Communication method and apparatus

Abstract

A communication method and apparatus, applicable to an NTN, such as a satellite communication system. The method comprises: a core network device sends a NAS message to a terminal device, wherein the NAS message comprises a first satellite list, and the first satellite list is associated with a first timer; an access network device sends a system message, wherein the system message comprises a second satellite list, and each satellite in the second satellite list is respectively associated with a service start time; when the terminal device is in an idle state, the terminal device does not perform an AS operation before a first time. The first time is the minimum value among an expiration time of the first timer and a second time. The second time is the minimum value among the start service times associated with the second satellite list, or the second time is the start service time associated with one satellite in the second satellite list. By means of the method, the terminal device may not perform an AS operation before the first timer expires, thereby contributing to power saving of the terminal device.

Description

Communication methods and devices

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202510379996.X, filed on March 27, 2025, entitled "Communication Method and Apparatus", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of communication technology, and in particular to a communication method and apparatus. Background Technology

[0004] Non-terrestrial networks (NTNs) (such as satellite communication systems) have advantages such as wide coverage and long communication distance, and have been widely used in various communication fields.

[0005] The satellite will configure at least one satellite for subsequent non-continuous coverage for the UE via system messages. The UE can also perform satellite detection based on at least one satellite indicated by the system message to achieve continuous coverage as much as possible and reduce service interruptions.

[0006] Store-and-forward (S&F) technology in NTN is primarily used in scenarios where a satellite cannot simultaneously connect to both the terminal equipment and the terrestrial network; that is, the service link and the feeder link cannot be available at the same time. Store-and-forward means that when the satellite and terminal are connected (i.e., the service link is available), the satellite stores the user's data; when the satellite and the terrestrial network are connected (i.e., the feeder link is available), the user data is forwarded to the terrestrial network. Therefore, in NTN, the core network can configure the user equipment (UE) to retry the NAS procedure using at least one satellite via non-access stratum (NAS) messages. The UE can perform satellite detection based on the at least one satellite configured in the NAS message to determine whether to access the currently covered satellite for data transmission.

[0007] While waiting for satellites to be configured in the NAS, the UE usually performs operations such as cell search, which consumes a lot of power. Summary of the Invention

[0008] This application provides a communication method and apparatus that can save energy consumption of terminal devices during the access process.

[0009] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0010] Firstly, a communication method is provided, which is applied to a communication device on the terminal side. For example, the method can be applied to a terminal device or a component / part within the terminal device. Unless otherwise specified, the communication device can be a terminal device; or the communication device can be a communication module and / or computing module applied to the terminal device; or the communication device can be a circuit or chip (such as a modem chip, also known as a baseband chip, or a system-on-chip (SoC) chip containing a modem core, or a system-in-package (SIP) chip) applied to the terminal device responsible for communication and / or computing functions; or the communication device can be a circuit or chip (such as a central processing unit (CPU), an application-specific integrated circuit (ASIC), or a field-programmable gate array (FPGA)) applied to the terminal device responsible for communication and / or computing functions; or the communication device can be a logic node, logic module, or software capable of implementing all or part of the functions of the terminal device. For ease of description, the following example uses the method provided in the first aspect applied to a terminal device.

[0011] The method includes: receiving NAS messages and system messages; and, when the terminal device is in an idle state, not performing access stratum (AS) operations before a first time. The NAS message includes a first satellite list associated with a first timer, which indicates the waiting time for retrying the NAS process. The system message includes a second satellite list, where each satellite in the second satellite list is associated with a service start time. The first time is the minimum of the end time of the first timer and the second time. The second time is either the minimum of the service start times associated with the second satellite list, or the service start time associated with a single satellite in the second satellite list.

[0012] In this method, the first satellite list can be viewed as at least one satellite configured by the terminal device via NAS messages to retry the NAS process. The second satellite list can be viewed as at least one satellite configured by the terminal device via system messages for subsequent non-continuous coverage. If the terminal device is configured with both the first and second satellite lists, when the terminal device is in an idle state, it does not perform AS operations (such as cell search, paging detection, etc.) before a first time. The first time is either the end time of the first timer or the second time (i.e., a start service time associated with the second satellite list, such as a minimum start service time). When the first time is the end time of the first timer, the terminal device does not perform cell search or paging detection before the end time of the first timer. Compared to continuously performing operations such as cell search while waiting for satellites in the first satellite list (e.g., before the end time of the first timer), this reduces the power consumption of the terminal device, making it particularly suitable for Internet of Things (IoT) terminal devices. When the first time is the second time, while waiting for satellites in the first satellite list, satellite detection can be performed based on the second satellite list configured by the system message. If a satellite is detected, the satellite access process can be executed. It is not necessary to wait until the satellites in the first satellite list are in the process (such as before the end time of the first timer) before the satellite access is executed. Therefore, the satellite can be accessed as early as possible, reducing the latency of accessing the network.

[0013] In one design, the satellite identifier portions of the first satellite list and the second satellite list may be the same or completely different. This design helps improve coverage and system capacity. For example, the second satellite list can contain more satellites than the first satellite list, thereby achieving wide-area coverage and increasing system capacity. Optionally, it can be predefined or agreed that the satellite ID portions of the first satellite list and the second satellite list may be the same or completely different, eliminating the need for the terminal device to determine whether the first satellite list and the second list are the same, thus reducing the complexity of the terminal device.

[0014] In one design, the NAS message includes a first timer. This design allows for flexible configuration of the first timer via the NAS message, helping the network side dynamically adjust the waiting time for each terminal device to retry the NAS process, reducing network congestion and avoiding increased signaling interaction caused by terminal devices frequently attempting the NAS process. For example, if current network resources are limited, a longer first timer can be configured to prevent terminal devices from failing to access the network due to insufficient resources and subsequently retrying the NAS process.

[0015] In one design, the end time of the first timer is later than the second time. The method further includes: after the second time arrives, if the first satellite's operating mode is normal, executing the access procedure for the first satellite; or, after the second time arrives, if the first satellite's operating mode is store-and-forward mode, not executing the access procedure for the first satellite. If the satellite's operating mode is normal, then the satellite can obtain the context of the terminal device; if the satellite's operating mode is store-and-forward mode, then the satellite may not be able to obtain the context of the terminal device. In this design, when the first satellite's operating mode is normal, the terminal device is highly likely to successfully access the first satellite; therefore, executing the access procedure for the first satellite can reduce the latency of the terminal device accessing the network. When the first satellite's operating mode is store-and-forward mode, the terminal device is highly likely to fail to access the network; therefore, not executing the access procedure for the first satellite reduces unnecessary signaling interactions.

[0016] In one design, if the process of accessing the first satellite is not executed, no AS operation is performed before a third time. The third time is the minimum of the end time of the first timer and the fourth time. The fourth time is the minimum of the start service times of satellites in the second satellite list that are greater than the second time. In this design, if the terminal device detects the first satellite but does not execute the process of accessing the first satellite, then AS operation can be omitted before the next start service time in the second satellite list, in order to minimize the power consumption of the terminal device.

[0017] In one design, the second time is the minimum service start time associated with satellites operating in normal mode in the second satellite list. Considering that satellites in store-and-forward mode may fail to acquire the terminal device's context, leading to satellite access failure, this design constrains the second time to ensure that the terminal device detects satellites operating in normal mode as much as possible, and does not detect satellites operating in store-and-forward mode. This minimizes the terminal device's power consumption and improves the success rate of satellite access.

[0018] In one design, the end time of the first timer is later than the second time. The method further includes executing the satellite access procedure after the second time has elapsed. In this design, the end time of the first timer is later than the second time, and the first time is the same as the second time. Before the end time of the first timer, a satellite may be detected. Therefore, the satellite access procedure is executed after the first time (i.e., the second time) has elapsed, without waiting for the end time of the first timer, in order to minimize the latency of network access.

[0019] In one design, the system message also includes information about the operating modes of satellites in the second satellite list. This design indicates the operating modes of satellites in the second satellite list via the system message, eliminating the need for additional signaling and thus saving signaling overhead.

[0020] Secondly, a communication method is provided, which can be applied to a communication device on the terminal side. For details regarding the communication device on the terminal side, please refer to the relevant description in the first aspect above; it will not be repeated here. For ease of description, the following example uses the method provided in the second aspect applied to a terminal device.

[0021] The method includes: receiving NAS messages and system messages, and, when the terminal device is in an idle state, not performing AS operations before a first time. The NAS message includes a first satellite list associated with a first timer, which indicates the waiting time for retrying the NAS process. The system message includes a second satellite list, where each satellite in the second satellite list is associated with a service start time, and the second satellite list contains the first satellite list. The first time is a second time, which is either the minimum of the service start times associated with the second satellite list, or the service start time associated with a satellite in the second satellite list.

[0022] In this method, if the terminal device is configured with a first satellite list and a second satellite list, and the second satellite list includes the first satellite list, the terminal device does not perform AS operations (such as cell search, paging detection, etc.) before the first (or second) time when it is in an idle state. Since the second satellite list includes the first satellite list, even if the terminal device detects satellites according to the second time, it will not miss any satellites in the first satellite list. Therefore, the terminal device does not need to perform AS operations before the first time. Compared to continuously performing operations such as cell search while waiting for satellites in the first satellite list (such as before the end of the first timer), this method minimizes the power consumption of the terminal device, making it particularly suitable for IoT terminal devices.

[0023] In one design, the second time is the minimum service start time associated with satellites operating in normal mode in the second satellite list. This design considers that satellites in store-and-forward mode may fail to acquire the terminal device's context, leading to satellite access failure. By constraining the second time, the terminal device can prioritize detecting satellites operating in normal mode and avoid detecting those operating in store-and-forward mode, thereby minimizing the terminal device's power consumption and improving the success rate of satellite access.

[0024] In one design, the method further includes executing a satellite access procedure after reaching a fifth time. The fifth time is the minimum of the second and sixth times, where the sixth time is the minimum start-of-service time of the fourth satellite in the second satellite list, and the fourth satellite is a satellite in the first satellite list. In this design, if the terminal device knows the operating modes of each satellite in the second satellite list, the terminal device executes the satellite access procedure after the fifth time to try to access satellites operating in normal mode, thereby improving the success rate of satellite access for the terminal device.

[0025] In one design, the system message also includes information about the operating modes of satellites in the second satellite list. This design indicates the operating modes of satellites in the second satellite list via the system message, eliminating the need for additional signaling and thus saving signaling overhead.

[0026] Thirdly, a communication method is provided, which can be applied to a communication device on the terminal side. For details regarding the communication device on the terminal side, please refer to the relevant description in the first aspect above; it will not be repeated here. For ease of description, the following example uses the method provided in the third aspect applied to a terminal device.

[0027] The method includes: receiving a NAS message and, based on the NAS message, executing a procedure to access a first satellite. The NAS message includes a first timer and / or a list of first satellites. The first timer is used to indicate the waiting time for retrying the NAS procedure, and the first timer is associated with a first satellite, which is the first available satellite capable of obtaining the context of the terminal device. The list of first satellites includes a first satellite, which is the first satellite among the satellites after the terminal device leaves the current satellite capable of obtaining the context of the terminal device.

[0028] In this method, since the first satellite associated with the first timer can obtain the context of the terminal device, there will be no satellite in normal mode while waiting for the NAS satellite. Even if a satellite in normal mode appears, it is configured to the terminal device by the NAS message. In this case, for the terminal device in the idle state, no AS operation is performed before the end of the first timer to reduce the power consumption of the terminal device.

[0029] Fourthly, a communication method is provided, which can be applied to a communication device on the terminal side. For details regarding the communication device on the terminal side, please refer to the relevant description in the first aspect above; it will not be repeated here. For ease of description, the following example uses the method provided in the fourth aspect applied to a terminal device.

[0030] The method includes: receiving a system message, and, based on the system message, executing a procedure to access satellites in the second satellite list. The system message includes the second satellite list. Wherein, the satellite sending the system message is operating in normal mode, and the second satellite list includes only satellites operating in normal mode. Alternatively, the satellite sending the system message is operating in store-and-forward mode, and the second satellite list includes satellites operating in normal mode and / or satellites operating in store-and-forward mode.

[0031] In this method, if the satellite sending the system message is operating in normal mode, the second satellite list only includes satellites operating in normal mode. This ensures that the terminal device can parse information from satellites in the second satellite list, allowing the terminal device to still normally reside on satellites in the second satellite list. Furthermore, including only satellites operating in normal mode in the second satellite list reduces the amount of information included in the system message, lowering air interface resource overhead. If the satellite sending the system message is operating in store-and-forward mode, the second satellite list includes satellites operating in normal mode and / or satellites operating in store-and-forward mode, enabling the terminal device to obtain more satellite information and thus supporting rapid access for the terminal device.

[0032] Fifthly, a communication method is provided, which is applied to a communication device on the core network side. For example, the method can be applied to core network equipment, or to a component within the core network equipment. Unless otherwise specified, the communication device can be a core network device; or it can be a circuit or chip (such as a modem chip (also known as a baseband chip), or a SoC chip or SIP chip containing a modem core), chip system, or processor applied to the core network equipment responsible for communication functions; or it can be a circuit or chip (such as a CPU, GPU, NPU, AI processor, ASIC, or FPGA) applied to the core network equipment responsible for communication and / or computing functions; or it can be a logical node, logical module, or software capable of implementing all or part of the core network equipment functions. In one example, the core network equipment is a mobility management entity (MME) or an access and mobility management function (AMF). For ease of description, the following example uses the method provided in the fifth aspect applied to a core network device.

[0033] The method includes: sending a NAS message, the NAS message including a first timer and / or a first satellite list. The first timer is used to indicate the waiting time for retrying the NAS process, and the first timer is associated with a first satellite, which is the first available satellite capable of obtaining the context of the terminal device. The first satellite list includes a first satellite, which is the first satellite among the satellites after the terminal device leaves the current satellite capable of obtaining the context of the terminal device.

[0034] For the beneficial effects of the fifth aspect, please refer to the beneficial effects of the third aspect mentioned above, which will not be repeated here.

