Capability synchronization method and system, and related apparatus

Abstract

Disclosed in the present application are a capability synchronization method and system, and a related apparatus. A UE comprises an NTN communication module and a mobile communication module. After the mobile communication module is registered to a TN-CN, the NTN communication module executes a registration process of an NTN-CN by means of the mobile communication module, a TN-RAN and the TN-CN; and the NTN-CN acquires NTN air-interface capability information of the UE from the NTN communication module by means of the TN-CN, the TN-RAN and the mobile communication module. In this way, since the NTN-CN acquires, under a TN network, the NTN air-interface capability information of the UE, there is no need for the NTN-CN to reacquire, under the NTN, the NTN air-interface capability information of the UE, thereby reducing the signaling overheads of transmitting the NTN air-interface capability information of the UE between the UE and a non-terrestrial network-core network, shortening the time required for the UE to transmit, under the NTN, the NTN air-interface capability information of the UE, and reducing the power consumption of the UE.

Description

A capability synchronization method, system and related device

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on October 28, 2023, with application number 202311427500.9 and application name “A Capability Synchronization Method, System and Related Devices”, 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 in particular to a capability synchronization method, system, and related devices. Background Art

[0003] Currently, some user equipment (UE) supports non-terrestrial network (NTN) communication capabilities. With the advancement of communication technology, more and more UE will support NTN communication capabilities in the future. UEs with NTN communication capabilities can communicate via satellite in areas such as oceans, deserts, grasslands, high altitudes, and uninhabited areas where mobile communication coverage is lacking, impossible, or where communication systems are disrupted.

[0004] When a UE communicates with a non-terrestrial network device, the non-terrestrial network device needs to provide the UE with corresponding communication resources based on the UE's NTN air interface capability information. Because the UE has a large amount of NTN air interface capability information, the UE needs to occupy more air interface resources when sending this information to the non-terrestrial network device, which increases the transmission time and UE power consumption.

[0005] Summary of the Invention

[0006] The present application provides a capability synchronization method, system, and related devices, wherein a UE includes an NTN communication module and a mobile communication module. The mobile communication module obtains the registration information of the NTN communication module. After the mobile communication module registers with the core network of the terrestrial network, the NTN communication module executes the registration process of the core network of the non-terrestrial network through the mobile communication module and the core network of the terrestrial network. The core network of the non-terrestrial network obtains the NTN air interface capability information of the UE from the NTN communication module of the UE through the core network of the terrestrial network. After searching for the NTN-RAN, the NTN communication module of the UE accesses the core network of the non-terrestrial network. The core network of the non-terrestrial network obtains the NTN air interface capability information of the UE in the terrestrial network, saving the air interface resources of the non-terrestrial network and reducing the time for the UE in the non-terrestrial network to transmit the NTN air interface capability information of the UE to the core network of the non-terrestrial network.

[0007] In a first aspect, the present application provides a capability synchronization method, which is applied to a communication system, the communication system including a user equipment (UE), a core network (NTN-CN) device of a non-terrestrial network, a radio access network (NTN-RAN) device of a non-terrestrial network, and a terrestrial network device; the method comprising: the UE receiving a first non-terrestrial network air interface capability request sent by the terrestrial network device, and sending a first non-terrestrial network air interface capability message to the terrestrial network device, where the first non-terrestrial network air interface capability message includes the UE's NTN air interface capability information;

[0008] The terrestrial network device sends a second non-terrestrial network air interface capability message to the NTN-CN device, where the second non-terrestrial network air interface capability message includes the NTN air interface capability information of the UE;

[0009] The UE searches for the NTN and sends a first mobility registration request message to the NTN-CN device through the NTN-RAN device. The first mobility registration request message is used for the UE to register with the NTN-CN device.

[0010] After receiving the first mobility registration request message, the NTN-CN device sends the UE's NTN air interface capability information to the NTN-RAN device. This allows the UE to send the NTN air interface capability information to the terrestrial network device in the TN. The NTN-CN device does not need to obtain the UE's NTN air interface capability information in the NTN, thus conserving NTN air interface resources.

[0011] In some examples, the UE searching for the NTN means that the UE receives a signal sent by the NTN-RAN.

[0012] In one possible implementation, before the UE receives the first non-terrestrial network air interface capability request, the method further includes: after the UE successfully registers with the NTN-CN device via the terrestrial network device, the NTN-CN device sends a second non-terrestrial network air interface capability request to the terrestrial network device, where the second non-terrestrial network air interface capability request is used by the NTN-CN device to obtain the UE's NTN air interface capability information; and after receiving the second non-terrestrial network air interface capability request, the terrestrial network device sends the first non-terrestrial network air interface capability request to the UE. In this way, after the UE successfully registers with the NTN-CN device via the terrestrial network device, the NTN-CN device can obtain the UE's NTN air interface capability information via the terrestrial network device.

[0013] In one possible implementation, the terrestrial network equipment includes a terrestrial network radio access network (TN-RAN) equipment and a terrestrial network core network (TN-CN) equipment; after receiving a second non-terrestrial network air interface capability request, the terrestrial network equipment sends a first non-terrestrial network air interface capability request to the UE, specifically including: the TN-CN equipment receives the second non-terrestrial network air interface capability request and sends the first non-terrestrial network air interface capability request to the TN-RAN equipment; the TN-RAN equipment receives the first non-terrestrial network air interface capability request and sends the first non-terrestrial network air interface capability request to the UE. In this way, after receiving the second non-terrestrial network air interface capability request sent by the NTN-CN equipment, the TN-CN equipment can send the first non-terrestrial network air interface capability request to the UE in response to the second non-terrestrial network air interface capability request.

[0014] In some examples, the second non-terrestrial network air interface capability request is an N1 NTN Container (UE Capability Enquiry) or an N1NTN Container (UE Capability Info Request), and the first non-terrestrial network air interface capability request is a non-access layer NAS message or a radio resource control layer RRC message including the second non-terrestrial network air interface capability request.

[0015] In one possible implementation, the terrestrial network equipment includes a TN-CN device and a TN-RAN device; after receiving the second non-terrestrial network air interface capability request, the terrestrial network equipment sends the first non-terrestrial network air interface capability request to the UE, specifically including: the TN-CN device receives the second non-terrestrial network air interface capability request and sends the second non-terrestrial network air interface capability request to the TN-RAN device; the TN-RAN device receives the second non-terrestrial network air interface capability request and sends the first non-terrestrial network air interface capability request to the UE. In this way, after receiving the second non-terrestrial network air interface capability request sent by the NTN-CN device through the TN-CN device, the TN-RAN device can send the first non-terrestrial network air interface capability request to the UE in response to the second non-terrestrial network air interface capability request.

[0016] In one possible implementation, the terrestrial network device includes a TN-RAN device; before the UE receives the first non-terrestrial network air interface capability request, the method further includes: after the UE successfully registers with the NTN-CN device via the TN-RAN device, the NTN-CN device sending the first non-terrestrial network air interface capability request to the TN-RAN device; and after receiving the first non-terrestrial network air interface capability request, the TN-RAN device sends the first non-terrestrial network air interface capability request to the UE. In this way, the UE sends signaling to the NTN-CN device via the TN-RAN device, saving air interface resources of the NTN-RAN device.

[0017] In one possible implementation, the terrestrial network device includes a TN-RAN device; before the UE receives the first non-terrestrial network air interface capability request, the method further includes: after the UE successfully registers with the NTN-CN device through the TN-RAN device, the NTN-CN device sending a second non-terrestrial network air interface capability request to the TN-RAN device, where the second non-terrestrial network air interface capability request is used by the NTN-CN device to obtain the UE's NTN air interface capability information; and after receiving the second non-terrestrial network air interface capability request, the TN-RAN device sends the first non-terrestrial network air interface capability request to the UE. In this way, the UE sends signaling to the NTN-CN device through the TN-RAN device, saving air interface resources of the NTN-RAN device.

[0018] In one possible implementation, the terrestrial network device sends the second non-terrestrial network air interface capability message to the NTN-CN device, specifically including: the TN-RAN device sends the second non-terrestrial network air interface capability message to the NTN-CN device. In this way, the NTN-CN device obtains the NTN air interface capability information of the UE under the TN.

[0019] In one possible implementation, the UE includes a mobile communication module and an NTN communication module; the UE receives the first non-terrestrial network air interface capability request through the mobile communication module; the mobile communication module of the UE generates a first non-terrestrial network air interface capability message based on the NTN air interface capability information provided by the NTN communication module, and sends the first non-terrestrial network air interface capability message to the terrestrial network device.

[0020] In one possible implementation, the ground network device sends the second non-terrestrial network air interface capability message to the NTN-CN device, specifically including: the ground network device sends the second non-terrestrial network air interface capability message to the NTN-CN device in response to the first non-terrestrial network air interface capability message. In this way, after receiving the NTN air interface capability information, the ground network directly forwards the information to the NTN-CN device.

[0021] In a possible implementation, the first non-terrestrial network air interface capability message is a user equipment capability information UE Capability Information message, and the second non-terrestrial network air interface capability message is a user equipment capability information indication UE Capability Infor Indication message.

[0022] In one possible implementation, a UE includes a mobile communication module and an NTN communication module; the UE receives a first non-terrestrial network air interface capability request sent by a terrestrial network device, specifically including: the UE's mobile communication module receives the first non-terrestrial network air interface capability request and obtains the UE's NTN air interface capability information from the NTN communication module; the UE's mobile communication module generates a first non-terrestrial network air interface capability message based on the NTN air interface capability information; and sending the first non-terrestrial network air interface capability message to the terrestrial network device, specifically including: the UE's mobile communication module sends the first non-terrestrial network air interface capability message to the terrestrial network device. In this way, the UE can send the NTN air interface capability information to the terrestrial network device via the mobile communication module.

[0023] In one possible implementation, the terrestrial network device sends a first non-terrestrial network air interface capability request to the UE. Specifically, the terrestrial network device sends a first capability change message to the NTN-CN device via the terrestrial network device after the UE's NTN air interface capability is changed. The first capability change message is used to indicate the change in the UE's NTN air interface capability. In response to the first capability change message, the NTN-CN device sends the first non-terrestrial network air interface capability request to the UE via the terrestrial network device. In this way, the UE can trigger the TN-CN device to obtain NTN air interface capability information.

[0024] In one possible implementation, the terrestrial network device includes a TN-CN device; before the UE receives the first non-terrestrial network air interface capability request, the method further includes: after the UE successfully registers with the TN-CN device via the terrestrial network device, the terrestrial network device sends the first non-terrestrial network air interface capability request to the UE. In this way, the TN-CN device can obtain and store the UE's NTN air interface capability information, and when the NTN-CN device needs to obtain the UE's NTN air interface capability information, it can directly obtain it from the TN-CN device.

[0025] In one possible implementation, the terrestrial network device sends a first non-terrestrial network air interface capability request to the UE, specifically including: after the UE successfully registers with the TN-CN device through the terrestrial network device, the UE sends a first capability change message to the TN-CN device, where the first capability change message is used to indicate a change in the UE's NTN air interface capability; the TN-CN device responds to the first capability change message and sends a second non-terrestrial network air interface capability request to the TN-RAN device; the TN-RAN device responds to the second non-terrestrial network air interface capability request and sends the first non-terrestrial network air interface capability request to the UE; or, the TN-CN device responds to the first capability change message and sends the first non-terrestrial network air interface capability request to the UE via the TN-RAN device. In this way, the UE can trigger the TN-CN device to obtain NTN air interface capability information.

[0026] In a possible implementation, the first capability change message is a second mobility registration request message, and the second mobility registration request message includes a parameter for indicating the change of the NTN air interface capability of the UE; or the first capability change message is a user equipment capability release command message.

[0027] In one possible implementation, the method further includes: after the NTN-CN device receives the first mobility registration request message, sending a first capability synchronization message to the TN-CN device, where the first capability synchronization message is used to obtain the NTN air interface capability information of the UE from the TN-CN device; and the terrestrial network device sending a second non-terrestrial network air interface capability message to the NTN-CN device, specifically including: the TN-CN device sending the second non-terrestrial network air interface capability message to the NTN-CN device in response to the first capability synchronization message. In this way, the NTN-CN device sends the NTN air interface capability information to the NTN-RAN device.

[0028] In a possible implementation, sending the NTN air interface capability information of the UE to the NTN-RAN device specifically includes: the NTN-CN device sending an initial context setup request message to the NTN-RAN device, where the initial context setup request message includes the NTN air interface capability information of the UE.

[0029] In a possible implementation, the first non-terrestrial network air interface capability request is a user equipment capability query UE capability enquiry (NTN) message, and the second non-terrestrial network air interface capability request is a non-terrestrial network air interface capability information request NTN capability info request.

[0030] In one possible implementation, the NTN air interface capability information includes the carriers supported by the UE, the UE's antenna polarization, the UE's maximum transmit power, and the UE's duplex mode. In this way, the NTN-CN and NTN-RAN devices can configure air interface resources and communication modes for the UE based on the NTN air interface capability information.

[0031] In a possible implementation, if the NTN-CN device does not receive the NTN air interface capability information of the UE sent by the TN-CN device, the NTN-CN device sends a third non-terrestrial network air interface capability request to the UE through the NTN-RAN device.

[0032] In a second aspect, the present application provides a capability synchronization method, applied to a user equipment (UE), comprising: the UE receiving a first non-terrestrial network air interface capability request sent by a terrestrial network device, the first non-terrestrial network air interface capability request being used to obtain the UE's NTN air interface capability information; after receiving the first non-terrestrial network air interface capability request, the UE sending a first non-terrestrial network air interface capability message to the terrestrial network device, the first non-terrestrial network air interface capability message including the UE's NTN air interface capability information; after searching for a non-terrestrial network (NTN), the UE sending a mobility registration request message to a core network (NTN-CN) device of the non-terrestrial network, the mobility registration request message being used to notify the NTN-CN device to send the UE's NTN air interface capability information to an NTN-RAN device. In this way, the UE receives a request for obtaining NTN air interface capability information under the TN, and the UE can send the NTN air interface capability information to the core network device under the TN.

[0033] In one possible implementation, before the UE receives the first non-terrestrial network air interface capability request sent by the terrestrial network device, the method further includes: the UE registering with the NTN-CN device through the terrestrial network device. In this way, the UE registers with the NTN-CN device through the terrestrial network device, and the NTN-CN device can send the first non-terrestrial network air interface capability request to the UE to obtain the UE's NTN air interface capability information.

[0034] In one possible implementation, before the UE receives the first non-terrestrial network air interface capability request sent by the terrestrial network device, the method further includes: the UE registering with the TN-CN device. In this way, after the UE registers with the TN-CN device via the TN device, the TN-CN device can send the first non-terrestrial network air interface capability request to the UE to obtain the UE's NTN air interface capability information.

[0035] In one possible implementation, before the UE receives the first non-terrestrial network air interface capability request sent by the terrestrial network device, the method further includes: the UE sends a first capability change message to the TN-CN device, and the first capability change message is used to indicate that the UE's NTN air interface capability has changed.

[0036] In this way, after receiving the first capability change message, the TN-CN device can send a first non-terrestrial network air interface capability request to the UE in response to the first capability change message to obtain the changed NTN air interface capability information of the UE. Alternatively, after receiving the first capability change message, the TN-CN device can send the first capability change message to the NTN-CN device, and the NTN-CN device can send a second non-terrestrial network air interface capability request to the TN-CN device in response to the first capability change message. The TN-CN device can send the first non-terrestrial network air interface capability request to the UE in response to the second non-terrestrial network air interface capability request.

[0037] In a third aspect, the present application provides a capability synchronization method, applied to a non-terrestrial network device (NTN-CN). The method includes: the NTN-CN device sends a first non-terrestrial network air interface capability request to a user equipment (UE) via a terrestrial network device, the first non-terrestrial network air interface capability request being used to obtain the UE's NTN air interface capability information; the NTN-CN device receives a first non-terrestrial network air interface capability message sent by the UE via the terrestrial network device, the first non-terrestrial network air interface capability message including the UE's NTN air interface capability information; and after receiving a mobility registration request message sent by the UE, the NTN-CN device sends the UE's NTN air interface capability information to a first radio access network (NTN-RAN) device of the non-terrestrial network, the first mobility registration request message being used to register the UE with the NTN-CN device. In this way, the NTN-CN device can obtain the UE's NTN air interface capability information via the terrestrial network device, thereby saving NTN air interface resources.

[0038] In one possible implementation, before the NTN-CN device sends the first non-terrestrial network air interface capability request to the UE via the terrestrial network device, the method further includes: the NTN-CN device accepting the UE's initial registration request via the terrestrial network device. Thus, the NTN-CN device accepts the UE's initial registration request via the terrestrial network device, and the NTN-CN device may send the first non-terrestrial network air interface capability request to the UE via the terrestrial network device to obtain the UE's NTN air interface capability information.

