the network device adds the terminal device to its managed inactive terminal devices interested in clock-related information based on the fourth message.

[0253] It should be understood that when the coverage area of ​​a network device (e.g., gNB2) falls within the range of both the first RNA and the second RNA, gNB2 can receive both the third message from gNB1 and the fourth message from gNB1. The third message and the fourth message can be carried in the same message and sent to gNB2. Accordingly, gNB2 can delete the terminal device from the list of inactive terminal devices under its management that are interested in clock-related information based on the third message, and add the terminal device to the list of inactive terminal devices under its management that are interested in clock-related information based on the fourth message.

[0254] Method 2

[0255] 808. gNB1 sends a fifth message to the network device whose coverage range belongs to the first RNA.

[0256] Accordingly, the network device whose coverage range belongs to the range of the first RNA receives the fifth message from gNB1.

[0257] For example, gNB1 sends the fifth message to gNB2, and accordingly, gNB2 receives the fifth message from gNB1.

[0258] The fifth message is used to indicate that information of a terminal device that is interested in clock-related information has changed, and the fifth message includes first identification information of the terminal device.

[0259] It should be understood that after the network device whose coverage range belongs to the first RNA receives the fifth message, it restarts the timer corresponding to the inactive terminal device in the terminal device managed by itself that is interested in clock-related information based on the first identification information of the terminal device in the fifth message.

[0260] Optionally, the fifth message may also include the second identification information of the terminal device, the range information of the first RNA, the clock-related information that the terminal device is interested in, and the duration information of the timer.

[0261] It should be understood that after the network device whose coverage range falls within the range of the first RNA receives the fifth message, the network device replaces the first identification information of the terminal device with the second identification information and updates the valid duration corresponding to the terminal device according to the duration information of the timer. The network device may also update the specific content of the clock-related information corresponding to the terminal device according to the clock-related information of interest to the terminal device in the fifth message.

[0262] It should be understood that the steps in the above-mentioned method 1 and method 2 can be performed after step 803 or after step 804, and this application does not limit this.

[0263] 809. gNB1, gNB2, and gNB3 update the inactive terminal devices that are interested in clock-related information under their respective management.

[0264] After step 803, gNB1 may execute step 809. gNB2 and gNB3 each execute step 809 upon receiving one or more of the third message, the fourth message, and the fifth message from gNB1.

[0265] It should be understood that step 809 is an optional step. Step 809 is similar to step 703 in FIG. 7 . For details, please refer to the detailed description of step 703 above, which will not be repeated here.

[0266] 810. gNB1, gNB2, and gNB3 send clock-related information as needed.

[0267] For example, when one or more of gNB1, gNB2 and gNB3 determine that there is a terminal device among the inactive terminal devices that they manage and are interested in clock-related information, the network device that determines that there is a terminal device among the inactive terminal devices that they manage and are interested in clock-related information sends clock-related information.

[0268] It should be understood that step 810 is similar to step 704 in FIG. 7 . For details, please refer to the detailed description in step 704 , which will not be repeated here.

[0269] It should be understood that steps 809 and 810 are both optional. Step 809 is an internal implementation of gNB1, gNB2, and gNB3 and is optional during specific operations. Step 810 is performed when gNB1, gNB2, and gNB3 each manage an inactive terminal device that is interested in clock-related information. Step 810 is not required when gNB1, gNB2, and gNB3 each manage no inactive terminal device that is interested in clock-related information. Step 810 is decoupled from any of steps 801 through 809.

[0270] According to the method shown in Figure 8 above, when the terminal device is performing RNA-U in the first RNA, the first network device sends a third message to the network device within the coverage range of the first RNA to instruct the terminal device to leave the first RNA, that is, the network device within the coverage range of the first RNA moves the terminal device out of the inactive terminal devices managed by itself that are interested in clock-related information; the first network device sends a fourth message to the network device within the coverage range of the second RNA to instruct the terminal device to join the second RNA, that is, the network device within the coverage range of the second RNA adds the terminal device to the inactive terminal devices managed by itself that are interested in clock-related information, to ensure that the inactive terminal device can still enable the network device to perceive the terminal device in time during the RNA-U process, and provide clock-related information to the terminal device, thereby ensuring the normal operation of related services / data.

[0271] At the same time, network devices (such as gNB1, gNB2 and gNB3) can send clock-related information on demand based on the inactive terminal devices they manage that are interested in clock-related information, thereby avoiding the network devices sending unnecessary clock-related information, which would lead to resource waste and introduce inter-station interference, saving resource overhead.

[0272] FIG9 is a schematic flowchart of another communication method provided in an embodiment of the present application.

[0273] It should be understood that in the process of initiating RNA-U in the old RNA (for example, the first RNA) configured by the first network device by an inactive terminal device interested in clock-related information, the method shown in Figure 9 is exemplarily introduced by taking the first network device as gNB1 as an example, the second network device as gNB2 as an example, the network devices within the coverage range of the first RNA as gNB1 and gNB2 as an example, and the network devices within the coverage range of the second RNA as gNB1, gNB2 and gNB3 as an example.

[0274] As shown in FIG9 , the method may include the following steps:

[0275] 901. The terminal device sends an RRC connection recovery request message to gNB2. In response, gNB2 receives the RRC connection recovery request message from the terminal device.

[0276] It should be understood that during the RNA-U process, the inactive terminal device sends an RRC connection restoration request message to gNB2. The RRC connection restoration request message is used by the terminal device to request access to gNB2.

[0277] 902. gNB2 sends a first request message to gNB1. Correspondingly, gNB1 receives the first request message from gNB2.

[0278] Among them, the first request information is used to request context information of the terminal device from gNB1.

[0279] 903. gNB1 determines to migrate the context information of the terminal device to gNB2.