[0035] Sixthly, a communication method is provided, which is applied to a communication device on the network side, such as a satellite or a component within a satellite. Unless otherwise specified, the communication device can be a satellite; or it can be a communication module and / or computing module applied to a satellite; or it can be a circuit or chip (such as a modem chip (also known as a baseband chip), or a SoC chip or SIP chip containing a modem core), chip system, or processor applied to a satellite responsible for communication functions; or it can be a circuit or chip (such as a CPU, GPU, NPU, AI processor, ASIC, or FPGA) applied to a satellite responsible for communication and / or computing functions; or it can be a logical node, logical module, or software capable of implementing all or part of the satellite's functions. For ease of description, the method provided in the sixth aspect is used as an example of its application to a satellite.

[0036] The method includes: transmitting a system message, the system message including a second satellite list. Wherein, the satellite transmitting the system message operates in normal mode, and the second satellite list includes only satellites operating in normal mode. Alternatively, the satellite transmitting the system message operates in store-and-forward mode, and the second satellite list includes satellites operating in normal mode and / or satellites operating in store-and-forward mode.

[0037] For the beneficial effects of the sixth aspect, please refer to the beneficial effects of the fourth aspect mentioned above, which will not be repeated here.

[0038] In a seventh aspect, a communication method is provided, which is applied to a communication device on the network management side. For example, the method can be applied to operations, administration, and maintenance (OAM) equipment, or to OAM components (such as modules, SoC chips, or SIP chips). Unless otherwise specified, the communication device can be an OAM device; or it can be a component applied to an OAM device; or it can be a logical node, logical module, or software capable of implementing all or part of the functions of the OAM device. For ease of description, the method provided in the seventh aspect is used as an example of its application to an OAM device.

[0039] The method includes: sending first information, which indicates the correspondence between ephemeris information and satellite identifiers.

[0040] In this method, the OAM device can configure first information for both core network devices and satellites. Even if the satellite ID is not globally unique, it will not cause the same satellite ID to have different meanings in NAS messages and system messages, thus preventing terminal devices from executing the process of accessing the wrong satellite.

[0041] In one design, the first information is also used to indicate the correspondence between geographic location information and ephemeris information. Alternatively, the first information is also used to indicate the correspondence between geographic location information and satellite identifiers. Or, the first information is also used to indicate the correspondence between geographic location information, ephemeris information, and satellite identifiers.

[0042] Eighthly, a communication method is provided, which is applied to a communication device on the network side. For example, the method can be applied to a satellite, or to a component (such as a module, SoC chip, or SIP chip) within a satellite; or, for example, to an MME, or to a component (such as a module, SoC chip, or SIP chip) within an MME. Unless otherwise specified, the communication device can be a satellite; or the communication device can be a component applied to a satellite; or the communication device can be a logical node, logical module, or software capable of implementing all or part of the satellite's functions. Alternatively, the communication device can be an MME; or the communication device can be a component applied to an MME; or the communication device can be a logical node, logical module, or software capable of implementing all or part of the MME's functions.

[0043] The method includes: receiving first information, which indicates the correspondence between ephemeris information and satellite identifiers.

[0044] In one design, the first information is also used to indicate the correspondence between geographic location information and ephemeris information. Alternatively, the first information is also used to indicate the correspondence between geographic location information and satellite identifiers. Or, the first information is also used to indicate the correspondence between geographic location information, ephemeris information, and satellite identifiers.

[0045] Ninthly, a communication device is provided for performing the method described in any of the first to eighth aspects and any design thereof. The beneficial effects can be found in the relevant descriptions of the first to eighth aspects, which will not be repeated here.

[0046] In one possible design, the communication device includes corresponding means, modules, or units for performing the methods of any of the first to eighth aspects. These modules, units, or means can be implemented in software, hardware, or a combination of both. For example, the communication device includes a processing unit (sometimes also called a processing module or processor) and / or input / output interfaces. Input / output interfaces include input interfaces and / or output interfaces, which can be interface circuits, output circuits, input circuits, pins, or related circuits, etc. Optionally, the communication device also includes a transceiver unit (sometimes also called a transceiver module or transceiver). The transceiver unit is capable of both transmitting and receiving functions. When the transceiver module implements the transmitting function, it can be called a transmitting unit (sometimes also called a transmitting module); when the transceiver module implements the receiving function, it can be called a receiving unit (sometimes also called a receiving module). The transmitting unit and the receiving unit can be the same functional module; or, the transmitting unit and the receiving unit can be different functional modules. In one example, the processing unit includes (or is) a baseband device, and the transceiver unit includes (or is) a radio frequency device. These input / output interfaces and units (modules) can perform the corresponding functions in the method examples of any of the first to eighth aspects mentioned above. For details, please refer to the detailed description in the method examples, which will not be repeated here.

[0047] For example, when the communication device is used to implement the corresponding function in the method example of the first aspect, the transceiver unit is used to receive non-NAS messages and system messages, and when the terminal device is in an idle state, no AS operation is performed before a first time. The processing unit is used to determine that the terminal device is in an idle state. The NAS message includes a first satellite list associated with a first timer, which indicates a waiting time for retrying the NAS procedure. The system message includes a second satellite list, where each satellite in the second satellite list is associated with a start service time. The first time is the minimum of the end time of the first timer and the second time. The second time is either the minimum of the start service times associated with the second satellite list, or the start service time associated with one satellite in the second satellite list.

[0048] A tenth aspect provides a communication device including a communication interface and one or more processors. Optionally, the communication interface is an interface circuit. The communication interface is used to implement communication functions within the communication device and / or for the communication device to communicate with other devices or components. In possible designs, one or more processors communicate with other devices or components through the communication interface.

[0049] One or more processors are coupled to a memory for storing part or all of a computer program (also referred to as code or instructions) necessary for implementing any of the first to eighth aspects and the functions involved in any of their designs. The one or more processors can execute the computer program (or code or instructions), which, when executed, causes the communication device to implement the methods in any of the first to eighth aspects and any of their designs.

[0050] This application does not limit the specific type of processor. For example, the processor can be a baseband device, a CPU, or other specific integrated circuits. As another example, the processor can be other general-purpose processors, DSPs, ASICs, FPGAs, or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0051] In one possible design, the memory is located outside the communication device, or inside the communication device, or the processor and memory are integrated together.

[0052] Eleventhly, a chip system is provided, comprising a processor and potentially a communication interface for implementing any of the first to eighth aspects and methods thereof. Optionally, the chip system further comprises a memory. The memory stores computer programs (also referred to as code or instructions). The processor retrieves and executes the computer programs from the memory, causing a device equipped with the chip system to perform any of the first to eighth aspects and methods thereof. The chip system may be composed of chips or may include chips and other discrete devices.

[0053] In a twelfth aspect, a communication device is provided, comprising an input / output interface and logic circuitry. The input / output interface is used for inputting and / or outputting information. The input / output interface may be an interface circuit, an output circuit, an input circuit, pins, or related circuitry, etc. The logic circuitry is used to execute methods from any of the first to eighth aspects and their respective designs.

[0054] In one implementation, the communication device is a wireless communication device, which can be a terminal device such as a mobile phone, or it can be a satellite. The interface circuit can be a radio frequency processing chip in the wireless communication device, and the processing circuit can be a baseband processing chip in the wireless communication device.

[0055] In one implementation, when the communication device is a chip or chip system, the input circuit can be an input pin, the output circuit can be an output pin, and the logic circuit can be a transistor, gate circuit, flip-flop, or various other logic circuits. The input signal received by the input circuit can be received and input by, for example, but not limited to, a receiver, and the signal output by the output circuit can be, for example, but not limited to, output to a transmitter and transmitted by the transmitter. Furthermore, the input circuit and the output circuit can be the same circuit, which is used as both the input circuit and the output circuit at different times. This application does not limit the specific implementation of the input / output interface and the logic circuit.

[0056] The aforementioned communication device can be a terminal device (or satellite, MME / AMF), or a component / part of a terminal device (or satellite, MME / AMF). For example, the communication device can be a communication module and / or computing module of the terminal device (or satellite, MME / AMF); or the communication device can be a circuit or chip (such as a modem chip, or a SoC chip or SIP chip containing a modem core) in the terminal device (or satellite, MME / AMF) responsible for communication functions; or the communication device is a circuit or chip (such as a CPU, DSP, ASIC, or FPGA) in the terminal device (or satellite, MME / AMF) responsible for communication and / or computing functions; or the communication device is a logic node, logic module, or software capable of implementing all or part of the functions of the terminal device (or satellite, MME / AMF). The chip system can be composed of chips or can include chips and other discrete devices.

[0057] In a thirteenth aspect, a communication system is provided, comprising a terminal device, a satellite, and a core network device. The terminal device is used to implement the functions described in the first aspect. For example, the core network device sends a NAS message, and the satellite sends a system message; when the terminal device is in an idle state, it does not perform an AS operation before a first time. The NAS message includes a first satellite list associated with a first timer, which indicates a waiting time for retrying the NAS procedure. The system message includes a second satellite list, where each satellite in the second satellite list is associated with a service start time. The first time is the minimum of the end time of the first timer and the second time. The second time is either the minimum of the service start times associated with the second satellite list, or the service start time associated with one satellite in the second satellite list.

[0058] Alternatively, the terminal device may be used to implement the functionality described in the second aspect. For example, the core network device sends a NAS message, and the satellite sends a system message; when the terminal device is in an idle state, it does not perform an AS operation before the second time. The NAS message includes a first satellite list associated with a first timer, which indicates the waiting time for retrying the NAS procedure. The system message includes a second satellite list, where each satellite in the second satellite list is associated with a start service time, and the second satellite list contains the first satellite list. The second time is the minimum of the start service times associated with the second satellite list, or the second time is the start service time associated with one satellite in the second satellite list.

[0059] Alternatively, the terminal device may implement the functions described in the third aspect, and the core network device may implement the functions described in the fifth aspect. For example, the core network device sends a NAS message; the terminal device, based on the NAS message, executes the procedure to access the first satellite. The NAS message includes a first timer and / or a first satellite list. The first timer indicates the waiting time for retrying the NAS procedure, and the first timer is associated with a first satellite, which is the first available satellite capable of obtaining the context of the terminal device. The first satellite list includes a first satellite, which is the first satellite among the satellites after the terminal device leaves the current satellite capable of obtaining the context of the terminal device.

[0060] Alternatively, the terminal device may implement the functions described in the fourth aspect, and the satellite may implement the functions described in the sixth aspect. For example, the satellite transmits a system message; the terminal device, based on the system message, executes the procedure of accessing satellites in the second satellite list. The system message includes the second satellite list. Wherein, the satellite transmitting the system message operates in normal mode, and the second satellite list includes only satellites operating in normal mode. Alternatively, the satellite transmitting the system message operates in store-and-forward mode, and the second satellite list includes satellites operating in normal mode and / or satellites operating in store-and-forward mode.

[0061] In a fourteenth aspect, a computer-readable storage medium is provided, which stores a computer program or readable instructions, such that when a computer reads and executes the computer program or readable instructions, the computer performs the method described in any of the first to eighth aspects and any of their designs.

[0062] In a fifteenth aspect, a computer program product is provided, which, when read and executed by the settlement price, causes a computer to perform the method described in any of the first to eighth aspects and any one of their designs.

[0063] The beneficial effects of aspects nine through fifteen above can be referenced to the beneficial effects of aspects one through eight and any one of their designs. Attached Figure Description

[0064] Figures 1A to 1D are schematic diagrams of several satellite system architectures;

[0065] Figure 2 is a schematic diagram of the satellite's storage and forwarding modes.

[0066] Figure 3 is a schematic diagram of the UE's network access process in the satellite storage and forwarding mode;

[0067] Figure 4 is a schematic diagram of the architecture of a satellite communication system;

[0068] Figure 5 is a flowchart illustrating the first communication method provided in an embodiment of this application;

[0069] Figure 6 is a flowchart illustrating the second communication method provided in an embodiment of this application;

[0070] Figure 7 is a flowchart illustrating the second communication method provided in an embodiment of this application;

[0071] Figure 8 is a flowchart illustrating the second communication method provided in an embodiment of this application;

[0072] Figure 9 is a schematic diagram of a communication device provided in an embodiment of this application;

[0073] Figure 10 is a schematic diagram of another structure of the communication device provided in an embodiment of this application. Detailed Implementation

[0074] In the embodiments of this application, "transmission" includes "sending" and / or "receiving". "Sending" and "receiving" indicate the direction of signal transmission. "Sending" can also be understood as the "output" of the chip interface, and "receiving" can also be understood as the "input" of the chip interface.

[0075] For example, "sending information" can occur between devices or between logical modules (such as components, modules, chips, software modules, or hardware modules) within a device. For instance, "satellite sending information" can be understood as a satellite sending information to another device (such as a terminal device), or it can be understood as logical module 1 in a satellite sending information to logical module 2 in the satellite.

[0076] Similarly, "receiving information" can occur between devices or between logical modules (such as components, modules, chips, software modules, or hardware modules) within a device. For example, "satellite receiving information" can be understood as a satellite receiving information from another device (such as a terminal device), or it can be understood as logical module 1 in a satellite receiving information from logical module 2 in the satellite.

[0077] For example, phrases like "sending information to XX (e.g., a terminal device)" or the transmission-related illustrations in the accompanying drawings can be understood as the destination of the information being XX, including sending information directly or indirectly to XX. Similarly, phrases like "receiving information from YY (e.g., a satellite)," "receiving information from YY (e.g., a satellite)," or "receiving information sent by YY (e.g., a satellite)," or the reception-related illustrations in the accompanying drawings, can be understood as the source of the information being YY, including receiving information directly or indirectly from YY. Furthermore, information may undergo necessary processing between the source and destination, such as format changes, but the destination can understand the valid information from the source. Similar expressions in this application can be interpreted similarly and will not be elaborated further here.

[0078] In this application embodiment, the number of nouns, unless otherwise specified, refers to "singular nouns or plural nouns," that is, "one or more." "At least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, or B exists alone, where A / B can be singular or plural. The character " / " generally indicates that the related objects before and after are in an "or" relationship. For example, A / B means: A or B. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, and / or c means the following combinations: a exists alone, b exists alone, c exists alone, a and b exist simultaneously, a and c exist simultaneously, b and c exist simultaneously, or a, b, and c exist simultaneously, where a, b, and c can be single or multiple.