[0039] In one possible implementation, the NTN-CN device sends a first non-terrestrial network air interface capability request to the UE via the terrestrial network device. Specifically, the NTN-CN device receives a first capability change message sent by the UE via the terrestrial network device, where the first capability change message indicates that the UE's NTN air interface capability has changed; and in response to the first capability change message, the NTN-CN device sends the first non-terrestrial network air interface capability request to the UE via the terrestrial network device. Thus, the NTN-CN device receives the first capability change message sent by the UE via the terrestrial network device, determines that the UE's NTN air interface capability has changed, and sends the first non-terrestrial network air interface capability request to the UE via the terrestrial network device to obtain the UE's changed NTN air interface capability information.

[0040] In a fourth aspect, the present application provides a capability synchronization method, applied to a non-terrestrial network device (NTN-CN). The method includes: after receiving a first mobility registration request message sent by a UE, the NTN-CN device sends a first capability synchronization message to a core network (TN-CN) device of a terrestrial network, the first capability synchronization message being used to obtain the UE's NTN air interface capability information from the TN-CN device; the NTN-CN device receives a first non-terrestrial network air interface capability message sent by the TN-CN device, the first non-terrestrial network air interface capability message including the UE's NTN air interface capability information; and the NTN-CN device sends the UE's NTN air interface capability information to a non-terrestrial network radio access network (NTN-RAN) device. In this way, the NTN-CN device can obtain the UE's NTN air interface capability information through the terrestrial network device, thereby conserving NTN air interface resources.

[0041] In a fifth aspect, the present application provides a capability synchronization method applied to a core network (TN-CN) device in a terrestrial network. The method includes: the TN-CN device sending a first non-terrestrial network air interface capability request to a user equipment (UE), the first non-terrestrial network air interface capability request being used to obtain the UE's NTN air interface capability information; the TN-CN device receiving a first non-terrestrial network air interface capability message sent by the UE, the first non-terrestrial network air interface capability message including the UE's NTN air interface capability information; and the TN-CN device sending a second non-terrestrial network air interface capability message to the core network (NTN-CN) device in the non-terrestrial network, the second non-terrestrial network air interface capability message including the UE's NTN air interface capability information. In this way, the TN-CN device can help the NTN-CN device obtain the UE's NTN air interface capability information, thereby saving NTN air interface resources.

[0042] In one possible implementation, the TN-CN device sends a first non-terrestrial network air interface capability request to a user equipment (UE), specifically including: the TN-CN device receives a second non-terrestrial network air interface capability request sent by the NTN-CN device; and the TN-CN device sends a first non-terrestrial network air interface capability request to the UE in response to the second non-terrestrial network air interface capability request. Thus, after receiving the second non-terrestrial network air interface capability request from the NTN-CN device to obtain the UE's NTN air interface capability information, the TN-CN device sends the first non-terrestrial network air interface capability request to the UE to obtain the UE's NTN air interface capability information.

[0043] In one possible implementation, the TN-CN device sends a first non-terrestrial network air interface capability request to the user equipment UE, specifically including: after the TN-CN device accepts the UE's initial registration request, sending the first non-terrestrial network air interface capability request to the UE. In this way, after receiving the initial registration request from the UE supporting the NTN communication function, the TN-CN device obtains the UE's NTN air interface capability information and synchronizes the information with the NTN-CN device.

[0044] In one possible implementation, the TN-CN device sends a second non-terrestrial network air interface capabilities message to the core network NTN-CN device of the non-terrestrial network. Specifically, the TN-CN device receives a first capabilities synchronization message sent by the NTN-CN device; and the TN-CN device responds to the first capabilities synchronization message and sends the second non-terrestrial network air interface capabilities message to the NTN-CN device. In this way, the TN-CN device stores the NTN air interface capabilities information of the UE and, upon receiving the first capabilities synchronization message from the NTN-CN device, sends the NTN air interface capabilities information to the NTN-CN device.

[0045] In one possible implementation, before the TN-CN device sends a first non-terrestrial network air interface capability request to the user equipment UE, the method also includes: the TN-CN device receives a first capability change message sent by the UE, and the first capability change message is used to indicate that the UE's NTN air interface capability has changed.

[0046] In some examples, after receiving the first capability change message, the TN-CN device sends a first non-terrestrial network air interface capability request to the UE in response to the first capability change message.

[0047] In some examples, after receiving the first capability change message, the TN-CN device sends the first capability change message to the NTN-CN device; the TN-CN device receives the second non-terrestrial network air interface capability request sent by the NTN-CN device; and the TN-CN device responds to the second non-terrestrial network air interface capability request and sends the first non-terrestrial network air interface capability request to the UE. In this way, the NTN-CN device can respond to the first capability change message by sending the second non-terrestrial network air interface capability request to the TN-CN device, triggering the TN-CN device to obtain the UE's NTN air interface capability information.

[0048] In a sixth aspect, the present application provides a capability synchronization method, which is applied to a terrestrial wireless access network (TN-RAN) device. In one possible implementation, the method includes: the TN-RAN device sending a first non-terrestrial network air interface capability request to a user equipment (UE), the first non-terrestrial network air interface capability request being used to obtain the UE's NTN air interface capability information; the TN-RAN device receiving a first non-terrestrial network air interface capability message sent by the UE, the first non-terrestrial network air interface capability message including the UE's NTN air interface capability information; and the TN-RAN device sending a second non-terrestrial network air interface capability message to a non-terrestrial network core network (NTN-CN) device or a terrestrial network core network (TN-CN) device, the second non-terrestrial network air interface capability message including the UE's NTN air interface capability information. In this way, the TN-RAN device can help the NTN-CN device obtain the UE's NTN air interface capability information, thereby saving NTN air interface resources.

[0049] In the seventh aspect, the present application provides an electronic device comprising: one or more processors and one or more memories; the one or more memories are coupled to the one or more processors, and the one or more memories are used to store computer executable programs. When the one or more processors execute the computer executable programs, the electronic device executes any possible implementation method as described in aspects 2 to 6.

[0050] In an eighth aspect, the present application provides a computer-readable storage medium that stores a computer program. When the computer program runs on a processor of an electronic device, the electronic device executes any possible implementation method as described in aspects 2 to 6.

[0051] In a ninth aspect, the present application provides a chip, applied to a user device, comprising multiple modules, including a mobile communication module and an NTN communication module, and the multiple modules are used to execute any possible implementation method as in the second aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] FIG1 is a schematic diagram of a communication system 10 provided in an embodiment of the present application;

[0053] FIG2 is a schematic diagram of a registration call flow provided in an embodiment of the present application;

[0054] FIG3 is a schematic diagram of a process of changing UE capabilities according to an embodiment of the present application;

[0055] FIG4 is a flow chart of a capability synchronization method provided in an embodiment of the present application;

[0056] FIG5 is a flow chart of another capability synchronization method provided in an embodiment of the present application;

[0057] FIG6 is a flow chart of another capability synchronization method provided in an embodiment of the present application;

[0058] FIG7 is a flow chart of another capability synchronization method provided in an embodiment of the present application;

[0059] FIG8 is a schematic diagram of the hardware structure of a UE 100 provided in an embodiment of the present application. DETAILED DESCRIPTION

[0060] The following is a clear and detailed description of the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings. In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B; "and / or" in the text is only a description of the association relationship between related objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0061] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to imply or suggest relative importance or implicitly indicate the number of the technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of this application, unless otherwise specified, "plurality" means two or more.

[0062] First, a communication system provided by an embodiment of the present application is introduced.

[0063] Exemplarily, as shown in FIG1 , the communication system 10 may include but is not limited to core network (CN) equipment, radio access network (RAN) equipment, and user equipment UE 100. The core network equipment may be used to authenticate user equipment and provide mobile communication services (e.g., call control, data transmission, etc.) to UEs accessing the core network equipment. The core network equipment may be divided into terrestrial network core network (TN-CN) equipment and non-terrestrial network core network (NTN-CN) equipment. The NTN-CN equipment may include but is not limited to an access and mobility management function (AMF) 300. The AMF 300 may be used for NTN core network registration management, UE mobility management control, context security management, and the like.

[0064] The radio access network device may include one or more base stations (next generation node b, gNB). The radio access network device may be used for UE to access core network devices. The radio access network device may be divided into terrestrial network radio access network (TN-RAN) devices and non-terrestrial network radio access network (NTN-RAN) devices. UE100 may access TN-CN devices through TN-RAN devices, and TN-RAN devices may include the ground base station shown in Figure 1. UE100 may access NTN-CN devices through NTN-RAN devices, and NTN-RAN devices may include base station 200 shown in Figure 1. It should be noted that base station 200 may include a satellite and a ground transceiver station. When UE100 sends data to the NTN-CN device, UE100 first sends the data to the satellite of base station 200. After the satellite of base station 200 receives the data sent by UE100, it may relay the data sent by UE100 to the ground transceiver station, and the ground transceiver station may transmit the data sent by UE100 to the NTN-CN device. Similarly, when the NTN-CN device sends data to UE100, the NTN-CN device can first send the data to the ground transceiver station of the base station 200. The ground transceiver station can intermediately forward the data sent by the NTN-CN device to the satellite of the base station 200. The satellite of the base station 200 can send the data of the NTN-CN device to UE100.

[0065] TN-RAN equipment and TN-CN equipment can be collectively referred to as terrestrial network equipment, and NTN-CN equipment and NTN-RAN equipment can be collectively referred to as non-terrestrial network equipment.

[0066] In an embodiment of the present application, UE100 can send a wireless signal to the base station 200. After the base station 200 receives the wireless signal sent by UE100, it can forward the wireless signal sent by UE100 to the AMF300 on the ground. Similarly, AMF300 can send a wireless signal to the base station 200, and after the base station 200 receives the wireless signal sent by AMF300, it can forward the wireless signal to UE100. In this way, when UE100 is in an area where mobile communication is not covered, cannot be covered, or the communication system is damaged, such as the ocean, desert, grassland, or uninhabited area, UE100 cannot receive the signal from the ground network, and can access the core network of the non-ground network through the satellite base station, and perform positioning and communication through the core network of the non-ground network.

[0067] The transmission protocol of the communication system 10 includes an access stratum (AS) protocol and a non-access stratum (NAS) protocol. In the communication system 10, the UE 100 and the AMF 300 can communicate via the NAS protocol, the UE 100 and the base station 200 can communicate via the AS protocol, and the AMF 300 and the base station 200 can also communicate via the AS protocol. The AS protocol layer may include a physical (PHY) layer, a medium access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, and a radio resource control (RRC) layer.

[0068] In the following description, NTN-CN equipment may be abbreviated as NTN-CN, TN-CN equipment may be abbreviated as TN-CN, NTN-RAN equipment may be abbreviated as NTN-RAN, and TN-RAN equipment may be abbreviated as TN-RAN.

[0069] In one possible implementation, after UE 100 finds NTN-RAN, it performs a registration process with NTN-CN. During the registration process, NTN-CN can obtain the UE's NTN air interface capability information from NTN-RAN. Specifically, the registration process for UE 100 with NTN-CN can refer to the embodiment shown in FIG2 . Stage 7 in FIG2 details the process by which NTN-CN obtains the UE 100's NTN air interface capability information. As shown in FIG2 , the NTN registration call process includes the following steps:

[0070] Phase 1: Downlink Synchronization (DL Sync)

[0071] S201 . UE 100 receives a master information block (MIB) sent by base station 200 .

[0072] Base station 200 can broadcast the MIB, and any UE within the beam range of base station 200 can receive the MIB sent by base station 200. The MIB includes demodulation parameters of system information block type 1 (SIB1), system bandwidth, system frame number, etc. Based on the MIB, UE 100 can adjust its receiving frequency range to the frequency range for receiving downlink signals from base station 200. UE 100 can also adjust the time point for receiving communication frames sent by base station 200 based on the MIB.

[0073] S202 . UE 100 receives SIB1 sent by base station 200 .

[0074] SIB1, also known as remaining minimum system information (RMSI), can be broadcast by base station 200. UE 100 can obtain the contents of SIB1 broadcast by base station 200 according to the demodulation parameters indicated by the MIB. SIB1 can also include reception time parameters for other SIB messages, indicating the time point at which UE 100 receives other SIB messages.

[0075] In this way, after executing the steps of phase 1, UE 100 can achieve downlink synchronization between UE 100 and base station 200 , and UE 100 can receive data sent by base station 200 within the frequency band indicated by base station 200 and at the time indicated by base station 200 .

[0076] Phase 2: Uplink Synchronization (UL Sync)

[0077] S203 . UE 100 sends message 1 (message 1 , MSG 1 ) to base station 200 .

[0078] Message 1 is the preamble sequence of the 3rd Generation Partnership Project (3GPP) uplink synchronization process. UE 100 can obtain random access channel (RACH) configuration information based on SIB1 and select a preamble sequence corresponding to the configuration information based on the obtained configuration information. UE 100 can achieve uplink synchronization between UE 100 and base station 200 based on the preamble sequence, and UE 100 can send uplink signals to base station 200. Message 1 can be referred to as a random access channel preamble sequence (RACH Preamble).

[0079] S204 . UE 100 receives message 2 (message 2, MSG2) sent by base station 200 .

[0080] After receiving MSG1 sent by UE100, base station 200 can determine the transmission delay between base station 200 and UE100 based on MSG1. Thereafter, base station 200 can determine the value of the timing advance command (TAM) field based on the transmission delay between base station 200 and UE100. The timing advance command field is a field in MSG2, which is used to indicate the time when UE100 sends uplink data. Base station 200 can send MSG2 including the TAM field to UE100. After receiving MSG2, UE100 can determine the time to send uplink data to base station 200. Message 2 can be called a random access channel response (RACH Response).

[0081] In this way, after executing the steps of phase 2, UE 100 can achieve uplink synchronization between UE 100 and base station 200 , and UE 100 can send data to base station 200 within the frequency band indicated by base station 200 and at the time indicated by base station 200 .

[0082] Phase 3: Signaling Radio Bearers 0 (SRB0)

[0083] S205 . UE 100 sends message 3 (message 3, MSG3) to base station 200 .

[0084] After receiving MSG2, UE 100 may establish an RRC connection with base station 200. UE 100 may transmit NAS layer data via the RRC connection. Based on the time indicated by MSG2 for sending uplink data, UE 100 may send MSG3, an RRC Setup Request, to base station 200 via SRB0 on ​​the uplink common control channel (UL-CCCH). SRB0 may be used to carry RRC message MSG3.

[0085] S206 . UE 100 receives message 4 (message 4 , MSG4 ) sent by base station 200 .

[0086] The base station 200 can receive MSG3 from the UE 100 at the time indicated by MSG2. After receiving MSG3, the base station 200 can determine whether to allow the establishment of the RRC connection and set the content of MSG4 according to the determination result. Among them, when the base station 200 does not allow the establishment of the RRC connection, the message 4 is a radio resource control reject (RRC Reject) message. When the base station 200 confirms the establishment of the RRC connection, the message 4 is a radio resource control establishment (RRC Setup) message. The base station 200 can also carry the complete configuration of SRB1 in the RRC Setup message, and the base station 200 can send the MSG4 through SRB0. After receiving the RRC Setup message, the UE 100 can establish SRB1 based on the message.

[0087] In this way, UE 100 can establish an RRC connection after executing the steps of phase three.

[0088] Phase 4: Signaling Radio Bearers 1 (SRB1)

[0089] S207 . UE 100 sends a radio resource control connection setup complete (RRC Setup Complete) message and a non-access stratum registration message (NAS Registration) to the base station 200 .

[0090] After receiving MSG4, UE 100 may configure SRB1 based on MSG4. After completing SRB1 configuration, UE 100 may send an RRC Setup Complete message to base station 200, confirming that the RRC connection has been successfully established. After receiving the RRC Setup Complete message, base station 200 may select an AMF. Here, the AMF selected by base station 200 is AMF 300 shown in Figure 1 .

[0091] The RRC Setup Complete message carries a non-access layer registration message, which can be used for UE 100 to register with the AMF. The RRC Setup Complete message sent by UE 100 to base station 200 is carried on SRB1.

[0092] In this way, in the fourth stage, UE100 can send a NAS message to the base station 200 through SRB1, and the base station 200 can forward the NAS message of UE100 to AMF300.

[0093] Phase 5: Registration Request

[0094] S208. The base station 200 sends the initial user equipment information (Initial UE Message) and registration request (registration request) message of the NG application protocol (NGAP) to the AMF300.

[0095] Among them, NGAP can provide signaling services to RAN nodes and AMF nodes, and can provide signaling and data connections for UE to access the core network. After the base station 200 selects AMF300, it can send an Initial UE Message to AMF300. This message can be used to notify AMF300 that the UE100 will access the core network. The message includes the radio access network user equipment identity (RAN UE NGAP ID) assigned by the base station 200 to UE100 in the NG application protocol. AMF300 can transmit NAS messages with UE100 through the RAN UE NGAP ID. Among them, the base station 200 can send the NAS message (i.e., registration request message) carried in the RRC Setup Complete message to AMF300 through the Initial UE Message, and the registration request message can be used to notify AMF300 that the UE100 registers with the core network.

