Communication method, electronic equipment, communication system and readable storage medium

Abstract

The invention provides a communication method, electronic equipment, a communication system and a readable storage medium, which are beneficial to reducing paging monitoring power consumption of user equipment. The method comprises the following steps: when a first service link between a first satellite and UE is in a connection state, receiving a first system message from a first base station deployed on the first satellite, the first system message carrying time information that a first feeder link is in the connection state, the time information of the first feeder link in the connection state is used for indicating the moment or time period of the first satellite when the feeder link is in the connection state last time before the first service link starts to be in the connection state; and determining to monitor or neglect the first paging message of the first base station according to the time information that the first feeder link is in the connection state.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a communication method, electronic device, communication system, and readable storage medium. Background Technology

[0002] For on-board regeneration architecture of non-terrestrial network (NTN), in store-and-forward mode, when the core network has a paging message to send to the UE, the core network will send the same paging message to one or more satellites (including onboard MME / onboard base station). The UE will listen for paging messages sent by one or more satellites that arrive at the UE tracking area, which results in high power consumption of the UE. Summary of the Invention

[0003] This application provides a communication method, electronic device, communication system, and readable storage medium, which helps to reduce the paging and monitoring power consumption of user equipment.

[0004] In a first aspect, a communication method is provided, the method being applied to a user equipment (UE), the method comprising: when a first service link between a first satellite and the UE is in a connected state, receiving a first system message from a first base station deployed on the first satellite, the first system message carrying time information of a first feeder link being in a connected state, the time information of the first feeder link being in a connected state being used to indicate the time or time period of the most recent feeder link being in a connected state before the first service link began to be in a connected state; and determining, based on the time information of the first feeder link being in a connected state, to listen to or ignore a first paging message from the first base station.

[0005] The phrase "link is in a connected state" can also be described as "link is in an active state" or "link is in an available state." When the satellite's link is in a connected, active, or available state, data can be exchanged with the satellite via the link. Conversely, when the satellite's link is in a disconnected, invalid, or unavailable state, data cannot be exchanged with the satellite via the link.

[0006] According to the communication method provided in this application embodiment, for a non-terrestrial network NTN on-board regeneration architecture, when the first service link between the first satellite and the UE is in a connected state, the UE can receive a first system message from the first base station deployed on the first satellite. This first system message carries time information indicating the time or time period during which the first feeder link was in a connected state before the current first service link begins to be connected. Based on this time information, the UE determines whether to listen to or ignore the first paging message from the first base station. With this solution, even if the same paging message for the UE is sent to one or more satellites, the UE can determine when to listen to the paging message and ignore it at other times. Therefore, the UE will not repeatedly listen to the same paging message, thus saving the UE's power consumption.

[0007] In this embodiment, the first satellite uses store-and-forward mode.

[0008] In some embodiments of the first aspect, the time information of the first feeder link being in the connected state includes at least one of the following: the time when the first feeder link begins to be in the connected state, the duration of the first feeder link being in the connected state, and the time when the first feeder link ends to be in the connected state.

[0009] By using the time information of the first feeder link being in a connected state, the time or time period of the most recent feeder link being in a connected state before the current service link starts to be in a connected state can be determined. This allows us to determine whether the UE has experienced at least one service link connection after the most recent feeder link connection of the satellite and before the current service link connection of the satellite, and thus determine whether it is necessary for the UE to listen to paging messages.

[0010] It should be noted that, considering that the same satellite may send a paging message after its first arrival in the tracking area and may send the same paging message again after arriving in the tracking area again, the UE does not need to listen for paging messages sent by the same satellite after it arrives in the UE's tracking area again. In the first embodiment, if the UE has experienced at least one service link connection after the most recent feeder link of satellite 1 and before the current service link of satellite 1, the UE skips paging listening during the current service link connection.

[0011] It should also be noted that, considering that different satellites may send the same paging message after arriving in the tracking area, resulting in duplicate paging messages, the UE does not need to listen to the paging message sent by each satellite arriving in the UE's tracking area. In the second embodiment, the UE can determine to skip paging listening during the current service link connection period based on the time information of the most recent feeder link connection of the current satellite 2 and the time information of the most recent feeder link connection of the previous satellite 1.

[0012] In some embodiments of the first aspect, the time is represented as an absolute time, a first relative time, or a second relative time. The first relative time is indicated by an offset in system time (UTC), the offset being in seconds. The second relative time is indicated by an offset with reference to the start time of the satellite's downlink subframe in the current cell, the offset being the number of radio frames, the number of subframes, and / or seconds.

[0013] In some examples, the times when the first feeder link begins to be connected and when the first feeder link ends to be connected can be absolute times, such as xx day xx hour xx minute xx second, or xx month xx day xx hour xx minute xx second.

[0014] In other examples, the times when the first feeder link begins to be connected and when the first feeder link ends to be connected can be relative times, for example, indicated by an offset of system time (UTC) TimeOffsetUTC, which is an offset relative to the start time of the week (Monday 00:00:00), such as a value of xx seconds.

[0015] In some other examples, the time when the first feeder link begins to be connected and the time when the first feeder link ends to be connected can be a relative time, for example, an offset with reference to the satellite's downlink subframe start time (epoch time) in the current cell, where the offset can be the number of radio frames, the number of subframes, and / or seconds.

[0016] In some embodiments of the first aspect, determining whether to listen to or ignore the first paging message of the first base station based on the time information of the first feeder link being in a connected state includes any of the following methods:

[0017] Method 1: If, based on the time information of the first feeder link being in a connected state, it is determined that the UE did not detect the first satellite providing services to the cell coverage area where the UE is located through the service link during the first time period, then it is determined to listen to the first paging message of the first base station.

[0018] The first time period is after the most recent feeder link of the first satellite ended and was in a connected state, and before the first service link started to be in a connected state.

[0019] It should be noted that when a paging message from a ground-based MME is sent to a satellite, the UE does not need to perform paging listening every time that satellite enters the UE's tracking area and the service link is available. The UE can ignore repeated paging listening to that satellite.

[0020] Method 2: If, based on the time information of the first feeder link being in a connected state, it is determined that the UE detected that the first satellite provided service to the cell coverage area where the UE is located through the service link during the first time period, then it is determined to ignore the first paging message of the first base station.

[0021] In Method 2, the same paging message from the terrestrial core network is sent to multiple satellites. The UE does not need to perform paging listening every time a satellite reaches its tracking area and the service link is available. The UE can ignore repeated paging from certain satellites, thus saving power consumption.

[0022] In some embodiments of the first aspect, determining whether to listen to or ignore the first paging message of the first base station based on the time information of the first feeder link being in a connected state includes: determining whether to listen to or ignore the first paging message of the first base station based on the time information of the first feeder link being in a connected state and the time information of the second feeder link of the second satellite being in a connected state.

[0023] Specifically, before the first service link between the UE and the first satellite begins to be connected, the second service link between the UE and the second satellite is in a connected state; the time information of the second feeder link being in a connected state is used to indicate the time or time period when the second satellite was in a connected state most recently before the second service link began to be connected.

[0024] In some embodiments of the first aspect, determining whether to listen to or ignore the first paging message of the first base station based on the time information of the first feeder link being in a connected state and the time information of the second feeder link of the second satellite being in a connected state includes:

[0025] Method 1: If the time information of the first feeder link being in a connected state and the time information of the second feeder link being in a connected state do not overlap, determine that the first paging message of the first base station is being monitored; or,

[0026] Method 2: If the time information of the first feeder link being in a connected state coincides with the time information of the second feeder link being in a connected state, or if the time period of the second feeder link being in a connected state includes the time period of the first feeder link being in a connected state, then it is determined that the first paging message of the first base station is being monitored.

[0027] In this embodiment, considering that different satellites may send the same paging message after arriving in the tracking area, resulting in duplicate paging messages, the UE does not need to listen to the paging messages sent by each satellite arriving in the UE's tracking area. In the second embodiment, the UE can determine to skip paging listening during the current service link connection period based on the time information (time T2 or time period) of the most recent feeder link connection of the current satellite 2 and the time information (time T1 or time period) of the most recent feeder link connection of the previous satellite 1. The UE can ignore repeated paging from certain satellites, which can save the UE's power consumption.

