Non-ground network communication method and device

Abstract

The embodiment of the invention provides a non-ground network communication method and device which are applied to an NTN scene, in the communication method, based on an NTN storage and forwarding mechanism, a network device can send a first message to a terminal, the first message is used for indicating that the network device located on a high-altitude platform such as a satellite does not cache downlink data of the terminal in a coverage area of the network device, and the network device can send the downlink data to the terminal. According to the embodiment of the invention, the terminals do not monitor paging messages or do not establish RRC connection, so that the terminals can save power consumption in a store-and-forward scene of NTN communication.

Description

Technical Field

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

[0002] Satellite networks are a hot research topic in the world today. Satellite communication technology has become increasingly mature. For example, non-terrestrial networks (NTNs) use the radio frequency network or network segment on satellites to achieve communication, which can provide a wider coverage. However, terminal listening to satellite signals consumes a lot of power. Therefore, how to save power consumption for terminal devices in satellite coverage scenarios is an urgent problem to be solved. Summary of the Invention

[0003] This application provides a non-terrestrial network communication method and apparatus that enables terminals to save power in NTN communication store-and-forward scenarios.

[0004] Firstly, a communication method is provided for NTN communication, including...

[0005] Receive a first message, the first message containing at least one of the following:

[0006] Indicates that the first network device does not cache downlink data from terminals located in the first area; or,

[0007] Instruct the first network device to cache downlink data from terminals located in the third area; or,

[0008] Indicates the first group number of the terminal corresponding to the downlink data cached by the first network device;

[0009] The first network device is deployed on a satellite;

[0010] Based on the first message, either not to listen for some or all of the paging messages from the first network device, or not to establish the first connection; or...

[0011] Based on the first message, listen for paging messages from the first network device, or establish a first connection.

[0012] In the above scheme, the network equipment is deployed on a high-altitude platform, such as a satellite, and sends a first message instructing the network equipment on the satellite whether to cache data from terminals in the coverage area. When the satellite can send the first message to the terminal, the service link must be in a connected state. However, in a store-and-forward scenario, when the service link is connected, the power supply link must be disconnected. Therefore, for a period of time after the terminal receives the first message, no new data will reach the network equipment on the satellite. Thus, the terminal can, under appropriate conditions, choose not to listen for paging messages or not to establish the first connection, thereby saving power consumption.

[0013] Optionally, the coverage area can be an area covered by the network device in the past period of time, an area to be covered in the future period of time, or an area currently being covered; all of the above-mentioned periods of time can be set.

[0014] In some possible implementations, the communication method further includes, based on the first message, performing one of the following actions:

[0015] When it is determined that the second region belongs to a subset of the first region, the following steps are taken: either not to listen to some or all of the paging messages of the first network device, or not to establish the first connection.

[0016] When it is determined that the second region is not a subset of the first region, the process of listening to the paging message of the first network device is executed, or a first connection is established.

[0017] When it is determined that the second region overlaps with the third region, the process of listening to the paging message of the first network device is executed, or a first connection is established.

[0018] When it is determined that the second group number matches the first group number, the process of listening to the paging message of the first network device is executed, or the first connection is established.

[0019] If it is determined that the second group number does not match the first group number, then the following steps are taken: either not to listen to some or all of the paging messages of the first network device, or not to establish the first connection.

[0020] When it is determined that the second region overlaps with the third region and the second group number matches the first group number, the process of listening to the paging message of the first network device or establishing the first connection is executed.

[0021] If it is determined that the second region overlaps with the third region, but the second group number does not match the first group number, then the following steps are taken: either not to listen to some or all of the paging messages of the first network device, or not to establish the first connection.

[0022] If it is determined that the second region and the third region do not overlap, then the following steps are taken: either not to listen to some or all of the paging messages of the first network device, or not to establish the first connection.

[0023] Optional,

[0024] The first region includes:

[0025] The first network device covers or serves at least one tracking area, or a region of the Earth's surface, wherein the region of the Earth's surface is indicated by the region information included in the first message;

[0026] The second region includes:

[0027] The tracking area in which it is located, or a set of multiple tracking areas including the tracking area, or at least one of the locations in which it is located.

[0028] Optionally, the Earth's surface region can be defined by using latitude and longitude to indicate the center point location and adding the radius distance; or by indicating a pre-defined region; or by indicating multiple point locations to define a geometrically shaped region. This region can be the Earth's surface region corresponding to a tracking area with or without cached data (including or excluding boundaries, depending on a preset setting).

[0029] Optionally, the first message includes at least one of the first region, the third region, or the first group ID of the terminal corresponding to the cached downlink data.

[0030] In some possible implementations, the communication method further includes,

[0031] The second group number is determined based on the second message, or based on the terminal identifier (UE ID).

[0032] In other words, the group ID can be sent by the network device to the terminal, such as during the access process or the tracking area update process, or it can be determined by the terminal itself based on the terminal identifier or a pre-agreed method.

[0033] In some possible implementations, the communication method further includes, before receiving the first message,

[0034] Send a third message that requests a packet or indicates support for a packet;

[0035] Receive a second message, which includes a second group number.

[0036] Optionally, the first message further includes a duration, wherein the start time of the duration is based on a first moment and a first threshold, and the end time of the duration is based on a second moment and a second threshold, wherein the first moment is the moment when the first network device disconnects from the ground station link, and the second moment is the moment when the first network device restores the ground station link; the first threshold and the second threshold are preset time values, which can be 0 or not exist.

[0037] Optionally, the statement of not listening to some or all of the paging messages of the first network device includes at least one of the following:

[0038] Do not listen to paging messages used for data transmission from the first network device;

[0039] Upon receiving a paging message for data transmission from the first network device, a connection establishment is not triggered.

[0040] Listen for paging only once or a finite number of n times within the system information modification cycle;

[0041] Deactivate or pause the AS layer (access stratum).

[0042] Optionally, a first connection is established, including at least one of the following:

[0043] Initiate a registration process, or initiate an RRC connection establishment process, or initiate an RRC connection recovery process.

[0044] Optionally, not establishing a first connection includes at least one of the following:

[0045] The registration process, or the RRC connection establishment process, or the RRC connection recovery process will not be initiated.

[0046] Secondly, a communication method is provided for NTN communication, including:

[0047] Send a first message, the first message containing at least one of the following:

[0048] This indicates that no downlink data from terminals located in the first region is cached; or,

[0049] Instruct to cache downlink data from terminals located in the third region; or,

[0050] Indicates the first group number of the terminal corresponding to the cached downlink data;

[0051] Based on the first message, the terminal is instructed not to listen to some or all paging messages, or not to establish the first connection; or,

[0052] Based on the first message, the terminal is instructed to listen for paging messages or establish a first connection.

[0053] In the above scheme, the network equipment is deployed on a high-altitude platform, exemplified by a satellite. The network equipment can send a first message indicating whether the network equipment on the satellite has cached data from terminals in the coverage area. When the satellite can send the first message to the terminal, the service link must be connected. However, in a store-and-forward scenario, when the service link is connected, the power supply link must be disconnected. During the period the network equipment sends the first message, no new data will arrive at the network equipment on the satellite. Therefore, the network equipment can instruct the terminal not to listen for paging messages or establish a first connection under appropriate circumstances, thereby achieving the goal of saving power.

[0054] Optionally, both the first and third regions are coverage areas of the network device. These coverage areas can be areas covered by the network device in the past, areas to be covered in the future, or areas currently being covered; the time period can be set. Here, "coverage" can also be understood as providing services.

[0055] In some possible implementations, the communication method further includes:

[0056] Based on the first message, the terminal is instructed to perform one of the following actions:

[0057] When the second region is a subset of the first region, it indicates that some or all paging messages should not be listened to, or that the first connection should not be established.

[0058] When the second region is not a subset of the first region, the listener is instructed to send a paging message, or a first connection is established.

[0059] When the second region overlaps with the third region, the monitoring paging message is indicated, or a first connection is established;

[0060] When the second group number matches the first group number, it instructs the monitoring of the paging message of the first network device, or to establish the first connection;

[0061] When the second group number does not match the first group number, it indicates that some or all paging messages will not be listened to, or the first connection will not be established.

[0062] When the second region overlaps with the third region and the second group number matches the first group number, the monitoring paging message is indicated, or a first connection is established;

[0063] If the second region overlaps with the third region, but the second group number does not match the first group number, it indicates that some or all paging messages will not be listened to, or the first connection will not be established.