[0280] For example, after receiving the first request, gNB1 determines to migrate the context information of the terminal device to gNB2. It is understandable that gNB1 determines that gNB2 will maintain the terminal device.

[0281] It should be understood that step 903 is an internal implementation process of gNB1, that is, step 903 may not be reflected in the operation process.

[0282] 904. gNB1 sends a retrieval terminal device context feedback message to gNB2. In response, gNB2 receives the retrieval terminal device context feedback message from gNB1.

[0283] It should be understood that the retrieve terminal device context feedback message (eg, Retrieve UE Context Response message) includes context information of the terminal device.

[0284] It should also be understood that the retrieval terminal device context feedback message may include information indicating the first RNA (eg, range information of the first RNA).

[0285] 905. gNB2 sends a second message to the terminal device. Accordingly, the terminal device receives the second message from gNB2.

[0286] For example, after gNB2 receives the retrieve UE context feedback message from gNB1, gNB2 determines a second message and sends the second message to the terminal device. The second message instructs the terminal device to remain in an inactive state.

[0287] It should be understood that gNB1 determines to migrate the context information of a terminal device to gNB2. gNB2 configures the terminal device with a second RNA and / or second identification information. gNB1 / gNB2 needs to notify network devices within the coverage area of ​​the first RNA / second RNA to update the inactive terminal devices under their management that are interested in clock-related information. As shown in FIG9 , the network devices within the coverage area of ​​the first RNA / second RNA can be instructed to update the inactive terminal devices under their management that are interested in clock-related information in the following manner:

[0288] Method 3

[0289] 906. gNB1 sends a third message to the network device within the coverage range of the first RNA.

[0290] Accordingly, the network device within the coverage of the first RNA receives the third message from gNB1.

[0291] For example, gNB1 sends the third message to gNB2.

[0292] It should be understood that since gNB1 migrates the context information of the terminal device to gNB2, the gNB2 knows the first RNA, the second RNA, the first identification information, and one or more of the second identification information corresponding to the terminal device, and the gNB1 sends a third message to the network devices within the coverage range of the first RNA, wherein the gNB1 sends the third message to the network devices other than gNB2 within the coverage range of the first RNA.

[0293] 907. gNB2 sends a fourth message to the network device within the coverage range of the second RNA.

[0294] Accordingly, the network device whose coverage range belongs to the second RNA receives the fourth message from gNB2.

[0295] For example, gNB2 sends the fourth message to gNB3 and gNB1.

[0296] It should be understood that the specific content and function of the fourth message are similar to those of step 807 in FIG. 8 , and will not be described in detail here.

[0297] It should also be understood that the above steps 906 and 907 are similar to steps 806 and 807 in FIG. 8 . Please refer to the description in FIG. 8 for details, which will not be repeated here.

[0298] Method 4

[0299] 908. gNB2 sends a fifth message to the network device whose coverage range belongs to the first RNA.

[0300] Accordingly, the network device whose coverage range belongs to the range of the first RNA receives the fifth message from gNB2.

[0301] Among them, gNB2 receives a retrieved UE context feedback message from gNB1, and the retrieved UE context feedback message includes information indicating the first RNA (for example, range information of the first RNA). The gNB2 determines the range of the first RNA based on the information indicating the first RNA, and sends a fifth message to the network device whose coverage range belongs to the range of the first RNA.

[0302] It should be understood that the specific content and detailed functions of the fifth message are similar to those of step 808 in FIG. 8 . For details, please refer to the detailed introduction in FIG. 8 .

[0303] 909. gNB1, gNB2, and gNB3 update the inactive terminal devices that are interested in clock-related information under their respective management.

[0304] After step 903, gNB1 may execute step 909. gNB2 and gNB3 each execute step 909 upon receiving one or more of the third message, the fourth message, and the fifth message from gNB1.

[0305] It should be understood that step 909 is similar to step 703 in FIG. 7 . For details, please refer to the detailed introduction in step 703 , which will not be repeated here.

[0306] 910. gNB1, gNB2, and gNB3 send clock-related information as needed.

[0307] For example, when one or more of gNB1, gNB2 and gNB3 determine that there is a terminal device among the inactive terminal devices that they manage and are interested in clock-related information, the network device that determines that there is a terminal device among the inactive terminal devices that they manage and are interested in clock-related information sends clock-related information.

[0308] It should be understood that step 910 is similar to step 810 in FIG. 8 . For details, please refer to the detailed introduction in step 810 , which will not be repeated here.

[0309] According to the method shown in Figure 9 above, when the terminal device performs RNA-U, the first network device sends a third message to the network device within the coverage range of the first RNA to instruct the terminal device to leave the first RNA, that is, the network device within the coverage range of the first RNA deletes the terminal device from the inactive terminal devices managed by itself that are interested in clock-related information; the second network device sends a fourth message to the network device within the coverage range of the second RNA to instruct the terminal device to join the second RNA, that is, the network device within the coverage range of the second RNA adds the terminal device to the inactive terminal devices managed by itself that are interested in clock-related information, to ensure that when the inactive terminal device moves to the coverage range of the network device within the second RNA, the network device can perceive the terminal device in time and provide clock-related information to the terminal device, to ensure the relevant application / service needs of the inactive terminal device, and to improve user experience.

[0310] At the same time, network devices (such as gNB1, gNB2 and gNB3) can send clock-related information on demand based on the inactive terminal devices they manage that are interested in clock-related information, thereby avoiding the network devices sending unnecessary clock-related information, which would lead to resource waste and introduce inter-station interference, saving resource overhead.

[0311] Scene 2

[0312] During the RNA-U process, the terminal device changes from an inactive state to a connected state. The first network device / the second network device instructs the network device within the coverage range of the first RNA to delete the inactive terminal device managed by itself that is interested in clock-related information. The following will exemplarily introduce a communication method provided in an embodiment of the present application in conjunction with Figure 10.