[0028] For example, in this embodiment, when the service link of satellite 2 is in a connected state, if the time T2 of satellite 2 coincides with the time T1 of satellite 1, then the UE will ignore the paging message sent by satellite S2 during the time period when the service link of satellite 2 is in a connected state. The UE can ignore repeated paging messages from certain satellites, which can save the UE's power consumption.

[0029] For example, in this embodiment, when the service link of satellite 2 is in a connected state, if the T1 time period of the previous satellite 1 includes the T2 time period of the current satellite 2, then the UE ignores listening to the paging message sent by satellite S2 during the current service link connection period of satellite 2. The UE can ignore listening to repeated paging messages from certain satellites, which can save the UE's power consumption.

[0030] In some embodiments of the first aspect, the method further includes: when the first service link is in a connected state, receiving a second system message from the first base station, the second system message carrying a first indication message for indicating to stop paging; and determining, based on the first indication message, to ignore the first paging message that is listening to the first base station.

[0031] In some embodiments of the first aspect, the first instruction message is used to instruct paging to cease within the cell broadcasting the second system message.

[0032] With the above-described scheme in this application, the UE can ignore repeated paging of certain satellites according to instructions, which can save the UE's power consumption.

[0033] Secondly, embodiments of this application provide a communication method applied to a first base station deployed on a first satellite. The method includes: when the first service link of the first satellite is in a connected state, broadcasting a first system message, wherein the first system message carries time information of the first feeder link being in a connected state, and the time information of the first feeder link being in a connected state is used to indicate the time or time period when the first satellite was in a connected state most recently before the first service link began to be in a connected state.

[0034] According to the communication method provided in this application, for a non-terrestrial network NTN on-board regeneration architecture, when the first service link between the first satellite and the UE is in a connected state, the first base station deployed on the first satellite can broadcast a first system message. This first system message carries time information indicating the time or period during which the first feeder link was in a connected state before the first service link began to be connected. Thus, after receiving the system message, the UE can determine whether to listen to or ignore the first paging message from the first base station based on the time information of the first feeder link's connection status. With this solution, even if the same paging message for the UE is sent to one or more satellites, the UE can determine when to listen to the paging message and ignore it at other times. Therefore, the UE does not need to perform paging listening every time a satellite reaches its tracking area and the service link is available, thus saving the UE's power consumption.

[0035] In some embodiments of the second aspect, the time information of the first feeder link being in the connected state includes at least one of the following: the time when the first feeder link begins to be in the connected state, the duration of the first feeder link being in the connected state, and the time when the first feeder link ends to be in the connected state.

[0036] In some embodiments of the second aspect, the time is represented as an absolute time, a first relative time, or a second relative time. The first relative time is indicated by an offset in system time (UTC), the offset being in seconds. The second relative time is indicated by an offset with reference to the start time of the satellite's downlink subframe in the current cell, the offset being the number of radio frames, the number of subframes, and / or seconds.

[0037] In some embodiments of the second aspect, prior to the first service link of the first satellite being in a connected state, the method further includes: receiving a first paging message for paging a UE from a first mobility management entity (MME) when the first feeder link of the first satellite is in a connected state.

[0038] The second MME refers to the ground MME.

[0039] In some embodiments of the second aspect, the method further includes: determining whether to page or stop page the UE based on time information indicating that the first feeder link is in a connected state.

[0040] In some embodiments of the second aspect, determining whether to page or stop page the UE based on the time information of the first feeder link being in a connected state includes: if, based on the time information of the first feeder link being in a connected state, it is determined that no service was provided by the first satellite to the cell coverage area where the UE is located via the serving link during a first time period, then determining to send the first paging message; or, if, based on the time information of the first feeder link being in a connected state, it is determined that the first satellite provided service to the cell coverage area where the UE is located via the serving link during the first time period, then determining to stop page the UE. The first time period is defined as after the most recent connection of the first satellite's feeder link ended and before the first serving link began to be connected.

[0041] With the above-described solution in this application, the satellite does not need to page the UE every time it arrives at the UE's tracking area and the service link is available, and can notify the UE to ignore the listening paging, thus saving the UE's power consumption.

[0042] In some embodiments of the second aspect, determining whether to page or stop paging the UE based on the time information of the first feeder link being in a connected state includes: determining whether to page or stop paging the UE based on the time information of the first feeder link being in a connected state and the time information of the second feeder link of the second satellite being in a connected state. Wherein, the second service link between the second satellite and the UE is in a connected state before the first service link between the first satellite and the UE begins to be in a connected state; the time information of the second feeder link being in a connected state is the time or time period of the most recent feeder link being in a connected state before the second service link begins to be in a connected state.

[0043] In some embodiments of the second aspect, determining whether to paging or stop paging the UE based on the time information of the first feeder link being in a connected state and the time information of the second feeder link of the second satellite being in a connected state includes: determining to send the first paging message when there is no overlap between the time information of the first feeder link being in a connected state and the time information of the second feeder link being in a connected state; or determining to stop paging the UE when the time information of the first feeder link being in a connected state overlaps with the time information of the second feeder link being in a connected state, or when the time period of the second feeder link being in a connected state includes the time period of the first feeder link being in a connected state.

[0044] In some embodiments of the second aspect, when it is determined that the first paging message will be stopped, the method further includes: sending a second system message, the second system message carrying a first indication message for indicating that paging will be stopped.

[0045] In some embodiments of the second aspect, the first indication message is used to instruct paging to cease within the cell broadcasting the second system message. Thus, after receiving the second system message, the UE can ignore listening to paging messages according to the indication, thereby saving UE power consumption.

[0046] Thirdly, embodiments of this application provide a communication method applied to a user equipment (UE). The method includes: when the first service link between the UE and a first satellite is in a connected state, receiving a second system message from a first base station deployed on the first satellite, the second system message carrying first indication information for indicating to stop paging in a cell broadcasting the second system message; and ignoring paging messages from the first base station according to the first indication information.

[0047] The communication method provided in this application embodiment allows the UE to ignore paging messages based on the stop paging instruction from the first satellite, thus saving the UE's power consumption.

[0048] Fourthly, embodiments of this application provide a communication method applied to a first base station deployed on a first satellite. The method includes: when the first service link of the first satellite is in a connected state, determining whether to paging or stop paging a UE based on time information of the first feeder link being in a connected state, wherein the time information of the first feeder link being in a connected state is used to indicate the time or time period when the first service link of the first satellite was in a connected state most recently.

[0049] According to the communication method provided in this application, for a non-terrestrial network NTN on-board regeneration architecture, when the first service link between the first satellite and the UE is in a connected state, the first base station deployed on the first satellite can determine whether to page or stop page the UE based on the time information of the first feeder link being in a connected state (used to indicate the time or time period when the first satellite was in a connected state before the first service link started to be in a connected state). With this solution, even if the same paging message for the UE is sent to one or more satellites, the satellite can determine when to page the UE when necessary and stop paging the UE at other times. Therefore, multiple satellites will not page repeatedly, and the UE can skip paging listening, thus saving the UE's power consumption.

[0050] In some embodiments of the fourth aspect, the time information of the first feeder link being in the connected state includes at least one of the following: the time when the first feeder link begins to be in the connected state, the duration of the first feeder link being in the connected state, and the time when the first feeder link ends to be in the connected state.

[0051] In some embodiments of the fourth aspect, the time is represented as an absolute time, a first relative time, or a second relative time. The first relative time is indicated by an offset in system time (UTC), the offset being in seconds. The second relative time is indicated by an offset with reference to the start time of the satellite's downlink subframe in the current cell, the offset being the number of radio frames, the number of subframes, and / or seconds.

[0052] In some embodiments of the fourth aspect, the method further includes: broadcasting a second system message, the second system message carrying a first indication message for indicating that paging should be stopped, upon determining that paging of the UE should be stopped.

[0053] In some embodiments of the fourth aspect, the first instruction message is used to instruct paging to cease within the cell broadcasting the second system message.

[0054] The proposed solution allows paging to be stopped via system message instructions, and the UE can skip paging listening based on these instructions, thus saving UE power consumption.

[0055] In some embodiments of the fourth aspect, prior to the first service link of the first satellite being in a connected state, the method further includes: receiving the first paging message for paging the UE from the first mobility management entity (MME) when the first feeder link of the first satellite is in a connected state.