[0079] In the embodiments of this application, "when," "if," and "if" all refer to the device taking corresponding actions under certain objective circumstances, not to a time limit, nor to requiring the device to perform a judgment action, nor implying any other limitations. Unless otherwise specified, "if" and "if" are interchangeable, and "when" is interchangeable with "in the case of," "if" / "if." Words such as "exemplary" or "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being better or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner. Furthermore, "of," "corresponding (relevant)," and "corresponding" can sometimes be used interchangeably, and it should be noted that their intended meanings are consistent when their distinctions are not emphasized. In the embodiments of this application, "corresponding" can also be replaced with "corresponding," "associated," or "mapped." "A and B correspond" can be understood as "A and B have an association / correspondence relationship". There are no restrictions on the specific implementation form of the correspondence / association relationship. For example, the correspondence relationship can be a mapping table, a function relationship, etc.

[0080] In embodiments of this application, "for indicating" can include both direct and indirect indication. For example, when describing a certain indication information as indicating information I, it can include whether the indication information directly indicates I or indirectly indicates I, but does not necessarily mean that the indication information carries I.

[0081] The terms "first," "second," "#1," "#2," and "#A" used in this application's embodiments are merely for descriptive convenience and to distinguish multiple objects. They are not intended to limit the size, content, order, timing, priority, or importance of the multiple objects. For example, the first satellite list and the second satellite list refer to two different data units and do not indicate a difference in priority or importance between the two satellite lists.

[0082] To facilitate understanding of the solutions provided in the embodiments of this application, the relevant terms / concepts involved in the embodiments of this application will be explained below.

[0083] (1) Access network equipment

[0084] In this embodiment, the access network device refers to a radio access network (R)AN device / RAN node. R)AN and RAN are interchangeable; for ease of description, RAN is used as an example below. RAN can be a cellular system related to the 3rd generation partnership project (3GPP), such as a 5th generation (5G) mobile communication system / new radio (NR) communication system, or a future-oriented evolution system. RAN can also be an open RAN (O-RAN or ORAN), a cloud radio access network (CRAN), a virtualized RAN (vRAN), or an NTN (e.g., a satellite communication system), etc. RAN can also be a communication system that integrates two or more of the above systems.

[0085] In one possible scenario, a RAN node can be a base station, an evolved NodeB (eNodeB), an access point (AP), a transmission reception point (TRP), a next-generation nodeB (gNB), a satellite, or a base station in a future mobile communication system. Among these, a gNB can be interchangeable with a next-generation radio access network (NG-RAN). RAN nodes can also be macro base stations, micro base stations, indoor stations, relay nodes, donor / host nodes, or radio controllers. RAN nodes can also be servers, wearable devices, vehicles, or in-vehicle equipment. For example, in vehicle-to-everything (V2X) technology, the RAN node can be a roadside unit (RSU). An AP can serve as the central hub of this communication system and can be a base station with a Wi-Fi chip, a router, a gateway, a repeater, a communication server, a switch, or a bridge. RAN nodes can also be satellites (or satellite base stations) or high altitude platform stations (HAPS), or base station equipment mounted on satellites / HAPS. Satellites can include at least one of the following: geostationary earth orbit (GEO) satellites (or geosynchronous orbit satellites) or non-geostationary earth orbit (NGEO) satellites. Non-geostationary earth orbit satellites can include at least one of the following: medium earth orbit (MEO) satellites or low earth orbit (LEO) satellites. There are no restrictions here. RAN nodes can also be gateway stations (or ground stations, earth stations, signaling stations, gateways, or gateway stations).

[0086] RAN equipment can also be called RAN nodes, RAN entities, or access nodes, etc. In future scenarios, RAN nodes may also evolve into other forms; for example, RAN nodes may not be distinguished from core network equipment and may be collectively referred to as network equipment. Unless otherwise specified, in the embodiments of this application, access network equipment and network equipment can be used interchangeably, or network equipment may refer to access network equipment.

[0087] In another possible scenario, the RAN node can be a module or unit that performs some of the functions of the base station; or multiple RAN nodes can cooperate to assist terminal equipment in achieving wireless access, with different RAN nodes performing some of the functions of the base station. For example, the RAN node can be a CU, DU, or RU. The function of the CU can be implemented by a single entity or by different entities. For example, the function of the CU can be further divided, that is, the control plane and the user plane can be separated and implemented by different entities, namely the control plane CU entity (i.e., CU-control plane (CP) entity) and the user plane CU entity (i.e., CU-user plane (UP) entity). The CU-CP entity and the CU-UP entity can be coupled with the DU to jointly complete the function of the RAN node. The CU and DU can be set up separately or included in the same network element, such as in the baseband unit (BBU). Any of the units among the CU (or CU-CP, CU-UP), DU, and RU in this application can be implemented by software modules, hardware modules, or a combination of software modules and hardware modules.

[0088] In different systems, CU (or CU-CP and CU-UP), DU, or RU may have different names, but those skilled in the art will understand their meaning. For example, in an ORAN system, CU can also be called O-CU (open CU), DU can also be called O-DU, CU-CP can also be called O-CU-CP, CU-UP can also be called O-CU-UP, and RU can also be called O-RU. For ease of description, this application uses CU, CU-CP, CU-UP, DU, and RU as examples.

[0089] The CU and DU can be configured according to the protocol layer functions of the wireless network they implement. For example, the CU can be configured to implement the functions of the Packet Data Convergence Protocol (PDCP) layer and higher protocol layers (such as the Radio Resource Control (RRC) layer and / or the Service Data Adaptation Protocol (SDAP) layer). The CU connects to network nodes such as the core network through interfaces, which can be E2 interfaces. Optionally, the CU can have some core network functions. The CU (e.g., the PDCP layer and higher) connects to the DU (e.g., the Radio Link Control (RLC) layer and lower layers) through interfaces. For example, the DU can be configured to implement the functions of protocol layers below the PDCP layer (e.g., RLC, Medium Access Control (MAC) layer, and / or Physical (PHY) layer). For specific descriptions of the above protocol layers, please refer to the relevant 3GPP technical specifications or the technical specifications of other applicable communication protocols.

[0090] The above division of CU and DU processing functions according to the protocol layer is merely an example; other division methods are also possible, and this application does not impose any restrictions.

[0091] For example, in one design, the CU or DU can be further divided into processing functions with protocol layers. In one design, some functions of the RLC layer and the protocol layer functions above the RLC layer are located in the CU, while the remaining functions of the RLC layer and the protocol layer functions below the RLC layer are located in the DU. In another possible design, the DU and RU cooperate to implement the PHY layer functions, or it can be described as moving some of the PHY layer functions of the DU to the RU. A DU can be connected to one or more RUs. The functions of the DU and RU can be configured in various ways depending on the design. For example, the DU is configured to implement baseband functions, and the RU is configured to implement mid-RF functions. As another example, the DU is configured to implement higher-level functions in the PHY layer, and the RU is configured to implement lower-level functions in the PHY layer, or to implement both lower-level and RF functions.

[0092] In the embodiments of this application, all or part of the functions of the RAN node can also be implemented through software functions running on hardware, or through virtualization functions instantiated on a platform (e.g., a cloud platform). The RAN node may also be equipped with communication modules, circuits, or chips that perform corresponding communication functions. The RAN node may also be configured with program instructions for performing corresponding communication functions and corresponding program instructions. The RAN node in the embodiments of this application may also be a logical node, logical module, or software capable of implementing all or part of the access node functions, or a circuit or chip (such as a GPU, AI processor, NPU, ASIC, or FPGA) responsible for communication and / or computing functions in the access node.

[0093] When the RAN is O-RAN, it can also have artificial intelligence (AI) capabilities. For example, O-RAN includes an intelligent controller. The intelligent controller can be a non-real-time RAN intelligent controller (RIC / non-RT RIC / NRT RIC) or a near-real-time RAN intelligent controller (RIC / near-RT RIC / nRT RIC). A non-real-time RIC can be used to implement non-real-time intelligent management of RAN functions, enabling workflows including model training and model updates, and guiding applications / functions in the nRT RIC based on policies. A near-real-time RIC can be used to implement near-real-time intelligent management of the RAN. Through data collection and related operations on the E2 interface, near-real-time control and optimization of O-RAN modules and resources are achieved.

[0094] (2) Terminal equipment

[0095] In this application embodiment, anything capable of data communication with a base station can be considered a terminal device. A terminal device is also called a terminal, terminal equipment, UE, user equipment, mobile station, or mobile terminal, etc. Terminal devices can be widely used in various scenarios. For example, a terminal device can be: a mobile phone, computer, mobile internet device (MID), wearable device, virtual reality (VR) device, augmented reality (AR) device, station (STA), robotic arm, camera, robot, vehicle, drone, or smart home device (e.g., television, air conditioner, robot vacuum cleaner, speaker), relay, customer premises equipment (CPE), etc. Among these, an STA can be a mobile phone, tablet computer, smart TV, smart wearable device, vehicle communication device, router, switch, etc., that supports Wi-Fi communication. Terminal equipment can also be a communication module, satellite phone, or its components with satellite communication capabilities, or a satellite communication terminal, such as a very small aperture terminal (VSAT) (commonly referred to as a VSAT terminal), portable station, fixed station, vehicle-mounted or airborne satellite communication terminal, etc. It should be understood that a satellite communication terminal can serve as a micro base station to further provide data interfaces to accessed user equipment.

[0096] The embodiments of this application do not limit the specific technology or device form used in the terminal device. Furthermore, in the embodiments of this application, the terminal device can also be a terminal device in an IoT system, such as a water meter or electricity meter. When the terminal device is applied to V2X, it can also be called a V2X device. The various terminal devices described above, if located on a vehicle (e.g., placed / installed inside a vehicle), can all be considered in-vehicle terminal devices. In-vehicle terminal devices can be built into a vehicle's in-vehicle module, in-vehicle module, in-vehicle component, in-vehicle chip, or in-vehicle unit as one or more components or units. The vehicle can implement the methods of this application through the built-in in-vehicle module, in-vehicle module, in-vehicle component, in-vehicle chip, or in-vehicle unit. In-vehicle terminal devices can be vehicle equipment, in-vehicle modules, vehicles, on-board units (OBU), remote sensing units (RSU), vehicle infotainment systems (or in-vehicle transmission units) (telematics boxes, T-boxes), chips, or system-on-chips (SoCs), etc. The aforementioned chips or SoCs can be installed in the vehicle, OBU, RSU, or T-box.

[0097] (3) Core Network

[0098] In this application, the core network may include equipment that processes and forwards user signaling and data. This includes, for example, core network equipment such as MME, AMF network elements, and user plane gateways. The user plane gateway can be a server with functions such as mobility management, routing, and forwarding of user plane data, typically located on the network side, such as a user plane function (UPF) network element. The core network may also include other network elements, which are not listed here.

[0099] In this application, the communication device used to implement the functions of core network equipment can be referred to as a core network device. This core network device can be a core network element, a core network device, or a device capable of supporting the core network device or network element in implementing the function, such as a chip system. This device can be installed in the core network device. In the technical solutions provided in the embodiments of this application, the core network device is used as an example to describe the technical solutions provided in the embodiments of this application. Additionally, a network element can also be referred to as an entity or functional entity. For example, an MME can also be referred to as an MME entity or an MME functional entity. Optionally, the core network device name mentioned in the embodiments of this application can omit "entity." For example, MME entity and MME have the same meaning. Furthermore, a network element / functional entity can be a network component in a hardware device, a software function running on dedicated hardware, or a virtualized function instantiated on a platform (e.g., a cloud platform). Optionally, the aforementioned network element or functional entity can be implemented by one device, or by multiple devices, or can be different functional modules within a single device. The embodiments of this application do not specifically limit this.

[0100] (4) Satellites and their operating modes

[0101] In this embodiment, the satellite can be a HEO satellite, a GEO satellite, a MEO satellite, or a low-Earth orbit (LEO) satellite. The link between the satellite and the terminal device is called a service link, and the link between the satellite and the network device is called a feeder link. Satellites have various operating modes, including transparent mode and regenerative mode, which are described below.

[0102] In pass-through mode, the satellite acts as an analog radio frequency repeater with relay forwarding capabilities. It can perform wireless frequency conversion and amplification, and can pass through or copy signals between ground base stations and terminal equipment.

[0103] Figure 1A illustrates a transparent satellite architecture. The satellite's role is radio frequency filtering, frequency conversion, and amplification; essentially, it acts as a Layer 1 relay, regenerating physical layer signals without involving higher protocol layers. The satellite communicates wirelessly with ground gateways (also called ground stations, earth stations, or gateways), which are connected to ground base stations via wired connections. The UE accesses the ground base station via the air interface. The satellite and the ground gateway forward signals between the UE and the ground base station. The ground base station connects to the core network, which in turn communicates with the data network (DN). In this architecture, the satellite can be understood as a remote radio unit (RRU) of the ground base station. The satellite provides simple physical signal coverage, but the remote radio function requires the gateway and the microwave link between the satellite and the gateway to reach the satellite. No protocol layer processing or logical interface is established during this process. One or more satellites can connect to one or more ground base stations through one or more gateways. In transparent transmission mode, the gateway possesses some or all of the functions of a base station, and in this case, the gateway can be considered as a base station. It can be assumed that the gateway and base station can be deployed together or separately. If the gateway and base station are deployed separately, then the latency of the feeder link includes the latency from the satellite to the gateway and the latency from the gateway to the base station.

[0104] Regeneration mode refers to a satellite acting as a wireless communication base station, possessing some or all of the functions of a base station, or having some or all of the functions of a base station deployed on a satellite, which can process signals received from the ground and regenerate those signals.

[0105] Figure 1B illustrates a regenerative satellite architecture (RAN architecture with transparent satellite). The UE communicates with the satellite via an air interface (e.g., the Uu interface), the satellite communicates with the core network via the NG interface, and the core network communicates with the DN via the N6 interface. The satellite functions as a base station (e.g., handling all protocol layers of a base station). The satellite transmits back to a ground gateway via microwave, and the gateway is connected to the core network via a wired connection. The link between the satellite and the gateway can be called a satellite radio interface (SRI) or a feeder link. In the architecture shown in Figure 1B, there is no inter-satellite link (ISL) between satellites.