[0313] FIG10 is a schematic flowchart of another communication method provided in an embodiment of the present application.

[0314] It should be understood that in the process of initiating RNA-U in the old RNA (for example, the first RNA) configured by the first network device by an inactive terminal device interested in clock-related information, the method shown in Figure 10 is exemplarily introduced by taking the first network device as gNB1 as an example, the second network device as gNB2 as an example, the network devices within the coverage range of the first RNA as gNB1 and gNB2 as an example, and the network devices within the coverage range of the second RNA as gNB1, gNB2 and gNB3 as an example.

[0315] 1001. The terminal device sends an RRC connection restoration request message to gNB2. In response, gNB2 receives the RRC connection restoration request message from the terminal device.

[0316] It should be understood that during the RNA-U process, the inactive terminal device sends an RRC connection restoration request message to gNB2. The RRC connection restoration request message is used by the terminal device to request access to gNB2.

[0317] 1002. gNB2 sends a first request message to gNB1. Correspondingly, gNB1 receives the first request message from gNB2.

[0318] Among them, the first request information is used to request context information of the terminal device from gNB1.

[0319] 1003. gNB1 determines to migrate the context information of the terminal device to gNB2.

[0320] For example, after receiving the first request, gNB1 determines to migrate the context information of the terminal device to gNB2. It is understandable that gNB1 determines that gNB2 will maintain the terminal device.

[0321] It should be understood that step 1003 is an internal implementation process of gNB1, that is, step 1003 may not be reflected in the operation process.

[0322] 1004. gNB1 sends a retrieval terminal device context feedback message to gNB2. In response, gNB2 receives the retrieval terminal device context feedback message from gNB1.

[0323] It should be understood that the retrieve terminal device context feedback message (eg, Retrieve UE Context Response message) includes context information of the terminal device.

[0324] It should also be understood that the retrieval terminal device context feedback message may include information indicating the first RNA (eg, range information of the first RNA).

[0325] 1005. gNB2 sends an RRC recovery message to the terminal device. Correspondingly, the terminal device receives the RRC recovery message from gNB2.

[0326] For example, after gNB2 receives the Retrieve UE Context Feedback message from gNB1, gNB2 sends an RRC Resume message to the UE. The RRC Resume message indicates that the UE is updated from an Inactive state to a Connected state.

[0327] It should be understood that gNB1 determines to migrate the context information of the terminal device to gNB2. After receiving the context information of the terminal device, gNB2 changes the terminal device from an inactive state to a connected state through an RRC recovery message.

[0328] Among them, after the terminal device enters the connected state, the network device whose coverage range belongs to the first RNA no longer needs to maintain the terminal device in the inactive terminal device managed by itself that is interested in clock-related information. As shown in Figure 10, the network device whose coverage range belongs to the first RNA can be instructed to update the inactive terminal device managed by itself that is interested in clock-related information in the following manner:

[0329] Method 5

[0330] 1006. gNB1 sends a third message to the network device whose coverage range belongs to the first RNA range.

[0331] Accordingly, the network device whose coverage range belongs to the first RNA receives the third message from gNB1.

[0332] For example, gNB1 sends the third message to gNB2.

[0333] It should be understood that since gNB1 migrates the context information of the terminal device to gNB2, the gNB2 knows the first RNA, the second RNA, the first identification information, and one or more of the second identification information corresponding to the terminal device, and the gNB1 sends a third message to the network devices within the coverage range of the first RNA, wherein the gNB1 sends the third message to the network devices other than gNB2 within the coverage range of the first RNA.

[0334] It should also be understood that the above step 1006 is similar to step 806 in FIG. 8 and step 906 in FIG. 9 . For details, please refer to the descriptions in FIG. 8 and FIG. 9 , which will not be repeated here.

[0335] Method 6

[0336] 1007. gNB2 sends a third message to the network device whose coverage range belongs to the first RNA.

[0337] Accordingly, the network device whose coverage range falls within the range of the first RNA receives the third message from gNB2.

[0338] For example, gNB2 sends the third message to gNB1.

[0339] Among them, gNB2 receives a retrieved UE context feedback message from gNB1, and the retrieved UE context feedback message includes information indicating the first RNA (for example, range information of the first RNA). The gNB2 determines the range of the first RNA based on the information indicating the first RNA, and sends a third message to the network device whose coverage range belongs to the range of the first RNA.

[0340] It should also be understood that the above step 1007 is similar to step 806 in FIG. 8 and step 906 in FIG. 9 . For details, please refer to the descriptions in FIG. 8 and FIG. 9 , which will not be repeated here.

[0341] 1008. gNB1 and gNB2 update the inactive terminal devices that are interested in clock-related information and are managed by them.

[0342] gNB1 may perform step 1008 after step 1003. gNB2 may perform step 1008 after step 1004 or after step 1006.

[0343] It should be understood that step 1008 is similar to step 703 in FIG. 7 . For details, please refer to the detailed description in step 703 , which will not be repeated here.

[0344] 1009. gNB1 and gNB2 send clock-related information as needed.

[0345] For example, when gNB1 and gNB2 determine that there is a terminal device among the inactive terminal devices that they manage and are interested in clock-related information, the network device that determines that there is a terminal device among the inactive terminal devices that they manage and are interested in clock-related information sends clock-related information.

[0346] It should be understood that step 1009 is similar to step 810 in FIG. 8 . For details, please refer to the detailed introduction in step 810 , which will not be repeated here.

[0347] It should also be understood that the method shown in FIG. 10 is also applicable to the case where the terminal device changes from an inactive state to an idle state, and will not be described in detail here.