[0056] The first MME refers to the onboard MME deployed on the first satellite.

[0057] In some embodiments of the fourth aspect, determining whether to paging or stop paging the UE based on the time information of the first feeder link being in a connected state includes: determining to send the first paging message if, based on the time information of the first feeder link being in a connected state, it is determined that no service was provided by the first satellite to the cell coverage area where the UE is located via the serving link during a first time period; or determining to stop paging the UE if, based on the time information of the first feeder link being in a connected state, it is determined that the first satellite provided service to the cell coverage area where the UE is located via the serving link during the first time period. The first time period is defined as after the most recent connection of the first satellite's feeder link ended and before the first serving link began to be connected.

[0058] In some embodiments of the fourth aspect, determining whether to page or stop paging the UE based on the time information of the first feeder link being in a connected state includes: determining whether to page or stop paging the UE based on the time information of the first feeder link being in a connected state and the time information of the second feeder link of the second satellite being in a connected state. Wherein, the second service link between the second satellite and the UE is in a connected state before the first service link between the first satellite and the UE begins to be in a connected state; the time information of the second feeder link being in a connected state is the time or time period of the most recent feeder link being in a connected state before the second service link begins to be in a connected state.

[0059] In some embodiments of the fourth aspect, determining whether to paging or stop paging the UE based on the time information of the first feeder link being in a connected state and the time information of the second feeder link of the second satellite being in a connected state includes: determining to send the first paging message when there is no overlap between the time information of the first feeder link being in a connected state and the time information of the second feeder link being in a connected state; or determining to stop paging the UE when the time information of the first feeder link being in a connected state overlaps with the time information of the second feeder link being in a connected state, or when the time period of the second feeder link being in a connected state includes the time period of the first feeder link being in a connected state.

[0060] In some embodiments of the fourth aspect, the first paging message is received during a period in which the time information of the first feeder link being in a connected state overlaps with the time information of the second feeder link being in a connected state.

[0061] Fifthly, embodiments of this application provide a communication method applied to a user equipment (UE). The method includes: reporting to a first base station deployed on a first satellite information about the UE's ability to support store-and-forward mode; receiving a third system message containing paging configuration information of the first base station; and determining a paging monitoring strategy in store-and-forward mode based on the paging configuration information.

[0062] In some embodiments of the fifth aspect, the paging configuration information in the store-and-forward mode includes a paging period and / or a paging density; wherein the paging period is M subframes; and the paging density is M paging subframes in one radio frame, or Y paging subframes in X radio frames, where M, N, X, and Y are all positive integers.

[0063] In some embodiments of the fifth aspect, the method further includes: listening to paging messages in store-and-forward mode and / or listening to paging messages in normal mode.

[0064] The store-and-forward mode is used to represent the communication mode when the service link and the feeder link are not in a valid state at the same time, and the normal mode is used to represent the communication mode when both the service link and the feeder link are in a valid state.

[0065] In some embodiments of the fifth aspect, listening to paging messages in store-and-forward mode includes: calculating the timing position for listening to paging messages in store-and-forward mode; and listening to paging messages at the calculated timing position.

[0066] In some embodiments of the fifth aspect, the paging configuration information of the first base station includes first paging configuration information corresponding to the normal mode and second paging configuration information corresponding to the store-and-forward mode;

[0067] The step of determining the paging monitoring strategy in the store-and-forward mode based on the paging configuration information includes: if the first paging configuration information and the second paging configuration information are the same, determining to adopt a first paging monitoring strategy in the store-and-forward mode, wherein the first paging period and / or the first paging density adopted by the first paging monitoring strategy are determined according to the first paging configuration information; or, if the first paging configuration information and the second paging configuration information are different, determining to adopt a second paging monitoring strategy in the store-and-forward mode, wherein the second paging period and / or the second paging density adopted by the second paging monitoring strategy are determined according to the second paging configuration information.

[0068] In some embodiments of the fifth aspect, when switching from the normal mode to the store-and-forward mode, the method further includes: if the UE supports discontinuous DRX paging mode, the UE continues to listen to paging messages using a determined first paging listening strategy or a second paging strategy, and stops listening to paging messages after a certain number of paging cycles; or, if the UE supports extended discontinuous reception eDRX paging mode and a time window has been started, the UE continues to listen to paging messages during the paging timing within the remaining time of the time window using the determined first paging listening strategy or the second paging strategy; or, if the UE supports the eDRX paging mode but has not started a time window, the UE stops listening to paging messages.

[0069] Sixthly, embodiments of this application provide a communication method applied to a first base station deployed on a first satellite. The method includes: receiving information about a UE's ability to support store-and-forward mode; and broadcasting a third system message containing paging configuration information of the first base station. The paging configuration information of the first base station includes first paging configuration information corresponding to the normal mode and second paging configuration information corresponding to the store-and-forward mode.

[0070] In some embodiments of the sixth aspect, the paging configuration information in the store-and-forward mode includes a paging period and / or a paging density; wherein the paging period is M subframes; and the paging density is M paging subframes in one radio frame, or Y paging subframes in X radio frames, where M, N, X, and Y are all positive integers.

[0071] In some embodiments of the sixth aspect, the method further includes: sending information about the UE's ability to support store-and-forward mode to a second mobility management entity (MME) deployed on a first satellite.

[0072] In some embodiments of the sixth aspect, the method further includes: receiving a first paging message from a second MME, the first paging message carrying capability information of the UE supporting the store-and-forward mode; and, based on the capability information of the UE supporting the store-and-forward mode, sending the first paging message to the UE in store-and-forward mode and / or normal mode.

[0073] In a seventh aspect, an embodiment of this application provides a communication system, characterized in that the communication system includes a user equipment (UE) and a first satellite; the first satellite includes a first base station and a second mobility management entity (MME); the second MME is used to send a first paging message to the first base station for paging the UE.

[0074] The UE executes the method in any of the possible implementations of the first aspect above, and the first base station executes the method in any of the possible implementations of the second aspect above; or, the UE executes the method in any of the possible implementations of the third aspect above, and the first base station executes the method in any of the possible implementations of the fourth aspect above; or, the UE executes the method in any of the possible implementations of the fifth aspect above, and the first base station executes the method in any of the possible implementations of the sixth aspect above.

[0075] Eighthly, embodiments of this application provide a processor, including: an input circuit, an output circuit, and a processing circuit. The processing circuit is configured to receive signals through the input circuit and transmit signals through the output circuit, causing the processor to execute the method in any of the possible implementations of the first to sixth aspects described above.

[0076] In the specific implementation process, the processor can be a chip, the input circuit can be an input pin, the output circuit can be an output pin, and the processing circuit can be a transistor, gate circuit, flip-flop, and various 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 output to, for example, but not limited 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 the input circuit and the output circuit at different times. This application does not limit the specific implementation of the processor and various circuits.

[0077] A ninth aspect provides a processing apparatus including a processor and a memory. The processor is configured to read instructions stored in the memory and to receive signals via a receiver and transmit signals via a transmitter to execute the methods in any of the possible implementations of the first to sixth aspects described above.

[0078] Optionally, the processor may be one or more, and the memory may be one or more.

[0079] Optionally, the memory may be integrated with the processor, or the memory may be separated from the processor.

[0080] In the specific implementation process, the memory can be a non-transitory memory, such as read-only memory (ROM), which can be integrated with the processor on the same chip or set on different chips. This application does not limit the type of memory or the way the memory and processor are set.

[0081] It should be understood that the relevant data interaction process, such as sending instruction information, can be a process of outputting instruction information from the processor, and receiving capability information can be a process of the processor receiving input capability information. Specifically, the processed output data can be output to the transmitter, and the input data received by the processor can come from the receiver. Here, the transmitter and receiver can be collectively referred to as transceivers.

[0082] The processing device in the ninth aspect above can be a chip. The processor can be implemented in hardware or software. When implemented in hardware, the processor can be a logic circuit, integrated circuit, etc.; when implemented in software, the processor can be a general-purpose processor that reads software code stored in memory. The memory can be integrated into the processor or located outside the processor and exist independently.

[0083] In a tenth aspect, a computer program product is provided, the computer program product comprising: a computer program (also referred to as code or instructions), which, when the computer program is run, causes a computer to perform the method in any of the possible implementations of the first to sixth aspects described above.