[0096] Phase 6: NAS Procedure Identity, Authentication (AUTH), and Security Mode Command (SMC)

[0097] S209.AMF300 sends an NGAP non-access layer identity request (NAS Identity Request) message to the base station 200.

[0098] Among them, the non-access layer identity request is used by the AMF300 of the core network to obtain the identity of UE100.

[0099] S210 . The base station 200 sends a non-access stratum identity request message to the UE 100 .

[0100] After receiving the NAS message sent by AMF300, base station 200 can forward the NAS message to UE100.

[0101] S211 . UE 100 sends a non-access stratum identity response (NAS Identity Response) message to base station 200 .

[0102] After receiving the NAS message from AMF 300, UE 100 may generate an identity response message that carries the identity indicated in the identity request message. For example, the identity may be an international mobile subscriber identity (IMSI). UE 100 may send the identity response message to base station 200.

[0103] S212. The base station 200 sends an NGAP non-access layer identity response message to the AMF 300.

[0104] After receiving the NAS message sent by UE100, base station 200 may forward the NAS message to AMF300. After AMF300 receives the identity response message from UE100, it may perform step S213 based on the identity identifier of UE100 carried in the identity response message.

[0105] S213.AMF300 sends an NGAP non-access layer authentication request (NAS Authentication Request) message to the base station 200.

[0106] After receiving the identity identification parameters, the AMF 300 may generate authentication parameters to be carried in the non-access stratum authentication request message. The authentication parameters may include, but are not limited to, a random number (RAND) generated by the AMF 300 using a random number generator and an authentication token (AUTN). The AMF 300 may send the non-access stratum authentication request message to the base station 200.

[0107] S214 . The base station 200 sends a non-access stratum authentication request message to the UE 100 .

[0108] S215 . UE 100 sends a non-access stratum authentication response (NAS Authentication Response) message to base station 200 .

[0109] After receiving the NAS authentication request message sent by AMF300 through base station 200, UE100 can calculate the response (RES) of UE100 based on the RAND and AUTN in the authentication parameters. UE100 can send a non-access layer authentication response message carrying RES to base station 200.

[0110] S216. The base station 200 sends an NGAP non-access layer authentication response message to the AMF 300.

[0111] After receiving the non-access layer authentication response message from UE100 through base station 200, AMF300 can authenticate whether UE100 is a legitimate terminal based on RES. When AMF300 confirms that UE100 is a legitimate terminal (i.e., AMF300 authentication is successful), AMF300 can provide communication services to UE100.

[0112] S217.AMF300 sends an NGAP non-access layer security mode command (NAS Security Mode Command) message to the base station 200.

[0113] The non-access stratum security mode command message may be used to notify the UE 100 to start integrity protection and data encryption.

[0114] S218 . The base station 200 sends a non-access stratum security mode command message to the UE 100 .

[0115] S219 . UE 100 sends a NAS Security Mode Complete message to base station 200 .

[0116] UE 100 may determine the integrity protection and encryption algorithms based on the non-access stratum security mode command message. UE 100 may encrypt the NAS message based on the integrity protection and encryption algorithms. After receiving the non-access stratum security mode command message, UE 100 may also send a non-access stratum security mode complete message to base station 200, indicating that UE 100 has completed the security mode configuration.

[0117] S220. The base station 200 sends an NGAP non-access layer security mode completion message to the AMF 300.

[0118] The AMF 300 may receive a non-access stratum security mode completion message from the UE 100 through the base station 200 and determine that the UE 100 encrypts the NAS message according to the agreed encryption algorithm.

[0119] S221.AMF300 sends an NGAP initial context setup request message and a registration accept message to the base station.

[0120] AMF 300 may send an Initial Context Setup Request message to base station 200 to initiate the initial context establishment process. This message includes a Registration Accept message, which is a NAS message.

[0121] In this way, in the sixth stage, UE100 and UE AMF300 can transparently transmit NAS messages through base station 200 to complete identity query, authentication, setting of NAS security mode and UE100 registration process.

[0122] Phase 7: UE Capability Exchange

[0123] S222 . The base station 200 sends a UE Capability Enquiry message to the UE 100 .

[0124] After receiving the initial context setup request message sent by AMF300, base station 200 can send a user equipment capability query message to UE100 to start the UE100 capability query process. After obtaining the capabilities of UE100, base station 200 can provide UE100 with the resources required by UE100.

[0125] It should be noted that if the initial context setup request message includes an information element (IE) carrying the user equipment radio capability (UE Radio Capability) of UE100, it indicates that AMF300 has stored the NTN air interface capability information of UE100, and the base station 200 does not perform step S222. If the initial context setup request message does not include the IE carrying the UE Radio Capability of UE100, the base station 200 can obtain the NTN air interface capability information of UE100 through stage seven and send the NTN air interface capability information of UE100 to AMF300. It should also be noted that when UE100 performs the NTN registration process or changes capabilities, the initial context setup request message sent by AMF300 does not include the IE carrying the UE Radio Capability of UE100.

[0126] S223 . UE 100 sends a user equipment air interface capability information (UE Capability Information) message to base station 200 .

[0127] UE 100 replies to base station 200 with a UE Capability Information message, which may carry the NTN air interface capability information of UE 100 and is used by UE 100 to report the NTN air interface capability information of UE 100 to base station 200. For example, the NTN air interface capability information of UE 100 may indicate the carriers (bands) supported by UE 100, the user equipment class (UE Category) of UE 100, the antenna polarization direction of UE 100, the maximum transmit power (power level) of UE 100, the duplex mode of UE 100, and so on.

[0128] S224. The base station 200 sends an NGAP user equipment air interface capability information indication (UE Capability Info Indication) message to the AMF 300.

[0129] The base station 200 may send a UE Capability Info Indication message to the AMF 300. The message may carry the NTN air interface capability information of the UE 100, and is used by the base station 200 to report the NTN air interface capability information of the UE 100 to the AMF 300. The AMF 300 may save the received NTN air interface capability information of the UE 100.

[0130] In this way, in the seventh stage, both AMF300 and base station 200 obtain the NTN air interface capability information of UE100. AMF300 and base station 200 can configure air interface resources and communication methods for UE100 based on the NTN air interface capability information of UE100.

[0131] Stage 8: Access stratum security mode command (AS SMC)

[0132] S225 . The base station 200 sends an access layer security mode command message to the UE 100 .

[0133] After reporting the capabilities of UE 100 to AMF 300, base station 200 may send an access stratum security mode command message to UE 100, instructing UE 100 to perform integrity protection and encryption on data, allowing secure transmission of RRC messages between UE 100 and base station 200. The access stratum security mode command message may indicate the security key, integrity key, encryption algorithm, and integrity protection algorithm to be used when transmitting messages between UE 100 and base station 200. After sending the access stratum security mode command message, base station 200 may encrypt data and set integrity protection for the data when sending it to UE 100, and then send the encrypted and integrity-protected data to UE 100.

[0134] S226 . UE 100 sends an access layer security mode complete (AS Security Mode Complete) message to base station 200 .

[0135] After receiving the access stratum security mode command message sent by base station 200, UE 100 may send an access stratum security mode complete message to base station 200. This access stratum security mode complete message has been integrity protected. After sending the access stratum security mode complete message to base station 200, UE 100 may initiate security mode. In security mode, UE 100 will integrity protect and encrypt data using an algorithm agreed upon with base station 200, and then send the integrity-protected and encrypted data to base station 200.

[0136] In this way, after the eighth stage, the UE 100 and the base station 200 can encrypt and protect the transmitted data through the agreed key, thereby ensuring the security of data transmission.

[0137] Phase 9: Signaling Radio Bearers 2 (SRB2) and Data Radio Bearers (DRB)

[0138] S227. The base station 200 sends a radio resource control connection reconfiguration (RRC Connection Reconfiguration) message and a registration acceptance message to the UE 100.

[0139] The base station 200 sends an RRC Connection Reconfiguration message to the UE 100. The RRC Connection Reconfiguration message includes the registration acceptance message sent by the AMF and parameters for establishing a radio bearer.

[0140] S228. UE 100 sends a radio resource control connection reconfiguration complete (RRC Connection Reconfiguration Complete) message to base station 200.

[0141] After receiving the RRC Connection Reconfiguration message, UE 100 begins to establish SRB2 and DRB. After successful establishment, UE 100 can reply to base station 200 with an RRC Connection Reconfiguration Complete message. DRB can be used to transmit UE 100 data, such as Transmission Control Protocol (TCP) / Internet Protocol (IP) data packets.

[0142] S229. The base station 200 sends an initial context setup response message of NGAP to the AMF 300.

[0143] After receiving the RRC Connection Reconfiguration Complete message, the base station 200 can send an initial context setup response message to the AMF300.

[0144] Stage 10: Registration Complete

[0145] S230 . UE 100 sends a registration complete message to base station 200 .

[0146] S231. The base station 200 sends an NGAP registration completion message to the AMF 300.

[0147] Base station 200 sends the registration completion message of UE100 to AMF300, and UE100 successfully registers with the core network.

[0148] In this way, after the above ten steps, UE100 successfully registers with the core network, and can send service data to AMF300 through base station 200, and can also receive service data from AMF300 through base station 200.

[0149] Phase 11: Protocol Data Unit Session (PDU Session)

[0150] S232 . UE 100 sends a protocol data unit session establishment request (PDU Session Establishment Request) message to base station 200 .

[0151] Among them, the PDU Session Establishment Request message is a NAS message.

[0152] S233. The base station 200 sends an NGAP protocol data unit session establishment request message to the AMF300.

[0153] S234.AMF300 sends an NGAP protocol data unit session establishment accept (PDU Session Establishment Accept) message to the base station 200.

[0154] After receiving the protocol data unit session establishment request message from the UE 100 through the base station 200 , the AMF 300 may allocate resources for the PDU session connection to the UE 100 and send a protocol data unit session establishment accept message to the UE 100 through the base station 200 .

[0155] S235 . The base station 200 sends a protocol data unit session establishment accept message to the UE 100 .

[0156] UE100 establishes a PDU session connection with AMF300, and PDU messages can be transmitted through this connection.

[0157] Thus, through steps S222 to S224, both base station 200 and AMF 300 obtain the NTN air interface capability information of UE 100. The distance between UE 100 and base station 200 is relatively long. To prevent the base station 200 from being unable to transmit data to UE 100, the bandwidth used by base station 200 for data transmission is relatively narrow, resulting in a relatively small amount of data transmitted per unit time between UE 100 and base station 200. Furthermore, the UE's NTN air interface capability information occupies a significant amount of air interface resources, resulting in poor channel quality between UE 100 and base station 200. Therefore, the transmission of the UE's NTN air interface capability information between UE 100 and base station 200 requires a longer time. Furthermore, because the UE 100 consumes a lot of power when transmitting or receiving satellite signals, the UE 100 consumes even more power to transmit the NTN air interface capability information to base station 200.

[0158] In one possible implementation, after a capability change occurs, UE 100 may send a notification message to the NTN-RAN indicating an update of UE 100's NTN air interface capability information. Upon receiving this notification message, NTN-RAN may notify NTN-CN to delete the stored NTN air interface capability information of UE 100. NTN-RAN may also obtain updated NTN air interface capability information from UE 100 and send the updated NTN air interface capability information to NTN-CN. In this way, UE 100 may notify NTN-RAN of a capability change. Upon receiving the UE 100 capability change message, NTN-RAN may reacquire UE 100's NTN air interface capability information and update the NTN air interface capability information stored by NTN-RAN and NTN-CN.

[0159] In some examples, the state of UE 100 may include a connected state, an idle state, and an inactive state. If UE 100 is in a connected state, UE 100 may release the local connected state after the capability change, and then update the NTN air interface capability information of UE 100 stored in base station 200 and AMF 300. If UE 100 is not in a connected state, UE 100 may directly update the NTN air interface capability information of UE 100 stored in base station 200 and AMF 300. UE 100 may update the NTN air interface capability information without releasing the connected state.

[0160] In some examples, after the capability is changed, UE 100 may send a registration request message with a registration type of mobility registration update to AMF 300, where the registration request message includes parameters indicating the capability change of UE 100. After receiving the registration request message, AMF 300 may delete the invalid NTN air interface capability information of UE 100 and trigger base station 200 to re-acquire the updated NTN air interface capability information of UE 100.

[0161] For example, as shown in FIG3 , the UE 100 capability change process includes the following steps:

[0162] S301. UE100 capability changes.

[0163] S302. UE100 determines whether it is in a connected state.

[0164] After UE 100's capabilities are changed, UE 100 may initiate a process to update UE 100's NTN air interface capability information stored on the NTN. First, after the capabilities are changed, UE 100 may determine whether UE 100 is in a connected state. If UE 100 determines that UE 100 is in a connected state, step S303 may be executed. If UE 100 determines that UE 100 is not in a connected state, step S304 may be executed.

[0165] S303. UE 100 releases the connection state.

[0166] After determining that the UE 100 is in the connected state, the UE 100 may release the local connected state and switch to the non-connected state (eg, idle state). After releasing the local connected state, the UE 100 may execute step S304 to notify the base station 200 to update the NTN air interface capability information of the UE 100.

[0167] S304. UE 100 sends a registration request message to base station 200, including parameters indicating that the NTN air interface capability of UE 100 has changed.

[0168] After releasing the locally connected state, UE 100 may send a registration request message to base station 200. This registration request message may include parameters indicating a change in UE 100's NTN air interface capabilities. The types of registration request messages sent by UE 100 include initial registration, mobility registration, and periodic registration. Here, UE 100 initiates a registration request message of the mobility registration type to update the UE 100's NTN air interface capability information stored in base station 200 and AMF 300.

[0169] For example, the registration request message may include a Next Generation Radio Access Network (NG-RAN) Radio Capability Update field. The NG-RAN Radio Capability Update field may be used to indicate whether the NTN air interface capabilities of UE 100 have changed. When the value of this field is 1, it indicates that the NTN air interface capabilities of UE 100 have changed. When the value of this field is 0, it indicates that the NTN air interface capabilities of UE 100 have not changed. In this case, the value of this field in the registration request message is 1.

[0170] S305. The base station 200 sends a UE Capability Release Command message to the AMF 300.

[0171] After receiving the parameter sent by UE100 to indicate the capability change of UE100, base station 200 may send a user equipment capability release command message to AMF300. After receiving the user equipment capability release command message, AMF3000 may delete the stored NTN air interface capability information of UE100.

[0172] S306 . The base station 200 sends a user equipment capability query message to the UE 100 .

[0173] S307 . UE 100 sends a user equipment air interface capability information message to base station 200 .

[0174] S308. The base station 200 sends an NGAP user equipment air interface capability information indication message to the AMF300.

[0175] After receiving the NTN air interface capability information of the UE 100, the AMF 300 may store the NTN air interface capability information of the UE 100. Specifically, the description of steps S306 to S308 can refer to the description of stage 7 in the embodiment shown in FIG2 , and will not be repeated here.

[0176] S309. UE 100 switches to connected state.

[0177] UE 100 can switch to the connected state after updating the NTN air interface capability information of UE 100 stored on the NTN side. It should be noted that when UE 100 releases the connected state, UE 100 releases the RRC connection with base station 200 and remains registered with AMF 300. After that, UE 100 sends the updated NTN air interface capability information to base station 200 and can switch back to the connected state to restore the RRC connection with base station 200.

[0178] In this way, when the capability of UE 100 changes, UE 100 can synchronize the NTN air interface capability information of UE 100 through the process shown in FIG. 3 .

[0179] An embodiment of the present application provides a capability synchronization method. UE100 includes an NTN communication module and a mobile communication module, the mobile communication module is bound to a subscriber identification module (SIM) 1, and the NTN communication module is bound to a SIM2. UE100 can access a terrestrial network through the mobile communication module. UE100 can access a non-terrestrial network through the NTN communication module. After the mobile communication module is registered with the core network of the terrestrial network, the NTN communication module can execute the registration process of the core network of the non-terrestrial network through the mobile communication module, the wireless access network of the terrestrial network, and the core network of the terrestrial network. After executing the registration process, the NTN communication module can also send the UE's NTN air interface capability information to the core network of the non-terrestrial network through the mobile communication module and the core network of the terrestrial network.

[0180] In this way, the NTN communication module of UE 100 can access the core network of the non-terrestrial network after receiving the NTN signal. Because UE 100 has already sent its NTN air interface capability information to the core network of the non-terrestrial network in the terrestrial network, and the core network of the non-terrestrial network stores the NTN air interface capability information of UE 100, UE 100 does not need to transmit the NTN air interface capability information to the core network of the non-terrestrial network in the non-terrestrial network. This reduces the signaling overhead between UE 100 and the core network of the non-terrestrial network, saves the time required for UE 100 to transmit the NTN air interface capability information in the non-terrestrial network, and saves power consumption of UE 100.