[0106] Figure 1C illustrates a regenerative satellite architecture (RAN architecture with transparent satellite). The difference between Figure 1C and Figure 1B is that in the architecture shown in Figure 1C, satellites communicate with each other via an ISL (Integrated Satellite Link), which can be deployed on the ISL. When a satellite cannot connect to the ground gateway, it can establish Xn interface communication with other satellites through the ISL and transmit its data back to the ground via these other satellites.

[0107] Optionally, the regenerating satellite has the processing function of the DU (Distributed Unit) of the base station, as shown in Figure 1D. In this architecture, the ground base station can be viewed as a separate architecture of CU (Combined Unit) and DU, and the satellite has the DU function of the ground base station.

[0108] Optionally, the regenerating satellite has the functionality of an integrated access and backhaul (IAB) node. In this architecture, the satellite, in addition to its DU (Dedicated Access Node) function, also has a mobile termination (MT) function. The satellite can use the air interface between the MT and the ground base station for backhaul, eliminating the need to establish a separate microwave backhaul link between the satellite and the gateway.

[0109] (5) Satellite coverage of the ground

[0110] Satellite coverage of the Earth can take two forms: quasi-geostationary cells and moving cells. A quasi-geostationary cell, also known as a fixed cell, maintains coverage of a specific area of ​​Earth for a period of time while the satellite is moving. The coverage area changes only when the Earth's curvature or minimum elevation angle constraints are not met; therefore, it is quasi-stationary relative to the Earth. In a moving cell, the satellite's coverage area changes as the satellite moves.

[0111] (6) The satellite's store and forward mode, or simply store and forward mode.

[0112] Store-and-forward mode is a feature introduced in 3GPP Rel-19 (R19) NTN. Satellite regeneration modes can be further divided into store-and-forward mode and non-store-and-forward mode (also referred to as normal mode in this paper). Store-and-forward mode can be abbreviated as S&F mode or SF mode.

[0113] The Store-and-Forward (SF) mode was introduced due to the limited number of ground gateway stations. Figure 2 illustrates a scenario in store-and-forward mode. As can be seen from Figure 2, due to the limited number of ground gateway stations (such as gateway station #1 and gateway station #2), it's impossible to maintain a continuous connection between a ground gateway station and the satellite covering the UE, thus preventing communication with the core network. For example, at time t1, satellite #1 can connect to gateway station #1. As satellite #1 moves, at time t2, there is no gateway station that can connect to satellite #1. At time t3, satellite #1 can connect to gateway station #2. Alternatively, even when the satellite can connect to both a gateway station and the core network, the UE may not be within the satellite's coverage area. For example, at time t3, satellite #1 can connect to gateway station #2, but the satellite does not cover the UE. Therefore, real-time service transmission is impossible. For non-real-time services, when the satellite covers the UE but has not yet connected to a ground gateway station, communication between the satellite and the UE can begin. Once the satellite connects to the ground gateway station, communication between the satellite and the core network can then commence. For example, at time t2, the satellite and the UE communicate; at time t3, the satellite connects to the ground gateway station and then communicates with the core network. However, this requires the satellite to have certain storage and processing capabilities, such as the ability to store data from the UE or the core network and then forward the stored data later.

[0114] Satellites in store-and-forward mode deploy not only some or all of the base station's functions but also some or all of the core network's functions. An architecture where all core network elements are deployed on a satellite is called "whole CN on-board," while an architecture where some core network elements are deployed on a satellite is called "split MME on-board." In the whole CN on-board architecture, all core network elements are deployed on each satellite, resulting in minimal impact on the access network. In the split MME on-board architecture, some MMEs are deployed on the satellite, while others, along with other core network elements (such as the Home Subscriber Server (HSS),), are deployed on the ground. The MMEs on the satellite and those on the ground are not functionally distinct and can be considered as the same MME. Alternatively, the MME on the satellite can have all the functions of an MME. When the satellite and the ground feeder link are connected, the MME on the satellite and the ground MME are the same MME. When the satellite and the ground feeder link are not connected, the MME on the satellite can independently process NAS messages (or messages between the UE and the MME), but cannot independently process messages between the ground MME and other core network elements.

[0115] The following section uses the split MME on-board architecture as an example to introduce the UE's network access process. As shown in Figure 3, the UE's network access process includes the following steps:

[0116] T1: At time T1, satellite #1 covers the UE, and the UE sends a NAS message (e.g., an attach request) to MME #1 via eNB #1 to request network access. Upon receiving the attach request, MME #1, since the UE's HSS is on the ground, does not know whether the UE is a legitimate UE, so it first replies with an attach reject message. Optionally, the attach reject message carries a monitoring list of satellite IDs (e.g., including satellite 2) for subsequent coverage of the UE, and / or a wait timer (T4) for the arrival of the next satellite (satellite 2). The monitoring list of satellite IDs (or satellite ID list) and the wait timer are both sent by the MME to the UE's NAS layer via the NAS message; the eNB and the UE's AS layer do not process them, only pass them through. The satellite ID is carried in the SIB31 system broadcast. Each satellite broadcasts its own satellite ID in the SIB31. The UE reads the SIB31 of the currently covered satellite to determine whether the satellite ID is in the satellite ID list configured in the NAS, and decides whether to access the currently covered satellite.

[0117] T2: Satellite #1 covers the ground gateway station and establishes a connection with the ground core network. It forwards the information sent by the UE to MME #1 at time T1 to the ground core network elements, such as sending the UE information to HSS for authentication.

[0118] T3: When satellite #2 is connected to the gateway station, back up the UE's context (such as the UE's registration information) on the core network side to MME #2.

[0119] T4: After satellite #2 covers the UE, the UE attempts to attach request to MME #2 again. The UE includes its subscription permanent identifier (SUPI) in the attach request message. Based on the UE's SUPI, MME2 determines that the UE's context has been synchronized to MME #2 at time T3, and that the UE authentication is successful, then replies with an attach accept message to the UE. At this point, the UE's registration process is complete, and the UE and MME #2 can transmit data. For example, the UE stores data in MME #2. When data transmission is complete, or when satellite 2 is about to leave the UE, eNB #2 sends an RRC release message to the UE, releasing the UE to the idle state. Optionally, MME2 continues to indicate to the UE the monitoring list of satellite IDs and the wait timer for subsequent satellites covering the UE. Afterward, the access network side (eNB #2) no longer has the UE's context, but the core network side (MME #2) considers the UE to still be in a registered state.

[0120] After T4, Satellite 2 covers the gateway station again, transmitting the stored UE data to the ground data network. When the next satellite (such as Satellite 3) connects to the gateway station, it backs up the UE's core network context (such as the UE's registration information) to MME#3, and the data network transmits the data intended for the UE to MME#3. After Satellite 3 covers the UE, since the UE has already registered, it can directly send a service request message to MME#3 without needing to send an attach request message again.

[0121] In the S&F (Satellite ID List and Wait Timer), the MME sends the satellite ID list and wait timer to the UE via unicast NAS messages. The wait timer indicates the duration of satellite coverage for the UE, and therefore applies to both fixed and moving cells. For moving cells, different NAS wait timers can be configured for different UEs.

[0122] Currently, the regulations stipulate that satellites associated with the satellite ID list and wait timer (such as satellite 2 in Figure 3) must have UE context. This is necessary for the UE to successfully attach to these satellites and for service requests to be sent to them to successfully transmit services. There are no restrictions on how satellites that previously covered the UE (also known as older satellites) determine which subsequent satellites covering the UE have UE context. For example, an older satellite might assume that if, after it covers the gateway station, and before a new satellite (such as satellite 2) covers the UE, the new satellite has a chance to obtain UE context if it covers the gateway station at least once.

[0123] Furthermore, S&F (Service & Facility) is not limited to application scenarios where only S&F satellites are present. For example, in real-world scenarios, other satellites operating in normal mode near the S&F satellite can connect to the gateway station, and the UE can access the network when these other satellites cover it. Currently, the protocol agrees to indicate the current satellite's operating mode (S&F or normal) in the system information block (SIB) 1 of the serving satellite. The transition between S&F and normal operating modes is under discussion; for example, it has been proposed that if an S&F satellite becomes able to connect to the gateway station while moving, then that satellite can switch to normal mode. This has not yet been finalized.

[0124] (7) Discontinuous coverage of satellites

[0125] Discontinuous coverage is a feature introduced in 3GPP Release 17 NTN. The number of satellites deployed in the air may be limited, resulting in discontinuous coverage of certain areas. In other words, after a satellite covering an area leaves, the next satellite covering that area will arrive (or pass over) after a certain period of time.

[0126] Release 17 introduced SIB32 for discontinuous coverage scenarios. SIB32 indicates at least one satellite (e.g., a satellite ID list) that will subsequently cover the UE, along with the ephemeris information of each satellite. In this document, "subsequent satellites" refers to satellites that cover the UE after the currently serving satellite, which covers the first area. Optionally, SIB32 can also indicate the start service time (t-ServiceStart) for each satellite ID in the satellite ID list. It should be noted that SIB32 may or may not include t-ServiceStart. For example, for satellites belonging to fixed cells in the satellite ID list, SIB32 includes the t-ServiceStart of that satellite; for satellites belonging to moving cells in the satellite ID list, SIB32 may not include the t-ServiceStart of that satellite. This is because SIB32 is cell-level, and for fixed cells, it can ensure that satellite coverage of all areas within the cell begins simultaneously. The coverage area of ​​a moving cell is variable, and it cannot indicate the start time of subsequent satellites covering the current coverage area. For example, the time when a moving cell begins covering a UE is different for a UE at the cell edge and the cell center. For a moving cell, the UE can calculate the time when each subsequent satellite will cover it based on the ephemeris information of each satellite and its own location.

[0127] The terms and concepts involved in the embodiments of this application have been introduced above. Other content related to the embodiments of this application will be introduced below.

[0128] As mentioned earlier, for the UE, the core network can configure the monitoring list of satellite IDs and wait timer via NAS messages, and can also configure the satellite ID list and the t-ServiceStart of each satellite ID in the satellite ID list via SIB32. If the monitoring list of satellite IDs and wait timer configured via NAS messages are considered as one set of satellite information, and the satellite ID list configured via SIB32 and the t-ServiceStart of each satellite ID in the satellite ID list are considered as another set of satellite information, then the UE is configured with two sets of satellite information.

[0129] The current conclusion is that the satellite ID list and wait timer configured in the NAS are only for reference. When the UE is waiting for the arrival of a satellite configured in the NAS, if a satellite in normal mode is detected, it can access the normal mode satellite to reduce network access latency. After accessing the normal satellite, the normal satellite can also configure a new satellite ID list and wait timer for the UE. If the normal satellite does not configure a new satellite ID list and wait timer for the UE, the UE will continue to wait for the arrival of the satellite indicated in the old satellite ID list and wait timer after the normal satellite service is completed.

[0130] When a UE is configured with two sets of satellite information, how to use these two configurations to achieve performance gains requires further research. For example, current regulations stipulate that in discontinuous coverage scenarios, the UE enters the RRC idle state after the previous satellite leaves. When a UE is configured with two sets of satellite information, if a satellite in normal mode is detected while the UE is waiting for the satellite configured in the NAS, it can access the normal mode satellite. To avoid missing accessible satellites, the UE typically performs operations such as cell search continuously, which is relatively energy-intensive.

[0131] Therefore, the solution provided in this application embodiment is provided. In this application embodiment, the UE can determine the satellite detection time based on the aforementioned two sets of satellite information, thereby saving UE power consumption during the access process. For example, the UE can refrain from performing AS operations (e.g., refrain from cell search) before the minimum of t-ServiceStart or the end time of the wait timer, thereby reducing power consumption. Alternatively, the UE can access the satellite after the end time of t-ServiceStart or the wait timer, thereby reducing network access latency.

[0132] The embodiments of this application can be applied to NTN, or scenarios where NTN is integrated with terrestrial networks (TN). The NTN system can be an NTN system integrated with 4G, 5G, and any future generation of communication systems, such as NR NTN, IoT NTN, etc. The NTN communication system can be, for example, a satellite communication system, and can also include drones, high-altitude platforms, and other aerial access network equipment; this application does not limit this.

[0133] This application embodiment can be applied to satellite regeneration mode. Please refer to Figure 4, which illustrates a communication system to which this application embodiment applies. The communication system includes satellites (e.g., satellites #1 to #4), gateway stations (e.g., gateway station #1 to gateway station #2), and terminal devices (e.g., terminal device #1 to terminal device #2). The number of various devices included in Figure 4 is merely an example; there may be fewer or more. Satellites within the communication system may cover the same or different areas at different times as they move, or the satellites within the communication system may include fixed-cell satellites and / or moving-cell satellites. Satellites within the communication system may or may not have connected ground gateway stations. As shown in Figure 4, satellite #1 can be connected to gateway station #1, satellite #4 can be connected to gateway station #2, and satellites #2 and #3 do not have connectable gateway stations. Satellites within the communication system may or may not cover terminal devices. As shown in Figure 4, satellite #1 covers terminal device #1, satellite #3 covers terminal device #2, and satellites #2 and #4 do not cover terminal devices. Understandably, as the satellite moves, the gateway stations that can connect to the satellite will differ, and the terminal devices covered by the satellite will also differ.

[0134] The communication system shown in Figure 4 is for illustrative purposes only and does not constitute a limitation on the communication systems applicable to the embodiments of this application. For example, the communication system may also include other devices, such as base stations, which are not shown in Figure 4. Those skilled in the art will recognize that the technical solutions provided in the embodiments of this application are equally applicable to similar technical problems as network architectures evolve. When applying the technical solutions of the embodiments of this application to other communication systems, the devices, components, and modules in the embodiments can be replaced with corresponding devices, components, and modules in other communication systems without limitation.

[0135] In the embodiments of this application, "not performing AS operation" can be replaced by "suspending AS operation" or "stopping AS operation". AS operation includes one or more of the following: cell search, synchronization, SIB decoding, and random access during initial access; RRC establishment and release, paging detection, cell handover, cell reselection, and authentication during connection management.

[0136] In the embodiments of this application, for the UE, the subsequent satellite is relative to the current time (currently serving satellite), and the start time of the subsequent satellite is later than the start time of the current serving satellite.