[0084] Eleventhly, a computer-readable storage medium is provided that stores a computer program (also referred to as code or instructions) that, when run on a computer, causes the computer to perform the methods in any of the possible implementations of the first to sixth aspects described above. Attached Figure Description

[0085] Figure 1A A schematic diagram of a communication system provided in an embodiment of this application is shown;

[0086] Figure 1B A schematic diagram of an NTN communication system provided in an embodiment of this application is shown;

[0087] Figure 2A A schematic diagram of the NTN transparent forwarding architecture is shown;

[0088] Figure 2B A schematic diagram of an NTN on-board regeneration architecture is shown;

[0089] Figure 2C A schematic diagram of another NTN on-board regeneration architecture is shown;

[0090] Figure 3A This diagram illustrates a paging scenario under the NTN on-board regeneration architecture.

[0091] Figure 3B This diagram illustrates another paging scenario under the NTN on-board regeneration architecture.

[0092] Figure 4 A schematic diagram of the process for transmitting paging messages via a feeder link in store-and-forward mode, provided in the first embodiment, is shown.

[0093] Figure 5A This illustration shows a flowchart of transmitting paging messages in store-and-forward mode according to the first embodiment;

[0094] Figure 5B This illustrates another flowchart of transmitting paging messages in store-and-forward mode provided in the first embodiment;

[0095] Figure 5C A further schematic diagram of the process of transmitting paging messages in store-and-forward mode provided in the first embodiment is shown;

[0096] Figure 6A schematic diagram of a scenario for transmitting paging messages in store-and-forward mode provided in the first embodiment is shown;

[0097] Figure 7A The diagram illustrates the process of two satellites transmitting paging messages via feeder links in store-and-forward mode, as provided in the second embodiment.

[0098] Figure 7B This diagram illustrates a scenario where two satellites establish feeder links and service links respectively in store-and-forward mode.

[0099] Figure 8A A flowchart illustrating the transmission of paging messages via a service link in store-and-forward mode, as provided in the second embodiment, is given.

[0100] Figure 8B A schematic diagram of a scenario for transmitting paging messages in store-and-forward mode provided in the second embodiment is shown;

[0101] Figure 9A A schematic diagram of the process of a satellite transmitting paging messages through a service link in store-and-forward mode, provided in the third embodiment, is shown.

[0102] Figure 9B A schematic diagram of a scenario for transmitting paging messages in store-and-forward mode, provided in the third embodiment, is shown.

[0103] Figure 10A The diagram illustrates the process of two satellites transmitting paging messages via a service link in store-and-forward mode, as provided in the fourth embodiment.

[0104] Figure 10B A schematic diagram of a scenario for transmitting paging messages in store-and-forward mode provided in the fourth embodiment is shown;

[0105] Figure 11 This application provides a schematic diagram illustrating the reporting process and paging process for UE's store-and-forward capability information.

[0106] Figure 12A This illustration shows a paging process in mode switching scenarios provided by an embodiment of this application;

[0107] Figure 12B A schematic diagram of DRX paging modes and eDRX is shown;

[0108] Figure 13 A schematic diagram of a scenario for transmitting paging messages in store-and-forward mode provided in the fifth embodiment is shown;

[0109] Figure 14 This is a schematic block diagram of a communication device provided in an embodiment of this application;

[0110] Figure 15 This is a schematic block diagram of another communication device provided in the embodiments of this application;

[0111] Figure 16 This is a schematic block diagram of another communication device provided in the embodiments of this application. Detailed Implementation

[0112] Figure 1A This is a schematic diagram of the architecture of the communication system 100 used in an embodiment of this application. Figure 1A As shown, the communication system includes a radio access network (RAN) 101, wherein the RAN 101 includes at least one RAN node (e.g., Figure 1A 110a and 110b, collectively referred to as 110, may also include at least one terminal device (such as...). Figure 1A RAN 101, denoted as RAN 120a-120j, is collectively referred to as RAN 120. RAN 101 may also include other RAN nodes, such as wireless relay equipment and / or wireless backhaul equipment. Figure 1A (Not shown in the image). Terminal device 120 is wirelessly connected to RAN node 110. Terminal devices and RAN nodes can be interconnected via wired or wireless means. Communication system 100 may also include core network 102. RAN node 110 is connected to core network 102 wirelessly or via wired means. The core network equipment in core network 102 and RAN node 110 in RAN 101 can be independent physical devices, or they can be the same physical device integrating the logical functions of core network equipment and RAN node. Communication system 100 may also include Internet 103.

[0113] RAN 101 can be an evolved universal terrestrial radio access (E-UTRA) system, a new radio (NR) system, or a future radio access system as defined in the 3rd generation partnership project (3GPP). RAN 101 can also include two or more of the above-mentioned different radio access systems. RAN 101 can also be an open RAN (O-RAN).

[0114] RAN nodes, also known as radio access network equipment, RAN entities, or access nodes, are used to help terminal devices access communication systems wirelessly. In one application scenario, an RAN node can be a base station, an evolved NodeB (eNodeB), a transmission reception point (TRP), a next-generation NodeB (gNB) in 5G mobile communication systems, a next-generation base station in 6G mobile communication systems, or a base station in future mobile communication systems. RAN nodes can also be macro base stations (such as...) Figure 1A 110a in the text), can also be a micro base station or an indoor station (such as... Figure 1A 110b in the middle can also be a relay node or a donor node.

[0115] In another application scenario, multiple RAN nodes can collaborate to help terminal devices achieve wireless access, with different RAN nodes implementing different functions of the base station. For example, a RAN node can be a central unit (CU), a distributed unit (DU), or a radio unit (RU). Here, the CU performs the functions of the base station's Radio Resource Control (RRC) and Packet Data Convergence Protocol (PDCP), and can also perform the functions of the Service Data Adaptation Protocol (SDAP). The DU performs the functions of the base station's Radio Link Control (RANC) and Medium Access Control (MAC) layers, and can also perform some or all of the physical layer functions. For specific descriptions of these protocol layers, refer to the relevant 3GPP technical specifications. The RU can be used to implement radio frequency signal transmission and reception. The CU and DU can be two independent RAN nodes, or they can be integrated into the same RAN node, such as within a baseband unit (BBU). RUs can be included in radio frequency equipment, such as remote radio units (RRUs) or active antenna units (AAUs). CUs can be further divided into two types of RAN nodes: CU-control plane and CU-user plane.

[0116] In different systems, RAN nodes may have different names. For example, in an O-RAN system, a CU can be called an open CU (O-CU), a DU can be called an open DU (O-DU), and an RU can be called an open RU (O-RU). The RAN nodes in the embodiments of this application can be implemented through software modules, hardware modules, or a combination of software and hardware modules. For example, a RAN node can be a server loaded with the corresponding software modules. The embodiments of this application do not limit the specific technology or device form used in the RAN nodes. For ease of description, a base station is used as an example of a RAN node in the following description.

[0117] A terminal device is a device with wireless transceiver capabilities, capable of sending signals to or receiving signals from a base station. Terminal devices can also be referred to as terminals, user equipment (UE), mobile stations, mobile terminals, etc. They can be widely used in various scenarios, such as device-to-device (D2D), vehicle-to-everything (V2X) communication, machine-type communication (MTC), the Internet of Things (IoT), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grids, smart furniture, smart offices, smart wearables, smart transportation, and smart cities. Terminal devices can be mobile phones, tablets, computers with wireless transceiver capabilities, wearable devices, vehicles, airplanes, ships, robots, robotic arms, smart home devices, etc. The embodiments of this application do not limit the specific technologies or device forms used in the terminal devices.

[0118] Base stations and terminal equipment can be fixed or mobile. They can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; they can also be deployed on water; and they can be deployed on aircraft, balloons, and satellites. The embodiments of this application do not limit the application scenarios of the base stations and terminal equipment.

[0119] The roles of base stations and terminal devices can be relative, for example, Figure 1AThe helicopter or drone 120i can be configured as a mobile base station. For terminal devices 120j accessing the wireless access network 101 via 120i, 120i is a base station; however, for base station 110a, 120i is a terminal device, meaning that 110a and 120i communicate via a wireless air interface protocol. Of course, 110a and 120i can also communicate via a base station-to-base station interface protocol; in this case, 120i is also a base station relative to 110a. Therefore, both base stations and terminal devices can be collectively referred to as communication devices. Figure 1A The 110a and 110b in the text can be referred to as communication devices with base station functions. Figure 1A The 120a-120j in the text can be referred to as communication devices with terminal functions.