[0181] It should be noted that the binding of the NTN communication module and the mobile communication module of UE100 with the SIM is only an example. The NTN communication module and the mobile communication module of UE100 can also be bound to an embedded subscriber identification module (eSIM), which is not limited in this embodiment of the present application.

[0182] For example, as shown in FIG4 , the capability synchronization method provided in an embodiment of the present application includes the following steps:

[0183] S401 . The mobile communication module of UE 100 receives a non-terrestrial network registration request message 31 from the NTN communication module of UE 100 .

[0184] Before initiating TN registration, the mobile communication module can receive registration request information from the NTN communication module. For example, data can be transmitted between the mobile communication module and the NTN communication module via the NAS layer protocol, and the mobile communication module can obtain the non-terrestrial network registration request message 31 from the NTN communication module via the NAS layer protocol. This non-terrestrial network registration request message 31 can be used to trigger the NTN-CN to initiate a registration process. The registration type of the non-terrestrial network registration request message 31 is initial registration. After powering on, the NTN communication module of UE 100 has not registered with the NTN-CN and initiates an initial registration request. For example, this non-terrestrial network registration request message 31 can be represented as NTN registration request (initial registration).

[0185] The NTN communication module may send the registration request message to the mobile communication module after powering on. Alternatively, the mobile communication module may receive the registration request message from the NTN communication module after powering on. Alternatively, the mobile communication module may receive the registration request message from the NTN communication module before initiating TN registration. Alternatively, the mobile communication module may receive the registration request message after successfully registering the TN-CN device.

[0186] S402. The mobile communication module registers with the TN-CN through the TN-RAN.

[0187] After powering on, UE 100 can register with the TN-CN. The mobile communication module performs network registration operations with the TN-CN. A detailed description of how the mobile communication module registers with the TN-CN via the TN-RAN can be found in the example of UE 100 registering with the NTN-CN via the NTN-RAN shown in FIG2 , and will not be repeated here. The mobile communication module successfully registers with the TN-CN.

[0188] Optionally, the mobile communication module may obtain the registration request message 31 of the NTN communication module after successfully registering with the TN-CN.

[0189] S403. The mobile communication module sends a non-access stratum message (NAS message) 32 to the TN-CN through the TN-RAN. The non-access stratum message 32 includes an N1 non-terrestrial network container (N1 interface non-terrestrial network container, N1 NTN Container) 33. The N1 NTN Container 33 includes a non-terrestrial network registration request message 31.

[0190] The N1 interface is the communication interface between the UE 100 and the AMF 300 of the NTN, and the N1 NTN Container can be used to carry data sent by the UE 100 to the AMF 300. For example, the non-access stratum message 32 can be expressed as a NAS message (N1 NTN Container (NTN registration request (initial registration))).

[0191] S404. TN-CN sends N1 NTN Container 33 to NTN-CN.

[0192] The TN-CN can send the N1 NTN Container 33 to the NTN-CN based on SIM2's NTN subscription information, such as the public land mobile network (PLMN) of SIM2's NTN. Specifically, the TN-CN's AMF can send the N1 NTN Container 33 to the NTN-CN's AMF 300. The TN-CN includes a subscription server that can provide NTN subscription services. SIM2 can obtain the NTN subscription services from the TN-CN's operator. The TN-CN's AMF can obtain SIM2's NTN subscription information from the TN-CN subscription server.

[0193] S405. NTN-CN obtains the identity of the NTN communication module.

[0194] The NTN-CN's AMF 300 can obtain the identity of the NTN communication module through the TN-CN, TN-RAN, and mobile communication module. Here, the identity of the NTN communication module is the SIM2 identifier, for example, the subscriber concealed identifier (SUCI). The AMF 300 can determine the identity of the NTN communication module based on the SUCI.

[0195] For example, the NTN-CN may send an N1 NTN Container including a non-terrestrial network identity request message to the TN-CN. The non-terrestrial network identity request message is used to obtain the identity of the NTN communication module of UE 100. The TN-CN sends a non-access stratum message including the N1 NTN Container to the mobile communication module of UE 100 via the TN-RAN. The mobile communication module of UE 100 sends the non-terrestrial network identity request message to the NTN communication module of UE 100.

[0196] After receiving the non-terrestrial network identity request message, the NTN communication module can generate a non-terrestrial network identity response message (NTN identity response) based on the NTN communication module's identity and send the non-terrestrial network identity response message to the mobile communication module. The mobile communication module sends a non-access stratum message to the TN-CN via the TN-RAN. The non-access stratum message includes an N1 NTN container, which includes the non-terrestrial network identity response message. The TN-CN sends the N1 NTN container including the non-terrestrial network identity response message to the NTN-CN. In this way, the NTN-CN obtains the identity of the NTN communication module of UE 100 through the TN-CN, TN-RAN, and the mobile communication module.

[0197] S406. NTN-CN authenticates SIM2 bound to the NTN communication module.

[0198] Authentication signaling can be transmitted between NTN-CN and NTN communication module through TN-CN, TN-RAN and mobile communication module to realize NTN-CN's AMF300 to authenticate SIM2 of UE100.

[0199] For example, after receiving the identity of the NTN communication module, the NTN-CN can authenticate the NTN communication module. The NTN-CN can send an N1 NTN Container including a non-terrestrial network authentication request message to the TN-CN. The non-terrestrial network authentication request message is used to authenticate SIM2 bound to the NTN communication module of UE 100. The TN-CN sends a non-access stratum message including the N1 NTN Container to the mobile communication module of UE 100 via the TN-RAN. The mobile communication module of UE 100 sends the non-terrestrial network authentication request message to the NTN communication module of UE 100.

[0200] After receiving the non-terrestrial network authentication request message, the NTN communication module can calculate an authentication response by combining the authentication parameters of SIM2 and the authentication parameters of the non-terrestrial network authentication request message through an authentication algorithm. Based on the authentication response, it generates a non-terrestrial network authentication response message (NTN authentication response). The NTN communication module sends this non-terrestrial network authentication response message to the mobile communication module. The mobile communication module sends a non-access stratum message to the TN-CN via the TN-RAN. This non-access stratum message includes an N1 NTN container, which contains the non-terrestrial network authentication response message. The TN-CN sends the N1 NTN container containing the non-terrestrial network authentication response message to the NTN-CN. Based on the authentication response in the non-terrestrial network authentication response message, the NTN-CN can determine whether the UE 100 is authenticated. In this case, the NTN-CN authenticates the UE 100. In this way, the NTN-CN authenticates the SIM2 bound to the NTN communication module of the UE 100 through the TN-CN, TN-RAN, and the mobile communication module.

[0201] S407. NTN-CN notifies the NTN communication module to configure the security mode.

[0202] NTN-CN and NTN communication module can transmit security mode command signaling through TN-CN, TN-RAN and mobile communication module to realize the security mode command operation of NTN-CN's AMF300 on UE100. UE100 and AMF300 can use the agreed encryption algorithm and integrity algorithm to ensure the security of transmitted data.

[0203] For example, after successfully authenticating SIM2 bound to the NTN communication module, the NTN-CN may notify UE 100 to configure security mode. The NTN-CN may send an N1 NTN Container including a non-terrestrial network security mode command message to the TN-CN. The non-terrestrial network security mode command message is used to notify the NTN communication module of UE 100 to configure security mode. The TN-CN sends a non-access stratum message including the N1 NTN Container to the mobile communication module of UE 100 via the TN-RAN. The mobile communication module of UE 100 sends the non-terrestrial network security mode command message to the NTN communication module of UE 100.

[0204] After receiving the non-terrestrial network security mode command message, the NTN communication module can determine the encryption algorithm and integrity algorithm. UE100 can then process the uplink data sent to NTN-CN using the obtained encryption algorithm and integrity algorithm. The NTN communication module can also generate a non-terrestrial network security mode complete message after receiving the non-terrestrial network security mode command message and send the non-terrestrial network security mode complete message to the mobile communication module. The mobile communication module sends a non-access stratum message to the TN-CN via the TN-RAN. The non-access stratum message includes an N1 NTN Container, which includes a non-terrestrial network security mode complete message. The TN-CN sends the N1 NTN Container including the non-terrestrial network security mode complete message to the NTN-CN. Based on the non-terrestrial network security mode complete message, the NTN-CN can determine that the UE100 has completed the security mode configuration. In this way, the NTN-CN notifies the UE100's NTN communication module of the security mode configuration through the TN-CN, TN-RAN, and the mobile communication module.

[0205] S408. NTN-CN sends an N1 NTN Container 36 including a non-terrestrial network registration accept message (NTN registration accept) 34 and a non-terrestrial network air interface capability request 35 to TN-CN.

[0206] After the UE 100 passes identity authentication, authentication succeeds, and security mode configuration is successfully performed, the NTN-CN may send a non-terrestrial network registration acceptance message 34 to the TN-CN. The non-terrestrial network registration acceptance message 34 may indicate that the AMF 300 of the NTN-CN accepts the registration request of the UE 100.

[0207] The NTN-CN may also send a non-terrestrial network air interface capability request 35 to the TN-CN. The non-terrestrial network air interface capability request 35 may be used to obtain NTN air interface capability information of the NTN communication module of the UE 100 when operating independently.

[0208] The NTN-CN can add the non-terrestrial network registration acceptance message 34 and the non-terrestrial network air interface capability request 35 to an N1 NTN container 36 and then send the N1 NTN container 36 to the TN-CN. In some examples, the NTN-CN and the TN-CN can communicate via the N14 interface. Here, the NTN-CN sends the N1 NTN container 36 to the TN-CN via the N14 interface.

[0209] In other examples, when registering with the TN-CN, UE 100 may include a non-terrestrial network registration request message 31 in the registration request message used to register with the TN-CN. During the TN-CN registration process, UE 100 may perform steps S405 to S407. When the TN-CN sends a registration accept message to UE 100 indicating that the TN-CN registration has been approved, the TN-CN may also include a non-terrestrial network registration accept message 34. In this way, during the TN-CN registration process, UE 100 can perform the NTN-CN registration steps through the TN-RAN and the TN-CN, thereby conserving TN network air interface resources.

[0210] S409 . The TN-CN sends a non-access stratum message 37 to the mobile communication module of the UE 100 via the TN-RAN. The non-access stratum message 37 includes an N1 NTN Container 38 , and the N1 NTN Container 38 includes the non-terrestrial network registration accept message 34 .

[0211] The TN-CN can parse N1 NTN Container 36 to obtain a non-terrestrial network registration acceptance message 34 and a non-terrestrial network air interface capability request 35. The TN-CN can encapsulate the non-terrestrial network registration acceptance message 34 into an N1 NTN Container 38, and then encapsulate the N1 NTN Container 38 into a non-access stratum message 37. The TN-CN can send the non-access stratum message 37 to the TN-RAN. The TN-RAN can send the non-access stratum message 37 to the mobile communication module.

[0212] S410. The mobile communication module sends the non-terrestrial network registration acceptance message 34 to the NTN communication module.

[0213] After receiving the non-access stratum message 37, the mobile communication module can obtain the non-terrestrial network registration acceptance message 34 from the non-access stratum message 37 and send the non-terrestrial network registration acceptance message 34 to the NTN communication module. The NTN communication module receives the non-terrestrial network registration acceptance message 34 and determines that the UE 100 has successfully registered with the NTN-CN.

[0214] In other examples, the mobile communication module can execute the process of registering the NTN communication module with a non-terrestrial network during the process of registering with the terrestrial network. Specifically, when the mobile communication module sends a registration request message for the terrestrial network to the TN-CN, it can send the NTN communication module's registration request message for the non-terrestrial network to the TN-CN. The TN-CN can then send the NTN communication module's registration request message for the non-terrestrial network to the NTN-CN. When the TN-CN sends a registration completion message for the terrestrial network to the mobile communication module, it can send the NTN-CN's registration completion message for the non-terrestrial network to the mobile communication module. The mobile communication module can then send the non-terrestrial network registration completion message to the NTN communication module. In this way, when the mobile communication module sends signaling to the TN-CN to register with the core network of the terrestrial network, it can carry signaling for registering with the NTN communication module with the core network of the non-terrestrial network, saving signaling overhead. During the process of registering with the terrestrial network, the NTN communication module can register with the non-terrestrial network through the mobile communication module and the TN-CN, and the NTN-CN can obtain the registration information of the NTN communication module. After UE100 searches for a wireless access network device on a non-terrestrial network, the NTN communication module can register with the non-terrestrial network without having to perform tedious identity authentication, authorization, and security mode command processes, saving time in network registration and reducing the power consumption of UE100 in sending and receiving satellite data.

[0215] S411 . The TN-CN sends a radio resource control layer message 39 to the mobile communication module of the UE 100 via the TN-RAN. The radio resource control layer message 39 includes a non-terrestrial network air interface capability request 35 .

[0216] The TN-CN may encapsulate the non-terrestrial network air interface capability request 35 to obtain a radio resource control message 39 and then send the radio resource control message 39 to the TN-RAN. The TN-RAN may forward the radio resource control message 39 to the mobile communication module of the UE 100 .

[0217] In other examples, the TN-CN may place the non-terrestrial network air interface capability request 35 in an N1 NTN container, encapsulate the N1 NTN container to obtain a radio resource control message 39, and send the radio resource control message 39 to the TN-RAN. The TN-RAN may forward the radio resource control message 39 to the mobile communication module of UE 100. Alternatively, the TN-CN may encapsulate the N1 NTN container to obtain a non-access stratum message, and send the non-access stratum message to the TN-RAN. The TN-RAN may forward the non-access stratum message to the mobile communication module of UE 100.

[0218] In other examples, the NTN-CN may send a non-terrestrial network air interface capability information request message (NTN capability info request) to the TN-CN. The TN-CN may forward the message to the TN-RAN. After receiving the message, the TN-RAN may send a user equipment capability query message to the NTN communication module via the mobile communication module.

[0219] For example, the TN-CN may forward the non-terrestrial network air interface capability information request message to the TN-RAN via NGAP. The TN-RAN may generate a user equipment capability query message based on the non-terrestrial network air interface capability information request message. The TN-RAN may add the user equipment capability query message to an RRC message and send the RRC message to UE 100. For example, the RRC message includes an N1 NTN container, which includes the user equipment capability query message. The user equipment capability query message includes parameters for instructing UE 100 to send NTN air interface capability information to the TN-RAN. For example, the user equipment capability query message may be UE capability enquiry (NTN).

[0220] In other examples, the NTN-CN may send a non-terrestrial network air interface capability information request message to the TN-CN. After receiving the message, the TN-CN may send a user equipment capability query message to the TN-RAN. The TN-RAN may send the user equipment capability query message to the mobile communication module. After receiving the message, the mobile communication module may execute step S412.

[0221] S412. The mobile communication module obtains the air interface capability information of the NTN communication module operating independently.

[0222] After receiving the non-terrestrial network air interface capability request 35, the mobile communication module can obtain the air interface capability information of the NTN communication module when operating independently from the NTN communication module. The air interface capability information of the NTN communication module when operating independently can be referred to as NTN air interface capability information. The NTN air interface capability information may include, but is not limited to, the carriers (bands) supported by the UE 100, the user equipment category (UE Category) of the UE 100, the antenna polarization direction of the UE 100, the maximum transmit power (power level) of the UE 100, the duplex mode of the UE 100, and the like.

[0223] S413 . The mobile communication module sends the radio resource control layer message 40 to the TN-CN via the TN-RAN. The radio resource control layer message 40 includes the non-terrestrial network user equipment capability message 41 .

[0224] The mobile communication module may generate a non-terrestrial network user equipment capability message 41 based on the NTN air interface capability information provided by the NTN communication module. The mobile communication module may encapsulate the non-terrestrial network user equipment capability message 41 to obtain a radio resource control layer message 40. The mobile communication module may send the radio resource control layer message 40 to the TN-RAN. The TN-RAN may send the radio resource control layer message 40 to the TN-CN.

[0225] S414. TN-CN sends N1 NTN Container 42 to NTN-CN. N1 NTN Container 42 includes the non-terrestrial network user equipment capability indication message 43.

[0226] After receiving radio resource control layer message 40, the TN-CN may parse the message to obtain a non-terrestrial network user equipment capability message 41. Based on non-terrestrial network user equipment capability message 41, the TN-CN may generate a non-terrestrial network user equipment capability indication message 43. The TN-CN may encapsulate non-terrestrial network user equipment capability indication message 43 to obtain an N1 NTN Container 42, and send N1 NTN Container 42 to the NTN-CN. In some examples, a description of the non-terrestrial network user equipment capability message can be found in the description of the user equipment air interface capability information message shown in FIG. A description of the non-terrestrial network user equipment capability indication message can be found in the description of the user equipment air interface capability information indication message shown in FIG.