[0137] In the embodiments of this application, "predefined" may refer to a standard protocol predefined, or it may refer to a pre-agreed or pre-negotiated agreement between devices. Here, "protocol" can refer to standard protocols in the field of communications, such as 4G network protocols, 5G network protocols, NR protocols, 5.5G network protocols, and related protocols applied in future communication networks; this application does not limit this.

[0138] In embodiments of this application, (pre)configuration includes configuration via RRC messages, downlink control information (DCI), or MAC control element (CE).

[0139] The method provided in the embodiments of this application is described below with reference to the accompanying drawings and specific examples.

[0140] The methods in this application are executed by satellite, core network equipment, and terminal equipment. The various embodiments herein can be applied to the network architectures shown in Figures 1B-1D or 4. For example, the satellites described in the various embodiments herein can be the satellites shown in Figures 1B-1D or 4. The core network equipment described in the various embodiments herein can be equipment in the core network shown in Figures 1B-1D or 4, such as an MME or AMF. The terminal equipment described in the various embodiments herein can be a UE or terminal equipment shown in Figures 1B-1D or 4. In the accompanying drawings corresponding to the various embodiments of this application, steps indicated by dashed lines are optional steps. Furthermore, the step numbering in the various embodiments described in this application is only for distinguishing different steps and is not intended to limit the order of steps.

[0141] The steps performed by the satellite can also be performed by circuits or chips within the satellite responsible for communication functions (such as modem chips (also known as baseband chips), or SoC chips or SIP chips containing modem cores), chip systems, or processors); or by circuits or chips within the satellite responsible for communication and / or computing functions (such as CPUs, ASICs, or FPGAs); or by logic nodes (or logic modules) and / or software implementing all or part of the satellite's functions. Optionally, the satellite can be replaced by aerial equipment such as drones or high-altitude aircraft.

[0142] The steps performed by the terminal device can also be performed by the circuits or chips in the satellite responsible for communication functions (such as modem chips (also known as baseband chips), or SoC chips or SIP chips containing modem cores), chip systems, or processors; or by the circuits or chips in the terminal device responsible for communication and / or computing functions (such as CPUs, ASICs, or FPGAs); or by the logical nodes (or logical modules) and / or software that implement all or part of the functions of the terminal device.

[0143] The core network equipment, such as MME or AMF, can perform the steps by the core network equipment. These steps can also be performed by circuits or chips (such as SoC chips or SIP chips), chip systems, or processors in the core network that are responsible for communication functions. Alternatively, they can be performed by circuits or chips (such as CPUs, ASICs, or FPGAs) in the core network equipment that are responsible for communication and / or computing functions. Or, the software can be implemented by logical nodes (or logical modules) and / or software that implement all or part of the functions of the terminal equipment.

[0144] Furthermore, the processing performed by a single execution entity can also be divided into multiple execution entities, which can be logically and / or physically separated.

[0145] Example 1

[0146] Please refer to Figure 5, which is a flowchart illustrating the first communication method provided in this embodiment. Figure 5 describes the method from the perspective of interaction between the satellite, core network equipment, and terminal equipment.

[0147] S501, the core network device sends a NAS message to the terminal device, and the terminal device receives the NAS message from the core network device accordingly.

[0148] This NAS message includes a first satellite list, which indicates which satellites the terminal device should retry the NAS process or receive data from. The first satellite list is sent by the core network device to the NAS layer of the terminal device via a NAS message, indicating which satellites the terminal device needs to monitor or prioritize connecting to. For example, the first satellite list may include the identifiers (IDs) of subsequent satellites. The first satellite list is the aforementioned "monitoring list of satellite IDs," and can also be called the NAS satellite ID list.

[0149] The first satellite list is associated with a first timer, which indicates the waiting time for retrying the NAS process, or instructs the terminal device to continuously monitor the satellites in the first satellite list until the first timer expires. For example, the first timer could be the "wait timer" mentioned above, indicating the time when the first satellite in the first satellite list arrives.

[0150] Optionally, the NAS message also includes a first timer. Flexibly configuring the first timer through the NAS message helps the network side dynamically adjust the waiting time for each terminal device to retry the NAS process, reducing network congestion and avoiding increased signaling interaction caused by frequent NAS process attempts by terminal devices. For example, if current network resources are limited, a longer first timer can be configured to prevent terminal devices from failing to access the network due to insufficient resources and subsequently retrying the NAS process.

[0151] Optionally, the NAS message does not include the first timer. After obtaining the first satellite list, the terminal device can attempt to access satellites in the first satellite list without waiting for the first timer to expire, reducing the implementation complexity of generating the first timer value on the network side. Alternatively, the first timer can be pre-configured in the terminal device or predefined through the protocol, eliminating the need for core network devices to configure it. In IoT NTN scenarios, the IoT terminal device searches for satellites before the first timer expires each time it wakes up, preventing excessively long search times and wasted energy.

[0152] S502, Satellite Transmission System Message, and correspondingly, the terminal equipment receives the system message.

[0153] The execution order of S502 and S501 is not restricted. For example, S502 can be executed before S501, after S501, or simultaneously with S501.

[0154] The system message includes a second satellite list, which can indicate subsequent satellites with non-contiguous coverage. For example, the second satellite list includes the IDs of subsequent satellites with non-contiguous coverage. The system message may also include ephemeris information for each satellite. Compared to the first satellite list, the second satellite list can also be called the AS satellite ID list. Existing system messages, such as SIB32, can be reused, or other system messages besides SIB32; there are no restrictions on this.

[0155] Each satellite in the second satellite list is associated with a service start time (t-ServiceStart). For example, the second satellite list includes satellite #1, satellite #2, satellite #3, satellite #4, and satellite #5. Satellite #1 is associated with t-ServiceStart#1, satellite #2 with t-ServiceStart#2, satellite #3 with t-ServiceStart#3, satellite #4 with t-ServiceStart#4, and satellite #5 with t-ServiceStart#5.

[0156] Optionally, the system message may include, in addition to the second satellite list, the start service time associated with some or all of the satellites in the second satellite list. For example, for a fixed cell satellite in the second satellite list, the system message carries the t-ServiceStart of that satellite; for a moving cell satellite in the second satellite list, the system message may not carry the t-ServiceStart of that satellite. For a moving cell, the terminal device can calculate the start service time of that satellite (or the time that covers its own) based on the satellite's ephemeris information and its own location information.

[0157] The first satellite list is configured via NAS messages, and the second satellite list is configured via system messages (or AS). These two lists are configured independently. The first and second satellite lists may be the same or different. For example, the satellite IDs in the first and second satellite lists may be exactly the same. Alternatively, some satellite IDs may be the same in both lists, such as the second list including the first list or being a subset of the first list. Another example is that the satellite IDs in the first and second satellite lists may be completely different. Completely different satellite IDs in the first and second satellite lists mean that there is no overlap between the satellite IDs in the first and second lists. Having slightly different satellite IDs in the first and second lists helps improve coverage and system capacity. For example, the second satellite list can contain more satellites than the first satellite list, thereby achieving wide-area coverage and increasing system capacity.

[0158] Optionally, it can be predefined or agreed that the satellite ID portions of the first satellite list and the second satellite list are the same or completely different. When obtaining the first satellite list and the second satellite list, the terminal device does not need to determine whether the satellite IDs contained in each list are the same; the protocol can determine whether the satellite ID portions of the first satellite list and the second satellite list are the same or completely different, thus reducing the complexity of the terminal device.

[0159] S503. When the terminal device is in an idle state, it shall not perform AS operation before the first time.

[0160] When a terminal device needs to switch satellites, it can detect subsequent satellites to execute the satellite access procedure. If the terminal device is configured with a first satellite list and a second satellite list, and the terminal device is in an idle state, it may not perform AS operations or may suspend AS operations before the first time; upon reaching or after the first time, the terminal device may execute the satellite access procedure or perform AS operations. Here, "the terminal device is in an idle state" can be replaced with "the terminal device leaves the serving satellite".

[0161] The first time can be determined based on the end time of the first timer and / or the start time associated with a satellite in the second satellite list. By constraining the first time, both the energy consumption of the terminal device can be saved, and satellite access can be achieved as early as possible, reducing network access latency. For example, the first time can be the end time of the first timer, or the minimum start time associated with the second satellite list. When the terminal device is in an idle state, it does not perform cell search or paging detection before the first time (e.g., the end time of the first timer). Compared to continuously performing operations such as cell search while waiting for satellites in the first satellite list (e.g., before the end time of the first timer), the energy consumption of the terminal device can be minimized, which is especially suitable for IoT terminal devices. While waiting for satellites in the first satellite list, satellite detection is performed based on the second satellite list configured by the system message. If a satellite is detected, the satellite access process can be executed without waiting until satellites in the first satellite list (e.g., before the end time of the first timer) to perform satellite access. Therefore, satellite access can be performed as early as possible, reducing network access latency.

[0162] The initial timing varies depending on whether the NAS message includes a first timer and whether the second satellite list is the same as the first satellite list. This initial timing difference leads to different behaviors of the subsequent terminal devices. These scenarios are described below.

[0163] In case #A, the satellite IDs in the first satellite list and the second satellite list are the same (e.g., the second satellite list includes the first satellite list), and the NAS message does not include the first timer.

[0164] In Example 1-1, the first time can be the second time. The terminal device does not perform the AS operation before the first time, which means: the terminal device does not perform the AS operation before the second time.

[0165] The second time can be the minimum value among the start service times associated with the second satellite list. Continuing with the example above, the second satellite list includes satellites #1 to #5, and the start service times associated with the second satellite list include t-ServiceStart#1 to t-ServiceStart#5. The second time is the minimum value among t-ServiceStart#1 to t-ServiceStart#5.

[0166] Alternatively, the second time can be the service start time associated with a satellite in the second satellite list. For example, the second satellite list includes satellites #1 to #5, and the associated service start times for the second satellite list include t-ServiceStart#1 to t-ServiceStart#5. The second time is any one of the t-ServiceStart times from t-ServiceStart#1 to t-ServiceStart#5. There is no specific limitation on the specific satellite mentioned. For example, the second time can be the service start time associated with a satellite in the second satellite list that meets certain conditions. For example, satellites meeting certain conditions include satellites in normal mode, or currently accessible satellites, or currently accessible satellites in normal mode.

[0167] The second satellite list includes all the satellites indicated by the NAS message in the first satellite list, which are also included in the satellites indicated by the system message. In this case, satellites are detected according to the start service time associated with the second satellite list, ensuring that no satellites in the first satellite list are missed. Therefore, AS operation can be avoided before the first time, which can both prevent missed satellites and reduce the power consumption of terminal equipment.

[0168] Assuming the terminal device detects the first satellite upon arrival, and if the first satellite is in the first satellite list, the terminal device executes the satellite access procedure, applicable to non-real-time service transmissions. Specifically, the core network device can send the first satellite list to the terminal device's NAS entity, which then sends the first satellite list to the terminal device's AS entity. The AS entity determines whether the first satellite is in the first satellite list. Alternatively, the terminal device's AS entity can send the first satellite's ID to the terminal device's NAS entity, which then determines whether the first satellite is in the first satellite list and feeds back the result to the AS entity.

[0169] Conversely, if the first satellite is not in the first satellite list, the terminal device can determine whether to execute the access procedure based on the first satellite's operating mode. For example, if the first satellite's operating mode is normal mode, the access procedure is executed; if the first satellite's operating mode is store-and-forward mode, the access procedure is not executed. When the first satellite's operating mode is normal mode, it can obtain the terminal device's context and execute the access procedure, maximizing the success rate of the terminal device's access and reducing network latency. When the first satellite's operating mode is store-and-forward mode, it may not be able to obtain the terminal device's context, and executing the access procedure would result in the terminal device's access failure. It is understandable that the terminal device can determine the first satellite's operating mode based on SIB1.

[0170] Optionally, upon reaching the fifth time, the terminal device can execute the satellite access procedure, where the fifth time is the minimum of the second and sixth times. The second time is the minimum start-service time among the satellites in the second satellite list operating in normal mode. The sixth time is the minimum start-service time of the fourth satellite in the second satellite list, and the fourth satellite is a satellite in the first satellite list. The sixth time can be considered as the minimum start-service time of the satellites in the first satellite list corresponding to those in the second satellite list. For example, the first satellite list includes {satellite #1, satellite #2, satellite #3}, and the second satellite list includes {satellite #1, satellite #2, satellite #3, satellite #4, and satellite #5}, where satellite #4 and satellite #5 in the second satellite list operate in normal mode. The start-service times associated with the second satellite list are t-ServiceStart#1 to t-ServiceStart#5, respectively. The second time is the minimum of t-ServiceStart#4 and t-ServiceStart#5, and the sixth time is the minimum of t-ServiceStart#1 to t-ServiceStart#3. Taking t-ServiceStart#4 as greater than t-ServiceStart#5, t-ServiceStart#1 as less than t-ServiceStart#2, and t-ServiceStart#1 as less than t-ServiceStart#3 as an example, then the fifth time is the minimum value between t-ServiceStart#5 and t-ServiceStart#1.

[0171] The NAS entity of the terminal device can send a first satellite list to the AS entity of the terminal device. The AS entity calculates the sixth time based on the first satellite list, and then determines the fifth time. Alternatively, the AS entity of the terminal device can send a second satellite list, along with the operating mode and associated start time of each satellite in the second satellite list, to the NAS entity. The NAS entity then calculates the sixth time, determines the fifth time, and sends the fifth time to the AS entity.

[0172] Optionally, the operating mode information of the satellites in the second satellite list can be indicated by additional signaling or information elements. For example, a system message (such as SIB32) may indicate (or include) information about the operating modes of the satellites in the second satellite list, in addition to indicating the second satellite list. The terminal device can determine the operating mode of the first satellite based on the system message. In this case, the fifth time is the same as the first time.

[0173] In Example 1-2, considering that satellites in store-and-forward mode may fail to obtain the context of the terminal device, resulting in satellite access failure, the terminal device can try to detect satellites operating in normal mode, without needing to detect satellites operating in store-and-forward mode, thereby minimizing the power consumption of the terminal device and improving the success rate of the terminal device accessing the satellite.