[0120] Communication between base stations and terminal devices, between base stations, and between terminal devices can be conducted using licensed spectrum, unlicensed spectrum, or both simultaneously. Communication can be conducted using spectrum below 6 GHz, spectrum above 6 GHz, or both simultaneously. The embodiments of this application do not limit the spectrum resources used for wireless communication.

[0121] In the embodiments of this application, the functions of the base station can be executed by modules (such as chips) within the base station, or by a control subsystem that includes base station functions. This control subsystem, including base station functions, can be a control center in the aforementioned application scenarios such as smart grids, industrial control, intelligent transportation, and smart cities. Similarly, the functions of the terminal device can be executed by modules (such as chips or modems) within the terminal device, or by a device that includes terminal device functions.

[0122] In this application, the base station sends downlink signals or downlink information to the terminal device, with the downlink information carried on the downlink channel; the terminal device sends uplink signals or uplink information to the base station, with the uplink information carried on the uplink channel. In order to communicate with the base station, the terminal device needs to establish a radio connection with a cell controlled by the base station. The cell with which the terminal device has established a radio connection is called the serving cell of the terminal device. When the terminal device communicates with this serving cell, it is also subject to interference from signals from neighboring cells.

[0123] It is understood that in the embodiments of this application, the physical downlink shared channel (PDSCH), physical downlink control channel (PDCCH), and physical uplink shared channel (PUSCH) are only examples of downlink data channels, downlink control channels, and uplink data channels, respectively. In different systems and different scenarios, data channels and control channels may have different names, and the embodiments of this application do not limit this.

[0124] Currently, the protocol defines three RRC states for terminal devices: RRC connected (RRC_CONNECTED) state, RRC idle (RRC-IDLE) state, and RRC inactive (RRC-INACTIVE) state.

[0125] The RRC connected state refers to the state a terminal device is in after completing a random access procedure but before releasing the RRC. An RRC connection exists between the terminal device and network equipment (e.g., access network equipment). In the RRC connected state, the terminal device can transmit data with the network equipment, such as downlink and / or uplink data transmission. Alternatively, the terminal device can also transmit terminal-specific data and / or control channels with the network equipment to transmit specific information or unicast information.

[0126] RRC idle state refers to the state of a terminal device when it is camped in a cell but has not yet performed random access. The terminal device typically enters the RRC idle state after powering on or after RRC release. In the RRC idle state, there is no RRC connection between the terminal device and network devices (e.g., the camped network device), the network device does not store the terminal device's context, and no connection has been established between the network device and the core network for that terminal device. If the terminal device needs to transition from the RRC idle state to the RRC connected state, it must initiate an RRC connection establishment process.

[0127] The RRC inactive state is a state defined to reduce air interface signaling, quickly restore radio connectivity, and quickly restore data services. The RRC inactive state is a state between the connected state and the idle state. The terminal device had previously entered the RRC connected state and then released the RRC connection with the network device, but the network device retained the terminal device's context. Furthermore, the connection established between the network device and the core network for this terminal device was not released; that is, the user plane and control plane bearers between the RAN and the core network (CN) are still maintained, i.e., a CN-NR connection exists.

[0128] Terminal devices in RRC idle state and RRC inactive state can initiate random access to network devices. For ease of explanation, the terminal device will be referred to as UE below.

[0129] Here's a simplified explanation of the paging process. When the Mobility Management Entity (MME) needs to send downlink data to a UE in idle mode, the MME sends a paging message to all base stations within all tracking areas (TAs) registered to the UE. This paging message carries the UE's tracking area list (TAL) information. Then, the base stations send paging messages to all cells belonging to that TAL. In other words, the base station paging the UE via the air interface. When a UE in idle mode receives the paging message, it will initiate random access.

[0130] Figure 1A The communication system shown can be either a terrestrial network (TN) or a non-terrestrial network (NTN) communication system. TN mainly refers to traditional terrestrial communication networks, while NTN covers all non-terrestrial communication methods, especially communication networks implemented through non-terrestrial transmission means such as satellites.

[0131] The communication method provided in this application is applied to an NTN communication system (or NTN network), which uses satellite communication to provide communication services to user equipment (UE).

[0132] refer to Figure 1B The NTN communication system comprises three parts: the user side, the space side, and the ground side. The user side consists of various UEs, including handheld terminals, portable station terminals, embedded terminals, vehicle-mounted terminals, shipborne terminals, and airborne terminals. The space side comprises a satellite network of multiple communication satellites, which act as communication relay stations, providing connectivity between the user side and the ground side. Based on their orbital altitude, communication satellites can be categorized as low-earth orbit (LEO) satellites, medium-earth orbit (MEO) satellites, geostationary orbit (GEO) satellites, and high-elliptical orbit (HEO) satellites. The ground side includes NTN gateway stations, satellite control centers, telemetry and tracking stations, an operational support network, and a core network. The NTN gateway station connects to the core network through base stations within the operational support network.

[0133] In an NTN communication system, a communication link is established between the UE and a communication satellite, and a communication link is established between the communication satellite and a gateway station. The UE then accesses the core network via the satellite network. For ease of explanation, the link between the communication satellite and the UE is called a service link, the link between the communication satellite and the gateway station is called a feeder link, and the link between communication satellites is called an inter-satellite link (ISL). A feeder link can also be referred to as a power supply link.

[0134] NTN communication systems can include NTN transparent forwarding architecture and NTN on-board regeneration architecture.

[0135] NTN Transparent Forwarding Architecture

[0136] Figure 2A A schematic diagram of the NTN transparent forwarding architecture is shown. (For example...) Figure 2A As shown, in the NTN transparent forwarding architecture, the communication satellite and the UE form a service link, and the communication satellite and the ground NTN gateway station (or gateway) form a feeder link. The ground NTN gateway station is connected to the ground base station, and the ground base station is connected to the core network. The ground base station and the NTN gateway station together constitute the RAN.

[0137] In the NTN transparent forwarding architecture, the UE communicates with the ground base station via the service link and feeder link of the communication satellite. The communication satellite provides radio frequency relay forwarding functionality, and the data stream forwarding process is transparent between the communication satellite and the ground NTN gateway station. Specifically, the communication satellite can directly forward downlink signaling / data received from the ground base station to the UE via the feeder link, and the communication satellite can also directly forward uplink signaling / data received from the UE to the ground base station via the service link.

[0138] It should be noted that in the NTN transparent forwarding architecture, both the service link and the feeder link are in a connected (active) state, and the data transmission and signaling processes are consistent with those of the terrestrial network.

[0139] NTN On-board Regenerative Architecture

[0140] Figure 2B A schematic diagram of an NTN on-board regeneration architecture is shown. (For example...) Figure 2B As shown, base station functionality is integrated onto the communication satellite. In this case, the base station is referred to as a satellite-based base station. The satellite-based base station and the NTN gateway station constitute the RAN. The link between the UE and the satellite-based base station is a service link, and the link between the satellite-based base station and the ground NTN gateway station / ground core network is a feeder link. Thus, the UE communicates with the ground core network based on the service link and feeder link of the satellite-based base station.

[0141] Figure 2C A schematic diagram of another NTN on-board regeneration architecture is shown. (e.g.) Figure 2C As shown, base station functions and some core network functions are integrated onto the communication satellite. For ease of explanation, the portion of the core network deployed on the space side is referred to as the spaceborne core network, and the other portion deployed on the ground side is referred to as the terrestrial core network. The spaceborne base station, the spaceborne core network, and the NTN gateway station constitute the RAN. A feeder link connects the spaceborne base station / spaceborne core network to the terrestrial NTN gateway station / terrestrial core network, and a service link connects the spaceborne base station / spaceborne core network to the UE. Thus, the UE communicates with the terrestrial core network based on the service link and feeder link of the spaceborne base station / spaceborne core network.

[0142] In this embodiment, the NTN on-board regeneration architecture can be applied to the Internet of Things (IoT) - NTN.