[0348] According to the method shown in Figure 10 above, when the terminal device changes from an inactive state to a connected state or an idle state, that is, when the inactive terminal device leaves the inactive state, gNB1 / gNB2 can promptly notify the network devices whose coverage range is within the first RNA, and the network devices whose coverage range is within the first RNA can promptly update the inactive terminal devices under management that are interested in clock-related information, and send clock-related information on demand, thereby avoiding unnecessary waste of resources in network devices and reducing inter-station interference.

[0349] Scene 3

[0350] During the SDT process, the terminal device is still in an inactive state. The first network device / the second network device instructs the network devices within the coverage range of the first RNA / the second RNA to update the inactive terminal devices managed by itself that are interested in clock-related information. The following will provide an exemplary introduction to a communication method provided in an embodiment of the present application in conjunction with Figure 11.

[0351] FIG11 is a schematic flowchart of another communication method provided in an embodiment of the present application.

[0352] It should be understood that this method initiates an SDT process from an inactive terminal device that is interested in clock-related information to a second network device, where the first network device is gNB1, the second network device is gNB2, the network devices within the coverage range of the first RNA are gNB1 and gNB2, and the network devices within the coverage range of the second RNA are gNB1, gNB2 and gNB3. The method shown in FIG11 is exemplarily introduced.

[0353] 1101. The terminal device performs small data transmission (SDT) to gNB2.

[0354] It should be understood that the SDT process initiated by an inactive terminal device to gNB2 is similar to the existing technology and will not be repeated here.

[0355] 1102. gNB2 sends a second request message to gNB1.

[0356] Accordingly, gNB2 receives the second request information from gNB1.

[0357] The second request information is used to request context information of the terminal device and includes SDT indication information.

[0358] It should be understood that after gNB1 receives the second request information, gNB1 determines whether to migrate the context information of the terminal device to gNB2. gNB1 determines not to migrate the context information of the terminal device to gNB2, as shown in Case 1 in FIG11 ; gNB1 determines to migrate the context information of the terminal device to gNB2, as shown in Case 2 in FIG11 .

[0359] Case 1

[0360] 1103. gNB1 determines not to migrate the context information of the terminal device to gNB2.

[0361] For example, after receiving the second request information, gNB1 determines not to migrate the context information of the terminal device to gNB2. It can be understood that gNB1 determines that gNB1 continues to maintain the terminal device.

[0362] It should be understood that during the SDT process between the terminal device and gNB2, gNB1 will migrate partial context information of the terminal device to gNB2. This partial context information of the terminal device is intended to ensure the smooth progress of the SDT process between the terminal device and gNB2. However, whether gNB1 decides to migrate the context information of the terminal device to gNB2, that is, whether to migrate the complete context information of the terminal device, is determined by gNB1.

[0363] 1104. gNB1 sends a third message to the network device whose coverage area belongs to the first RNA.

[0364] Accordingly, the network device whose coverage area belongs to the first RNA receives the third message from gNB1.

[0365] For example, gNB1 sends the third message to gNB2.

[0366] The third message is used to instruct the terminal device that is interested in the clock-related information to leave the first RNA.

[0367] It should be understood that the second message includes the first identification information of the terminal device. Optionally, the second message may also include range information of the first RNA.

[0368] It should be understood that the terminal device performs SDT transmission with gNB2, meaning that gNB2 can provide clock-related information to the terminal device. gNB1 sends a third message to network devices within the coverage of a first RNA configured by gNB1 for the terminal device, indicating that the inactive terminal device interested in clock-related information has left the coverage of the network device. Accordingly, the network device within the coverage of the first RNA removes the terminal device from its managed list of inactive terminal devices interested in clock-related information based on the third message.

[0369] It should also be understood that when gNB2 is a network device whose coverage range belongs to the first RNA, due to the SDT transmission between the terminal device and gNB2, the gNB1 sends a third message to the network device whose coverage range belongs to the first RNA, which may include: the gNB1 sends a third message to other network devices other than gNB2 whose coverage range belongs to the first RNA.

[0370] It should also be understood that gNB1 sends to gNB2 specific content for indicating the clock-related information of interest to the terminal device. The specific content for indicating the clock-related information of interest to the terminal device may be carried in a third message and sent to gNB2, or may be sent to gNB2 via other signaling bearers.

[0371] It should be understood that when gNB1 determines not to migrate the context information of the terminal device to gNB2, gNB1 terminates the SDT process of the terminal device. The method may further include:

[0372] 1105. gNB1 sends a retrieval of terminal device context failure message to gNB2. In response, gNB2 receives the retrieval of terminal device context failure message from gNB1.

[0373] It should be understood that the UE context retrieval failure message (e.g., the Retrieve UE Context Failure message) includes a second message. The second message includes a second RNA configured by gNB1 for the UE and / or second identification information configured by gNB1 for the UE. For example, the second RNA and / or second identification information are determined by gNB1 based on the UE's RNA-U.

[0374] It should be understood that the second message can be carried in the UE context retrieval failure information and sent by gNB1 to gNB2, or the second message can be sent by gNB1 to gNB2 through other signaling (such as RRC Release message) or through separate signaling.

[0375] It should also be understood that the second message may include a message for instructing the termination of the SDT process.

[0376] 1106. gNB2 sends a message to the terminal device to indicate the termination of the SDT process.

[0377] Accordingly, the terminal device receives a message from gNB2 to terminate the SDT process.

[0378] For example, the gNB2 receives a terminal device context retrieval failure message from gNB1, and the terminal device context retrieval failure message includes the message for terminating the SDT process. The gNB2 sends the message for terminating the SDT process to the terminal device.

[0379] It should be understood that the message for terminating the SDT process can be carried in a second message and sent to the terminal device. For example, gNB2 sends an RRC Release message to the terminal device, where the RRC Release message indicates the termination of the SDT process. Accordingly, the terminal device receives the RRC Release message and terminates the SDT process with gNB2.