[0174] Specifically, when the satellite IDs in the first satellite list and the second satellite list are completely different, waiting for satellites in the first satellite list according to the end time of the first timer may result in missing satellites that were earlier than those in the first satellite list. Detecting satellites according to the second timer may also result in missing satellites in the first satellite list. Therefore, in this situation, the terminal device continues to perform AS operation to avoid missing satellites. If the currently detected satellite is the first satellite, and the first satellite is in the first satellite list, then access to the first satellite is performed directly. If the first satellite is not in the first satellite list, the access procedure for the first satellite is executed if the first satellite's operating mode is normal mode; otherwise, the access procedure for the first satellite is not executed.

[0175] Optionally, the core network device can send the first satellite list to the NAS entity of the terminal device, which then sends the first satellite list to the AS entity of the terminal device. The AS entity determines whether the first satellite is in the first satellite list. Alternatively, the AS entity of the terminal device can send the ID of the first satellite to the NAS entity of the terminal device, which then determines whether the first satellite is in the first satellite list and sends the result back to the AS entity.

[0176] In scenario B, the satellite IDs in the first and second satellite lists are either the same or completely different, and the NAS message includes a first timer. In scenario B, the first time can be the minimum of the end time of the first timer and the second time. The second time is described below with a specific example.

[0177] In Example 2-1, the second time can be the minimum value among the start service times associated with the second satellite list. For example, the second satellite list includes satellites #1 to #5, and the start service times associated with the second satellite list include t-ServiceStart#1 to t-ServiceStart#5. The second time is the minimum value among t-ServiceStart#1 to t-ServiceStart#5. Since the first time is the minimum value between the end time of the first timer and the second time, even if the satellite IDs in the first and second satellite lists are not exactly the same, detecting satellites according to the earliest time can avoid missing satellites and allow for early network access. Furthermore, by not performing AS operations (such as cell search, paging detection, etc.) between the first time, the power consumption of the terminal device can be reduced.

[0178] Alternatively, the second time can be the service start time associated with a satellite in the second satellite list. For example, the second satellite list includes satellites #1 to #5, and the service start times associated with the second satellite list include t-ServiceStart#1 to t-ServiceStart#5. The second time is any one of the t-ServiceStart times from t-ServiceStart#1 to t-ServiceStart#5. Optionally, the second time is the service start time associated with a satellite in the second satellite list that meets certain conditions. For example, satellites meeting certain conditions include satellites in normal mode, or currently accessible satellites, or currently accessible satellites in normal mode.

[0179] If the end time of the first timer is later than the second time, then the first time becomes the second time. Assuming the terminal device detects the first satellite after the second time (i.e., the first time), if the first satellite's operating mode is normal, the access procedure for the first satellite is executed; if the first satellite's operating mode is store-and-forward mode, the access procedure is not executed. When the first satellite's operating mode is normal, it can obtain the terminal device's context and execute the access procedure, thus maximizing the success rate of the terminal device's access. When the first satellite's operating mode is store-and-forward mode, it may not be able to obtain the terminal device's context, and executing the access procedure would result in the terminal device's access failing. It is understandable that the terminal device can determine the first satellite's operating mode based on SIB1.

[0180] Optionally, if the access procedure for the first satellite is not executed, no AS operation is performed before the third time. The third time is the minimum of the end time of the first timer and the fourth time, and the fourth time is the minimum of the start service times of satellites in the second satellite list that are greater than the second time. Alternatively, the fourth time is the minimum of the second satellite list excluding the second time. Upon reaching the third time, assuming the terminal device is currently detecting the second satellite, if the second satellite's operating mode is normal mode, the access procedure for the second satellite is executed; if the second satellite's operating mode is store-and-forward mode, the access procedure for the second satellite is not executed. If the access procedure for the second satellite is not executed, no AS operation is performed before the next start service time in the second satellite list, and this cycle continues.

[0181] In Example 2-2, the second time is the minimum service start time associated with satellites operating in normal mode in the second satellite list. That is, the second time is the minimum service start time associated with at least one satellite in the second satellite list operating in normal mode.

[0182] Information about the operating modes of satellites in the second satellite list can be indicated through additional signaling or information elements. For example, a system message (such as SIB32) may indicate (or include) information about the operating modes of satellites in the second satellite list, in addition to indicating the second satellite list itself. The terminal device can determine the operating mode of the first satellite based on the system message.

[0183] The first time is the minimum of the end time of the first timer and the second time. The NAS entity of the terminal device can send the first satellite list to the AS entity of the terminal device, and the AS entity determines the first time based on the first satellite list. Alternatively, the AS entity of the terminal device can send the second satellite list, along with the operating mode and associated service start time of each satellite in the second satellite list, to the NAS entity, which then determines the first time and sends it to the AS entity.

[0184] Considering that satellites in store-and-forward mode may fail to acquire the context of the terminal device, leading to satellite access failure, the terminal device can prioritize detecting satellites operating in normal mode, eliminating the need to detect those in store-and-forward mode. This minimizes the terminal device's power consumption and increases the success rate of satellite access. Accordingly, the second time can be the minimum service start time associated with satellites operating in normal mode in the second satellite list. The terminal device uses the minimum of the end time of the first timer and the second time (i.e., the first time) as a reference. Before the first time, no AS operation is performed; after the first time, the satellite access process can be executed. This approach minimizes terminal device power consumption and allows for early network access.

[0185] If the end time of the first timer is no later than the second time, or if the end time of the first timer is earlier than the second time, then the first time is the end time of the first timer. The terminal device does not perform AS operation before the first time (i.e., the end time of the first timer); after the first time is reached, it executes the satellite access procedure without waiting for the end time of the first timer, thereby reducing network access latency.

[0186] In case C, the satellite IDs in the first satellite list and the second satellite list are exactly the same.

[0187] In this case, the first time is either the end time of the first timer or the second time. The second time is the minimum value among the start service times associated with the second satellite list, or the start service time associated with a satellite in the second satellite list. There is no specific limitation on the specific satellite mentioned; please refer to the relevant content in the aforementioned case A, which will not be repeated here.

[0188] If the satellite IDs in the first satellite list and the second satellite list are exactly the same, then the arrival time of the first satellite in the first satellite list, as indicated by the first timer, is the same as the arrival time of the first satellite in the second satellite list (the second time). The terminal device detects satellites according to the first timer. No other satellites will arrive before the first timer expires. Therefore, the terminal device does not perform AS operation before the first time (the end time of the first timer), which avoids missing satellites in normal mode, saving power consumption and allowing for early satellite access. If the NAS message does not include the first timer, the terminal device detects satellites according to the second time, and does not perform AS operation before the second time.

[0189] Optionally, the NAS entity of the terminal device can send the first satellite list to the AS entity of the terminal device. The AS entity then determines whether all satellite IDs in the first and second satellite lists are identical. Alternatively, the AS entity of the terminal device can send the second satellite list to the NAS entity, which then determines whether all satellite IDs in the first and second satellite lists are identical and sends the determination result to the AS entity, which decides whether to stop the AS operation. Alternatively, the NAS entity can determine whether all satellite IDs in the first and second satellite lists are identical. If all satellite IDs in the first and second satellite lists are identical, the NAS entity further calculates a first time interval and instructs the AS entity whether the AS operation needs to be stopped.

[0190] In Embodiment 1, when the terminal device is configured with a first satellite list and a second satellite list, the terminal device does not perform AS operation before the first time; after the first time, it determines whether to execute the satellite access procedure based on the detected satellites. Since the terminal device does not perform AS operation before the first time, the power consumption of the terminal device can be minimized.

[0191] Optionally, upon determining the first time, the terminal device may check whether the satellite IDs in the first satellite list and the second satellite list are completely identical. If they are completely identical, the terminal device will not perform the AS operation before the end time of the first timer or the minimum value of the start service time associated with the second satellite list. If the satellite IDs in the first satellite list and the second satellite list are not completely identical, the first time can be determined according to situations A to B above, and the AS operation will not be performed before the first time.

[0192] Example 2

[0193] Please refer to Figure 6, which is a flowchart illustrating a second communication method provided in an embodiment of this application. Figure 6 describes the method from the perspective of interaction between the satellite, core network equipment, and terminal equipment.

[0194] S601, the core network device sends a NAS message, and the terminal device receives the NAS message from the core network device accordingly.

[0195] The NAS message may include a first timer, which indicates the waiting time for retrying the NAS process, or the first timer instructs the terminal device to continuously monitor satellites in the first satellite list before the first timer expires. For example, the first timer may be the "wait timer" mentioned above. In this embodiment, the first timer is associated with a first satellite, which is the first satellite among the satellites after the terminal device leaves the current satellite that can obtain the context of the terminal device, or the first satellite among the subsequent satellites that can obtain the context of the terminal device. Optionally, the first satellite's operating mode is normal mode, or the first satellite's operating mode is store-and-forward mode.

[0196] Since the first satellite associated with the first timer can obtain the context of the terminal device, there will be no satellite in normal mode while waiting for the NAS satellite. Even if a satellite in normal mode appears, it is configured to the terminal device via NAS messages. Therefore, the terminal device is in an idle state and does not need to perform AS operations before the end of the first timer, thereby reducing the power consumption of the terminal device. After the end of the first timer, the process of accessing the first satellite can be executed.

[0197] Alternatively, the NAS message may include a first satellite list, which is the first satellite among those satellites after the terminal device leaves the current satellite that can obtain the context of the terminal device. Optionally, the first satellite may operate in normal mode or in store-and-forward mode.

[0198] Since the first satellite in the satellite list configured by the NAS message can obtain the context of the terminal device, there will be no satellite in normal mode while waiting for the NAS satellite. Even if a satellite in normal mode appears, it is configured to the terminal device by the NAS message. In this case, when the terminal device is in an idle state, AS operation can be avoided before the end of the first timer, thereby reducing the power consumption of the terminal device. After the end of the first timer, the process of accessing the first satellite can be executed.

[0199] Optionally, the NAS message includes a first timer and a first satellite list. The first satellite associated with the first timer is the first satellite among the satellites after the terminal device leaves the current satellite that can obtain the context of the terminal device. The first satellite list includes the first satellite among the satellites after the terminal device leaves the current satellite that can obtain the context of the terminal device.

[0200] S602, Satellite transmits system messages; correspondingly, the terminal equipment receives system messages from the satellite.

[0201] The execution order of S602 and S601 is not restricted. For example, S602 can be executed before S601, after S601, or simultaneously with S601.

[0202] The system message includes a second satellite list, which can indicate subsequent satellites with non-continuous coverage. For details, please refer to the relevant content in the aforementioned S502, which will not be repeated here.

[0203] S603: The terminal device executes the process of accessing the first satellite based on the NAS message.

[0204] The terminal device uses the first satellite list configured in the NAS message as a reference. If the NAS message does not include the first timer, the terminal device will not perform AS operations before the first time. The first time is the minimum of at least one start service time corresponding to a satellite in the first satellite list, which the terminal device searches in the second satellite list for. After the first time, the process of accessing the first satellite can be executed.

[0205] Optionally, the NAS entity of the terminal device sends the first satellite list to the AS entity of the terminal device, and the AS entity determines the first time. Alternatively, the AS entity of the terminal device sends the second satellite list and the start service time associated with each satellite in the second satellite list to the NAS entity, and the NAS entity determines the first time and sends the first time to the AS entity.

[0206] If the core network equipment does not send a NAS message including the first satellite list, or if the core network does not indicate the first satellite list and / or the first timer, the terminal equipment detects satellites according to the normal discontinuous coverage principle.

[0207] In S603, “execute the procedure for accessing the first satellite” can be replaced with “start AS or execute AS operation”.

[0208] Example 3

[0209] Please refer to Figure 7, which is a flowchart illustrating a third communication method provided in an embodiment of this application. Figure 7 describes the method from the perspective of interaction between the satellite, core network equipment, and terminal equipment.

[0210] S701, the core network device sends a NAS message, and the terminal device receives the NAS message from the core network device accordingly.

[0211] The NAS message may include a first satellite list, which may instruct the terminal device to retry the NAS process or the satellites to receive data. Refer to the relevant content in S501 above, which will not be repeated here.

[0212] S702, Satellite transmits system messages; correspondingly, the terminal equipment receives system messages from the satellite.

[0213] The execution order of S702 and S701 is not restricted. For example, S702 can be executed before S701, after S701, or simultaneously with S701.

[0214] The system message includes a second satellite list that indicates subsequent satellites with non-contiguous coverage. If the satellite sending the system message is operating in normal mode, the second satellite list includes only satellites operating in normal mode. If the satellite sending the system message is operating in store-and-forward mode, the second satellite list includes satellites operating in normal mode and / or satellites operating in store-and-forward mode.

[0215] It should be understood that a satellite communication system may include satellites in normal mode and satellites in store-and-forward mode. Some terminal devices within the system support satellites in normal mode, while others support satellites in store-and-forward mode. If the satellite transmitting system messages is operating in normal mode, then the second satellite list only includes satellites operating in normal mode. This ensures that the terminal device can parse information from satellites in the second satellite list, allowing the terminal device to still normally reside on satellites in the second satellite list. Furthermore, including only satellites operating in normal mode in the second satellite list reduces the amount of information included in system messages, lowering air interface resource overhead. If the satellite transmitting system messages is operating in store-and-forward mode, then the second satellite list includes satellites operating in normal mode and / or satellites operating in store-and-forward mode, enabling the terminal device to obtain more satellite information and supporting rapid access for the terminal device.

[0216] S703. The terminal equipment executes the satellite access procedure based on system messages.

[0217] The terminal device obtains a second satellite list and detects satellites based on the start service time associated with each satellite in the second satellite list. If a satellite in the second satellite list is detected, the process of accessing that satellite can be executed.

[0218] Example 4

[0219] Please refer to Figure 8, which is a flowchart illustrating the fourth communication method provided in an embodiment of this application. Figure 8 describes the method from the perspective of the interaction between the OAM device and the core network device.

[0220] S801, OAM device sends first information.

[0221] For example, the OAM device sends first information to core network equipment (such as MME or AMF), and the core network equipment (such as MME or AMF) receives the first information from the OAM device. As another example, the OAM device sends first information to a base station / satellite, and the base station / satellite receives the first information from the OAM device. Figure 8 illustrates the example of an OAM device sending first information to a satellite and a core network device.

[0222] The first piece of information indicates the correspondence between ephemeris information and satellite identifiers.