[0143] In some embodiments, the NTN on-board regeneration architecture uses a 4G network, the base station can be an eNB, and the core network element can be a mobility management entity (MME). The onboard base station is called an onboard eNB, the onboard core network is called an onboard MME, and the terrestrial core network is called a terrestrial MME.

[0144] In other embodiments, the NTN on-board regeneration architecture employs a 5G network, with base stations that can be gNBs and core network elements that can be access and mobility management functions (AMFs). The onboard base station is referred to as an onboard gNB, the onboard core network as an onboard AMF, and the terrestrial core network as a terrestrial AMF.

[0145] For ease of explanation, the following embodiments of this application use the example of a feeder link between the onboard MME / onboard eNB and the ground MME, and a service link between the onboard MME / onboard eNB and the UE, for illustrative purposes. It is understood that in actual use, the onboard eNB can be replaced by the onboard gNB, the onboard MME can be replaced by the onboard AMF, and the ground MME can be replaced by the ground AMF.

[0146] The communication method provided in this application can be applied to either of the two NTN on-board regeneration architectures described above. The following embodiments all use... Figure 2C The NTN communication system shown is used as an example for illustration.

[0147] It should be noted that in the NTN transparent forwarding architecture, both the serving link and the feeder link are in a connected (active) state. For paging from the ground MME, the idle-state UE listens for paging according to the regular paging timing cycle. Paging listening is also known as paging detection. However, in the NTN on-board regeneration architecture, as the communication satellite moves along its orbit, sometimes both the feeder link and the serving link are connected, sometimes the feeder link is connected but the serving link is disconnected, and sometimes the serving link is connected but the feeder link is disconnected. In the NTN on-board regeneration architecture, paging detection for idle-state UEs is more complex when dealing with paging from the onboard MME / onboard eNB.

[0148] For this type of NTN on-board regeneration architecture, the NTN communication system can switch between normal mode and store-and-forward mode to achieve paging communication between the UE and the ground MME. The paging communication process includes the ground MME sending the paging message to the onboard MME / onboard eNB, the onboard MME / onboard eNB issuing the paging message, and the UE listening for the paging message.

[0149] Normal mode

[0150] Figure 3A This diagram illustrates a paging scenario within an NTN on-board regeneration architecture. (Reference) Figure 3A In (a) and (b) of the NTN satellite regeneration architecture, both the service link and the feeder link are in a connected state. Under this condition, the NTN communication system can use the normal mode to realize communication between the UE and the ground MME.

[0151] like Figure 3A As shown in (a), in normal mode, the ground MME can send a paging message to the onboard MME / onboard eNB at any time when a paging message is generated (step a1), and the onboard MME / onboard eNB can send the paging message to the UE at any time (step a2). Figure 3A As shown in (b), in normal mode, the UE can send the paging response message to the onboard MME / onboard eNB at any time (step b1), and the onboard MME / onboard eNB can send the paging response message to the ground MME at any time (step b2).

[0152] The normal mode can also be called the default mode or the standard mode.

[0153] Store-and-forward mode

[0154] Figure 3B This diagram illustrates another paging scenario under the NTN on-board regeneration architecture. (Example:) Figure 3BAs shown, in the NTN on-board regeneration architecture, the service link and the feeder link are not simultaneously connected. For example, at time t1, the service link of communication satellite S1 is unavailable, but the feeder link is available; at time t2 (later than t1), the service link of communication satellite S1 is available, but the feeder link is unavailable. In this case, the NTN communication system can use a store-and-forward mode to realize paging communication between the UE and the ground MME.

[0155] refer to Figure 3B In store-and-forward mode, the process of transmitting paging messages in the NTN communication system includes the following steps:

[0156] Step c1: When the feeder link is connected, the onboard MME / onboard base station of satellite S1 can receive paging messages from the ground MME through the feeder link.

[0157] Step c2: If the service link is disconnected, the onboard MME / onboard base station of satellite S1 stores the paging message.

[0158] Step c3: As the communication satellite S1 moves around its orbit, once the service link is established, the onboard MME / onboard base station of satellite S1 can send the stored paging messages to the UE.

[0159] In some embodiments, when the ground MME needs to send a paging message and the feeder link is available, the ground MME sends the paging message to the satellite MME. The satellite MME stores the paging message and, when the service link is available, sends the paging message to the satellite base station, which then paging the UE.

[0160] In other embodiments, when the ground MME needs to send a paging message and the feeder link is available, the ground MME sends the paging message to the satellite MME, the satellite MME sends the paging message to the satellite base station, the satellite base station stores the paging message, and when the service link is available, the satellite MME sends the paging message to the satellite base station, and then the satellite base station pages the UE.

[0161] Similar to the transmission of paging messages, the transmission of paging response messages is as follows: When the serving link is available, the onboard MME / onboard base station can receive the paging response message from the UE through the serving link; if the serving link is not connected, the onboard MME / onboard base station stores the paging response message; as the communication satellite S1 moves around its orbit, when the feeder link is connected, the onboard MME / onboard base station can send the stored paging response message to the ground MME.

[0162] In some embodiments, when a serving link or feeder link is detected to switch from an active state (link available) to an inactive state (link unavailable), the NTN communication system can switch from normal mode to store-and-forward mode. When both a serving link and a feeder link are detected to be available, the NTN communication system can switch from store-and-forward mode to normal mode.

[0163] It should be noted that for the NTN on-board regeneration architecture, in store-and-forward mode, when the ground MME has a paging message to send to the UE, the ground MME will forward the paging message to the satellite's onboard MME. When the satellite reaches the UE's tracking area, the satellite's onboard MME will forward the paging message to the satellite's onboard base station, which will then page the UE. Correspondingly, the UE will listen for the paging message during the paging process.

[0164] The ground-based MME will send the same paging message to one or more satellites (onboard MME / onboard base station). The UE will listen for paging messages sent by each satellite that arrives in the tracking area, which will result in high power consumption of the UE.

[0165] This application provides a communication method that can avoid unnecessary paging eavesdropping by the UE in paging scenarios where the same paging message from the terrestrial core network is sent to one or more satellites.

[0166] In the embodiments of this application, in store-and-forward mode, the UE may adopt the following paging monitoring strategy to avoid unnecessary paging monitoring.

[0167] Strategy 1 (UE-side improvement): The UE determines whether to perform paging monitoring.

[0168] In some embodiments, a paging message from a ground-based MME is sent to a satellite, and the UE does not need to perform paging listening every time the satellite enters the UE's tracking area and the service link is available. The UE can ignore repeated paging listening to the satellite.

[0169] In other embodiments, the same paging message from the terrestrial core network is sent to multiple satellites, and the UE does not need to perform paging listening every time a satellite reaches the UE's tracking area and the service link is available. The UE can ignore repeated paging listening for certain satellites.

[0170] In this embodiment, the UE supports store-and-forward mode.

[0171] Strategy 2 (Satellite-side improvement): The satellite indicates that paging should be stopped (no paging messages should be sent), and the UE will skip paging listening according to this indication.

[0172] In some embodiments, paging messages from a ground-based MME to a UE are sent to a satellite that does not need to paging the UE every time it reaches the UE's tracking area and a service link is available. The satellite may choose not to perform repeated paging, and it may stop paging by instructing the UE to do so via a system message, which the UE can then use to skip paging snooping.

[0173] In other embodiments, the same paging message from the ground MME to the UE is sent to multiple satellites, which do not necessarily need to paging the UE every time they reach the UE's tracking area and a service link is available. Some of the multiple satellites may not need to perform repeated paging and can stop paging by instructing the UE to do so via a system message, which the UE can then use to skip paging sniffing.

[0174] The specific implementation of the communication method provided in the embodiments of this application will be described below through examples.

[0175] First Implementation Example (UE-side Improvement)

[0176] In this embodiment, considering that the same satellite may send a paging message after its first arrival in the tracking area and may send the same paging message again after arriving in the tracking area again, the UE does not need to listen for paging messages sent by the same satellite after it arrives in the UE's tracking area again. In the first embodiment, if the UE has experienced at least one service link connection after the most recent feeder link of satellite 1 and before the current service link of satellite 1, the UE skips paging listening during the current service link connection. The first embodiment will be described in detail below with reference to flowchart illustrations and scenario illustrations.