[0380] 1107. gNB1 sends a fourth message to the network device within the coverage range of the second RNA.

[0381] Accordingly, the network device within the coverage of the second RNA receives the fourth message from gNB1.

[0382] The fourth message is used to instruct an inactive terminal device that is interested in clock-related information to join the second RNA.

[0383] It should be understood that gNB1 terminates the SDT process for the terminal device, meaning that gNB2 cannot detect whether the terminal device is interested in clock-related information. Specifically, gNB1 configures a second RNA for the terminal device and sends a fourth message to network devices within the coverage of the second RNA. This fourth message is used to instruct the network devices within the coverage of the second RNA that the inactive terminal device with interest in clock-related information has been added to the coverage of the second RNA. Accordingly, the network device within the coverage of the second RNA adds the terminal device to its managed inactive terminal devices with interest in clock-related information based on the fourth message.

[0384] It should be understood that the specific content and function of the third message and the fourth message are similar to those of the third message and the fourth message in Figures 8 to 10. For details, please refer to the detailed introduction in Figures 8 to 10.

[0385] Case 2

[0386] 1103', gNB1 determines the context information of the terminal device to be migrated.

[0387] For example, after receiving the second request, gNB1 determines to migrate the context information of the terminal device to gNB2. It is understood that gNB2 maintains the terminal device.

[0388] At 1104', gNB1 sends a Retrieve UE Context Feedback message to gNB2. In response, gNB2 receives the Retrieve UE Context Feedback message from gNB1.

[0389] It should be understood that the UE context feedback message includes UE context information.

[0390] 1105', gNB1 or gNB2 sends a third message to the network device whose coverage range is within the first RNA. Accordingly, the network device whose coverage range is within the first RNA receives the third message from gNB1 or gNB2.

[0391] It should be understood that the third message is similar to the third message in Figures 8 to 10 above, and will not be repeated here.

[0392] It should also be understood that after receiving the third message, the network device whose coverage range falls within the range of the first RNA deletes the terminal device from the inactive terminal devices managed by itself that are interested in clock-related information according to the third message.

[0393] 1106', gNB2 sends a message to the terminal device to indicate the termination of the SDT process.

[0394] Accordingly, the terminal device receives a message from gNB2 indicating the termination of the SDT process.

[0395] It should be understood that the terminal device terminates the SDT process according to the message from gNB2 indicating the termination of the SDT process.

[0396] Optionally, the message for indicating the termination of the SDT process may be carried in an RRC Release message, or the message for indicating the termination of the SDT process may be sent through separate signaling.

[0397] 1107', gNB2 sends a fourth message to the network device whose coverage area belongs to the second RNA.

[0398] Accordingly, the network device within the coverage of the second RNA receives the fourth message from gNB2.

[0399] The fourth message is used to instruct the terminal device that is interested in clock-related information to join the second RNA.

[0400] It should be understood that gNB1 determines to migrate the context information of the terminal device to gNB2, i.e., gNB2 may terminate the SDT process for the terminal device. gNB2 terminates the SDT process for the terminal device, and network devices within the second RNA cannot perceive whether the terminal device is interested in clock-related information. In other words, gNB2 sends the fourth message to the network devices within the second RNA, instructing the network devices within the second RNA to add the inactive terminal devices interested in clock-related information to the coverage of the network device. Accordingly, the network device within the second RNA, based on the fourth message, adds the terminal device to its managed inactive terminal devices interested in clock-related information.

[0401] It should be understood that the specific content and function of the third message and the fourth message are similar to those of the third message and the fourth message in Figures 8 to 10. For details, please refer to the detailed introduction in Figures 8 to 10.

[0402] 1108. gNB1, gNB2, and gNB3 update the inactive terminal devices that are interested in clock-related information and are managed by them.

[0403] gNB1 may perform step 1108 after step 1106. gNB2 may perform step 1108 after step 1106' or after step 1104'. gNB3 may perform step 1108 after step 1107.

[0404] It should be understood that step 1108 is similar to step 703 in FIG. 7 . For details, please refer to the detailed introduction in step 703 , which will not be repeated here.

[0405] 1109. gNB1, gNB2, and gNB3 send clock-related information as needed.

[0406] For example, when gNB1, gNB2, and gNB3 determine that there is a terminal device among the inactive terminal devices that they manage and are interested in clock-related information, the network device that determines that there is a terminal device among the inactive terminal devices that they manage and are interested in clock-related information sends clock-related information.

[0407] It should be understood that step 1109 is similar to step 810 in FIG. 8 . For details, please refer to the detailed introduction in step 810 , which will not be repeated here.

[0408] According to the method shown in FIG11 , when a terminal device is in an inactive state, the terminal device initiates an SDT process. The network device (e.g., gNB2) performing SDT with the terminal device can sense whether the inactive terminal device is interested in clock-related information, so that gNB1 / gNB2 sends a third message to the network device within the coverage range of the first RNA, for deleting the terminal device from the inactive terminal devices managed by the gNB1 / gNB2 that are interested in clock-related information, thereby avoiding unnecessary resource waste in the network device and reducing inter-station interference. When gNB1 / gNB2 terminates the SDT process for the terminal device, gNB1 / gNB2 sends a fourth message to the network device within the coverage range of the second RNA, for adding the inactive terminal device that is interested in clock-related information to the inactive terminal devices managed by the gNB1 / gNB2 that are interested in clock-related information, thereby avoiding the terminal device from being unable to obtain clock-related information and ensuring the normal operation of related applications of the terminal device.