[0064] When the second region does not overlap with the third region, it indicates that some or all paging messages should not be listened to, or that the first connection should not be established.

[0065] Optional,

[0066] The first region includes:

[0067] At least one tracking area or region of the Earth's surface that is covered or served, wherein the region of the Earth's surface is indicated by the region information included in the first message;

[0068] The second region includes:

[0069] The tracking area where the terminal is located, or a set of multiple tracking areas including the tracking area, or at least one of the locations where the terminal is located.

[0070] Optionally, the Earth's surface region can be defined by using latitude and longitude to indicate the center point location and adding the radius distance; or by indicating a pre-defined region; or by indicating multiple point locations to define a geometrically shaped region. This region can be the Earth's surface region corresponding to a tracking area with or without cached data (including or excluding boundaries, depending on a preset setting).

[0071] Optionally, the first message includes at least one of the first region, the third region, or the first group ID of the terminal corresponding to the cached downlink data.

[0072] In some possible implementations, the communication method further includes,

[0073] The second group number is indicated based on the second message.

[0074] In other words, the group ID can be sent by the network device to the terminal, such as during the access process or the tracking area update process, or it can be determined by the terminal itself based on the terminal identifier or a pre-agreed method.

[0075] For the first region and the second region, the matching relationship between them can also be understood as a relationship such as association or equality.

[0076] In some possible implementations, the communication method further includes, before sending the first message,

[0077] Receive a third message, wherein the third message requests a packet for the terminal or instructs the terminal to support packets;

[0078] Send a second message, which includes a second group number.

[0079] Optionally, the first message further includes a duration, wherein the start time of the duration is based on a first moment and a first threshold, and the end time of the duration is based on a second moment and a second threshold, wherein the first moment is the moment when the ground station link is disconnected, and the second moment is the moment when the ground station link is restored; the first threshold and the second threshold are preset time values, which can be 0 or not exist.

[0080] Optionally, the statement of not listening to some or all paging messages includes at least one of the following:

[0081] Do not listen to paging messages used for data transmission from the first network device;

[0082] Upon receiving a paging message for data transmission from the first network device, a connection establishment is not triggered.

[0083] Listen for paging only once or a finite number of n times within the system information modification cycle;

[0084] Deactivate or pause the AS layer (access stratum).

[0085] Optionally, a first connection is established, including at least one of the following:

[0086] Initiate a registration process, or initiate an RRC connection establishment process, or initiate an RRC connection recovery process.

[0087] Optionally, not establishing a first connection includes at least one of the following:

[0088] The registration process, or the RRC connection establishment process, or the RRC connection recovery process will not be initiated.

[0089] Thirdly, an electronic device is provided, which is a communication apparatus having the function of implementing any of the above aspects. The function can be implemented by hardware or by hardware executing corresponding software. The hardware or software includes one or more modules or units corresponding to the above functions. For example, a transceiver module or unit, a processing module or unit, an acquisition module or unit, etc.

[0090] Fourthly, embodiments of this application provide a communication device, including: a memory and a processor, wherein the memory is used to store a computer program; and the processor is used to cause the communication device to execute the communication method described in any one of the above aspects when the computer program is invoked.

[0091] Fifthly, embodiments of this application provide a chip system including a processor coupled to a memory, the processor executing a computer program stored in the memory to implement the communication method described in any of the above aspects.

[0092] The chip system can be a single chip or a chip module composed of multiple chips.

[0093] Sixthly, embodiments of this application provide a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the communication method described in any of the above aspects.

[0094] In a seventh aspect, embodiments of this application provide a computer program product that, when run on a communication device, causes the communication device to execute the communication method described in any of the above aspects.

[0095] It is understood that the beneficial effects of aspects three through seven mentioned above can be found in the relevant descriptions of the above aspects, and will not be repeated here. Attached Figure Description

[0096] Figure 1(a) is a schematic diagram of the area coverage provided in an embodiment of this application.

[0097] Figure 1(b) is a schematic diagram of another area coverage provided by an embodiment of this application.

[0098] Figure 2(a) is an LTE paging flowchart provided in an embodiment of this application.

[0099] Figure 2(b) is a flowchart of the NR paging process provided in an embodiment of this application.

[0100] Figure 2(c) is a flowchart of the RRC connection establishment process provided in the embodiment of this application.

[0101] Figure 2(d) is a flowchart of the RRC connection recovery process provided in the embodiment of this application.

[0102] Figure 2(e) is another RRC connection recovery flowchart provided in the embodiments of this application.

[0103] Figure 3(a) is a schematic diagram of the NTN store-and-forward scenario provided in the embodiments of this application.

[0104] Figure 3(b) is another schematic diagram of the NTN store-and-forward scenario provided in the embodiments of this application.

[0105] Figure 4(a) is another schematic diagram of an NTN store-and-forward scenario provided by an embodiment of this application.

[0106] Figure 4(b) is another schematic diagram of an NTN store-and-forward scenario provided by an embodiment of this application.

[0107] Figure 5 This is a schematic diagram of another area coverage provided in the embodiments of this application.

[0108] Figure 6 This is a schematic diagram of another area coverage provided in the embodiments of this application.

[0109] Figure 7 This is a schematic diagram of a communication device provided in an embodiment of this application.

[0110] Figure 8 This is a schematic diagram of another communication device provided in an embodiment of this application. Detailed Implementation

[0111] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0112] The technical solutions of this application can be applied to various communication systems, such as: Long Term Evolution (LTE) systems, Advanced Long Term Evolution (LTE-A) systems, LTE Frequency Division Duplex (FDD) systems, LTE Time Division Duplex (TDD) systems, Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX) systems, next-generation communication systems (e.g., fifth-generation (5G) systems), converged systems of multiple access systems, or evolved systems; the three major application scenarios of 5G mobile communication systems: enhanced mobile broadband (eMBB), ultra-reliable low-latency communication (URLLC), and enhanced machine-type communication (eMTC); or new communication systems that will emerge in the future. The technical solutions provided in this application can also be applied to future communication systems, such as sixth-generation mobile communication systems. This application does not limit these applications.

[0113] The technical solutions provided in this application can also be applied to machine-type communication (MTC), long-term evolution-machine (LTE-M) technology, device-to-device (D2D) networks, machine-to-machine (M2M) networks, Internet of Things (IoT) networks, or other networks. Among these, IoT networks may include, for example, vehicle-to-everything (V2X) networks. The communication methods in V2X systems are collectively referred to as vehicle-to-X (V2X), where X can represent anything. For example, V2X may include vehicle-to-vehicle (V2V) communication, vehicle-to-infrastructure (V2I) communication, vehicle-to-pedestrian (V2P) communication, or vehicle-to-network (V2N) communication, etc.

[0114] The network device in this application embodiment can also be called a radio access network (R)AN. The R)AN can manage radio resources, provide access services for terminal devices, and complete the forwarding of terminal device data between the terminal device and the core network. The R)AN can also be understood as a base station in the network, which is a device deployed in the radio access network to provide wireless communication functions for mobile stations (MS).

[0115] For example, the access network device in this application embodiment can be any kind of communication device with wireless transceiver function for communicating with terminal devices. The access network equipment includes, but is not limited to: evolved NodeB (eNB), radio network controller (RNC), Node B (NB), base station controller (BSC), base transceiver station (BTS), home evolved NodeB (HeNB, or home Node B, HNB), baseband unit (BBU), access point (AP), wireless relay node, wireless backhaul node, transmission point (TP), or transmission and reception point (TRP) in a wireless fidelity (WiFi) system. It can also be a gNB in ​​a 5G system, or a transmission point (TRP or TP), one or a group of antenna panels (including multiple antenna panels) of a base station in a 5G system, or a network node constituting a gNB or transmission point, such as a baseband unit (BBU) or a distributed unit (DU). It is understood that all or part of the functions of the access network device in this application can also be implemented through software functions running on hardware, or through virtualization functions instantiated on a platform (such as a cloud platform).