[0177] Figure 4 A schematic diagram of the process for transmitting paging messages via a feeder link in store-and-forward mode, provided in the first embodiment, is shown.

[0178] S401. When the ground MME needs to page the UE, the ground MME determines the satellites (including satellite 1) that are about to arrive at the UE's tracking area TA.

[0179] In this embodiment of the application, when the ground MME needs to page the UE, the ground MME determines the time information of each satellite that will arrive at the TA based on the ephemeris information and the tracking area TA information registered by the UE.

[0180] In this embodiment, the NTN network can broadcast system messages in each NTN cell, and these system messages can carry satellite ephemeris information. The ground-based MME within the NTN cell can receive the system messages and obtain the ephemeris information from them. The ephemeris information may include satellite orbit information, orbital parameters at a specific time and their rate of change, or the satellite position at a specific time and its rate of change.

[0181] The tracking area (TA) information registered by the UE can refer to the UE's tracking area list (TAL), which can be stored on the ground MME. The TAL includes one or more tracking areas (TAs) registered by the UE. Each TA corresponds to a tracking area identity (TAI).

[0182] The time information of each satellite that is about to arrive at the TA may include the time when satellite 1 arrives at the TA and the time when the feeder link of satellite 1 is in a connected state.

[0183] S402, the feeder link between the ground MME and satellite 1 is in a connected state, and satellite 1 includes an onboard MME / eNB.

[0184] S403, the ground MME sends a paging message for the UE and the time information of satellite 1 to satellite 1 via the feeder link.

[0185] In this embodiment of the application, the time information of satellite 1 includes the time when satellite 1 arrives at TA and the time when satellite 1 is in a connected state with the feeder link of ground MME.

[0186] S404. Satellite 1 receives and stores the paging message and the time information of Satellite 1.

[0187] When a feeder link is established between satellite S1 and the ground MME, satellite S1 receives paging messages from the ground MME and time information from satellite S1 through the feeder link.

[0188] In some embodiments, paging messages and satellite 1 time information are stored via the onboard MME.

[0189] In other embodiments, paging messages and satellite 1's time information are stored via an onboard eNB.

[0190] For example, when a feeder link is established between the ground MME and the satellite, the ground MME sends a paging message and the time information of satellite 1 to the satellite's onboard MME, and the satellite's onboard MME sends the paging message and the time information of satellite 1 to the satellite's onboard eNB.

[0191] As satellite S1 moves along its orbit, at some point, the feeder link will disconnect. For example... Figure 4 As shown, "×" indicates that the link is in an invalid state.

[0192] After the feeder link of satellite S1 terminates, the service link between satellite S1 and the UE will be established at least once as satellite S1 moves along its orbit. A paging message from the ground MME is sent to satellite S1, and the UE does not need to perform paging listening every time the satellite enters the UE's tracking area and the service link is available. To avoid performing paging listening every time satellite S1 enters the UE's tracking area and the service link is available, in the first embodiment of this application, the UE determines whether to perform paging listening based on the time information of the satellite's most recent feeder link being in a connected state. The specific implementation process is described below.

[0193] Figure 5A A schematic diagram of the process for transmitting paging messages via a service link in store-and-forward mode, provided in the first embodiment, is shown.

[0194] S501. When the service link of satellite 1 is in a connected state, the onboard eNB of satellite 1 broadcasts a system message through the service link. The system message includes the time information of the most recent feeder link of satellite 1 that was in a connected state before this service link.

[0195] When satellite 1 enters one or more TA areas registered by the UE, the service link between satellite 1 and the UE is in a connected state.

[0196] In some embodiments, the timing information of the feeder link being in a connected state includes the moment when it begins to be in a connected state.

[0197] In some embodiments, the timing information of the feeder link being in a connected state includes the duration of time since it began to be in a connected state.

[0198] In some embodiments, the timing information of the feeder link being in a connected state includes the moment when it begins to be connected and the duration of the connection.

[0199] In other embodiments, the timing information of the feeder link being in a connected state includes the moment when the connection ends.

[0200] In some other embodiments, the timing information of the feeder link being in a connected state includes the time when it begins to be in a connected state and the time when it ends to be in a connected state.

[0201] In some other embodiments, the time information for when the feeder link is in a connected state includes the connection time period.

[0202] S502 and Satellite 1's onboard eNB send paging messages within the cell range of the UE's tracking area (TA) via the service link.

[0203] In this embodiment, the UE receives system messages broadcast by the satellite's onboard eNB through the service link. The UE obtains the time information of the most recent feeder link of satellite 1 being in a connected state before this service link from the system message. The UE determines whether to perform paging monitoring based on the time information of the most recent feeder link being in a connected state.

[0204] S503, the UE skips paging monitoring during the current service link connection period based on the time information of the most recent connection of the feeder link of satellite 1.

[0205] The following describes a possible implementation method for the UE to skip paging monitoring based on the time information of the most recent feeder link being in a connected state.

[0206] Method 1

[0207] In this embodiment of the application, if the UE determines, based on the time information of the most recent feeder link being in a connected state, that the UE has not experienced a service link connection after the most recent feeder link of satellite 1 and before the current service link of satellite 1, then the UE listens for the paging message sent by satellite S1 during the paging time when the current service link is in a connected state.

[0208] like Figure 5B As shown in S503A, in this embodiment of the application, if the UE determines, based on the time information of the most recent feeder link being in a connected state, that the UE has experienced at least one service link connection after the most recent feeder link of satellite 1 and before the current service link of satellite 1, then the UE skips paging monitoring during the current service link connection.

[0209] Method 2

[0210] like Figure 5C As shown in S503B, in this embodiment of the application, the UE determines that there is no feeder link connection of satellite 1 before the current service link based on the time information of the most recent feeder link connection of satellite 1. Then, the UE skips paging listening during the current service link connection.

[0211] Method 3

[0212] In this embodiment, the UE determines that the most recent link established by satellite S1 before the establishment of this service link is a feeder link based on the time information of the most recent feeder link being in a connected state. Then, the UE listens for paging messages sent by satellite S1 during the paging time when the service link is in a connected state.

[0213] In this embodiment, the UE determines that the link established by satellite S1 before the establishment of this service link is a service link (non-feeder link) based on the time information of the most recent feeder link being in a connected state. Then, the UE ignores listening to the paging message sent by satellite S1 during the time period when the current service link is in a connected state.

[0214] Method 4

[0215] In this embodiment, the UE can determine whether to listen to the paging message sent by the satellite S1 based on the number of times the UE has established a service link with the satellite S1 after the feeder link of the satellite S1 has ended its connection state.

[0216] In this embodiment, the UE receives a system message from satellite S1, which carries information about the time when the feeder link of satellite S1 was in a connected state. This information may include the time when the feeder link of satellite S1 ended its connected state. In this case, the UE can count the number of times it established a service link with satellite S1 after the feeder link of satellite S1 ended its connected state.

[0217] For example, whenever the service link between the UE and satellite S1 is active, the UE increments the count C by 1. The initial value of the count C is 0. As satellite S1 moves along its orbit, when satellite S1 re-establishes the feeder link with the ground MME, the UE resets the count C to zero.

[0218] Scenario 1: If the UE determines, based on the time information of the most recent feeder link being in a connected state, that the number of times the UE has established a service link with satellite S1 after the feeder link of satellite S1 ended its connection state is 1, then the UE will listen for paging messages sent by satellite S1 during the paging time when the service link is in a connected state.

[0219] Scenario 2: If the UE determines, based on the time information of the most recent feeder link being in a connected state, that the number of times the UE has established a service link with satellite S1 after the feeder link of satellite S1 ended its connection state is greater than or equal to 2, then the UE will ignore the paging messages sent by satellite S1 during the time period when the service link is in a connected state.

[0220] Method 5

[0221] In this embodiment of the application, if the UE determines that the current service link connection is the first connection after the feeder link of satellite S1 has ended its connection state based on the time information of the most recent feeder link being in a connected state, then the UE listens for the paging message sent by satellite S1 during the paging time during the time period when the current service link is in a connected state.

[0222] In this embodiment, if the UE determines, based on the time information of the most recent feeder link being in a connected state, that the current service link connection is not the first connection after the feeder link of satellite S1 ended its connection state, then the UE will ignore paging messages sent by satellite S1 during the time period when the current service link is in a connected state. That is, the UE will skip paging listening during the time period when the current service link is in a connected state.