[0409] Based on the introduction to Scenarios 1, 2, and 3 above, during the RNA-U process, gNB1 and / or gNB2 can send a third message to network devices within the first RNA and / or a fourth message to network devices within the second RNA. This ensures that inactive terminal devices can obtain clock-related information during the RNA update process, ensuring normal operation. Furthermore, this allows network devices to promptly update managed inactive terminal devices that are interested in clock-related information, preventing unnecessary clock-related information transmission and reducing resource waste and inter-station interference.

[0410] It should be understood that, based on the descriptions in Figures 8 to 11 above, gNB1 may determine that the RNA of a terminal device has been updated, or that the terminal device has updated its RNA, based on one or more of the following: terminal device context information, the terminal device changing from an inactive state to a connected state, and the terminal device undergoing an SDT process. In conjunction with the descriptions in Figures 8 and 9 above, gNB2 requests the terminal device's context information from gNB1, and gNB1 determines that the terminal device has updated its RNA. In conjunction with the description in Figure 10 above, gNB2 requests and obtains the terminal device's context information from gNB1, and gNB2 instructs the terminal device to change from an inactive state to a connected state, and gNB1 determines that the terminal device has updated its RNA. In conjunction with the description in Figure 11 above, an SDT is performed between the terminal device and gNB2, and gNB2 requests the terminal device's context information from gNB1, and gNB1 determines that the terminal device has updated its RNA.

[0411] The method embodiment of the present application is described above in conjunction with the accompanying drawings. The device embodiment of the present application is described below. It can be understood that the description of the method embodiment and the description of the device embodiment can correspond to each other. Therefore, for parts not described, reference can be made to the previous method embodiment.

[0412] It can be understood that in the above-mentioned method embodiments, the methods and operations implemented by the terminal device can also be implemented by components that can be used for the terminal device (such as chips or circuits), and the methods and operations implemented by the network device can also be implemented by components that can be used for the network device (such as chips or circuits).

[0413] It can be understood that, unless otherwise specified or there is a logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referenced to each other, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0414] It is understood that in this application, the terms "first," "second," and various numerical references (e.g., #1, #2, etc.) are used to distinguish between different messages for ease of description and are not intended to limit the scope of the embodiments of this application. For example, they are used to distinguish between different messages, rather than to describe a specific order or precedence. It is understood that the objects described in this manner can be interchanged where appropriate to enable description of scenarios other than the embodiments of this application.

[0415] It is understood that in this application, "protocol" may refer to a standard protocol in the field of communications, such as 5G protocol, NR protocol, and related protocols used in future communication systems, and this application does not limit this. "Predefined" may include pre-definition. For example, protocol definition. "Preconfiguration" can be implemented by pre-saving corresponding codes, tables, or other methods that can be used to indicate relevant information in the device, and this application does not limit its specific implementation method.

[0416] The above mainly introduces the solution provided by the embodiment of the present application from the perspective of the interaction between various network elements. It can be understood that each network element, such as a transmitting end device or a receiving end device, includes a hardware structure and / or software module corresponding to the execution of each function in order to implement the above functions. Those skilled in the art should be aware that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in a hardware or computer software driven hardware manner depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0417] In the embodiment of the present application, the functional modules of the transmitting device or the receiving device can be divided according to the above method example. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical functional division. There may be other division methods in actual implementation. The following is an example of dividing each functional module according to each function.

[0418] FIG12 is a schematic structural diagram of a communication device provided in an embodiment of the present application.

[0419] The device 1200 includes a transceiver unit 1210 and a processing unit 1220 , wherein the transceiver unit 1210 can be used to implement corresponding communication functions, and the processing unit 1220 can be used to perform data processing.

[0420] Optionally, the transceiver unit 1210 may also be referred to as a communication interface or a communication unit, and includes a transmitting unit and / or a receiving unit. The transceiver unit 1210 may be a transceiver (including a transmitter and / or a receiver), an input / output interface (including an input and / or output interface), a pin, or a circuit. The transceiver unit 1210 may be configured to perform the sending and / or receiving steps in the above-described method embodiments.

[0421] Optionally, the processing unit 1220 may be a processor (may include one or more), a processing circuit with processor functions, etc., and may be used to execute other steps except sending and receiving in the above method embodiment.

[0422] Optionally, the apparatus 1200 further includes a storage unit, which may be a memory, an internal storage unit (e.g., a register, a cache, etc.), an external storage unit (e.g., a read-only memory, a random access memory, etc.), etc. The storage unit is used to store instructions, and the processing unit 1220 executes the instructions stored in the storage unit to cause the communication apparatus to perform the above method.

[0423] In one design, the apparatus 1200 may correspond to the network device (eg, the first network device or the second network device) in the above method embodiments, or a component of the network device (eg, a chip).

[0424] In another design, the apparatus 1200 may correspond to the terminal device in the above method embodiment, or a component (such as a chip) of the terminal device.

[0425] The device 1200 can implement the steps or processes executed by the terminal device in the above method embodiment, wherein the transceiver unit 1210 can be used to perform the transceiver-related operations of the terminal device in the above method embodiment, and the processing unit 1220 can be used to perform the internal device operations of the terminal device in the above method embodiment except for sending and receiving information.

[0426] In one possible implementation, the processing unit 1220 is used to determine whether the terminal device is interested in clock-related information; when the terminal device is in an inactive state, the transceiver unit 1210 is used to send a first message to the second network device, and the first message indicates that the terminal device sends clock-related information within the coverage of the second network device.

[0427] The device 1200 can implement the steps or processes executed by the first network device in the above method embodiment, wherein the transceiver unit 1210 can be used to perform the transceiver-related operations of the first network device in the above method embodiment, and the processing unit 1220 can be used to perform the internal operations of the first network device in the above method embodiment except for sending and receiving information.