[0227] After receiving the N1 NTN Container 42, the NTN-CN can parse the non-terrestrial network user equipment capability indication message 43 to obtain the NTN air interface capability information of the NTN communication module of the UE 100. After the UE 100 registers with the NTN-CN, the NTN-CN can allocate communication resources to the UE 100 based on the NTN air interface capability information of the UE 100.

[0228] In other examples, the mobile communication module may place the non-terrestrial network user equipment capabilities message 41 in an N1 NTN container, and then encapsulate the N1 NTN container to obtain a radio resource control layer message 40. The mobile communication module may send the radio resource control layer message 40 to the TN-RAN. The TN-RAN may send the radio resource control layer message 40 to the TN-CN. The TN-CN may obtain the non-terrestrial network user equipment capabilities message 41 based on the radio resource control layer message 40, and then execute step S414 to send the NTN air interface capabilities information of the UE 100 to the NTN-CN. In this way, the TN-RAN can directly forward the N1 NTN container to the TN-CN without parsing the N1 NTN container, saving transmission time.

[0229] In other examples, the mobile communication module may encapsulate the non-terrestrial network user equipment capability message 41 to obtain a radio resource control layer message 40. The mobile communication module may send the radio resource control layer message 40 to the TN-RAN. The TN-RAN may parse the radio resource control layer message 40 to obtain the non-terrestrial network user equipment capability message 41. The TN-RAN may generate a non-terrestrial network user equipment capability indication message 43 based on the non-terrestrial network user equipment capability message 41. The TN-RAN may send the non-terrestrial network user equipment capability indication message 43 to the NTN-CN via the TN-CN, or the TN-RAN may send the non-terrestrial network user equipment capability indication message 43 directly to the NTN-CN. In this way, the message sent from the UE 100 to the NTN-CN can be processed by the TN-RAN, so that the TN-CN does not need to process the NTN-CN message.

[0230] In other examples, the mobile communication module may generate a non-terrestrial network user equipment capability indication message 43 based on the NTN air interface capability information. The mobile communication module may send the non-terrestrial network user equipment capability indication message 43 to the NTN-CN via the TN-RAN and the TN-CN, or the mobile communication module may send the non-terrestrial network user equipment capability indication message 43 to the NTN-CN via the TN-RAN.

[0231] It should be noted that the non-terrestrial network user equipment capability indication message 43 and the non-terrestrial network user equipment capability message 41 are only examples. The mobile communication module can use other signaling carrying the NTN air interface capability information of UE100 to send the NTN air interface capability information of UE100 to NTN-CN through TN-RAN and TN-CN. The embodiment of the present application is not limited to this.

[0232] In this way, through steps S408 to S414, the NTN-CN can obtain the NTN air interface capability information of the NTN communication module of the UE 100 under the TN. When the UE 100 is registered with the NTN-CN, the UE 100 does not need to transmit the NTN air interface capability information of the UE 100 under the NTN, thereby saving air interface resources, time, and power consumption for transmitting the NTN air interface capability information.

[0233] S415. UE 100 searches for NTN, establishes a radio resource control connection with NTN-RAN, and sends a registration request message 44 to NTN-CN via NTN-RAN.

[0234] UE 100 searching for the NTN can be understood as receiving a signal from the NTN. For example, UE 100 can receive a signal from the NTN-RAN (e.g., base station 200) based on the PLMN information stored in the NTN communication module. After receiving the signal from the NTN-RAN, UE 100 can establish an RRC connection with the NTN-RAN. For details, see the embodiment shown in FIG2 , which will not be further described here.

[0235] It should be noted that before searching for NTNs, UE 100 must perform a satellite alignment operation to align the UE 100's antenna radiation direction with the direction of the satellite transmission link of base station 200. UE 100 can display a satellite alignment prompt to prompt the user to align the UE 100's antenna radiation direction with the direction of the satellite transmission link of base station 200. After successful alignment, UE 100 can receive satellite signals with strong signal quality.

[0236] After UE 100 establishes an RRC connection with NTN-RAN, the NTN communication module may send a registration request message 44 to NTN-CN via NTN-RAN. The registration type of registration request message 44 is mobility registration (mobility registration update). For example, registration request message 44 may be expressed as "registration request (mobility registration update)." Registration request message 44 includes the identity of the NTN communication module.

[0237] Based on the identity of the NTN communication module, the NTN-CN can determine whether the NTN-CN stores the NTN air interface capability information of the NTN communication module of UE 100. If the NTN-CN determines that the NTN air interface capability information of the NTN communication module of UE 100 is stored, step S416 can be executed. In this way, each device does not need to perform the steps of synchronizing the NTN air interface capability information of UE 100 as shown in steps S408-S414. The NTN-CN can also synchronize the NTN air interface capability information of UE 100 with the NTN-RAN.

[0238] When the NTN-CN determines that the NTN air interface capability information of the NTN communication module of the UE 100 is not stored, step S417 may be executed to obtain the NTN air interface capability information of the UE 100 through the NTN-RAN.

[0239] S416 . The NTN-CN sends an initial context setup request message 45 and a registration accept message 46 carrying the NTN air interface capability information of the UE 100 to the NTN-RAN.

[0240] After receiving the registration request message 44 sent by UE 100, NTN-CN determines that the registration context and NTN air interface capability information of UE 100's NTN communication module are stored based on the identity of the NTN communication module. NTN-CN may send a registration accept message 46 to UE 100. After receiving the registration accept message 46, NTN-RAN may forward the registration accept message 46 to UE 100. Registration accept message 46 may notify UE 100 of the successful registration with NTN-CN.

[0241] The NTN-CN may also send an Initial Context Setup Request message 45 to the NTN-RAN. Upon receiving the Initial Context Setup Request message 45, the NTN-RAN may parse the message and obtain the NTN air interface capability information of the UE 100. In this way, the NTN-RAN obtains the NTN air interface capability information of the UE 100. Based on the NTN air interface capability information of the UE 100, the NTN-RAN may configure relevant parameters and provide appropriate communication resources for the UE 100. In some examples, the NTN-CN may send the Initial Context Setup Request message 45 via the NGAP air interface. It should be noted that the Initial Context Setup Request message 45 is merely an example. The NTN-CN may also transmit the NTN air interface capability information of the UE 100 to the NTN-RAN via other signaling that carries the NTN air interface capability information of the UE 100. For example, the NTN-CN may transmit the NTN air interface capability information of the UE 100 to the NTN-RAN via signaling that is solely used to transmit the NTN air interface capability information of the UE 100. This is not a limitation in the present embodiment.

[0242] S417 . NTN-CN sends an initial context setup request message 47 and a registration accept message 48 to NTN-RAN, which do not carry the NTN air interface capability information of UE 100 .

[0243] After receiving the registration request message 44 sent by UE 100, NTN-CN determines that the registration context of UE 100's NTN communication module is stored based on the identity of the NTN communication module. NTN-CN may send a registration accept message 48 to NTN-RAN. NTN-RAN may send registration accept message 48 to UE 100. Registration accept message 48 may notify UE 100 of the successful registration with NTN-CN.

[0244] After receiving the registration request message 44 sent by UE 100, NTN-CN determines, based on the identity of the NTN communication module, that it does not store the NTN air interface capability information of UE 100's NTN communication module. NTN-CN may send an initial context setup request message 47 to NTN-RAN. After receiving the initial context setup request message 47, NTN-RAN may parse the message and determine that the initial context setup request message 47 does not include the NTN air interface capability information of UE 100, and then proceed to step S418.

[0245] S418. NTN-RAN obtains the NTN air interface capability information of UE 100 and sends the NTN air interface capability information of UE 100 to NTN-CN.

[0246] The description of NTN-RAN acquiring the NTN air interface capability information of UE 100 and synchronizing the NTN air interface capability information of UE 100 with NTN-CN can be referred to the description of step S222 to step S224 shown in FIG. 2 , which will not be repeated here.

[0247] In this way, the NTN-CN can obtain the NTN air interface capability information of the UE 100 under the TN.

[0248] In some examples, after the NTN-CN obtains the NTN air interface capability information of UE 100, the capabilities of UE 100 change. The NTN communication module of UE 100 may send a notification message to NTN-CN via the mobile communication module, TN-RAN, and TN-CN, indicating the update of the NTN air interface capability information of UE 100. NTN-CN may delete the stored NTN air interface capability information of UE 100. NTN-CN may also obtain the updated NTN air interface capability information from UE 100 via TN-CN, TN-RAN, and the mobile communication module. NTN-CN may also send the NTN air interface capability information of UE 100 to NTN-RAN after receiving a registration request message sent by UE 100 via NTN-RAN. In this way, UE 100 can notify NTN-CN of the capability change. After receiving the capability change message of UE 100, NTN-CN can re-obtain the updated NTN air interface capability information of UE 100, ensuring the reliability of the stored NTN air interface capability information of UE 100.

[0249] For example, as shown in FIG5 , the UE 100 capability change process includes the following steps:

[0250] S501. NTN communication module capability changed.

[0251] After the capability is changed, the NTN communication module may notify the NTN-CN of the capability change of the UE 100 through the mobile communication module, the TN-RAN, and the TN-CN.

[0252] S502. The NTN communication module sends a user equipment capability release command message 51 to the mobile communication module.

[0253] Although the UE 100 has established a communication connection with the TN-CN and is in a connected state, the UE 100 does not need to change the NTN air interface capability information stored in the TN-CN, and therefore the UE 100 does not need to release the connected state.

[0254] The user equipment capability release command message 51 may be used to notify the NTN-CN of the capability change of the UE 100 .

[0255] S503 . The mobile communication module sends a non-access stratum message 52 to the TN-CN via the TN-RAN. The non-access stratum message 52 includes an N1 NTN Container 53 . The N1 NTN Container 53 includes a user equipment capability release command message 51 .

[0256] After receiving the user equipment capability release command message 51 sent by the NTN communication module, the mobile communication module may encapsulate the user equipment capability release command message 51 to obtain an N1 NTN Container 53. The mobile communication module may also encapsulate the N1 NTN Container 53 to obtain a non-access stratum message 52.

[0257] S504. TN-CN sends N1 NTN Container 53 to NTN-CN.

[0258] After receiving the non-access layer message 52, the TN-CN may parse the message to obtain the N1 NTN Container 53, and send the N1 NTN Container 53 to the NTN-CN.

[0259] S505 . NTN-CN sends N1 NTN Container 54 to TN-CN. N1 NTN Container 54 includes non-terrestrial network air interface capability request 55 .

[0260] After receiving N1 NTN Container 53, NTN-CN may parse N1 NTN Container 53 to obtain UE capability release command message 51. NTN-CN may delete UE 100's NTN air interface capability information and send N1 NTN Container 54 including non-terrestrial network air interface capability request 55 to TN-CN. Non-terrestrial network air interface capability request 55 is used to obtain UE 100's NTN air interface capability information.

[0261] In other examples, the NTN communication module may send a registration request message with a registration type of mobility registration to the mobile communication module. This registration request message is used to indicate a change in the NTN air interface capabilities of UE 100. The mobile communication module may send the registration request message to the TN-RAN. The TN-RAN may generate a user equipment capability release command message based on the registration request message. The TN-RAN may send the user equipment capability release command message to the TN-CN, which then sends the message to the NTN-CN. Alternatively, the TN-RAN may send the user equipment capability release command message to the NTN-CN. In this way, the TN-RAN may send a message indicating a change in the NTN air interface capabilities of UE 100 to the NTN-CN.

[0262] In other examples, the NTN communication module may send a registration request message with a registration type of mobility registration to the mobile communication module. The mobile communication module may send the registration request message to the TN-CN via the TN-RAN. The TN-CN may generate a user equipment capability release command message based on the registration request message. The TN-CN may send the message to the NTN-CN.

[0263] S506 . The TN-CN sends a non-access stratum message 56 to the mobile communication module via the TN-RAN. The non-access stratum message 56 includes an N1 NTN Container 54 .

[0264] After receiving the N1 NTN Container 54 , the TN-CN may encapsulate the N1 NTN Container 54 to obtain a non-access layer message 56 , and send the non-access layer message 56 to the mobile communication module through the TN-RAN.

[0265] In other examples, the TN-CN may place the non-terrestrial network air interface capability request 55 in an N1 NTN Container, encapsulate the N1 NTN Container to obtain a radio resource control message, and send the radio resource control message to the TN-RAN. The TN-RAN may forward the radio resource control message to the mobile communication module of the UE 100.

[0266] In other examples, after determining that the NTN air interface capabilities of UE 100 have changed, the NTN-CN may send a non-terrestrial network air interface capability information request message to the TN-CN. The TN-CN may forward this message to the TN-RAN. Upon receiving this message, the TN-RAN may send a user equipment capability query message to the mobile communication module. For details, see the embodiment shown in FIG4 , which will not be further described here.

[0267] In other examples, the NTN-CN may send a non-terrestrial network air interface capability information request message to the TN-CN. Upon receiving the message, the TN-CN may send a user equipment capability query message to the TN-RAN. The TN-RAN may send the user equipment capability query message to the mobile communication module. Upon receiving the message, the mobile communication module may proceed to step S507.

[0268] S507. The mobile communication module obtains the NTN air interface capability information of the NTN communication module operating independently.

[0269] The description of S507 can refer to the description of step S412 shown in FIG4 , and will not be repeated here.

[0270] S508 . The mobile communication module sends the non-access stratum message 57 to the TN-CN via the TN-RAN. The non-access stratum message 57 includes an N1 NTN Container 58 . The N1 NTN Container 58 includes a non-terrestrial network user equipment capability message 59 .

[0271] After obtaining the NTN air interface capability information of the NTN communication module operating independently, the mobile communication module can generate a non-terrestrial network user equipment capability message 59 based on the NTN air interface capability information. The mobile communication module can also encapsulate the non-terrestrial network user equipment capability message 59 into an N1 NTN container 58, and then encapsulate the N1 NTN container 58 into a non-access stratum message 57. The mobile communication module can send the non-access stratum message 57 to the TN-CN via the TN-RAN. The description of step 508 can also be found in the description of step S413 shown in Figure 4 and is not repeated here.

[0272] S509 . TN-CN sends N1 NTN Container 60 to NTN-CN. N1 NTN Container 60 includes non-terrestrial network user equipment capability indication message 61 .

[0273] The non-terrestrial network user equipment capability indication message 61 may include the NTN air interface capability information of the UE 100. The NTN-CN device may obtain the NTN air interface capability information of the UE 100 based on the message.

[0274] S510. UE 100 searches for NTN, establishes a radio resource control connection with NTN-RAN, and sends a registration request message 62 to NTN-CN via NTN-RAN.

[0275] Based on the identity of the NTN communication module, the NTN-CN may determine whether the NTN-CN stores the NTN air interface capability information of the NTN communication module of the UE 100. If the NTN-CN determines that the NTN air interface capability information of the NTN communication module of the UE 100 is stored, step S511 may be executed. If the NTN-CN determines that the NTN air interface capability information of the NTN communication module of the UE 100 is not stored, step S512 may be executed.

[0276] S511 . NTN-CN sends an initial context setup request message 63 and a registration accept message 64 carrying the NTN air interface capability information of UE 100 to NTN-RAN.

[0277] S512 . The NTN-CN sends an initial context setup request message 65 and a registration accept message 66 to the NTN-RAN, which do not carry the NTN air interface capability information of the UE 100 .

[0278] S513. NTN-RAN obtains the NTN air interface capability information of UE 100 and sends the NTN air interface capability information of UE 100 to NTN-CN.

[0279] The description of steps S509 to S513 can refer to the description of steps S414 to S418 shown in FIG4 , and will not be repeated here.

[0280] In this way, when the UE 100 changes the capability of the UE 100 when the NTN communication module operates independently under the TN, the updated NTN air interface capability information of the UE 100 can be synchronized to the NTN-CN through the steps shown in FIG. 5 .

[0281] In one possible implementation, the NTN communication module can perform the registration process for the non-terrestrial core network via the mobile communication module and the terrestrial radio access network. The NTN communication module can also transmit the UE's NTN air interface capability information to the non-terrestrial core network via the mobile communication module and the terrestrial radio access network. This allows the UE 100 to transmit signaling to the NTN-CN via the TN-RAN within the terrestrial network and receive signaling from the NTN-CN via the TN-RAN. Signaling exchange between the UE 100 and the NTN-CN can be accomplished via the TN-RAN, eliminating the need for relaying via the TN-CN and saving signaling time.

[0282] Exemplarily, as shown in FIG6 , the capability synchronization method includes the following steps:

[0283] S601. The mobile communication module of UE100 receives the non-terrestrial network registration request message 71 from the NTN communication module.