[0116] In another network architecture, access network equipment may include centralized unit (CU) nodes, distributed unit (DU) nodes, or RAN equipment comprising both CU and DU nodes. This RAN equipment, including CU and DU nodes, separates the protocol layers of the gNB in ​​the NR system. Some protocol layer functions are centrally controlled by the CU, while the remaining partial or complete protocol layer functions are distributed across the DUs, which are then centrally controlled by the CU. The centralized unit (CU) can also be divided into a control plane (CU-CP) and a user plane (CU-UP). The CU-CP handles control plane functions, primarily including the RRC and the corresponding PDCP (PDCP-C). PDCP-C is mainly responsible for control plane data encryption / decryption, integrity protection, and data transmission. The CU-UP handles user plane functions, primarily including SDAP and the corresponding PDCP (PDCP-U). SDAP is mainly responsible for processing core network data and mapping flows to bearers. PDCP-U is mainly responsible for data plane encryption / decryption, integrity protection, header compression, sequence number maintenance, and data transmission. The CU-CP and CU-UP are connected via an E1 interface. CU-CP represents the gNB connecting to the core network via the NG interface. It connects to the DU via the F1 interface control plane (F1-C). CU-UP connects to the DU via the F1 interface user plane (F1-U). Alternatively, PDCP-C may also be located within CU-UP. RAN equipment is responsible for air interface-side radio resource management, Quality of Service (QoS) management, data compression, and encryption. AN equipment provides access services to terminal devices, thereby forwarding control signals and user data between the terminal devices and the core network.

[0117] The terminal device in the embodiments of this application may also be referred to as user equipment (UE), terminal, access terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, wireless communication device, user agent, or user apparatus. The terminals in the embodiments of this application may be mobile phones, tablets, computers with wireless transceiver capabilities, virtual reality (VR) terminals, augmented reality (AR) terminals, wireless terminals in industrial control, wireless terminals in self-driving, wireless terminals in remote medical care, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, cellular phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), handheld devices with wireless communication capabilities, computing devices or other processing devices connected to a wireless modem, in-vehicle devices, wearable devices, terminals in 5G networks, or terminals in future evolved networks, etc.

[0118] Wearable devices, also known as wearable smart devices, are a general term for devices that utilize wearable technology to intelligently design and develop everyday wearables, such as glasses, gloves, watches, clothing, and shoes. Wearable devices are portable devices worn directly on the body or integrated into the user's clothing or accessories. Wearable devices are not merely hardware devices; they achieve powerful functions through software support, data interaction, and cloud interaction. Broadly defined, wearable smart devices include those with comprehensive functions, large sizes, and the ability to perform complete or partial functions without relying on a smartphone, such as smartwatches or smart glasses. They also include devices focused on a specific application function that require the use of other devices, such as smart bracelets and smart jewelry for vital sign monitoring.

[0119] In this embodiment of the application, the communication device used to implement the function of the network device can be a network device, a network device with base station functions, or a device that can support the network device to implement the function, such as a chip system, which can be installed in the network device.

[0120] Non-terrestrial networks refer to networks or network segments that utilize the radio frequency (RF) of satellite, unmanned aerial system (UAS) platforms, or high-altitude platforms. The most typical non-terrestrial network provides communication services via satellite.

[0121] Satellite communication boasts advantages such as wide coverage, long communication distance, high reliability, high flexibility, and high throughput. In particular, it is unaffected by geographical environment, climate conditions, and natural disasters, giving it excellent development prospects. Currently, satellite communication is widely used in aviation, maritime, and military communications. Introducing satellites into future 5th-generation (5G) mobile networks can provide communication services to areas difficult to cover with traditional terrestrial networks, such as oceans and forests. It can also enhance the reliability of 5G communication, providing more stable and higher-quality communication services for users on trains, airplanes, and other modes of transportation. Furthermore, it can provide more data transmission resources and support a larger number of connections. Thanks to the current concept of "anytime, anywhere" communication, the status of satellite communication networks will be further enhanced in the future.

[0122] Generally speaking, the higher the satellite's orbit, the larger its coverage area, but the longer the communication latency. Satellite orbits are generally classified by altitude into Low Earth Orbit (LEO), Medium Earth Orbit (MEO), and Geostationary Orbit (GEO). Non-Geosynchronous orbit (NGSO) includes Low Earth Orbit (LEO) at altitudes of approximately 300 km to 1500 km and Medium Earth Orbit (MEO) at altitudes of approximately 7000 km to 25000 km. NTN cells are classified into fixed cells (or geostationary cells), quasi-fixed cells, and mobile cells.

[0123] A fixed cell refers to a beam, cell, or satellite that provides fixed coverage to a specific geographical area. For example, geostationary satellites can provide fixed cells.

[0124] Quasi-Geostationary: Also known as quasi-fixed cell, a beam, cell, or satellite covers a geographic area for a limited time and a different geographic area at another time (e.g., the case of an NGSO (Non-Geosynchronous orbit) satellite generating a steerable beam), as shown in Figure 1(a); Satellite 1 is at three different positions on its orbit at times T1, T2, and T3. However, Satellite 1 can adjust its antenna angle or satellite attitude to ensure that it always covers geographic area 1 within a possible range (e.g., if it is on the other side of the Earth relative to geographic area 1, it will no longer be able to provide service due to the angle).

[0125] Earth Movement: The coverage area of ​​a beam, cell, or satellite slides across the Earth's surface (e.g., the case of an NGSO satellite producing a fixed or non-steerable beam), as shown in Figure 1(b). Satellite 1 is at three different positions in its orbit at times T1, T2, and T3. Due to the change in position, these three times correspond to covering three different geographical regions 1, 2, and 3, respectively. It is easy to understand that these three geographical regions can be continuous and overlapping.

[0126] It could also be a combination of the above, with the aim of covering some population or business hotspots.

[0127] This invention applies to a scenario called Mobile Terminated Data Transport (MT), specifically referring to the process where the core network (CN) receives downlink data from a connectionless terminal and transmits the downlink data to the terminal. The process involves the core network paging the terminal; after paging, the terminal reconnects to the network, and the core network sends the data to the terminal. Because the core network elements involved in the LTE and NR protocols differ, the MT data transmission process may vary slightly depending on whether the terminal accesses a 4G or 5G core network.

[0128] Figure 2(a) illustrates the 4G paging process. After the SGW receives downlink data from the network side, if the terminal is not in a connected state, the SGW triggers the sending of a downlink data notification message to the MME. The MME replies to the SGW with a Downlink Data Notification Ack message, confirming receipt of the downlink data notification. Simultaneously, the MME sends a paging message to each base station belonging to the tracking area where the terminal last camped. This paging message may include the terminal paging identifier, TAI (Tracking Area Identity) information, etc. The TAI is used to uniquely identify a tracking area (in the NTN scenario, the tracking area can also be a fixed area on the Earth's surface). The TAI may include PLMN and TAC (Tracking Area Code). For example, if the MME stores the terminal's last camped tracking areas as Tracking Area 1 and Tracking Area 2, where Tracking Area 1 corresponds to base station 1 and Tracking Area 2 corresponds to base station 2, then the MME needs to send the terminal's paging message to both base station 1 and base station 2. The base station determines the timing and target terminals for paging based on the paging message from the MME. The base station then sends a paging message containing terminal identification information. The terminal can calculate the time of the paging occasion (PO) based on its own IMSI (International Mobile Subscriber Identity). During the PO time, the terminal detects the paging PDCCH (including the paging DCI). The base station can include paging messages for multiple terminals in a single paging message, and each terminal will have a separate PagingRecord.

[0129] When a terminal detects a paging PDCCH at the PO (Positioning Point), it will receive a paging PDSCH at the location scheduled by that paging PDCCH. The paging PDSCH contains one or more paging records, each containing at least one UE ID. The UE ID indicates the specific paging terminal and may include an International Mobile Subscriber Identity (IMSI) or a 5G-S Temporary Mobile Subscriber Identity (5G-S-TMSI). If the UE-Identity contained in the PagingRecord matches one of the terminal identifiers assigned by the upper or higher layer, the terminal can confirm that it has been paging, thus triggering an RRC connection establishment or RRC connection recovery process. Alternatively, if the UE-Identity contained in the PagingRecord matches one of the terminal identifiers assigned by the upper or higher layer, the UE-Identity is forwarded to the higher layer, which, in response, triggers an RRC connection establishment or RRC connection recovery process. This downlink service data-triggered process can also be called the MT (Mobile Terminal) data transmission procedure.