[0223] Optionally, the first information may also be used to indicate the correspondence between geographic location information and ephemeris information, or the first information may also be used to indicate the correspondence between geographic location information and satellite identifier, or the first information may also be used to indicate the correspondence between geographic location information, ephemeris information, and satellite identifier. There are no restrictions on the specific geographic location; for example, the location information may be a TAC, cell ID, or base station ID.

[0224] Optionally, the correspondence between ephemeris information and satellite identifier, the correspondence between geographic location information and ephemeris information, the correspondence between geographic location information and satellite identifier, or the correspondence between geographic location information, ephemeris information, and satellite identifier can be pre-configured in core network equipment (such as MME or AMF), or pre-configured in base stations / satellites, or predefined by a protocol. In this case, OAM does not need to send the first information. Therefore, S801 is an optional step.

[0225] Considering that satellite IDs may not be globally unique, NAS messages and system messages may use different IDs to indicate the same satellite, leading to different meanings for the same satellite ID in the NAS message and system message, causing the terminal device to execute the procedure for accessing the wrong satellite. Therefore, in this embodiment, the OAM device can configure first information for the core network device and also for the satellite. This avoids the terminal device identifying the wrong satellite and thus prevents it from executing the procedure for accessing the wrong satellite.

[0226] The methods provided in this application are described above using satellites, core network equipment, and terminal equipment as examples. In this application, each embodiment can be implemented independently or in combination based on certain inherent connections; within each embodiment, different implementation methods can be implemented in combination or independently. To achieve the functions of the methods provided in the above-described embodiments, the satellite, core network equipment, and terminal equipment can each include hardware structures and / or software modules, implementing the above functions in the form of hardware structures, software modules, or a combination of hardware structures and software modules. Whether a particular function is implemented in the form of hardware structures, software modules, or a combination of hardware structures and software modules depends on the specific application and design constraints of the technical solution.

[0227] Based on the same inventive concept as the method embodiments, this application provides a communication device. The communication device used to implement the above method in the embodiments of this application is described below with reference to the accompanying drawings. The content above can be used in subsequent embodiments, and repeated content will not be repeated.

[0228] Figure 9 is a schematic block diagram of a communication device 900 provided in an embodiment of this application. This communication device 900 can correspondingly implement the functions or steps implemented by satellite, core network equipment, or terminal equipment in the various method embodiments described above. The communication device 900 may include modules or units that implement the methods described above; for example, the communication device 900 includes a processing unit 910 and a transceiver unit 920. Optionally, the communication device may further include a storage unit 930, which can be used to store instructions (code or program) and / or data. The storage unit may be, for example, a memory. The processing unit 910 and the transceiver unit 920 may be coupled to the storage unit. For example, the processing unit 910 can read instructions (code or program) and / or data from the storage unit to implement the corresponding method.

[0229] The processing unit 910 may be a processor or controller, such as a CPU, general-purpose processor, DSP, ASIC, FPGA, programmable logic device (PLD), or other programmable logic device, transistor logic device, hardware component, or any combination thereof. It can implement or execute various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this application. The processor may also be a combination that implements computing functions, such as including one or more microprocessor combinations, a combination of DSP and microprocessor, etc. When the communication device 900 is a system-on-a-chip, the processing unit 910 may be an FPGA, a dedicated ASIC, a SoC, a CPU, a network processor (NP), a DSP, an MCU, a PLD, or other integrated chip. The processing unit 910 may be a processor containing a system-on-a-chip.

[0230] The transceiver unit 920 is a transceiver, interface circuit, bus, pin, or other possible communication interface used to receive signals from other devices. For example, when the device is implemented as a chip, the transceiver unit 920 is an interface circuit for the chip to receive signals from other chips or devices, or an interface circuit for the chip to send signals to other chips or devices. For example, the interface circuit can be a code / data read / write interface circuit. This interface circuit can be used to receive code instructions (stored in memory, which can be read directly from memory or through other devices) and transmit them to the processing unit 910. As another example, the interface circuit can also be a signal transmission interface circuit between a communication processor and a transceiver. When the communication device 900 is a chip-type device or circuit, the transceiver unit 920 can be an input / output circuit and / or a communication interface; the processing unit 910 is an integrated processor, microprocessor, or integrated circuit.

[0231] When the communication device 900 is a module or unit within a device, the storage unit 930 can be a storage unit within the chip, such as a register or cache. For example, the storage unit 930 can also be a storage unit located outside the chip within a terminal device, satellite, or core network device, such as read-only memory (ROM) or other types of static storage devices capable of storing static information and instructions, such as random access memory (RAM), flash memory, or hard disk. The aforementioned units can be configured independently or partially or completely integrated. In one example, computer program instructions for executing the above embodiments can be stored in non-volatile memory, such as at least a portion of the storage unit 930 (e.g., one or more of ROM, flash memory, or hard disk). When the terminal device, core network device, or satellite is running, the corresponding computer program instructions may be partially or wholly loaded into a memory with a faster transmission speed than the processing unit 910, such as at least a portion of the aforementioned storage unit 930 (e.g., one or more of RAM, cache, or register), for the processing unit 910 to execute in order to implement the steps in the above method embodiments.

[0232] In one implementation, the communication device 900 can correspondingly implement the behavior and functions of the terminal device in the above method embodiments. The communication device 900 can be the terminal device itself, a component within the terminal device (e.g., a module, chip, or circuit), a part of a module, chip, or chipset in the terminal device used to execute the relevant method functions, or a software module in the terminal device capable of implementing the above communication method; there are no limitations. For details, please refer to the relevant content of the foregoing method embodiments, which will not be repeated here.

[0233] In Example 3-1, the transceiver unit 920 is used to receive NAS messages and system messages. The processing unit 910 is used to determine that, if the terminal device is in an idle state, no AS operation will be performed before a first time. The NAS message includes a first satellite list associated with a first timer, which indicates the waiting time for retrying the NAS process. The system message includes a second satellite list, where each satellite in the second satellite list is associated with a start service time. The first time is the minimum of the end time of the first timer and the second time. The second time is either the minimum of the start service times associated with the second satellite list, or the start service time associated with one satellite in the second satellite list.

[0234] As an optional design, the satellite identifiers in the first and second satellite lists may be the same or completely different.

[0235] As an optional design, NAS messages include a first timer.

[0236] As an optional design, the first timer ends later than the second time. The processing unit 910 is also used to determine whether, after the second time is reached, the process of accessing the first satellite is executed if the first satellite's operating mode is normal; or, after the second time is reached, the process of accessing the first satellite is not executed if the first satellite's operating mode is store-and-forward mode.

[0237] As an optional design, if the access procedure for the first satellite is not executed, no AS operation is performed before the third time. The third time is the minimum of the end time of the first timer and the fourth time. The fourth time is the minimum of the start service times of satellites in the second satellite list that are greater than the second time.

[0238] As an optional design, the second time is the minimum of the start-of-service times associated with satellites operating in normal mode in the second satellite list.

[0239] As an optional design, the first timer ends later than the second time, and the processing unit 910 determines that the satellite access process will be executed after the second time is reached.

[0240] As an optional design, the system message also includes information on the operating modes of the satellites in the second satellite list.

[0241] In Example 3-2, the transceiver unit 920 is used to receive NAS messages and system messages. The processing unit 910 is used to determine that, if the terminal device is in an idle state, no AS operation will be performed before a second time. The NAS message includes a first satellite list associated with a first timer, which indicates the waiting time for retrying the NAS process. The system message includes a second satellite list, where each satellite in the second satellite list is associated with a start service time, and the second satellite list contains the first satellite list. The second time is the minimum value among the start service times associated with the second satellite list, or the second time is the start service time associated with one satellite in the second satellite list.

[0242] As an optional design, the second time is the minimum of the start-of-service times associated with satellites operating in normal mode in the second satellite list.

[0243] As an optional design, the processing unit 910 is also configured to determine, upon reaching the fifth time, the procedure for accessing the satellite. The fifth time is the minimum of the second time and the sixth time, which is the minimum of the start-of-service time of the fourth satellite in the second satellite list, which is a satellite in the first satellite list.

[0244] As an optional design, the system message also includes information on the operating modes of the satellites in the second satellite list.

[0245] In Example 3-3, the transceiver unit 920 is used to receive NAS messages. The processing unit 910 is used to execute the access to the first satellite procedure based on the NAS message. The NAS message includes a first timer and / or a first satellite list. The first timer is used to indicate the waiting time for retrying the NAS procedure, and the first timer is associated with the first satellite, which is the first available satellite capable of obtaining the context of the terminal device. The first satellite list includes a first satellite, which is the first satellite among the satellites after the terminal device leaves the current satellite capable of obtaining the context of the terminal device.

[0246] In Examples 3-4, the transceiver unit 920 is used to receive system messages. The processing unit 910 is used to execute a procedure for accessing satellites in the second satellite list based on the system messages. The system messages include the second satellite list. Wherein, the satellite sending the system messages operates in normal mode, and the second satellite list only includes satellites operating in normal mode. Alternatively, the satellite sending the system messages operates in store-and-forward mode, and the second satellite list includes satellites operating in normal mode and / or satellites operating in store-and-forward mode.

[0247] In one implementation, the communication device 900 can correspondingly implement the behavior and functions of the satellite in the above method embodiments. The communication device 900 can be a satellite, a component within the satellite (e.g., a module, chip, or circuit), a part of a chip or chipset within the satellite used to perform the relevant method functions, or a software module within the satellite capable of implementing the above communication methods; there are no limitations. For details, please refer to the relevant content of the foregoing method embodiments, which will not be repeated here.

[0248] For example, transceiver unit 920 is used to transmit system messages, which include a second satellite list. The satellites transmitting the system messages operate in normal mode, and the second satellite list includes only satellites operating in normal mode. Alternatively, the satellites transmitting the system messages operate in store-and-forward mode, and the second satellite list includes satellites operating in normal mode and / or satellites operating in store-and-forward mode.

[0249] In one possible design, when the communication device 900 is a device (such as a satellite or terminal device) or a communication module within a device (such as a satellite or terminal device), the functionality of the processing unit 910 can be implemented by one or more processors. Specifically, the processor may include a modem chip, or a system-on-a-chip (SoC) chip or a SIP chip containing a modem core. The functionality of the transceiver unit 920 can be implemented by transceiver circuitry.

[0250] In one possible design, when the communication device 900 is a circuit or chip responsible for communication functions in a terminal device (or satellite), such as a modem chip or a system-on-a-chip (SoC) or SIP chip containing a modem core, the function of the processing unit 910 can be implemented by a circuit system in the aforementioned chip that includes one or more processors or processor cores. The function of the transceiver unit 920 can be implemented by the interface circuitry or data transceiver circuitry on the aforementioned chip.

[0251] In one possible design, when the communication device 900 is a terminal device (or satellite) or a communication and / or computing module within a terminal device (or satellite), the functionality of the processing unit 910 can be implemented by one or more processors. Specifically, the processor may include a DSP, or a system-on-a-chip (SoC) or SIP chip containing a DSP. Alternatively, the processor may include an ASIC, or a SoC or SIP chip containing an ASIC. The functionality of the transceiver unit 920 can be implemented by transceiver circuitry.

[0252] In one possible design, when the communication device 900 is a circuit or chip in a terminal device (or satellite) responsible for communication and / or computing functions, such as a DSP or a system-on-a-chip (SoC) or SIP chip containing a DSP, or an ASIC or a SoC or SIP chip containing an ASIC, the function of the processing unit 910 can be implemented by a circuit system in the aforementioned chip that includes one or more processors or processor cores. The function of the transceiver unit 920 can be implemented by interface circuits or data transceiver circuits on the aforementioned chip.

[0253] In one implementation, the communication device 900 can correspondingly implement the behavior and functions of the core network device in the above method embodiments. The communication device 900 can be a core network device, a component (e.g., a module, chip, or circuit) within the core network device, a part of a module, chip, or chipset in the core network device used to perform the relevant method functions, or a software module in the core network device capable of implementing the above communication method; there are no limitations. For details, please refer to the relevant content of the foregoing method embodiments, which will not be repeated here.

[0254] For example, transceiver unit 920 is used to send a NAS message, which includes a first timer and / or a first satellite list. The first timer is used to indicate the waiting time for retrying the NAS process, and the first timer is associated with a first satellite, which is the first available satellite capable of obtaining the context of the terminal device. The first satellite list includes a first satellite, which is the first satellite among the satellites after the terminal device leaves the current satellite capable of obtaining the context of the terminal device.

[0255] For example, the transceiver unit is used to receive first information, which is used to indicate the correspondence between ephemeris information and satellite identifiers.

[0256] As an optional design, the first information may also be used to indicate the correspondence between geographic location information and ephemeris information. Alternatively, the first information may also be used to indicate the correspondence between geographic location information and satellite identifiers. Or, the first information may also be used to indicate the correspondence between geographic location information, ephemeris information, and satellite identifiers.

[0257] In one possible design, when the communication device 900 is a circuit or chip responsible for communication functions in a core network device, such as a processing chip or a system-on-a-chip (SoC) or SIP chip containing a processing core, the function of the processing unit 910 can be implemented by a circuit system in the aforementioned chip that includes one or more processors or processor cores. The function of the transceiver unit 920 can be implemented by interface circuits or data transceiver circuits on the aforementioned chip.

[0258] In one possible design, when the communication device 900 is a circuit or chip in the core network equipment responsible for communication and / or computing functions, such as a DSP or a system-on-a-chip (SoC) or SIP chip containing a DSP, or an ASIC or a SoC or SIP chip containing an ASIC, the function of the processing unit 910 can be implemented by a circuit system in the aforementioned chip that includes one or more processors or processor cores. The function of the transceiver unit 920 can be implemented by the interface circuitry or data transceiver circuitry on the aforementioned chip.

[0259] In one implementation, the communication device 900 can correspondingly implement the behavior and functions of the OAM device in the above method embodiments. The communication device 900 can be an OAM device, a component within an OAM device (e.g., a module, chip, or circuit), a part of a module, chip, or chipset within an OAM device used to perform the relevant method functions, or a software module within an OAM device capable of implementing the above communication method; there are no limitations. For details, please refer to the relevant content of the foregoing method embodiments, which will not be repeated here.