[0284] For details, please refer to the description of step S401 shown in FIG4 , which will not be repeated here.

[0285] S602 . The mobile communication module of UE 100 sends a non-access stratum message 72 to NTN-CN via TN-RAN. The non-access stratum message 72 includes an N1 NTN Container 73 . The N1 NTN Container 73 includes a non-terrestrial network registration request message 71 .

[0286] Exemplarily, the non-access stratum message 72 may be expressed as NAS message 72 (N1 NTN Container 73 (NTN registration request 71 (initial registration))). Thus, compared with steps S403 and S404 shown in FIG4 , the UE 100 may send the non-access stratum message 72 to the NTN-CN only through the TN-RAN without the need for TN-CN transit.

[0287] S603. NTN-CN obtains the identity of the NTN communication module.

[0288] NTN-CN can obtain the identity of the NTN communication module through TN-RAN and the mobile communication module. Here, the identity of the NTN communication module is the SIM2 identity.

[0289] For example, the NTN-CN can send a non-access stratum message to the mobile communication module of UE 100 via the TN-RAN. The non-access stratum message includes an N1 NTN container, which includes a non-terrestrial network identity request message. The non-terrestrial network identity request message is used to obtain the identity of the NTN communication module of UE 100. The mobile communication module of UE 100 sends the non-terrestrial network identity request message to the NTN communication module of UE 100.

[0290] After receiving the non-terrestrial network identity request message, the NTN communication module generates a non-terrestrial network identity response message based on the NTN communication module's identity and sends it to the mobile communication module. The mobile communication module then sends a non-access stratum message to the NTN-CN via the TN-RAN. This non-access stratum message includes an N1 NTN container, which contains the non-terrestrial network identity response message. In this way, the NTN-CN obtains the identity of the NTN communication module of UE 100 through the TN-RAN and the mobile communication module. Compared to step S405 shown in Figure 4, this reduces the resources consumed by the NTN-CN for transit.

[0291] S604. NTN-CN authenticates SIM2 bound to the NTN communication module.

[0292] For example, the NTN-CN can send a non-access stratum message to the mobile communication module of UE 100 via the TN-RAN. The non-access stratum message includes an N1 NTN container, which includes a non-terrestrial network authentication request message. The non-terrestrial network authentication request message is used to authenticate SIM2 bound to the NTN communication module of UE 100. The mobile communication module of UE 100 sends the non-terrestrial network authentication request message to the NTN communication module of UE 100.

[0293] After receiving the non-terrestrial network authentication request message, the NTN communication module can calculate an authentication response by combining the authentication parameters of SIM2 and the authentication parameters of the non-terrestrial network authentication request message through an authentication algorithm. Based on the authentication response, the NTN communication module generates a non-terrestrial network authentication response message. The NTN communication module sends this non-terrestrial network authentication response message to the mobile communication module. The mobile communication module sends a non-access stratum message to the NTN-CN via the TN-RAN. This non-access stratum message includes an N1 NTN container, which contains the non-terrestrial network authentication response message. Based on the authentication response in the non-terrestrial network authentication response message, the NTN-CN can determine whether the UE 100 is authenticated. In this case, the NTN-CN authenticates the UE 100 successfully. In this way, the NTN-CN authenticates the SIM2 bound to the NTN communication module of the UE 100 through the TN-RAN and the mobile communication module. Compared to step S406 shown in FIG4 , this reduces the resources consumed by the NTN-CN for transit.

[0294] S605. NTN-CN notifies the NTN communication module to configure the security mode.

[0295] For example, the NTN-CN can send a non-access stratum message to the mobile communication module of UE 100 via the TN-RAN. The non-access stratum message includes an N1 NTN container, which includes a non-terrestrial network security mode command message. The non-terrestrial network security mode command message is used to notify the NTN communication module of UE 100 to configure a security mode. The mobile communication module of UE 100 sends the non-terrestrial network security mode command message to the NTN communication module of UE 100.

[0296] After receiving the non-terrestrial network security mode command message, the NTN communication module can determine the encryption algorithm and integrity algorithm. UE 100 can then process the uplink data sent to NTN-CN using the obtained encryption algorithm and integrity algorithm. The NTN communication module can also generate a non-terrestrial network security mode complete message after receiving the non-terrestrial network security mode command message and send the non-terrestrial network security mode complete message to the mobile communication module. The mobile communication module sends a non-access stratum message to NTN-CN via TN-RAN. The non-access stratum message includes an N1 NTN Container, which includes the non-terrestrial network security mode complete message. Based on the non-terrestrial network security mode complete message, NTN-CN can determine that UE 100 has completed security mode configuration. In this way, NTN-CN notifies UE 100's NTN communication module of security mode configuration via TN-RAN and the mobile communication module. Compared to step S406 shown in Figure 4, this reduces the resources consumed by NTN-CN for transit.

[0297] S606 . The NTN-CN sends a non-access stratum message 74 to the TN-RAN. The non-access stratum message 74 includes an N1 NTN Container 75 . The N1 NTN Container 75 includes a non-terrestrial network registration accept message 76 .

[0298] S607 . TN-RAN sends a non-access stratum message 74 to the mobile communication module of UE 100 .

[0299] After the UE 100 passes identity authentication, authorization, and security mode configuration, the NTN-CN may send a non-terrestrial network registration acceptance message 76 to the mobile communication module via the TN-RAN. The non-terrestrial network registration acceptance message 76 may indicate that the NTN-CN accepts the registration request of the UE 100.

[0300] S608. The mobile communication module sends a non-terrestrial network registration acceptance message 76 to the NTN communication module.

[0301] S609 . The NTN-CN sends a radio resource control layer message 77 , including a non-terrestrial network air interface capability request 78 , to the mobile communication module of the UE 100 via the TN-RAN.

[0302] The NTN-CN can also send a radio resource control layer message 77 including a non-terrestrial network air interface capability request 78 to the mobile communication module via the TN-RAN. The non-terrestrial network air interface capability request 78 can be used to obtain NTN air interface capability information of the NTN communication module of the UE 100 when operating independently. For example, the NTN-CN can place the non-terrestrial network air interface capability request 78 in an N1 NTN container, and then encapsulate the N1 NTN container to obtain the radio resource control message 77.

[0303] In other examples, the NTN-CN may send a NAS message including the non-terrestrial network air interface capability request 78 to the TN-RAN. For example, the NTN-CN may place the non-terrestrial network air interface capability request 78 in an N1 NTN container and then encapsulate the N1 NTN container to obtain a NAS message. The TN-RAN may encapsulate the NAS message to obtain an RRC message and then send the RRC message to the mobile communication module of the UE 100.

[0304] In other examples, the NTN-CN may send a non-terrestrial network air interface capability information request message to the TN-RAN. After receiving the message, the TN-RAN may send a user equipment capability query message to the NTN communication module via the mobile communication module. The user equipment capability query message includes parameters for instructing the UE 100 to send the NTN air interface capability information to the TN-RAN.

[0305] For example, the NTN-CN may forward the non-terrestrial network air interface capability information request message to the TN-RAN via NGAP. The TN-RAN may generate a user equipment capability query message based on the non-terrestrial network air interface capability information request message. The NTN-RAN may include the user equipment capability query message in an RRC message and send the RRC message to UE 100. For example, the RRC message includes an N1 NTN container, which includes the user equipment capability query message. For example, the user equipment capability query message may be UE capability enquiry (NTN).

[0306] In some examples, the NTN-CN may place the non-terrestrial network registration accept message 76 and the non-terrestrial network air interface capability request 78 in the same NAS message and send the NAS message to the TN-RAN. The TN-RAN may obtain an RRC message 84 based on the non-terrestrial network registration accept message 76 and send the RRC message 84 to the UE 100. The TN-RAN may also obtain an RRC message 85 based on the non-terrestrial network air interface capability request 78 and send the RRC message 85 to the UE 100.

[0307] S610. The mobile communication module obtains the air interface capability information of the NTN communication module operating independently.

[0308] For details, please refer to the embodiment shown in FIG4 , which will not be described in detail here.

[0309] S611 . The mobile communication module sends the radio resource control layer message 79 to the NTN-CN via the TN-RAN. The radio resource control layer message 79 includes the non-terrestrial network user equipment capability message 80 .

[0310] For example, the mobile communication module may generate a non-terrestrial network user equipment capability message 80 based on the NTN air interface capability information provided by the NTN communication module. The mobile communication module may encapsulate the non-terrestrial network user equipment capability message 80 to obtain a radio resource control layer message 79. The mobile communication module may send the radio resource control layer message 79 to the TN-RAN. The TN-RAN may send the radio resource control layer message 79 to the NTN-CN. Optionally, the mobile communication module may encapsulate the non-terrestrial network user equipment capability message 80 to obtain a NAS message, and then encapsulate the NAS message to obtain the radio resource control layer message 79. The TN-RAN may send the NAS message to the NTN-CN.

[0311] In some examples, the mobile communication module may send a non-terrestrial network user equipment capability message 80 to the TN-RAN. The TN-RAN may generate a non-terrestrial network user equipment capability indication message based on the non-terrestrial network user equipment capability message 80. The TN-RAN may send the non-terrestrial network user equipment capability indication message to the NTN-CN. For a description of the mobile communication module sending a message to the TN-RAN, please refer to the embodiment shown in FIG. 4 , and will not be repeated here. For a description of the TN-RAN sending a message to the NTN-CN, please refer to the description of the TN-RAN sending a message to the TN-CN in FIG. 4 , or refer to the description of the TN-CN sending a message to the NTN-CN in FIG. 4 , and will not be repeated here.

[0312] It should be noted that the non-terrestrial network user equipment capability indication message and the non-terrestrial network user equipment capability message 80 are only examples. The mobile communication module can use other signaling carrying the NTN air interface capability information of UE100 to send the NTN air interface capability information of UE100 to NTN-CN through TN-RAN. The embodiment of the present application is not limited to this.

[0313] S612. UE 100 searches for NTN, establishes a radio resource control connection with NTN-RAN, and sends a registration request message 81 to NTN-CN via NTN-RAN.

[0314] S613 . The NTN-CN sends an initial context setup request message 82 and a registration accept message 83 carrying the NTN air interface capability information of the UE 100 to the NTN-RAN.

[0315] The description of step S612 and step S613 can be found in the embodiment shown in FIG4 , and will not be repeated here. In this way, the UE 100 and the NTN-CN do not need to be relayed through the TN-CN, and the signaling interaction process can be implemented through the TN-RAN, saving the time required for signaling transmission.

[0316] In one possible implementation, UE 100 includes SIM 3. UE 100 can use TN communication services and NTN roaming services through SIM 3. When registering with the TN network, UE 100 can send SIM 3's NTN capability information to the TN-CN, and TN-CN can send a list of equivalent public land mobile networks (EPLMNs) of NTN PLMNs to UE 100. After receiving the list, UE 100 can send an air interface capability change message to TN-CN. The air interface capability change message can be used to trigger TN-CN to obtain UE 100's NTN air interface capability information. UE 100 can search for NTN based on the EPLMN list and send a registration request message to NTN-CN. After receiving the registration request message from UE 100, NTN-CN can obtain UE 100's registration context and UE 100's NTN air interface capability information from TN-CN. NTN-CN can send UE 100's NTN air interface capability information to NTN-RAN. In this way, UE 100 can send its NTN air interface capability information to TN-CN under TN. When NTN-CN receives the registration request message from UE 100, it can obtain the registration context of UE 100 and the NTN air interface capability information of UE 100 from TN-CN, thus saving NTN air interface resources.

[0317] In some examples, the air interface capability change message includes parameters for indicating a change in the NTN air interface capability of the UE 100. For example, the air interface capability change message may be a registration request message with a registration type of mobility registration, a user equipment capability release command message, and the like.

[0318] As shown in FIG7 , the capability synchronization method provided in the embodiment of the present application includes the following steps:

[0319] S701. UE 100 sends a registration request message 91 to TN-CN via TN-RAN. Registration request message 91 includes network capability information of SIM3 of UE 100, indicating that UE 100 supports NTN communication.

[0320] When UE 100 sends a registration request message 91 to TN-CN, it may include the network capability information of UE 100. The network capability information may be used to indicate that UE 100 supports access to NTN-CN. UE 100 may send the registration request message 91 to TN-CN via a mobile communication module. Registration request message 91 is used for UE 100 to register with TN-CN.

[0321] S702. TN-CN determines an equivalent public land mobile network EPLMN list of the non-terrestrial network public land mobile network NTN PLMN of UE 100.

[0322] TN-CN has a roaming agreement with NTN-CN, and TN-CN stores NTN-CN's EPLMN list. After receiving registration request message 91 from UE 100, TN-CN determines that UE 100 is capable of communicating with NTN. It then determines the EPLMN list of the NTN PLMNs for SIM3 of UE 100 and sends it to UE 100. This EPLMN list indicates the EPLMNs of NTN for SIM3.

[0323] S703. TN-CN sends a registration accept message 92 to UE 100 via TN-RAN. Registration accept message 92 includes an EPLMN list.

[0324] The TN-CN may add the EPLMN list to a registration acceptance message 92 and send the registration acceptance message 92 to the UE 100 via the TN-RAN. It should be noted that between steps S701 and S703, the UE 100 and the TN-CN also perform steps such as obtaining an identity and performing authentication to register with the network. For a detailed description of the UE 100 registering with the TN-CN, please refer to the embodiment shown in FIG. 2 and will not be repeated here.

[0325] S704. UE 100 sends a registration request message 93 of the registration type of mobility registration to TN-CN via TN-RAN. Registration request message 93 includes parameters for indicating that the NTN air interface capability of UE 100 has changed.

[0326] For example, the description of the registration request message 93 can refer to the description of step S304 shown in FIG3 , which will not be repeated here.

[0327] S705. The TN-CN sends a non-terrestrial network air interface capability request 94 to the UE 100 via the TN-RAN.

[0328] The non-terrestrial network air interface capability request 94 may be used by the TN-CN to obtain the NTN air interface capability information of the UE 100 .

[0329] In some examples, the TN-CN may add the non-terrestrial network air interface capability request 94 to an N1 NTN container, encapsulate the N1 NTN container to obtain a non-access stratum message, and finally send the non-access stratum message via the TN-RAN to the UE 100. Alternatively, the TN-CN may encapsulate the N1 NTN container to obtain a radio resource control layer message, and finally send the radio resource control layer message to the UE 100 via the TN-RAN.

[0330] In other examples, the TN-CN may send a non-terrestrial network air interface capability information request to the TN-RAN. After receiving the message, the TN-RAN may send a user equipment capability query message to the NTN communication module via the mobile communication module.

[0331] For example, the TN-CN may send a non-terrestrial network air interface capability information request to the TN-RAN via NGAP. The TN-RAN may include a user equipment capability query message in an RRC message and send the RRC message to the UE 100. For example, the RRC message includes an N1 NTN container, which includes the user equipment capability query message. The user equipment capability query message includes parameters for instructing the UE 100 to send NTN air interface capability information to the TN-RAN. For example, the user equipment capability query message may be UE capability enquiry (NTN).

[0332] It should be noted that the above signaling is only an example. TN-CN, TN-RAN and UE100 can synchronize the NTN air interface capability information of UE100 through other signaling with the same function. For example, TN-CN can send a non-terrestrial network air interface capability information request to UE100 through TN-RAN to obtain the NTN air interface capability information of UE100.

[0333] S706. UE 100 sends a non-terrestrial network user equipment capability message 95 to TN-CN via TN-RAN.

[0334] After receiving the non-terrestrial network air interface capability request 94, the UE 100 may generate a non-terrestrial network user equipment capability message 95 based on the NTN air interface capability information. The UE 100 may send the non-terrestrial network user equipment capability message 95 to the TN-CN via the TN-RAN.

[0335] After receiving the non-terrestrial network user equipment capability message 95 , the TN-CN may save the identifier of the UE 100 and the NTN air interface capability information of the UE 100 .

[0336] In some examples, UE 100 may add the non-terrestrial network air interface capability message 95 to an N1 NTN container, encapsulate the N1 NTN container to obtain a non-access stratum message, and finally send the non-access stratum message to the TN-CN via the TN-RAN. Alternatively, UE 100 may encapsulate the N1 NTN container to obtain a radio resource control layer message, and finally send the radio resource control layer message to the TN-CN via the TN-RAN.

[0337] In other examples, UE 100 may send a non-terrestrial network user equipment capability message 95 to TN-RAN. After receiving the non-terrestrial network user equipment capability message 95, TN-RAN may send a non-terrestrial network user equipment capability indication message to TN-CN. The non-terrestrial network user equipment capability indication message is used by TN-RAN to synchronize the NTN air interface capability information of UE 100 with TN-CN.