[0130] Figure 2(b) illustrates the 5G paging process. There is downlink service data from a non-connected terminal. According to the NR protocol, this downlink data can be cached in the UPF or not. The UPF uses the Downlink Data Notification message from step 2a to notify the SMF. The SMF then uses the Enable UE Reachability Request message from step 2c to notify the AMF that there is downlink data. Subsequently, in step 3, the AMF sends a paging message to each base station belonging to the tracking area registered by the terminal. This paging message may contain the terminal paging identifier, TAI (Tracking Area Identity) information, etc. The TAI is used to uniquely identify a tracking area. The TAI may contain the PLMN and TAC (Tracking Area Code). If the AMF stores tracking areas registered by the terminal as Tracking Area 1 and Tracking Area 2, where Tracking Area 1 corresponds to base station 1 and Tracking Area 2 corresponds to base station 2, then the AMF needs to send paging messages to both base station 1 and base station 2. The base station determines the timing of paging and the terminal to be paging based on the AMF paging message. The base station then sends a paging message containing terminal identification information. Similar to 4G, the terminal can calculate the time of occurrence of the paging occasion (PO) based on its own identifier (5G-S-TMSI). The terminal detects the paging PDCCH (including the paging DCI) within the PO time. The base station can include paging messages for multiple terminals in a single paging message, with each terminal having a separate PagingRecord.

[0131] For NR's MT data transmission process, if the detected paging PDCCH indicates that the scheduling information is a paging message, then the paging PDSCH will be received at the location scheduled by that paging PDCCH. The paging PDSCH contains one or more paging records, each containing at least one UE ID, which indicates the specific paging terminal. If the UE-Identity contained in the PagingRecord matches one of the terminal identifiers assigned by the upper layer or higher layer, the terminal can confirm that it has been paged, thereby triggering the RRC connection establishment process or the RRC connection recovery process. Alternatively, if the UE-Identity contained in the PagingRecord matches one of the terminal identifiers assigned by the upper layer or higher layer, the UE-Identity is forwarded to the higher layer, and the higher layer, in response, triggers the RRC connection establishment process or the RRC connection recovery process.

[0132] Figure 2(c) illustrates the RRC connection establishment process. 1. The UE sends an RRC connection establishment request to the base station. This request includes the UE's identification information. Optionally, the RRC connection establishment request may also include RRC connection establishment reason information, indicating that the UE is requesting the RRC connection to receive store-and-forward data. 2. The base station sends an RRC connection establishment message to the UE. This message includes radio resource configuration information (MAC layer and / or physical layer configuration information). 3. The UE sends an RRC connection establishment completion message to the base station, confirming that the RRC connection establishment was successfully completed.

[0133] Figure 2(d) illustrates the RRC connection recovery process. 1. The UE sends an RRC connection recovery request to the base station. The RRC connection recovery request includes a recovery ID (for base stations connected to the 4G core network) or an I-RNTI (for base stations connected to the 5G core network). (I-RNTI, Inactive RNTI, Temporary Identifier for Inactive Radio Network). Optionally, it includes RRC connection recovery reason information, indicating that the UE requests the recovery of the RRC connection to receive store-and-forward data. 2a. The base station sends an RRC connection recovery message to the UE, which is used to recover the RRC connection. If the base station cannot recover the UE context or cannot obtain the UE context from other base stations, the base station sends an RRC connection establishment message to the UE. 3a. The UE sends an RRC connection recovery completion message to the base station, which is used to confirm that the RRC connection recovery was successfully completed. If, after step 1, the message sent by the base station is not an RRC connection recovery message, as shown in Figure 2(e), 2b. the UE receives the RRC connection establishment message, then 3b. the UE sends the RRC connection establishment completion message. In other words, there are different follow-up procedures for RRC connection recovery requests.

[0134] Another type of paging mechanism is system-level paging. Base stations can include changes in system information and / or provide ETWS (Earthquake and Tsunami Warning System) or CMAS (Commercial Mobile Alert Service) notifications in these paging messages. These paging messages differ from ordinary paging messages sent to terminals for downlink data; they are initiated to all terminals within the base station's coverage area, and all terminals will listen for and receive them. Therefore, they are considered system-level broadcast paging. In certain situations, such as changes in base station system information, terminals need to use system-level paging messages to retrieve the necessary changed system information, or ETWS / CMAS notifications.

[0135] Currently, NTN needs to support store-and-forward scenarios. Specifically, this scenario means that the service link and the feeder link (feeder link) cannot exist simultaneously, and the satellite must possess the functions of a base station or part of a base station (here, "satellite" is used for a unified explanation; in practice, it could also refer to various devices in the NTN scenario, such as drones and high-altitude platforms, and the same applies throughout). As shown in Figures 3(a) and 3(b), when satellite 1 is in orbit, at time T1, it will disconnect from the service link of the terminal while connecting to the feeder link of the ground station. At time T2, it will connect to the service link of the terminal but disconnect from the feeder link of the ground station. The system during the T1-T2 period is a typical NTN store-and-forward scenario. In other words, in the store-and-forward scenario, the core network-base station-terminal path, essential for traditional wireless transmission, is not always in an end-to-end connected state. Simply put, when there is a link between the core network and the base station (feeder link connected), there is no link between the base station and the terminal (service link disconnected); and when there is a link between the base station and the terminal (service link connected), there is no link between the core network and the base station (feeder link disconnected). Due to the unique characteristics of store-and-forward scenarios, the satellite buffers downlink data to be sent to the terminal when the service link is disconnected but the feeder link is connected. Once the service link between the base station and the terminal is established, the base station pagees the terminal, and the downlink data is sent after the terminal reconnects. In NTN communication, the terminal's power consumption is significantly higher than in ordinary terrestrial communication scenarios because it needs to communicate with the satellite. The high power consumption of terminals in NTN scenarios has always been a problem that needs to be solved. Analyzing the characteristics of store-and-forward scenarios, the following situation arises: if the satellite base station does not receive downlink data from the terminal during the feeder link connection period, then it will also not receive downlink data during the terminal's service link connection period. This is because, as mentioned above, the service link and feeder link cannot be simultaneously connected, meaning that during the terminal's service link connection period, the feeder link is disconnected, and therefore no downlink data will arrive. Based on this, power consumption can be reduced by decreasing the terminal's paging monitoring time, leading to the specific embodiments involved in this invention below.

[0136] As shown in Figure 4(a), Satellite 1 will disconnect its feeder link after time T1. At this time, Satellite 1 has no cached downlink data. At time T2, as shown in Figure 4(b), the satellite regains its feeder link. That is, during the time interval T1-T2, at least one area to be covered by the base station on Satellite 1 will not have cached data. In this case, the system process includes:

[0137] S101, Satellite 1 (base station) sends an indication message indicating that Satellite 1 has no cached data, or that it has no stored downlink data. Alternatively, it may indicate that Satellite 1 has cached data / stored downlink data.

[0138] Optionally, the area here is at least one tracking area covered or served by Satellite 1, or at least one area of ​​the Earth's surface covered or served.

[0139] Optionally, the indication information may indicate the entire tracking area covered or served, or the entire Earth's surface area covered or served. In this case, it is further optional that the indication information does not carry area information, defaulting to indicating the entire area, or indicating the entire area is involved through a flag bit.

[0140] Optionally, the notification information can be sent via unicast or broadcast, and all terminals within the coverage or service area will expect to receive this notification information.

[0141] In NTN, there are several different uplink architectures, and the following situations apply to these different architectures.

[0142] a) Base station only: Optimize transmission for control plane (CP) and user plane (UP), and store data at the base station, i.e., on satellite 1. In this case, the base station determines that no downlink data is cached.

[0143] b) Base station and part or all of the MME / AMF are uploaded to satellite:

[0144] i.CP optimizes transmission, downlink data is sent to MME / AMF, and MME / AMF notifies the base station that no downlink data is cached;

[0145] ii.UP optimizes transmission; when downlink data reaches the base station, the base station determines that no downlink data has been cached.

[0146] c) Base station and (partial) core network CN uplink:

[0147] i.CP optimized transmission: downlink data is stored in S-GW / UPF, S-GW sends an indication to the base station via MME, and UPF sends an indication to the base station via AMF, or S-GW / UPF directly indicates to the base station that no downlink data is cached;

[0148] ii.UP optimized transmission: downlink data is in S-GW / UPF, S-GW instructs the base station via MME, and UPF instructs the base station via AMF, or S-GW / UPF directly instructs the base station that no downlink data is cached.