[0428] In one possible implementation, the transceiver unit 1210 is used to receive a first message from a first network device, wherein the first message indicates that an inactive terminal device sends clock-related information within the coverage of a second network device; the transceiver unit 1210 is used to send clock-related information within the coverage of the second network device indicated by the first message.

[0429] When the device 1200 is used to execute the method in Figures 7 to 11, the transceiver unit 1210 can be used to execute the steps of sending and receiving information in the method; the processing unit 1220 can be used to execute the steps inside the device in the method except sending and receiving information.

[0430] It should be understood that the specific process of each unit executing the above corresponding steps has been described in detail in the above method embodiment, and for the sake of brevity, it will not be repeated here.

[0431] It should also be understood that the device 1200 here is embodied in the form of a functional unit. The term "unit" here can refer to an application specific integrated circuit (ASIC), an electronic circuit, a processor (such as a shared processor, a dedicated processor or a group processor, etc.) and a memory for executing one or more software or firmware programs, a combined logic circuit and / or other suitable components that support the described functions. In an optional example, those skilled in the art will understand that the device 1200 can be specifically a network device in the above-mentioned embodiment, and can be used to execute the various processes and / or steps corresponding to the network device in the above-mentioned method embodiments. To avoid repetition, they will not be described here.

[0432] The apparatus 1200 of each of the above-mentioned solutions has the function of implementing the corresponding steps performed by the devices (such as terminal devices and network devices) in the above-mentioned methods. This function can be implemented by hardware, or the corresponding software implementation can be executed by hardware. The hardware or software includes one or more modules corresponding to the above-mentioned functions; for example, the transceiver unit can be replaced by a transceiver (for example, the sending unit in the transceiver unit can be replaced by a transmitter, and the receiving unit in the transceiver unit can be replaced by a receiver), and other units, such as the processing unit, can be replaced by a processor to respectively perform the sending and receiving operations and related processing operations in each method embodiment.

[0433] In addition, the transceiver unit 1210 may also be a transceiver circuit (for example, may include a receiving circuit and a transmitting circuit), and the processing unit may be a processing circuit.

[0434] It should be noted that the apparatus in FIG12 may be a network element or device in the aforementioned embodiment, or may be a chip or chip system, such as a system on chip (SoC). The transceiver unit may be an input / output circuit or a communication interface; the processing unit may be a processor, microprocessor, or integrated circuit integrated on the chip. This is not limited here.

[0435] Figure 13 is a schematic diagram of the structure of a communication device 1300 provided in an embodiment of the present application. The communication device 1300 shown in Figure 13 includes a processor 1310, a memory 1320, and a transceiver 1330. The processor 1310 is coupled to the memory 1320 and is configured to execute instructions stored in the memory 1320 to control the transceiver 1330 to transmit and / or receive signals.

[0436] It should be understood that the processor 1310 and memory 1320 described above can be combined into a single processing device, with the processor 1310 configured to execute program code stored in the memory 1320 to implement the aforementioned functions. In a specific implementation, the memory 1320 can also be integrated into the processor 1310 or independent of the processor 1310. It should be understood that the processor 1310 can also correspond to the various processing units in the aforementioned communication device, and the transceiver 1330 can correspond to the various receiving units and transmitting units in the aforementioned communication device.

[0437] It should also be understood that the transceiver 1330 may include a receiver (or receiver) and a transmitter (or transmitter). The transceiver may further include an antenna, and the number of antennas may be one or more. The transceiver may also be a communication interface or interface circuit.

[0438] Specifically, the communication device 1300 may correspond to the devices (terminal device, first network device, second network device) in Figures 7 to 11 according to the embodiments of the present application. The communication device 1300 may include units of the method performed by the terminal device in Figures 7 to 11, or units of the method performed by the first network device, or units of the method performed by the second network device. It should be understood that the specific process of each unit performing the above-mentioned corresponding steps has been described in detail in the above-mentioned method embodiment, and for the sake of brevity, it will not be repeated here.

[0439] When the communication device 1300 is a chip, the chip includes an interface unit and a processing unit, wherein the interface unit may be an input / output circuit or a communication interface; and the processing unit may be a processor, microprocessor, or integrated circuit integrated on the chip.

[0440] During implementation, each step of the above method can be completed by an integrated logic circuit of the hardware in the processor or by instructions in the form of software. The steps of the method disclosed in conjunction with the embodiments of the present application can be directly embodied as being executed by a hardware processor, or can be executed by a combination of hardware and software modules in the processor. The software module can be located in a storage medium mature in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in conjunction with its hardware. To avoid repetition, it will not be described in detail here.

[0441] It should be noted that the processor in the embodiments of the present application can be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method embodiment can be completed by an integrated logic circuit of the hardware in the processor or by instructions in the form of software. The above processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component. The various methods, steps, and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor. The steps of the method disclosed in the embodiments of the present application can be directly embodied as being executed by a hardware decoding processor, or can be executed by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium mature in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, registers, etc. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0442] The present application also provides a computer-readable medium having a computer program stored thereon, which implements the functions of any of the above method embodiments when executed by a computer.

[0443] The present application also provides a computer program product, which implements the functions of any of the above method embodiments when executed by a computer.

[0444] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware, or any combination thereof. When implemented using software, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated therein. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a high-density digital video disc (DVD)), or a semiconductor medium (eg, a solid state disk (SSD)).

[0445] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0446] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0447] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0448] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0449] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0450] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0451] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

[0452] As used in this specification, the terms "component," "module," "system," and the like are used to represent computer-related entities, hardware, firmware, a combination of hardware and software, software, or software in execution. For example, a component can be, but is not limited to, a process running on a processor, a processor, an object, an executable file, an execution thread, a program, and / or a computer. By way of illustration, both an application running on a computing device and a computing device can be a component. One or more components can reside in a process and / or an execution thread, and a component can be located on a computer and / or distributed between two or more computers. In addition, these components can be executed from various computer-readable media having various data structures stored thereon. Components can communicate, for example, via local and / or remote processes based on signals having one or more data packets (e.g., data from two components interacting with another component on a local system, a distributed system, and / or a network, such as the Internet interacting with other systems via signals).