[0338] For example, UE100 can add the non-terrestrial network user equipment capability message 95 to the N1 NTN Container, then encapsulate the N1 NTN Container to obtain an RRC message, and finally send the RRC message to the TN-RAN. The TN-RAN can generate a non-terrestrial network user equipment capability indication message based on the non-terrestrial network user equipment capability message 95, then add the non-terrestrial network user equipment capability indication message to the N1NTN Container, and send the N1 NTN Container to the TN-CN.

[0339] It should be noted that the non-terrestrial network user equipment capability message is only an example, and the UE 100 may also send the NTN air interface capability information of the UE 100 to the TN-CN through other signaling. For example, the UE 100 may send a non-terrestrial network user equipment capability indication message to the TN-CN through the TN-RAN to synchronize the NTN air interface capability information of the UE 100. For another example, the UE 100 may send a non-terrestrial network user equipment capability message to the TN-CN through the TN-RAN to synchronize the NTN air interface capability information of the UE 100, but this embodiment of the present application is not limited to this.

[0340] S707. UE 100 searches for NTN-RAN based on EPLMN.

[0341] UE 100 can search for NTN-RAN based on the EPLMN. UE 100 can also establish an RRC connection with NTN-RAN. For details, see the embodiment shown in FIG2 , which will not be described in detail here. It should be noted that, in order for UE 100 to receive high-quality NTN signals, UE 100 can perform a satellite alignment operation before executing step S707.

[0342] S708. UE 100 sends a registration request message 96 to NTN-CN via NTN-RAN. The registration type of the registration request message 96 is mobility registration.

[0343] UE 100 may send a registration request message 96 with a registration type of mobility registration to NTN-CN via NTN-RAN. Registration request message 96 includes the identifier of UE 100, prompting NTN-CN to obtain the registration context of UE 100 and NTN air interface capability information of UE 100 from TN-CN. The identifier of UE 100 may be a SIM3 identifier, such as the SIM3's SUCI. For example, registration request message 96 may be a registration request (mobility registration update). Both the mobile communication module and the NTN communication module of UE 100 are bound to SIM3. UE 100 may send registration request message 96 to NTN-RAN via the NTN communication module, and NTN-RAN may send registration request message 96 to NTN-CN.

[0344] S709. NTN-CN obtains the registration context of UE 100 and NTN air interface capability information from TN-CN.

[0345] After receiving the registration request message 96, the NTN-CN can obtain the registration context of UE 100 and NTN air interface capability information from the TN-CN. The registration context of UE 100 can be used to indicate whether UE 100 has been authenticated, data encryption, etc. The NTN air interface capability information can be used to indicate the air interface transmission capability of UE 100. For example, the registration context of UE 100 may include, but is not limited to, the paging capability information of UE 100, the aggregate maximum bit rate (AMBR) of UE 100, the authentication information of UE 100, the security mode configuration of UE 100, etc. The NTN-CN can ensure the integrity and security of data transmitted with UE 100 based on the security mode configuration information of UE 100. In this way, UE 100 does not need to perform authentication, security mode configuration, and other steps during the NTN-CN registration process, thereby reducing registration time. For example, the NTN air interface capability information of UE 100 may include, but is not limited to, carriers supported by UE 100, user equipment class of UE 100, antenna polarization direction of UE 100, maximum transmit power (power class) of UE 100, duplex mode of UE 100, etc. In this way, NTN-CN does not need to obtain the NTN air interface capability information of UE 100 through NTN-RAN, thus saving NTN air interface resources and reducing the time for synchronizing the NTN air interface capability information of UE 100 between UE 100 and NTN-CN.

[0346] In other examples, the TN-CN may place the NTN air interface capability information in a registration context and then send the registration context of the UE 100 to the NTN-CN. In this way, the registration context of the UE 100 may include the NTN air interface capability information of the UE 100, and the TN-CN may send the data required by the NTN-CN to the NTN-CN through only one signaling.

[0347] S710. NTN-CN sends an initial context setup request message 97 and a registration accept message 98 carrying NTN air interface capability information to UE 100 via NTN-RAN.

[0348] After obtaining the registration context and NTN air interface capability information of UE 100, NTN-CN can send an Initial Context Setup Request message 97 carrying the NTN air interface capability information of UE 100 and a Registration Accept message 98 to UE 100 via NTN-RAN. Registration Accept message 98 indicates that UE 100 has successfully registered with NTN-CN. NTN-RAN can send Registration Accept message 98 to UE 100.

[0349] After receiving the initial context setup request message 97, the NTN-RAN can parse the message to obtain the NTN air interface capability information of the UE 100. It should be noted that the initial context setup request message 97 is only an example. The NTN-CN can also send the NTN air interface capability information of the UE 100 to the NTN-RAN through other signaling. For example, the UE 100 can send signaling used only to transmit the NTN air interface capability information of the UE 100 to send the NTN air interface capability information of the UE 100 to the NTN-RAN.

[0350] It should be noted that if the NTN-CN does not obtain the NTN air interface capability information of the UE 100 from the TN-CN, the NTN-CN may send an NGAP Initial Context Setup Request message to the NTN-RAN that does not carry the NTN air interface capability information of the UE 100. Upon receiving the message and determining that the message does not include the NTN air interface capability information of the UE 100, the NTN-RAN may obtain the NTN air interface capability information of the UE 100 and send the NTN air interface capability information to the NTN-CN. For details, see the description of steps S417 and S419 shown in FIG. 4 , which will not be repeated here.

[0351] In this way, UE 100 can access NTN-CN in roaming mode without executing the NTN air interface capability synchronization process under NTN, thus saving air interface resources, device power consumption and time spent on transmitting NTN air interface capability information.

[0352] Optionally, the TN-CN may send a non-terrestrial network air interface capability request to the UE 100 through the NTN-RAN when sending a registration accept message including the EMPLN list of the NTN PLMN to the UE 100 through the NTN-RAN. In this way, the UE 100 does not need to send a registration request message with a registration type of mobility registration to trigger the TN-CN to send the non-terrestrial network air interface capability request, thereby saving signaling overhead.

[0353] In one possible implementation, UE 100 accesses a registration server on the Internet via WLAN. Through the registration server, UE 100 can communicate with NTN-CN via signaling for registering UE 100 with NTN-CN, as well as UE 100's NTN air interface capability information, thereby registering UE 100 with NTN-CN. After UE 100 accesses NTN-CN, NTN-CN may not need to obtain UE 100's NTN air interface capability information and synchronize UE 100's NTN air interface capability information with NTN-RAN. For details, please refer to the embodiments shown in Figures 3 or 5 , which will not be described in detail here. Thus, since NTN-CN obtains UE 100's NTN air interface capability information via WLAN, NTN-CN does not need to obtain UE 100's NTN air interface capability information from NTN-RAN.

[0354] In one possible implementation, UE100 includes SIM6. UE100 can use the communication services of TN1 through SIM6 and can use the roaming services of TN2. When registering with the TN1 network, UE100 can send the air interface capability information of SIM6 under TN2 to the CN of TN1, and the CN of TN1 can send the EPLMN list of TN2 to UE100. UE100 can search for TN2 based on the EPLMN list and send a registration request message to the CN of TN2. After receiving the registration request message from UE100, the CN of TN2 can obtain the registration context of UE100 and the air interface capability information under TN2 from the CN of TN1. In this way, UE100 can roam to access TN2 without executing the air interface capability information process of TN2 under TN2, saving the time for the CN of TN2 to obtain the air interface capability information of UE100.

[0355] The electronic device provided by the embodiments of the present application is introduced below.

[0356] UE 100 may be a mobile phone, a tablet computer, a desktop computer, a laptop computer, a handheld computer, a notebook computer, an ultra-mobile personal computer (UMPC), a netbook, a cellular phone, a personal digital assistant (PDA), an augmented reality (AR) device, a virtual reality (VR) device, an artificial intelligence (AI) device, a wearable device, an in-vehicle device, a smart home device, and / or a smart city device. The embodiments of the present application do not impose any particular restrictions on the specific type of the electronic device.

[0357] FIG8 shows a schematic structural diagram of UE 100 .

[0358] UE 100 may include a processor 110, an external memory interface 120, an internal memory 121, a universal serial bus (USB) interface 130, a charging management module 140, a power management module 141, a battery 142, an antenna 1, an antenna 2, a mobile communication module 150, a wireless communication module 160, an audio module 170, a speaker 170A, a receiver 170B, a microphone 170C, an earphone interface 170D, a sensor module 180, a button 190, a motor 191, an indicator 192, a camera 193, a display 194, and a subscriber identification module (SIM) card interface 195, etc. The sensor module 180 may include a pressure sensor 180A, a gyroscope sensor 180B, an air pressure sensor 180C, a magnetic sensor 180D, an acceleration sensor 180E, a distance sensor 180F, a proximity light sensor 180G, a fingerprint sensor 180H, a temperature sensor 180J, a touch sensor 180K, an ambient light sensor 180L, a bone conduction sensor 180M, etc.

[0359] It should be understood that the structure illustrated in the embodiments of the present invention does not constitute a specific limitation on UE 100. In other embodiments of the present application, UE 100 may include more or fewer components than illustrated, or may combine or separate certain components, or may have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0360] The processor 110 may include one or more processing units. For example, the processor 110 may include an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural-network processing unit (NPU). The different processing units may be independent devices or integrated into one or more processors.

[0361] The controller can be the nerve center and command center of the UE 100. The controller can generate operation control signals based on instruction operation codes and timing signals to complete the control of instruction fetching and execution.

[0362] Processor 110 may also include a memory for storing instructions and data. In some embodiments, the memory in processor 110 is a cache memory. This memory can store instructions or data that have just been used or are being recycled by processor 110. If processor 110 needs to use the same instruction or data again, it can directly access the memory. This avoids duplicate accesses, reduces processor 110 latency, and thus improves system efficiency.

[0363] In some embodiments, the processor 110 may include one or more interfaces. The interfaces may include an inter-integrated circuit (I2C) interface, an inter-integrated circuit sound (I2S) interface, a pulse code modulation (PCM) interface, a universal asynchronous receiver / transmitter (UART) interface, a mobile industry processor interface (MIPI), a general-purpose input / output (GPIO) interface, a subscriber identity module (SIM) interface, and / or a universal serial bus (USB) interface.

[0364] It is understood that the interface connection relationship between the modules illustrated in the embodiment of the present invention is only for illustrative purposes and does not constitute a structural limitation on UE 100. In other embodiments of the present application, UE 100 may also adopt different interface connection methods from the above embodiments, or a combination of multiple interface connection methods.

[0365] The charging management module 140 is configured to receive charging input from a charger. The charger can be either a wireless charger or a wired charger. In some wired charging embodiments, the charging management module 140 can receive charging input from the wired charger via the USB interface 130. In some wireless charging embodiments, the charging management module 140 can receive wireless charging input via the wireless charging coil of the UE 100. While charging the battery 142, the charging management module 140 can also power the electronic device via the power management module 141.

[0366] The power management module 141 is used to connect the battery 142, the charging management module 140, and the processor 110. The power management module 141 receives input from the battery 142 and / or the charging management module 140, and provides power to the processor 110, the internal memory 121, the display 194, the camera 193, and the wireless communication module 160. The power management module 141 can also be used to monitor parameters such as battery capacity, battery cycle count, and battery health status (leakage, impedance). In some other embodiments, the power management module 141 can also be set in the processor 110. In other embodiments, the power management module 141 and the charging management module 140 can also be set in the same device.

[0367] The wireless communication function of UE 100 can be implemented through antenna 1, antenna 2, mobile communication module 150, wireless communication module 160, modem processor and baseband processor.

[0368] Antenna 1 and Antenna 2 are used to transmit and receive electromagnetic wave signals. Each antenna in UE 100 can be used to cover a single or multiple communication frequency bands. Different antennas can also be reused to improve antenna utilization. For example, antenna 1 can be reused as a diversity antenna for a wireless local area network. In other embodiments, the antennas can be used in conjunction with a tuning switch.

[0369] The mobile communication module 150 can provide solutions for wireless communications including 2G / 3G / 4G / 5G applied on UE100. The mobile communication module 150 may include at least one filter, a switch, a power amplifier, a low noise amplifier (LNA), etc. The mobile communication module 150 can receive electromagnetic waves from the antenna 1, and filter, amplify, and process the received electromagnetic waves, and transmit them to the modulation and demodulation processor for demodulation. The mobile communication module 150 can also amplify the signal modulated by the modulation and demodulation processor, and convert it into electromagnetic waves for radiation through the antenna 1. In some embodiments, at least some of the functional modules of the mobile communication module 150 can be set in the processor 110. In some embodiments, at least some of the functional modules of the mobile communication module 150 can be set in the same device as at least some of the modules of the processor 110.

[0370] The modem processor may include a modulator and a demodulator. The modulator is used to modulate the low-frequency baseband signal to be transmitted into a medium-high frequency signal. The demodulator is used to demodulate the received electromagnetic wave signal into a low-frequency baseband signal. The demodulator then transmits the demodulated low-frequency baseband signal to the baseband processor for processing. After being processed by the baseband processor, the low-frequency baseband signal is passed to the application processor. The application processor outputs a sound signal through an audio device (not limited to the speaker 170A, the receiver 170B, etc.) or displays an image or video through the display screen 194. In some embodiments, the modem processor may be an independent device. In other embodiments, the modem processor may be independent of the processor 110 and be set in the same device as the mobile communication module 150 or other functional modules.

[0371] The wireless communication module 160 can provide wireless communication solutions applied on UE100, including wireless local area networks (WLAN) (such as wireless fidelity (Wi-Fi) networks), Bluetooth (BT), global navigation satellite system (GNSS), frequency modulation (FM), near field communication (NFC), infrared technology (IR), non-terrestrial network communication modules, etc. The wireless communication module 160 can be one or more devices integrating at least one communication processing module. The wireless communication module 160 receives electromagnetic waves via antenna 2, frequency modulates and filters the electromagnetic wave signals, and sends the processed signals to the processor 110. The wireless communication module 160 can also receive the signal to be sent from the processor 110, frequency modulate it, amplify it, and convert it into electromagnetic waves for radiation through antenna 2.

[0372] The non-terrestrial network communication module (NTN communication module) can be used to process signals sent by UE 100 to the NTN. The non-terrestrial network communication module can also be used to process signals from the NTN. In this embodiment of the present application, the non-terrestrial network communication module can send messages to the NTN-RAN. The non-terrestrial network communication module can also receive messages from the NTN-RAN.

[0373] In some embodiments, antenna 1 of UE 100 is coupled to mobile communication module 150, and antenna 2 is coupled to wireless communication module 160, so that UE 100 can communicate with a network and other devices via wireless communication technologies. The wireless communication technologies may include global system for mobile communications (GSM), general packet radio service (GPRS), code division multiple access (CDMA), wideband code division multiple access (WCDMA), time-division code division multiple access (TD-SCDMA), long term evolution (LTE), BT, GNSS, WLAN, NFC, FM, and / or IR technology. The GNSS may include a global positioning system (GPS), a global navigation satellite system (GLONASS), a Beidou navigation satellite system (BDS), a quasi-zenith satellite system (QZSS) and / or a satellite based augmentation system (SBAS).

[0374] UE 100 implements display functions through a GPU, display screen 194, and an application processor. The GPU is a microprocessor for image processing that connects display screen 194 and the application processor. The GPU is used to perform mathematical and geometric calculations for graphics rendering. Processor 110 may include one or more GPUs that execute program instructions to generate or modify display information.

[0375] Display screen 194 is used to display images, videos, and the like. Display screen 194 includes a display panel. The display panel can be a liquid crystal display (LCD), an organic light-emitting diode (OLED), an active-matrix organic light-emitting diode (AMOLED), a flexible light-emitting diode (FLED), a MiniLED, a MicroLED, a Micro-oLed, or a quantum dot light-emitting diode (QLED). In some embodiments, UE 100 may include one or N display screens 194 , where N is a positive integer greater than one.

[0376] UE 100 can implement a shooting function through an ISP, a camera 193 , a video codec, a GPU, a display 194 , and an application processor.

[0377] The ISP processes data fed back by camera 193. For example, when taking a photo, the shutter is opened, and light is transmitted through the lens to the camera's photosensitive element. The light signal is converted into an electrical signal, which is then passed to the ISP for processing and transformed into a visible image. The ISP can also perform algorithmic optimization on image noise and brightness. It can also optimize parameters such as exposure and color temperature of the captured scene. In some embodiments, the ISP can be located within camera 193.

[0378] The camera 193 is used to capture still images or videos. The object generates an optical image through the lens and projects it onto the photosensitive element. The photosensitive element can be a charge coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) phototransistor. The photosensitive element converts the optical signal into an electrical signal, and then passes the electrical signal to the ISP to be converted into a digital image signal. The ISP outputs the digital image signal to the DSP for processing. The DSP converts the digital image signal into an image signal in a standard RGB, YUV or other format. In some embodiments, the UE 100 may include 1 or N cameras 193, where N is a positive integer greater than 1.