[0149] Optionally, the coverage area indicated by the indication information can be an area covered by satellite 1 in the past, an area to be covered in the future, or an area currently being covered; the time period can be set.

[0150] S102, after receiving the indication information, the terminal within the coverage area of ​​satellite 1 determines that satellite 1 is not caching the terminal's downlink data. The terminal then stops listening for paging messages from satellite 1 and enters a mode where it does not listen for paging messages. Alternatively, the terminal may not listen for paging messages from satellite 1 used for data transmission, or the terminal may not listen for paging messages from satellite 1 and / or not receive downlink data, or satellite 1 may choose not to send a system paging message in this situation. Alternatively, the terminal may not establish an RRC connection, for example, by not initiating a registration process, not initiating an RRC connection establishment process, not initiating an RRC connection recovery process, or not initiating an attach process.

[0151] Specifically, the terminal can not listen to paging messages in the following ways, which can also be called the non-listening-to-paging-message ...

[0152] a) After receiving the indication information, the terminal determines that there is no downlink data from satellite 1. The terminal will only listen for paging once within the system information modification period, or a preset finite number of times n (n is a positive integer). During other paging opportunities within the system information modification period, the terminal will not listen for paging. Correspondingly, the base station can extend the system information modification period as much as possible to allow the terminal to save power.

[0153] (b) After receiving the indication information, if the terminal determines that there is no downlink data from satellite 1, the terminal can deactivate or suspend the access stratum (AS). The terminal can save the AS-related configuration information; or keep all running timers running, but not perform any idle mode tasks, such as measurements. These timers include a terminal location information validity period timer (if this timer expires, the terminal's location information is considered invalid or inaccurate); a satellite ephemeris information or satellite auxiliary information validity period timer (if this timer expires, the satellite auxiliary information is considered invalid or inaccurate); or not trigger a connection establishment / random access process after listening to a paging message for data transmission; or stop all listening and paging; or keep running timers running while not performing at least one of the following idle mode tasks: The terminal performs all idle mode tasks before or after (preset time) when satellite 1 or its serving cell stops coverage / service. Alternatively, the terminal performs all idle mode tasks when it needs uplink data.

[0154] In another possible scenario, the system flow includes:

[0155] S201, Satellite 1 sends an indication message indicating that there is cached data in part or all of the area covered or served by the base station on Satellite 1. The indicated area is called the third area.

[0156] Optionally, the third region here is at least one tracking area covered or served by Satellite 1, or part or all of the Earth's surface covered or served.

[0157] Optionally, the area indication information indicates that there is data in the tracking area currently broadcast by the base station on satellite 1.

[0158] Optionally, when indicating a region on the Earth's surface, a region can be defined by using latitude and longitude to indicate the center point location, plus a radius distance; or by indicating a pre-defined region; or by indicating multiple point locations to define a geometrically shaped region. Here, the region refers to the Earth's surface area corresponding to a data-tracked region.

[0159] Optionally, the region can also indicate a first region where no data is cached. In this case, the indication information includes at least one of the first region and the third region.

[0160] In NTN, there are several different uplink architectures, and the following situations apply to these different architectures.

[0161] a) Base station only: Optimize transmission for CP and UP, and store data at the base station, that is, store it on satellite 1 (all data is sent to the base station at time T1, and the power supply link is disconnected at time T1). In this case, the base station can determine the tracking area corresponding to the terminal to which the data is to be sent.

[0162] b) Base station and part or all of the MME / AMF are uploaded to satellite:

[0163] i. CP optimized transmission: all data at time T1 is sent to MME / AMF, and MME / AMF notifies the base station of the tracking area of ​​the terminal corresponding to the [T1,T2] time data;

[0164] ii.UP optimizes transmission. At time T1, all data arrives at the base station. The MME / AMF knows the tracking area corresponding to these data. The MME / AMF notifies the base station of the tracking area where the terminal corresponding to the time data [T1, T2] is located.

[0165] c) If the base station is connected to (partially) the core network CN:

[0166] i. CP optimized transmission: at time T1, all data is in the S-GW / UPF. The S-GW sends an indication to the base station through the MME, and the UPF sends an indication through the AMF. Alternatively, the S-GW / UPF directly indicates to the base station the tracking area where the terminal with data is located within the time period [T1, T2].

[0167] ii. UP optimized transmission: at time T1, all data is transmitted through the S-GW / UPF. The S-GW transmits the data to the base station via the MME, and the UPF transmits the data to the base station via the AMF. Alternatively, the S-GW / UPF directly transmits the data to the base station, indicating the tracking area of ​​the terminal corresponding to the data within the time interval [T1, T2].

[0168] Optionally, the indication information may also include a duration, which is based on the [T1,T2] time data of the MME / AMF notification. It can be in the form of [T1±t1, T2±t2], where t1 and t2 are preset time values ​​used to flexibly adjust the duration window.

[0169] S202, Based on the area information in the instruction information, the terminal:

[0170] When it is determined that the area is not a subset of the first area, the paging message of satellite 1 is monitored, or an RRC connection is established, such as initiating a registration process, an RRC connection establishment process, an RRC connection recovery process, or an attachment process (the same below).

[0171] When it is determined that the area is a subset of the first area, the following actions are taken: do not listen to some or all of the paging messages of satellite 1, or do not establish an RRC connection, for example, do not initiate the registration process, do not initiate the RRC connection establishment process, do not initiate the RRC connection recovery process, and do not initiate the attach process (the same below);

[0172] When it is determined that the area where the person is located overlaps with the third area, the paging message of the listening satellite 1 is executed, or an RRC connection is established;

[0173] If it is determined that the area in question does not overlap with the third area, then the system will either not listen to some or all of the paging messages of satellite 1, or will not establish an RRC connection.

[0174] Optionally, when the area information is an area on the Earth's surface, the terminal determines it based on its own location information:

[0175] If it is determined that the area is not in the first area, execute the paging message of listening satellite 1, or establish an RRC connection;

[0176] When it is determined that the area is located in the first area, execute the action of not listening to some or all of the paging messages of satellite 1, or not establishing an RRC connection;

[0177] When it is determined that the area in question belongs to the third area, execute the paging message of listening satellite 1, or establish an RRC connection;

[0178] If it is determined that the area in question does not belong to the third area, then the system will either not listen to some or all of the paging messages of satellite 1, or will not establish an RRC connection.

[0179] When the area information in the indication message is tracking area information (at least one tracking area, which can be considered as indicating a set of tracking areas), because the terminal can store one or more tracking areas, when a terminal within the tracking area covered by satellite 1 receives the indication message, if one of the tracking areas stored by the terminal is indicated to have data (one tracking area belongs to (∈) a third area), the terminal listens for paging messages from satellite 1 or establishes an RRC connection; however, if none of the stored areas are indicated to have no data (none of the stored tracking areas belong to (∈) a third area), the terminal listens for paging messages from satellite 1 or establishes an RRC connection; otherwise, if none of the stored areas are indicated to have data (none of the stored tracking areas belong to (∈) a third area), the terminal listens for paging messages from satellite 1 or establishes an RRC connection. If the terminal is in the third region, it will not listen to the paging messages of satellite 1, or will not establish an RRC connection.

[0180] Optionally, when using the Earth surface area indicator, the terminal can also determine whether it is within the issued Earth surface area based on its own location information (which may or may not include the boundary, depending on the preset settings).

[0181] Specifically, the terminal can not listen to paging messages in the following ways, which can also be called the non-listening-to-paging-message ...

[0182] a) After receiving the indication information, the terminal determines that there is no downlink data from satellite 1. The terminal will only listen for paging once within the system information modification period, or a preset finite number of times n (n is a positive integer). During other paging opportunities within the system information modification period, the terminal will not listen for paging. Correspondingly, the base station can extend the system information modification period as much as possible to allow the terminal to save power.

[0183] (b) After receiving the indication information, the terminal determines that there is no downlink data from the terminal on satellite 1 and enters a mode that does not listen for paging messages. The terminal can deactivate or suspend the access stratum (AS). The terminal can save the AS-related configuration information; or keep all running timers running, but not perform any idle mode tasks, such as measurements. These timers include a terminal location information validity period timer (if this timer expires, the terminal's location information is considered invalid or inaccurate); a satellite ephemeris information or satellite auxiliary information validity period timer (if this timer expires, the satellite auxiliary information is considered invalid or inaccurate); or not trigger the connection establishment / random access process after listening for a paging message used for data transmission; or stop all paging listening; or keep running timers running while not performing at least one of the idle mode tasks. Before or after (preset time) when satellite 1 or the serving cell of satellite 1 stops coverage / stops service, the terminal performs all idle mode tasks. Or, when the terminal has uplink data to wait for, it performs all idle mode tasks.