[0453] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

Claims

1. A communication method, characterized in that, Including: The first network device determines that the terminal device is interested in clock-related information; When the terminal device is in the inactive state, the first network device sends a first message to the second network device, and the first message instructs to send the clock-related information for the terminal device within the coverage area of the second network device.

2. The method according to claim 1, wherein The method further includes: The first network device sends a second message to the terminal device, the second message instructs the terminal device to enter the inactive state from the connected state, and the second message includes information indicating a first radio access network notification area RNA, and the first RNA includes the coverage area of the second network device.

3. The method according to claim 1 or 2, characterized in that, The first message includes the first identification information of the terminal device and / or information on the coverage area of the second network device.

4. The method according to any one of claims 1 to 3, characterized in that, The first message includes the clock-related information and / or the duration information of a timer, and the duration information of the timer is used to indicate the duration for maintaining the terminal device interested in the clock-related information.

5. The method according to claim 4, wherein The clock-related information includes clock information and / or clock synchronization status information.

6. The method according to any one of claims 1 to 5, characterized in that, When the RNA of the terminal device is updated, the method further includes: The first network device sends a third message to a network device whose coverage area belongs to the first RNA, and the third message is used to instruct the terminal device interested in the clock-related information to leave the first RNA.

7. The method according to any one of claims 1 to 6, characterized in that, When the RNA of the terminal device is updated, the method further includes: The first network device sends a fourth message to a network device whose coverage area belongs to the second RNA, and the fourth message is used to instruct the terminal device interested in the clock-related information to join the second RNA.

8. The method according to any one of claims 1 to 5, characterized in that, When the RNA of the terminal device is updated, the method further includes: The first network device sends a fifth message to a network device whose coverage area belongs to the first RNA, and the fifth message is used to indicate that the information of the terminal device interested in the clock-related information has changed.

9. The method according to claim 8, wherein The fifth message includes the first identification information of the terminal device.

10. The method according to any one of claims 6 to 9, characterized in that, When the RNA of the terminal device is updated, the reason for the update is related to one or more of the following: The context information of the terminal device, the change of the terminal device from the inactive state to the connected state, and the small data transfer SDT process of the terminal device.

11. A communication method, characterized in that, Including: The second network device receives a first message from the first network device, and the first message instructs to send clock-related information for a terminal device in the inactive state within the coverage area of the second network device; The second network device sends the clock-related information within the coverage area of the second network device indicated by the first message according to the first message.

12. The method according to claim 11, wherein The first message includes the first identification information of the terminal device and / or the coverage area of the second network device.

13. The method according to claim 11 or 12, characterized in that, The first message further includes the clock-related information and / or the duration information of a timer, and the duration information of the timer is used to maintain the duration of the terminal device interested in the clock-related information.

14. The method according to claim 13, wherein The clock-related information includes clock information and / or clock synchronization status information.

15. The method according to any one of claims 11 to 14, characterized in that The method further includes: The second network device updates the inactive terminal devices interested in the clock-related information and managed by the second network device according to the first message.

16. The method according to any one of claims 11 to 15, characterized in that, The radio access network notification area (RNA) of the terminal device is updated, and the method further includes: The second network device receives a third message from the first network device, where the third message is used to indicate that the terminal device interested in the clock-related information leaves a first RNA, and the first RNA includes the coverage area of the second network device.

17. The method according to any one of claims 11 to 16, characterized in that, The RNA of the terminal device is updated, and the method further includes: The second network device receives a fourth message from the first network device, where the fourth message is used to indicate that the terminal device interested in the clock-related information joins a second RNA, and the second RNA includes the coverage area of the second network device.

18. The method according to any one of claims 11 to 15, characterized in that, The RNA of the terminal device is updated, and the method further includes: The second network device sends a third message to the network devices whose coverage areas belong to the first RNA, where the third message is used to indicate that the terminal device interested in the clock-related information leaves the first RNA.

19. The method according to any one of claims 11 to 16 and 18, characterized in that, The RNA of the terminal device is updated, and the method further includes: The second network device sends a fourth message to the network devices whose coverage areas belong to the second RNA, where the fourth message is used to indicate that the terminal device interested in the clock-related information joins the second RNA.

20. The method according to any one of claims 16 to 19, characterized in that, The RNA of the terminal device is updated, and the reason for the update is related to one or more of the following: The context information of the terminal device, the change of the terminal device from the inactive state to the connected state, and the small data transmission (SDT) process of the terminal device.

21. A communication device, characterized in that, The communication device includes a unit or module for executing the method according to any one of claims 1-10, 11-20.

22. A communication device, characterized in that, including: a processor, the processor is coupled to a memory, and the processor is used to call the computer program instructions stored in the memory to execute the method according to any one of claims 1-10, or the method according to any one of claims 11-20.

23. A chip, characterized in that, including a processor and a communication interface, the communication interface is used to receive data and / or information, and transmit the received data and / or information to the processor, and the processor processes the data and / or information to execute the method according to any one of claims 1-10, or the method according to any one of claims 11-20.

24. A computer-readable storage medium, characterized in that, Instructions are stored on the computer-readable storage medium, and when the instructions run on a computer, the computer is caused to execute the method according to any one of claims 1-10, or the computer is caused to execute the method according to any one of claims 11-20.

25. A computer program product, characterized in that, Instructions are stored on the computer-readable storage medium, and when the instructions run on a computer, the computer is caused to execute the method according to any one of claims 1-10, or the computer is caused to execute the method according to any one of claims 11-20.

Images