[0260] For example, the transceiver unit 920 is used to transmit first information, which indicates the correspondence between ephemeris information and satellite identifiers.

[0261] As an optional design, the first information may also be used to indicate the correspondence between geographic location information and ephemeris information. Alternatively, the first information may also be used to indicate the correspondence between geographic location information and satellite identifiers. Or, the first information may also be used to indicate the correspondence between geographic location information, ephemeris information, and satellite identifiers.

[0262] In one possible design, when the communication device 900 is a circuit or chip responsible for communication functions in an OAM device, such as a processing chip or a system-on-a-chip (SoC) or SIP chip containing a processing core, the function of the processing unit 910 can be implemented by a circuit system in the aforementioned chip that includes one or more processors or processor cores. The function of the transceiver unit 920 can be implemented by interface circuitry or data transceiver circuitry on the aforementioned chip.

[0263] In one possible design, when the communication device 900 is a circuit or chip in an OAM device responsible for communication and / or computing functions, such as a DSP or a system-on-a-chip (SoC) or SIP chip containing a DSP, or an ASIC or a SoC or SIP chip containing an ASIC, the function of the processing unit 910 can be implemented by a circuit system in the aforementioned chip that includes one or more processors or processor cores. The function of the transceiver unit 920 can be implemented by interface circuits or data transceiver circuits on the aforementioned chip.

[0264] It is understood that the division of units in the aforementioned communication device 900 is merely a logical functional division. One function can correspond to one functional unit, or two or more functions can be integrated into one functional unit. In actual implementation, all or some units can be integrated into one physical entity, or distributed across different physical entities. Furthermore, the aforementioned functional units can be implemented in hardware, software, or a combination of both. Whether a function is executed 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 specific applications, but such implementation should not be considered beyond the scope of this application.

[0265] In one example, the functional unit in any of the above devices may be one or more integrated circuits configured to implement the above methods, such as: one or more ASICs, or one or more CPUs, one or more microcontroller units (MCUs), one or more DSPs, or one or more FPGAs, or a combination of at least two of these integrated circuit forms.

[0266] Figure 10 is a schematic block diagram of a communication device 1000 provided in an embodiment of this application. The communication device 1000 can be a terminal device, satellite, core network device, or OAM device as described in the above embodiments; or the communication device 1000 can be a module or unit within a terminal device, satellite, core network device, or OAM device as described in the above embodiments. For example, the communication device 1000 can be a chip (system) within a terminal device, satellite, core network device, or OAM device as described in the above embodiments. In this application embodiment, the chip system can be composed of chips or may include chips and other discrete devices. Specific functions can be found in the descriptions in the above method embodiments.

[0267] The communication device 1000 includes one or more processors 1001 for implementing or supporting the communication device 1000 in implementing the functions of the terminal device, satellite, core network device, or OAM device provided in the embodiments of this application. For details, please refer to the detailed description in the method examples, which will not be repeated here. The processor 1001 can implement certain control functions and may also be referred to as a processing unit, processing module, processor system, application processor, baseband processor, processor circuit, or processor core. Alternatively, the processing unit, processing module, processor system, application processor, baseband processor, processor circuit, or processor core are collectively referred to as a processor. The processor 1001 can be a general-purpose processor or a dedicated processor, etc. For example, it includes one or more combinations of: baseband processor, CPU, application processor, modem processor, GPU, image signal processor, DSP, video codec processor, controller, microprocessor unit (MPU), MCU, FPGA, ASIC, AI processor, or NPU. The baseband processor can be used to process communication protocols and communication data. The CPU can be used to control the communication device 1000 (e.g., network device or terminal device), execute software programs, and / or process data. Different processors can be independent devices or integrated into one or more processors, for example, integrated onto one or more application-specific integrated circuits.

[0268] In one design, processor 1001 may include program 1003 (sometimes also referred to as code or instructions), which can be executed on processor 1001 to cause communication device 1000 to perform the methods described in the embodiments below. In yet another possible design, communication device 1000 includes circuitry (not shown in FIG10) for implementing the functions of terminal devices, satellites, core network devices, or OAM devices in the above embodiments.

[0269] In one design, the communication device 1000 may include one or more memories 1002 storing a program 1004 (sometimes referred to as code or instructions), which can be run on the processor 1001 to cause the communication device 1000 to perform the methods described in the above method embodiments.

[0270] The aforementioned memory may include one or more of the following storage media: such as RAM, static random access memory (SRAM), dynamic random access memory (DRAM), cache, register, ROM, flash memory, hard disk, etc. In one example, the computer program instructions for executing the above embodiments may be stored in non-volatile memory. The aforementioned units may be set independently or partially or completely integrated. In one example, the computer program instructions for executing the above embodiments may be stored in non-volatile memory, such as at least a portion of the aforementioned memory 1002 (e.g., one or more of ROM, flash memory, or hard disk). When the terminal device or access network device is running, the corresponding computer program instructions may be partially or completely loaded into memory with a faster transmission speed than the processor 1001, such as at least a portion of the aforementioned memory 1002 (e.g., one or more of RAM, cache, or register), for the processor 1001 to execute in order to implement the steps in the above method embodiments.

[0271] In one design, the processor 1001 and / or memory 1002 may include AI modules 1007 and 1008, which are used to implement AI-related functions. The AI ​​modules can be implemented through software, hardware, or a combination of both. For example, the AI ​​modules may include RIC modules. For instance, the AI ​​modules may be near real-time RICs or non-real-time RICs.

[0272] In one possible design, the processor 1001 and / or memory 1002 may also store data. The processor and memory may be configured separately or integrated together.

[0273] In one possible design, the communication device 1000 may further include a transceiver 1005 and / or an antenna 1006. The processor 1001, sometimes referred to as a processing unit, controls the communication device 1000. The transceiver 1005, sometimes referred to as a transceiver unit, transceiver, transceiver circuit, or transceiver, is used to realize the transmission and reception functions of the communication device 1000 through the antenna 1006.

[0274] In one possible design, the communication device 1000 may further include one or more of the following components: a wireless communication module, an audio module, an external memory interface, internal memory, a universal serial bus (USB) interface, a power management module, an antenna, a speaker, a microphone, an input / output module, a sensor module, a motor, a camera, or a display screen, etc. It is understood that in some embodiments, the communication device 1000 may include more or fewer components, or some components may be integrated, or some components may be separated. These components may be implemented in hardware, software, or a combination of software and hardware.

[0275] This application also provides a communication system comprising at least one terminal device, multiple satellites, and core network equipment. The terminal device is used to implement the terminal device-related functions in the above-described communication method; the satellites are used to implement the network device-related functions in the above-described communication method; and the core network equipment is used to implement the network device-related functions in the above-described communication method. Optionally, the communication system further includes an OAM (Operational Access Management) device.

[0276] This application also provides a computer-readable storage medium including instructions that, when run on a computer, cause the methods executed by the terminal device, satellite, core network device, or OAM device in the above-described communication method to be executed.

[0277] This application also provides a computer program product, including computer program code, which, when executed, causes the methods executed by the terminal device, satellite, core network device, or OAM device in the above-described communication method to be executed.

[0278] This application provides a chip system including a processor and potentially a memory, for implementing the functions of terminal devices, satellites, core network devices, or OAM devices in the aforementioned communication methods. The chip system can be composed of chips or may include chips and other discrete components.

[0279] To achieve the functions of the communication devices shown in Figures 9 and 10, this application embodiment also provides a chip, including a processor, for supporting the communication device in implementing the functions involved in the terminal device, satellite, core network device, or OAM device in the above method embodiments. In one possible design, the chip is connected to a memory or the chip includes a memory for storing the necessary computer programs, instructions, and data of the communication device.

[0280] It should be understood that in the various embodiments of this application, the order of the above-mentioned processes does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0281] 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.

[0282] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0283] 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.

[0284] 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.

[0285] 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 essential contributing part of the technical solution of this application, 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, external hard drives, ROM, RAM, magnetic disks, or optical disks.

[0286] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A communication method characterized by comprising: The method is applied to a terminal device, and the method includes: Receive non-access stratum NAS messages and system messages. The NAS messages include a first satellite list, and the system messages include a second satellite list. The first satellite list is associated with a first timer, which is used to indicate the waiting time for retrying the NAS process. Each satellite in the second satellite list is associated with a service start time. When the terminal device is in an idle state, no access layer AS operation is performed before the first time. Wherein, the first time is the minimum value between the end time of the first timer and the second time, the second time is the minimum value among the start service times associated with the second satellite list, or the second time is the start service time associated with a satellite in the second satellite list.

2. The method of claim 1, wherein, The satellite identifiers in the first satellite list and the second satellite list may be the same or completely different.

3. The method of claim 1 or 2, wherein, The NAS message includes the first timer.

4. The method of any one of claims 1-3, wherein, The first timer ends later than the second time, and the method further includes: After the second time period is reached, if the first satellite is in normal operating mode, the procedure for accessing the first satellite is executed; or, After the second time is reached, if the first satellite is in store-and-forward mode, the process of accessing the first satellite is not executed.

5. The method of claim 4, wherein, Without executing the access procedure for the first satellite, no AS operation is performed before the third time, wherein the third time is the minimum of the end time of the first timer and the fourth time, and the fourth time is the minimum of the start service times of the satellites in the second satellite list that are greater than the second time.

6. The method of any one of claims 1-3, wherein, The second time is the minimum of the service start times associated with the satellites operating in normal mode in the second satellite list.

7. The method of claim 6, wherein, The first timer ends no later than the second time, and the method further includes: After reaching the first time, the satellite access process is executed.

8. The method of claim 6, wherein, The system message also includes information on the operating modes of the satellites in the second satellite list.

9. A communication method characterized by comprising: The method is applied to a terminal device, and the method includes: Receive non-access stratum NAS messages and system messages. The NAS messages include a first satellite list, and the system messages include a second satellite list. The first satellite list is associated with a first timer, which is used to indicate the waiting time for retrying the NAS process. Each satellite in the second satellite list is associated with a service start time. When the terminal device is in an idle state, no access layer AS operation is performed before the first time. The second satellite list includes the first satellite list, and the first time is determined based on the second time, which is either the minimum value among the start service times associated with the second satellite list, or the first time is the start service time associated with a satellite in the second satellite list.

10. The method of claim 9, wherein, The second time is the minimum of the service start times associated with the satellites operating in normal mode in the second satellite list.

11. The method of claim 10, wherein, The method further includes: After reaching the fifth time, the satellite access process is executed. The fifth time is the minimum of the second time and the sixth time. The sixth time is the minimum of the start service time of the fourth satellite in the second satellite list. The fourth satellite is a satellite in the first satellite list.

12. The method of claim 10, wherein, The system message also includes information on the operating modes of the satellites in the second satellite list.

13. A communications device, characterized by include: The transceiver unit is used to receive non-access stratum NAS messages and system messages. The NAS messages include a first satellite list, and the system messages include a second satellite list. The first satellite list is associated with a first timer, which is used to indicate the waiting time for retrying the NAS process. Each satellite in the second satellite list is associated with a service start time. The processing unit is configured to determine that, if the communication device is in an idle state, no access layer AS operation will be performed before a first time. Wherein, the first time is the minimum value between the end time of the first timer and the second time, the second time is the minimum value among the start service times associated with the second satellite list, or the second time is the start service time associated with a satellite in the second satellite list.

14. The apparatus of claim 13, wherein, The satellite identifiers in the first satellite list and the second satellite list may be the same or completely different.

15. The apparatus of claim 13 or 14, wherein, The NAS message includes the first timer.

16. The apparatus of any one of claims 13-15, wherein, The first timer ends later than the second time, and the method further includes: After the second time period is reached, if the first satellite is in normal operating mode, the procedure for accessing the first satellite is executed; or, After the second time is reached, if the first satellite is in store-and-forward mode, the process of accessing the first satellite is not executed.

17. The apparatus of claim 16, wherein, Without executing the access procedure for the first satellite, no AS operation is performed before the third time, wherein the third time is the minimum of the end time of the first timer and the fourth time, and the fourth time is the minimum of the start service times of the satellites in the second satellite list that are greater than the second time.

18. The apparatus of any one of claims 13-15, wherein, The second time is the minimum of the service start times associated with the satellites operating in normal mode in the second satellite list.

19. The apparatus of claim 18, wherein, The first timer ends no later than the second time, and the method further includes: After reaching the first time, the satellite access process is executed.

20. The apparatus of claim 18, wherein, The system message also includes information on the operating modes of the satellites in the second satellite list.

21. A communications device, characterized by include: The transceiver unit is used to receive non-access stratum NAS messages and system messages. The NAS messages include a first satellite list, and the system messages include a second satellite list. The first satellite list is associated with a first timer, which is used to indicate the waiting time for retrying the NAS process. Each satellite in the second satellite list is associated with a service start time. The processing unit is configured to determine that, if the communication device is in an idle state, no access layer AS operation will be performed before a first time. The second satellite list includes the first satellite list, and the first time is determined based on the second time, which is either the minimum value among the start service times associated with the second satellite list, or the first time is the start service time associated with a satellite in the second satellite list.

22. The apparatus of claim 21, wherein, The second time is the minimum of the service start times associated with the satellites operating in normal mode in the second satellite list.

23. The apparatus of claim 22, wherein, The method further includes: After reaching the fifth time, the satellite access process is executed. The fifth time is the minimum of the second time and the sixth time. The sixth time is the minimum of the start service time of the fourth satellite in the second satellite list. The fourth satellite is a satellite in the first satellite list.

24. The apparatus of claim 22, wherein, The system message also includes information on the operating modes of the satellites in the second satellite list.

25. A chip or chip system, characterized by The chip or chip system includes: At least one processor and an interface, the at least one processor being configured to call and execute instructions from the interface, such that when the at least one processor executes the instructions, the method as claimed in any one of claims 1-8 is executed, or the method as claimed in any one of claims 9-12 is executed.

26. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store a computer program or instructions that, when executed, cause the method as described in any one of claims 1-8 to be performed, or cause the method as described in any one of claims 9-12 to be performed.

27. A computer program product, characterised in that, The computer program product includes a computer program or instructions that, when executed, cause the method as described in any one of claims 1-8 to be performed, or cause the method as described in any one of claims 9-12 to be performed.

Images