[0184] To further illustrate, such as Figure 5As shown, at time T1.5 within the time interval [T1, T2], the satellite covers the tracking areas TACm-1 and TACm. At this time, the satellite only buffers data 1, which needs to be sent to UE1 in TACm. Satellite 1 then sends an indication message indicating that TACm-1 has no data and TACm has data;

[0185] If the tracking area information stored by UE1 is TACm, then UE1 determines, based on the indication information from satellite 1, whether it needs to listen for paging messages or establish an RRC connection to receive downlink data.

[0186] If the tracking area information saved by UE2 is TACm-1, then UE2 determines, based on the indication information from satellite 1, that it does not need to receive downlink data, that is, it does not need to listen to paging messages, or it does not need to establish an RRC connection, and directly sets itself to the mode of not listening to paging messages.

[0187] Optionally, satellite 1 can also explicitly indicate the area information where there is no data. In this case, when the terminal makes a judgment, it needs to perform the opposite processing as described above. For example, if the area where the terminal is located is associated with the area indicated by the indication information, it will not listen or establish an RRC connection; if the area where the terminal is located is not associated with the area indicated by the indication information, it will listen or establish an RRC connection.

[0188] Optionally, the indication information can also simultaneously indicate that satellite 1 has cached downlink data from terminals located in area 1, and that satellite 1 does not have cached downlink data from terminals in area 2. In this case, the terminal can compare the first and third areas separately and, based on the logic above, determine whether it needs to listen for paging messages or establish an RRC connection.

[0189] In another possible scenario, the system flow includes:

[0190] S301, Satellite 1 (base station) sends an indication message indicating the group ID (referred to as the first group number) of the terminal corresponding to the stored / cached data.

[0191] Optionally, it can also indicate that there is cached data in part or all of the area covered or served by the base station on the current satellite 1; the indicated area is called the third area.

[0192] Optionally, it can also indicate that there is no cached data in part or all of the area covered or served by the base station on the current satellite 1, and the indicated area is called the first area.

[0193] Alternatively, it can indicate that there is data in the tracking area of ​​the current system message broadcast by the base station.

[0194] The terminal groupID is assigned to the terminal by the core network control. Specifically, the MME / AMF may configure a terminal groupID for the terminal. In preceding procedures, such as the access procedure, the terminal requests packets from the MME / AMF or instructs the terminal to support packets; the MME / AMF configures and sends the groupID to the terminal. Optionally, the MME / AMF may also send the groupID to the base station (or send it to the base station in a subsequent procedure). Specifically, the groupID can be numbered 1, 2, 3, 4…n, divided into n groups, used to distinguish terminals within the coverage / service area.

[0195] Optionally, regarding the method by which the terminal obtains the groupID number, in addition to MME / AMF indication, the base station and the terminal can also determine the groupID number based on the terminal's UE ID (and / or the total number of groupIDs based on the UE ID), or by determining the subgroup ID number of the groupID. The base station can send the total number of groupIDs to the terminal, or agree on the ID number in advance with the core network and the terminal.

[0196] The UE ID here can be either IMSI or 5G-S-TMSI. The core network can determine and configure the groupID using methods such as IMSI mod X or 5G-S-TMSI mod X. X can be any preset integer; mod is a modulo operation.

[0197] In NTN, there are several different uplink architectures, and the following situations apply to these different architectures.

[0198] a) Base station only: Optimized transmission for CP and UP, data is stored at the base station, i.e., stored on satellite 1 (all data arrives at the base station at time T1, i.e., the feeder link is disconnected at time T1). In this case, the base station can determine the tracking area corresponding to the terminal to which the data is to be sent. The MME / AMF needs to send the groupID of the terminal corresponding to the data to the base station (or send it to the base station in advance). If the groupID is determined based on the UE ID, the base station can determine it itself and does not need to send the groupID separately.

[0199] b) Base station and part or all of the MME / AMF are uploaded to satellite:

[0200] i. CP optimized transmission: all data at time T1 is sent to MME / AMF, and MME / AMF notifies the base station of the tracking area and groupID corresponding to the [T1,T2] time data (or sends it to the base station in advance);

[0201] ii.UP optimized transmission: all data at time T1 reaches the base station, but the MME / AMF knows the tracking area corresponding to these data. The MME / AMF notifies the base station of the tracking area and groupID corresponding to the data at time [T1, T2] (either sent to the base station in advance; or determined by the base station itself based on the UE ID).

[0202] c) Base station and (partial) core network CN uplink:

[0203] i. CP optimized transmission: at time T1, all data is in the S-GW / UPF. The S-GW sends an indication to the base station via the MME, and the UPF sends an indication via the AMF. Alternatively, the S-GW / UPF directly indicates to the base station the tracking area with data within the time period [T1, T2] and the groupID (or sends it to the base station in advance). If the groupID is determined based on the UE ID, the base station can determine it itself and does not need to send the groupID separately.

[0204] ii. UP optimized transmission: at time T1, all data is in the S-GW / UPF. The S-GW sends an indication to the base station via the MME, and the UPF sends an indication via the AMF. Alternatively, the S-GW / UPF directly indicates to the base station the tracking area with data within the time period [T1, T2] and the groupID (or sends it to the base station in advance). If the system is pre-configured and a scheme based on the UE ID to determine the groupID is adopted, then since the base station / terminal can determine it itself, there is no need to send the groupID separately.

[0205] Optionally, the indication information may also include the duration, which is based on the [T1,T2] time data of the MME / AMF notification. It can be in the form of [T1±t1, T2±t2], where t1 and t2 are preset time values ​​used to flexibly adjust the duration window. For example, when the adjustment value is 0, it is the actual duration.

[0206] S302, after receiving the sent instruction information, the terminal makes a judgment based on its own group number (referred to as the second group number).

[0207] When it is determined that the second group number matches the first group number, listen for the paging message of satellite 1, or establish an RRC connection with satellite 1;

[0208] If it is determined that the second group number does not match the first group number, do not listen to some or all of the paging messages of satellite 1, or do not establish an RRC connection with satellite 1;

[0209] When it is determined that the area where the user is located overlaps with the third area and the second group number matches the first group number, listen for the paging message of satellite 1, or establish an RRC connection with satellite 1.

[0210] If the area where the user is located overlaps with the third area, but the second group number does not match the first group number, then the user will not listen to some or all of the paging messages of satellite 1, or will not establish an RRC connection with satellite 1.

[0211] Optionally, when the area information is an area on the Earth's surface, the terminal determines it based on its own location information:

[0212] When it is determined that the second group number matches the first group number, listen for the paging message of satellite 1, or establish an RRC connection with satellite 1;

[0213] If it is determined that the second group number does not match the first group number, do not listen to some or all of the paging messages of satellite 1, or do not establish an RRC connection with satellite 1;

[0214] When it is determined that the area where you are located belongs to the third area and the second group number matches the first group number, listen for the paging message of satellite 1, or establish an RRC connection with satellite 1;

[0215] If the area where the user is located is determined to belong to the third area, but the second group number does not match the first group number, then the user will not listen to some or all of the paging messages of satellite 1, or will not establish an RRC connection with satellite 1.

[0216] The determination of regional information is the same as that described in S202 above.

[0217] To further illustrate, such as Figure 6 As shown, at time T1.5 within the time interval [T1, T2], the satellite covers the tracking areas TACm-1 and TACm. At this time, the satellite only buffers data 1, which is to be sent to UE1 in TACm. Satellite 1 sends an indication message indicating that there is no data in TACm-1 and that there is data in TACm, and in the indication message, it sends the groupID of the terminal corresponding to the data: groupID1;

[0218] The tracking area information saved by UE1 is TACm, and the groupID saved by UE1 is groupID1. According to the indication information sent by satellite 1, the tracking area and groupID are matched at the same time. Therefore, UE1 determines that it needs to listen for paging messages or establish an RRC connection to receive downlink data.