[0379] The digital signal processor is used to process digital signals. In addition to processing digital image signals, it can also process other digital signals. For example, when the UE 100 selects a frequency point, the digital signal processor is used to perform Fourier transform on the frequency point energy.

[0380] Video codecs are used to compress or decompress digital video. UE 100 may support one or more video codecs. This allows UE 100 to play or record videos in various encoding formats, such as Moving Picture Experts Group (MPEG) 1, MPEG2, MPEG3, and MPEG4.

[0381] The NPU is a neural network (NN) computing processor. Drawing on the structure of biological neural networks, such as the transmission patterns between neurons in the human brain, it rapidly processes input information and can continuously self-learn. The NPU enables intelligent cognitive applications such as image recognition, face recognition, speech recognition, and text comprehension in the UE100.

[0382] The external memory interface 120 can be used to connect to an external non-volatile memory to expand the storage capacity of the UE 100. The external non-volatile memory communicates with the processor 110 via the external memory interface 120 to implement data storage. For example, files such as music and videos can be stored in the external non-volatile memory.

[0383] The internal memory 121 can be used to store computer executable program code, which includes instructions. The processor 110 executes various functional applications and data processing of UE100 by running the instructions stored in the internal memory 121. The internal memory 121 may include a program storage area and a data storage area. Among them, the program storage area can store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc. The data storage area can store data created during the use of UE100 (such as audio data, a phone book, etc.), etc. In addition, the internal memory 121 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, a universal flash storage (UFS), etc.

[0384] The UE 100 can implement audio functions such as music playback and recording through the audio module 170 , the speaker 170A, the receiver 170B, the microphone 170C, the headphone jack 170D, and the application processor.

[0385] Audio module 170 is used to convert digital audio information into analog audio signals for output, and also to convert analog audio input into digital audio signals. Speaker 170A, also known as a "horn," is used to convert audio electrical signals into sound signals. Receiver 170B, also known as a "handset," is used to convert audio electrical signals into sound signals. Microphone 170C, also known as a "microphone," is used to convert sound signals into electrical signals.

[0386] The pressure sensor 180A senses pressure signals and converts them into electrical signals. In some embodiments, the pressure sensor 180A can be located on the display screen 194. The gyroscope sensor 180B can be used to determine the motion posture of the UE 100. The air pressure sensor 180C measures air pressure. The magnetic sensor 180D includes a Hall effect sensor and can be used to detect the opening and closing of the flip case. The acceleration sensor 180E detects the magnitude of acceleration of the UE 100 in various directions (generally three axes). The distance sensor 180F measures distance. The proximity light sensor 180G can also be used for automatic unlocking and locking in the case mode and pocket mode. The ambient light sensor 180L senses ambient light brightness. The fingerprint sensor 180H collects fingerprints. The temperature sensor 180J detects temperature. The touch sensor 180K, also known as the "touch panel," can be located on the display screen 194. The touch sensor 180K and the display screen 194 form a touch screen, also known as a "touch screen." The touch sensor 180K is used to detect touch operations applied thereto or in the vicinity thereof. The touch sensor can transmit the detected touch operations to the application processor to determine the type of touch event. Visual output related to the touch operations can be provided via the display screen 194. In other embodiments, the touch sensor 180K can also be provided on the surface of the UE 100, at a location different from that of the display screen 194. The bone conduction sensor 180M can obtain vibration signals. The buttons 190 include a power button, a volume button, etc. The motor 191 can generate vibration prompts. The indicator 192 can be an indicator light that can be used to indicate the charging status, power level changes, messages, missed calls, notifications, etc.

[0387] The SIM card interface 195 is used to connect SIM cards, for example, SIM1, SIM2, and SIM3. The SIM card can be connected to and separated from the UE 100 by inserting it into the SIM card interface 195 or removing it from the SIM card interface 195. The UE 100 can support 1 or N SIM card interfaces, where N is a positive integer greater than 1. The SIM card interface 195 can support Nano SIM cards, Micro SIM cards, SIM cards, and the like. Multiple cards can be inserted into the same SIM card interface 195 at the same time. The types of the multiple cards can be the same or different. The SIM card interface 195 can also be compatible with different types of SIM cards. The SIM card interface 195 can also be compatible with external memory cards. The UE 100 interacts with the network through the SIM card to implement functions such as calls and data communications. In some embodiments, the UE 100 uses an eSIM, i.e., an embedded SIM card. The eSIM card can be embedded in the UE 100 and cannot be separated from the UE 100.

[0388] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A capability synchronization method, characterized in that: Applied to a communication system, the communication system includes a user equipment UE, a core network NTN-CN device of a non-terrestrial network, a radio access network device NTN-RAN of a non-terrestrial network, and a terrestrial network device; the method includes: The UE receives a first non-terrestrial network air interface capability request sent by the terrestrial network device, and sends a first non-terrestrial network air interface capability message to the terrestrial network device, where the first non-terrestrial network air interface capability message includes the NTN air interface capability information of the UE; The terrestrial network device sends a second non-terrestrial network air interface capability message to the NTN-CN device, where the second non-terrestrial network air interface capability message includes the NTN air interface capability information of the UE; The UE searches for the NTN, and sends a first mobility registration request message to the NTN-CN device through the NTN-RAN device, where the first mobility registration request message is used for the UE to register with the NTN-CN device; After receiving the first mobility registration request message, the NTN-CN device sends the NTN air interface capability information of the UE to the NTN-RAN device.

2. The method according to claim 1, characterized in that Before the UE receives the first non-terrestrial network air interface capability request, the method further includes: After the UE registers with the NTN-CN device through the ground network device, the NTN-CN device sends a second non-ground network air interface capability request to the ground network device, where the second non-ground network air interface capability request is used by the NTN-CN device to obtain NTN air interface capability information of the UE; After receiving the second non-terrestrial network air interface capability request, the terrestrial network device sends the first non-terrestrial network air interface capability request to the UE.

3. The method according to claim 2, characterized in that The terrestrial network device includes a TN-RAN device of a terrestrial network and a TN-CN device of a core network of the terrestrial network; after receiving the second non-terrestrial network air interface capability request, the terrestrial network device sends the first non-terrestrial network air interface capability request to the UE, specifically including: The TN-CN device receives the second non-terrestrial network air interface capability request, and sends the first non-terrestrial network air interface capability request to the TN-RAN device; The TN-RAN device receives the first non-terrestrial network air interface capability request, and sends the first non-terrestrial network air interface capability request to the UE.

4. The method according to claim 2, characterized in that: The terrestrial network device includes a TN-CN device and a TN-RAN device; after receiving the second non-terrestrial network air interface capability request, the terrestrial network device sends the first non-terrestrial network air interface capability request to the UE, specifically including: The TN-CN device receives the second non-terrestrial network air interface capability request, and sends the second non-terrestrial network air interface capability request to the TN-RAN device; The TN-RAN device receives the second non-terrestrial network air interface capability request, and sends the first non-terrestrial network air interface capability request to the UE.

5. The method according to claim 1, characterized in that The terrestrial network device includes a TN-RAN device; before the UE receives the first non-terrestrial network air interface capability request, the method further includes: After the UE registers with the NTN-CN device through the TN-RAN device, the NTN-CN device sends a second non-terrestrial network air interface capability request to the TN-RAN device, where the second non-terrestrial network air interface capability request is used by the NTN-CN device to obtain NTN air interface capability information of the UE; After receiving the second non-terrestrial network air interface capability request, the TN-RAN device sends the first non-terrestrial network air interface capability request to the UE.

6. The method according to any one of claims 1 to 5, characterized in that The ground network device sends the second non-ground network air interface capability message to the NTN-CN device, specifically including: The terrestrial network device sends the second non-terrestrial network air interface capability message to the NTN-CN device in response to the first non-terrestrial network air interface capability message.

7. The method according to claim 6, characterized in that The first non-terrestrial network air interface capability message is a user equipment capability information UE Capability Information message, and the second non-terrestrial network air interface capability message is a user equipment capability information indication UE Capability Infor Indication message.

8. The method according to claim 1, characterized in that The terrestrial network device includes a TN-CN device; before the UE receives the first non-terrestrial network air interface capability request, the method further includes: After the UE registers with the TN-CN device through the terrestrial network device, the terrestrial network device sends the first non-terrestrial network air interface capability request to the UE.

9. The method according to claim 8, characterized in that The sending, by the terrestrial network device, the first non-terrestrial network air interface capability request to the UE specifically includes: After the UE registers with the TN-CN device through the ground network device, the UE sends a first capability change message to the TN-CN device, where the first capability change message is used to indicate a change in the NTN air interface capability of the UE; The TN-CN device sends a second non-terrestrial network air interface capability request to the TN-RAN device in response to the first capability change message; The TN-RAN device sends the first non-terrestrial network air interface capability request to the UE in response to the second non-terrestrial network air interface capability request; or, The TN-CN device sends the first non-terrestrial network air interface capability request to the UE through the TN-RAN device in response to the first capability change message.

10. The method according to claim 9, characterized in that The first capability change message is a second mobility registration request message, and the second mobility registration request message includes a parameter for indicating a change in the NTN air interface capability of the UE; or the first capability change message is a user equipment capability release command message.

11. The method according to any one of claims 8 to 10, characterized in that: The method further comprises: After the NTN-CN device receives the first mobility registration request message, sending a first capability synchronization message to the TN-CN device, where the first capability synchronization message is used to obtain the NTN air interface capability information of the UE from the TN-CN device; The ground network device sends the second non-ground network air interface capability message to the NTN-CN device, specifically including: The TN-CN device sends the second non-terrestrial network air interface capability message to the NTN-CN device in response to the first capability synchronization message.

12. The method according to any one of claims 1 to 11, characterized in that The sending the NTN air interface capability information of the UE to the NTN-RAN device specifically includes: The NTN-CN device sends an initial context setup request message to the NTN-RAN device, where the initial context setup request message includes the NTN air interface capability information of the UE.

13. The method according to any one of claims 1 to 12, characterized in that The first non-terrestrial network air interface capability request is a user equipment capability query UE capability enquiry (NTN) message, and the second non-terrestrial network air interface capability request is a non-terrestrial network air interface capability information request NTN capability info request.

14. The method according to any one of claims 1 to 13, characterized in that The NTN air interface capability information includes carriers supported by the UE, antenna polarization directions of the UE, maximum transmit power of the UE, and duplex mode of the UE.

15. A capability synchronization method, characterized in that: Applied to user equipment UE, characterized in that the method comprises: The UE receives a first non-terrestrial network air interface capability request sent by a terrestrial network device, where the first non-terrestrial network air interface capability request is used to obtain NTN air interface capability information of the UE; After receiving the first non-terrestrial network air interface capability request, the UE sends a first non-terrestrial network air interface capability message to the terrestrial network device, where the first non-terrestrial network air interface capability message includes the NTN air interface capability information of the UE; After searching for the non-terrestrial network NTN, the UE sends a mobility registration request message to the core network NTN-CN device of the non-terrestrial network. The mobility registration request message is used to trigger the NTN-CN device to send the NTN air interface capability information of the UE to the NTN-RAN device.

16. The method according to claim 15, characterized in that: Before the UE receives the first non-terrestrial network air interface capability request sent by the terrestrial network device, the method further includes: The UE registers with the NTN-CN device through the ground network device.

17. The method according to claim 15, characterized in that: Before the UE receives the first non-terrestrial network air interface capability request sent by the terrestrial network device, the method further includes: The UE is registered with the TN-CN device.

18. The method according to any one of claims 15 to 17, characterized in that: Before the UE receives the first non-terrestrial network air interface capability request sent by the terrestrial network device, the method further includes: The UE sends a first capability change message to the TN-CN device, where the first capability change message is used to indicate that the NTN air interface capability of the UE has changed.

19. A capability synchronization method, characterized in that: The core network NTN-CN device applied to the non-terrestrial network is characterized in that the method comprises: The NTN-CN device sends a first non-terrestrial network air interface capability request to the user equipment UE through the terrestrial network device, where the first non-terrestrial network air interface capability request is used to obtain NTN air interface capability information of the UE; The NTN-CN device receives, through the terrestrial network device, a first non-terrestrial network air interface capability message sent by the UE, where the first non-terrestrial network air interface capability message includes NTN air interface capability information of the UE; After receiving the first mobility registration request message sent by the UE, the NTN-CN device sends the NTN air interface capability information of the UE to the radio access network NTN-RAN device of the non-terrestrial network, where the first mobility registration request message is used for the UE to register with the NTN-CN device.

20. The method according to claim 19, characterized in that Before the NTN-CN device sends the first non-terrestrial network air interface capability request to the UE through the terrestrial network device, the method further includes: The NTN-CN device accepts the initial registration request of the UE through the ground network device.

21. The method according to claim 19 or 20, characterized in that The NTN-CN device sends a first non-terrestrial network air interface capability request to the UE through the terrestrial network device, specifically including: The NTN-CN device receives, through the ground network device, a first capability change message sent by the UE, where the first capability change message is used to indicate that the NTN air interface capability of the UE has changed; In response to the first capability change message, the NTN-CN device sends the first non-terrestrial network air interface capability request to the UE through the terrestrial network device.

22. A capability synchronization method, characterized in that: Applied to non-terrestrial network equipment NTN-CN, characterized in that the method comprises: After receiving the first mobility registration request message sent by the user equipment UE, the NTN-CN device sends a first capability synchronization message to the core network TN-CN device of the ground network, where the first capability synchronization message is used to obtain the NTN air interface capability information of the UE from the TN-CN device; The NTN-CN device receives a first non-terrestrial network air interface capability message sent by the TN-CN device, where the first non-terrestrial network air interface capability message includes NTN air interface capability information of the UE; The NTN-CN device sends the NTN air interface capability information of the UE to a radio access network NTN-RAN device of a non-terrestrial network.

23. A capability synchronization method, characterized in that: A core network TN-CN device applied to a terrestrial network, characterized in that the method comprises: The TN-CN device sends a first non-terrestrial network air interface capability request to the user equipment UE, where the first non-terrestrial network air interface capability request is used to obtain NTN air interface capability information of the UE; The TN-CN device receives a first non-terrestrial network air interface capability message sent by the UE, where the first non-terrestrial network air interface capability message includes NTN air interface capability information of the UE; The TN-CN device sends a second non-terrestrial network air interface capability message to a core network NTN-CN device of the non-terrestrial network, where the second non-terrestrial network air interface capability message includes NTN air interface capability information of the UE.

24. The method according to claim 23, characterized in that The TN-CN device sends a first non-terrestrial network air interface capability request to the user equipment UE, specifically including: The TN-CN device receives a second non-terrestrial network air interface capability request sent by the NTN-CN device; The TN-CN device sends the first non-terrestrial network air interface capability request to the UE in response to the second non-terrestrial network air interface capability request.

25. The method according to claim 23, characterized in that The TN-CN device sends a first non-terrestrial network air interface capability request to the user equipment UE, specifically including: After accepting the initial registration request of the UE, the TN-CN device sends the first non-terrestrial network air interface capability request to the UE.

26. The method according to claim 25, characterized in that The TN-CN device sends a second non-terrestrial network air interface capability message to the core network NTN-CN device of the non-terrestrial network, specifically including: The TN-CN device receives a first capability synchronization message sent by the NTN-CN device; The TN-CN device sends the second non-terrestrial network air interface capability message to the NTN-CN device in response to the first capability synchronization message.

27. The method according to any one of claims 23 to 26, characterized in that Before the TN-CN device sends the first non-terrestrial network air interface capability request to the user equipment UE, the method further includes: The TN-CN device receives a first capability change message sent by the UE, where the first capability change message is used to indicate that an NTN air interface capability of the UE has changed.

28. A capability synchronization method, characterized in that: A TN-RAN device for a terrestrial network, wherein the method comprises: The TN-RAN device sends a first non-terrestrial network air interface capability request to the user equipment UE, where the first non-terrestrial network air interface capability request is used to obtain NTN air interface capability information of the UE; The TN-RAN device receives a first non-terrestrial network air interface capability message sent by the UE, where the first non-terrestrial network air interface capability message includes NTN air interface capability information of the UE; The TN-RAN device sends a second non-terrestrial network air interface capability message to a core network NTN-CN device of a non-terrestrial network or a core network TN-CN device of a terrestrial network, where the second non-terrestrial network air interface capability message includes the NTN air interface capability information of the UE.

29. An electronic device, characterized in that: include: one or more processors and one or more memories; The one or more memories are coupled to one or more processors, and the one or more memories are used to store computer executable programs. When the one or more processors execute the computer executable programs, the electronic device executes the method described in any one of claims 15-18, 19-21, 22, 23-27 or 28.

30. A computer-readable storage medium storing a computer program, characterized in that: When the computer program runs on a processor of an electronic device, the electronic device is caused to execute the method according to any one of claims 15-18, 19-21, 22, 23-27 or 28.

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