[0219] The tracking area information saved by UE2 is TACm, and the groupID saved by UE1 is groupID2. According to the indication information sent by satellite 1, the tracking area and groupID do not match at the same time. Therefore, UE2 determines that it needs to listen to paging messages but does not need to receive downlink data, or does not establish an RRC connection, and directly sets itself to the mode of not listening to paging messages.

[0220] Optionally, satellite 1 can also explicitly indicate the groupID and / or area information where there is no data. In this case, when the terminal makes a judgment, it needs to perform the opposite processing as described above. That is, if the terminal's groupID and the area it is located in match the indication information, it means there is no data, and it can choose not to listen or establish an RRC connection; if either does not match, it means there is data, and it needs to listen or establish an RRC connection.

[0221] Alternatively, in addition to indicating the group, the indication information can also simultaneously indicate that satellite 1 has cached downlink data from terminals located in area 1 and that satellite 1 does not have cached downlink data from terminals in area 2. In this case, the terminal can compare area 1 and area 2 separately and, based on the logic above, determine whether it needs to listen for paging messages or whether it needs to establish an RRC connection.

[0222] Figure 7 This is a schematic block diagram of a communication device provided in an embodiment of this application. Figure 7 As shown, the communication device 700 may include a processing unit 710 and a communication unit 720. The communication unit 720 can implement corresponding communication functions, which can be internal communication within the communication device 700 or communication between the communication device 700 and other devices; the processing unit 710 can implement corresponding processing functions. The communication unit 720 may also be referred to as a communication interface or transceiver unit. Optionally, the communication device 700 may further include a storage unit, which can be used to store instructions and / or data. The processing unit 710 can read the instructions and / or data from the storage unit to enable the device to implement the aforementioned method embodiments.

[0223] In one possible design, the communication device 700 can be a terminal device in the communication method described above, or it can be a module or chip applied to a terminal device. The communication device 700 can be used to execute the steps or processes performed by the terminal device in the above method embodiments. Optionally, the communication device 700 can be a network device in the communication method described above, or it can be a module or chip applied to a network device. The communication device 700 can be used to execute the steps or processes performed by the network device in the above communication method embodiments.

[0224] For details regarding the steps or processes executed by each unit in the communication device 700, please refer to the embodiments of the method described above; they will not be elaborated here.

[0225] It should be understood that the "unit" in the communication device 700 can be implemented in hardware, software, or by hardware executing corresponding software. For example, the "unit" can refer to an application-specific integrated circuit (ASIC), electronic circuitry, a processor (e.g., a shared processor, a proprietary processor, or a group processor) and memory for executing one or more software or firmware programs, combined logic circuitry, and / or other suitable components supporting the described functions. As another example, the communication unit 720 can be replaced by a transceiver circuit (e.g., it may include receiving and transmitting circuitry), and the processing unit 710 can be replaced by a processor or processing circuitry.

[0226] Figure 8 A schematic block diagram of another communication device 800 provided in an embodiment of this application is shown. This communication device 800 may be a terminal device or a network device, or it may be a chip, chip system, or processor that supports the terminal device or network device in implementing the above methods. This device can be used to implement the methods described in the above method embodiments; for details, please refer to the descriptions in the above method embodiments.

[0227] The communication device 800 may include one or more processors 810, which may also be referred to as processing units, and can implement certain control functions. The processor 810 may be a general-purpose processor or a dedicated processor, such as a baseband processor or a central processing unit. The baseband processor can be used to process communication protocols and communication data, while the central processing unit can be used to control the communication device (e.g., base station, baseband chip, user chip, DU or CU, etc.), execute software programs, and process data from the software programs.

[0228] In an alternative design, the processor 810 may also store instructions and / or data that can be executed by the processor 810 to cause the communication device 800 to perform the methods described in the above method embodiments. Optionally, the processing unit 710 in the communication device 700 may be the processor 810.

[0229] In another alternative design, the communication device 800 may include a communication interface 820 for implementing receiving and transmitting functions. For example, the communication interface 820 may be a transceiver circuit, interface, interface circuit, or transceiver. The transceiver circuit, interface, interface circuit, or transceiver for implementing receiving and transmitting functions may be separate or integrated. The aforementioned transceiver circuit, interface, interface circuit, or transceiver may be used for reading and writing code / data, or it may be used for transmitting or relaying signals. Optionally, the communication unit 720 in the communication device 700 may be the communication interface 820.

[0230] Optionally, the communication device 800 may include one or more memories 830, which may store instructions that can be executed on the processor 810, causing the communication device 800 to perform the methods described in the above method embodiments. Optionally, the memories 830 may also store data. Optionally, the processor 810 may also store instructions and / or data. The processor 810 and the memories 830 may be provided separately or integrated together.

[0231] Those skilled in the art will understand that, for ease of explanation, Figure 8 Only one memory and processor are shown. In actual communication devices, multiple processors and memories may exist. Memory can also be called storage medium or storage device, etc., and the embodiments of this application do not limit this.

[0232] For example, a processor may include a baseband processor and a central processing unit (CPU). The baseband processor is mainly used to process communication protocols and communication data, while the CPU is mainly used to control the entire terminal device, execute software programs, and process the data of the software programs. Figure 8 The processor integrates the functions of a baseband processor and a central processing unit (CPU). Those skilled in the art will understand that the baseband processor and CPU can also be independent processors interconnected via technologies such as buses. It will also be understood that a terminal device can include multiple baseband processors to adapt to different network standards, and multiple CPUs to enhance its processing capabilities. The various components of the terminal device can be connected via various buses. The baseband processor can also be described as a baseband processing circuit or a baseband processing chip. Similarly, the CPU can be described as a central processing circuit or a central processing chip. The function of processing communication protocols and communication data can be built into the processor or stored as software programs in a storage unit, with the processor executing the software programs to implement the baseband processing function.

[0233] It should be understood that, in one possible design, the steps in the method embodiments provided in this application can be implemented by integrated logic circuits in the processor's hardware or by instructions in software form. The steps of the methods disclosed in the embodiments of this application can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules in the processor. The software modules can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory, and the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method. To avoid repetition, detailed descriptions are not provided here.

[0234] It should be noted that the processor in the embodiments of this application can be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method embodiments can be completed by the integrated logic circuitry in the processor's hardware or by instructions in software form. The processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly embodied as being executed by a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules can be located in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory, and the processor reads the information in the memory and, in conjunction with its hardware, completes the steps of the above methods.

[0235] It is understood that the memory in the embodiments of this application can be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory can be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous linked dynamic random access memory (SLDRAM), and direct rambus RAM (DR RAM). It should be noted that the memory used in the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0236] This application also provides a computer program product, which includes computer program code. When the computer program code is run on a computer, it causes the computer to execute the various steps or processes executed by the terminal device or network device in any of the above method embodiments.

[0237] This application also provides a computer-readable storage medium storing program code that, when run on a computer, causes the computer to execute the various steps or processes performed by the terminal device or network device in any of the above method embodiments.

[0238] This application also provides a communication device, including a processor and an interface for sending and / or receiving signals, causing the processor to execute the various steps or processes performed by the terminal device or network device in any of the above method embodiments.

[0239] This application also provides a communication system, which includes a terminal device and a network device.

[0240] The above-described device and method embodiments are completely corresponding, with corresponding modules or units performing corresponding steps. For example, a communication unit or communication interface performs the receiving or sending steps in the method embodiment, while other steps besides sending and receiving can be performed by a processing unit or processor.

[0241] In the embodiments of this application, the terms and English abbreviations are exemplary examples given for ease of description and should not be construed as limiting the application in any way. This application does not preclude the possibility of defining other terms that can achieve the same or similar functions in existing or future agreements.

[0242] As used in this specification, the terms "component," "module," "system," etc., are used to refer to computer-related entities, hardware, firmware, combinations of hardware and software, software, or software in execution. For example, a component can be, but is not limited to, a process running on a processor, a processor, an object, an executable file, an execution thread, a program, and / or a computer. As illustrated, applications running on computing devices and computing devices can both be components. One or more components may reside in a process and / or an execution thread, and components may be located on a single computer and / or distributed among two or more computers. Furthermore, these components can be executed from various computer-readable storage media on which various data structures are stored. Components can communicate, for example, via local and / or remote processes based on signals having one or more data packets (e.g., data from two components interacting with another component between a local system, a distributed system, and / or a network, such as the Internet interacting with other systems via signals).

[0243] Those skilled in the art will recognize that the various illustrative logical blocks and steps described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this application.

[0244] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be based on the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0245] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0246] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0247] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0248] In the above embodiments, the functions of each functional unit can be implemented entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer instructions (programs). When the computer program instructions (programs) are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state disks, SSDs), etc.

[0249] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0250] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A communication method applied to NTN communication, characterized in that, The method includes, Receive a first message, the first message containing at least one of the following: Indicates that the first network device does not cache downlink data from terminals located in the first area; or, Instruct the first network device to cache downlink data from terminals located in the third area; or, Indicates the first group number of the terminal corresponding to the downlink data cached by the first network device; The first network device is deployed on a satellite; Based on the first message, either not to listen for some or all of the paging messages from the first network device, or not to establish the first connection; or... Based on the first message, listen for paging messages from the first network device, or establish a first connection, or restore the first connection.

2. The method according to claim 1, characterized in that, Based on the first message, one of the following actions may be performed: When it is determined that the second region belongs to a subset of the first region, the following steps are taken: either not to listen to some or all of the paging messages of the first network device, or not to establish the first connection. When it is determined that the second region is not a subset of the first region, the process of listening to the paging message of the first network device is executed, or the first connection is established, or the first connection is restored. When it is determined that the second region overlaps with the third region, the process of listening to the paging message of the first network device is executed, or the first connection is established, or the first connection is restored. When it is determined that the second group number matches the first group number, the process of listening to the paging message of the first network device is executed, or the first connection is established, or the first connection is restored. If it is determined that the second group number does not match the first group number, then the following steps are taken: either not to listen to some or all of the paging messages of the first network device, or not to establish the first connection. When it is determined that the second region overlaps with the third region and the second group number matches the first group number, the process of listening to the paging message of the first network device is executed, or the first connection is established, or the first connection is restored. If it is determined that the second region overlaps with the third region, but the second group number does not match the first group number, then the following steps are taken: either not to listen to some or all of the paging messages of the first network device, or not to establish the first connection. If it is determined that the second region and the third region do not overlap, then the following steps are taken: either not to listen to some or all of the paging messages of the first network device, or not to establish the first connection.

3. The method according to claim 2, characterized in that, The first region and the third region include: The first network device covers or serves at least one tracking area, or a region of the Earth's surface, wherein the region of the Earth's surface is indicated by the region information included in the first message; The second region includes: The tracking area in which it is located, or a set of multiple tracking areas including the tracking area, or at least one of the locations in which it is located.

4. The method according to claim 3, characterized in that, The first message includes the following area information: Use latitude and longitude to indicate the location of the center point, and add the radius distance to determine a region; A pre-agreed area; Or a geometric region defined by multiple points; According to a preset setting, the area information may or may not include boundaries.

5. The method according to claim 2, characterized in that, The second group number is determined based on the received second message, or based on the terminal identifier (UE ID).

6. The method according to claim 5, characterized in that, Before receiving the first message, Send a third message that requests a packet or indicates support for a packet; Receive the second message, which includes the second group number.

7. The method according to claim 1, characterized in that, The first message also includes a duration, the start time of which is based on a first moment and a first threshold, and the end time of which is based on a second moment and a second threshold, wherein the first moment is the moment when the first network device disconnects from the ground station link, and the second moment is the moment when the first network device restores the ground station link; the first threshold and the second threshold are preset time values.

8. The method according to any one of claims 1-7, characterized in that, The statement that the paging messages of the first network device are not monitored (either partially or entirely) includes at least one of the following: Do not listen to paging messages used for data transmission from the first network device; Upon receiving a paging message for data transmission from the first network device, a connection establishment is not triggered. Listen for paging only once or a finite number of n times within the system information modification cycle; Deactivate or suspend the access stratum (AS).

9. The method according to claim 1, characterized in that, The establishment of the first connection further includes initiating the process of establishing the first connection; the restoration of the first connection further includes initiating the process of restoring the first connection.

10. The method according to claim 1, characterized in that, The first connection includes a radio resource control (RRC) connection.

11. A communication method applied to NTN communication, characterized in that, The method includes, Send a first message, the first message containing at least one of the following: This indicates that no downlink data from terminals located in the first region is cached; or, Instruct to cache downlink data from terminals located in the third region; or, Indicates the first group number of the terminal corresponding to the cached downlink data; Based on the first message, the terminal is instructed not to listen to some or all paging messages, or not to establish the first connection; or, Based on the first message, the terminal is instructed to listen for paging messages, establish a first connection, or restore the first connection.

12. The method according to claim 11, characterized in that, Based on the first message, the terminal is instructed to perform one of the following actions: When the second region is a subset of the first region, it indicates that some or all paging messages should not be listened to, or that the first connection should not be established. When the second region is not a subset of the first region, the listener is instructed to either listen to the paging message, establish a first connection, or restore the first connection. When the second region overlaps with the third region, the system instructs the monitoring paging message to either establish a first connection or restore the first connection. When the second group number matches the first group number, it instructs the monitoring of the paging message of the first network device to either establish a first connection or restore the first connection. When the second group number does not match the first group number, it indicates that some or all paging messages will not be listened to, or the first connection will not be established. When the second region overlaps with the third region and the second group number matches the first group number, the monitoring paging message is indicated, or the first connection is established, or the first connection is restored. If the second region overlaps with the third region, but the second group number does not match the first group number, it indicates that some or all paging messages will not be listened to, or the first connection will not be established. When the second region does not overlap with the third region, it indicates that some or all paging messages should not be listened to, or that the first connection should not be established.

13. The method according to claim 12, characterized in that, The first region includes: At least one tracking area or region of the Earth's surface that is covered or served, wherein the region of the Earth's surface is indicated by the region information included in the first message; The second region includes: The tracking area where the terminal is located, or a set of multiple tracking areas including the tracking area, or at least one of the locations where the terminal is located.

14. The method according to claim 13, characterized in that, The first message includes the following area information: Use latitude and longitude to indicate the location of the center point, and add the radius distance to determine a region; A pre-agreed area; Or a geometric region defined by multiple points; According to a preset setting, the area information may or may not include boundaries.

15. The method according to claim 12, characterized in that, The second group number is indicated based on the second message sent.

16. The method according to claim 15, characterized in that, Before sending the first message, Receive a third message, the third message being used to request grouping for the terminal, or to instruct the terminal to support grouping; Send a second message, which includes a second group number.

17. The method according to claim 11, characterized in that, The first message also includes a duration, the start time of which is based on a first moment and a first threshold, and the end time of which is based on a second moment and a second threshold, wherein the first moment is the moment when the ground station link is disconnected, and the second moment is the moment when the ground station link is restored; the first threshold and the second threshold are preset time values.

18. The method according to any one of claims 11-17, characterized in that, The statement that "not listening to some or all paging messages, or not establishing a first connection" includes at least one of the following: Do not listen to paging messages used for data transmission from the first network device; Upon receiving a paging message for data transmission from the first network device, a connection establishment is not triggered. Listen for paging only once or a finite number of n times within the system information modification cycle; Deactivate or pause the AS layer.

19. The method according to claim 11, characterized in that, The establishment of the first connection further includes initiating the process of establishing the first connection; the restoration of the first connection further includes initiating the process of restoring the first connection.

20. The method according to claim 11, characterized in that, The first connection includes a radio resource control (RRC) connection.

21. An electronic device, characterized in that, Includes units or modules for performing the method as described in any one of claims 1 to 10, 11 to 20.

22. A chip, characterized in that, The chip includes a processor connected to a memory for storing computer programs, and the processor is configured to execute the computer programs stored in the memory to cause the chip to perform the communication method as described in any one of claims 1 to 10, 11 to 20.

23. An electronic device, characterized in that, include: A processor coupled to a memory for storing programs or instructions that, when executed by the processor, cause the electronic device to perform the method as described in any one of claims 1 to 10, 11 to 20.

24. A computer-readable storage medium having a computer program or instructions stored thereon, characterized in that, When the computer program or instructions are executed, they cause the computer to perform the method as described in any one of claims 1 to 10, 11 to 20.

25. A computer program product, said computer program product comprising computer program code, characterized in that, When the computer program code is run on a computer, it causes the computer to implement the method of any one of claims 1 to 10, 11 to 20.

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