[0223] In the first embodiment, when the satellite S1 first connects after the feeder link of the satellite S1 has ended its connection state, the satellite S1 has already sent a paging message to the UE to page the UE. If the current service link connection is not the first time the satellite S1 is connected after the feeder link of the satellite S1 has ended its connection state, then the UE does not need to listen to the paging message sent by the satellite S1 during the time period when the current service link is connected. In other words, the UE can skip paging listening during the time period when the current service link is connected, thereby avoiding unnecessary paging listening and reducing UE power consumption.

[0224] The above, with reference to the accompanying drawings, illustrates the flowchart of the transmission of paging messages via the feeder link and service link in store-and-forward mode provided by the first embodiment. The improvements of the first embodiment on the UE side are described below with reference to the accompanying drawings.

[0225] like Figure 6 In the original scheme shown, after satellite 1 establishes a feeder link with the ground MME, the ground MME sends a paging message for paging the UE to satellite 1; after the feeder link switches from an active state to an inactive state, satellite 1 sends a paging message to the UE while the service link between satellite 1 and the UE is in a connected state, and the UE listens for the paging; when the service link between satellite 1 and the UE switches from an active state to an inactive state and is connected again, the UE continues to listen for the paging during the time period when the service link is in a connected state.

[0226] like Figure 6 The improved scheme shown in the diagram, after the feeder link switches from an active state to an inactive state, when the service link of satellite 1 is in a connected state, satellite 1 sends a paging message to the UE. The UE determines to perform paging listening based on the time information of the most recent feeder link being in a connected state, and listens for paging at the paging time. When the service link of satellite 1 switches from an active state to an inactive state and is connected again, the UE determines to skip paging listening based on the time information of the most recent feeder link being in a connected state, and ignores paging listening during the time period when the service link is in a connected state.

[0227] The communication method provided in the first embodiment of this application eliminates the need for the UE to perform paging and listening every time a satellite arrives at the UE's tracking area and the service link is available, thus saving the UE's power consumption.

[0228] Second Implementation (UE-side Improvement)

[0229] The first embodiment described above provides an improvement in the communication method for a single satellite, while the second embodiment provides an improvement in the communication method for two or more satellites. For ease of explanation, satellite 1 and satellite 2 are used as examples below.

[0230] In this embodiment, considering that different satellites may send the same paging message after arriving in the tracking area, resulting in duplicate paging messages, the UE does not need to listen to the paging message sent by each satellite arriving in the UE's tracking area. In the second embodiment, the UE can determine to skip paging listening during the current service link connection period based on the time information of the most recent feeder link connection of the current satellite 2 and the time information of the most recent feeder link connection of the previous satellite 1. The second embodiment will be described in detail below with reference to the flowchart and scenario diagram.

[0231] Figure 7A The diagram illustrates the process of two satellites transmitting paging messages via feeder links in store-and-forward mode, as provided in the second embodiment.

[0232] S701 When the ground MME needs to page the UE, the ground MME determines the satellites (including satellite 1 and satellite 2) that are about to arrive at the UE's tracking area TA.

[0233] In this embodiment of the application, when the ground MME needs to page the UE, the ground MME determines the time information of each satellite that will arrive at the TA based on the ephemeris information and the tracking area TA information registered by the UE.

[0234] The time information of each satellite that is about to arrive at the TA can include the time when satellite 1 arrives at the TA and the time information when satellite 1's feeder link is in a connected state (connected state during time period T1), as well as the time when satellite 2 arrives at the TA and the time information when satellite 2's feeder link is in a connected state (connected state during time period T2).

[0235] S702. When both Satellite 1 (including the onboard MME / eNB) and Satellite 2 (including the onboard MME / eNB) are in the feeder link connection state, Satellite 1 receives paging message 1 from the ground MME and the time information of Satellite 1, and Satellite 2 receives paging message 1 from the ground MME and the time information of Satellite 2.

[0236] In this embodiment, the time information of satellite 1 includes the time when satellite 1 arrives at the TA and the time when satellite 1 is currently connected to the ground MME via a feeder link. The time information of satellite 2 includes the time when satellite 2 arrives at the TA and the time when satellite 2 is currently connected to the ground MME via a feeder link.

[0237] S703, Satellite 1 stores the time information of Satellite 1.

[0238] S704, Satellite 2 stores the time information of Satellite 2.

[0239] Figure 7B This diagram illustrates a scenario where two satellites establish feeder links and service links respectively in store-and-forward mode.

[0240] like Figure 7B As shown in (a), as satellite S1 and satellite S2 move along their respective orbits, at a certain moment, the feeder links between satellite S1 and the ground MME, and between satellite S2 and the ground MME, are both in a connected state. At this time, the feeder links are in a connected state, while the service links are in a disconnected state. Under these circumstances, paging message 1 from the ground MME can be received by satellites 1 and 2 respectively.

[0241] like Figure 7B As shown in (b), as satellite S1 moves along orbit 1, the service link between satellite S1 and the UE is in a connected state. When the service link of satellite S1 is in a connected state, satellite S1 can send paging message 1 through the service link.

[0242] like Figure 7B As shown in (c), as satellite S2 moves along orbit 2, the service link between satellite S2 and the UE is in a connected state. When the service link of satellite S2 is in a connected state, satellite S2 can send paging message 1 through the service link.

[0243] In other words, for the same paging message 1, satellite 1 will send paging message 1 when satellite 1 reaches the UE's tracking area and the service link 1 between the satellite and the UE is connected; similarly, satellite 2 will send paging message 1 when satellite 2 reaches the UE's tracking area and the service link 2 between the satellite and the UE is connected. Consequently, the UE will listen for paging message 1 sent by satellite 1 when service link 1 is connected, and the UE will also listen for paging message 1 sent by satellite 2 when service link 2 is connected. This scenario presents the problem of the UE repeatedly listening for the same paging message.

[0244] A paging message from the ground MME is sent to satellites 1 and 2. The UE does not need to listen to paging messages from every satellite reaching its tracking area. To avoid satellite 1 listening to paging messages from every satellite reaching the UE's tracking area, in the second embodiment of this application, the UE determines whether to perform paging listening based on the time information of the most recent feeder link connection status of satellite 1 and satellite 2. The specific implementation process is described below.

[0245] Figure 8A A flowchart illustrating the transmission of paging messages via a service link in store-and-forward mode, as provided in the second embodiment, is given.

[0246] It should be noted that both Satellite 1 and Satellite 2 received Paging Message 1 (e.g., Figure 7A As shown), then, satellite 1 first arrives at one or more TA areas registered by the UE, and then satellite 2 arrives at one or more TA areas registered by the UE.

[0247] S801. When the service link between satellite 1 and UE is in a connected state (available state or effective state), the onboard eNB of satellite 1 broadcasts a system message through the service link. The system message includes the time information (time period T1) of the most recent feeder link of satellite 1 in a connected state before this service link.

[0248] S802, the satellite-borne eNB of satellite 1 sends paging message 1 within the cell range of the UE's tracking area (TA) via the service link.

[0249] S803, the UE performs paging listening during this service link connection and stores the time period T1 if paging message 1 is detected.

[0250] S804. When the service link between satellite 2 and UE is in a connected state, the onboard eNB of satellite 2 broadcasts a system message through the service link. The system message includes the time information (time period T2) of the most recent feeder link of satellite 2 in a connected state before this service link.

[0251] The onboard eNB of S805 and Satellite 2 sends paging message 1 within the cell range of the UE's tracking area (TA) via the service link.

[0252] S806. Based on the time information of the most recent feeder link connection of satellite 1 and the most recent feeder link connection of satellite 2, the UE ignores the paging message 1 sent by satellite 2 during the current service link connection period.

[0253] In this embodiment, the UE determines whether to perform paging monitoring based on the time information of the most recent feeder link connection of satellite 1 and the most recent feeder link connection of satellite 2.

[0254] The following describes the possible implementation methods for the UE to determine whether to perform paging monitoring.

[0255] In this embodiment, when the satellite's service link is connected, the UE can obtain the time information of the most recent feeder link connection before the current service link from the satellite. When service links between multiple satellites and the UE are available, the UE can obtain the time information of the most recent feeder link connection of satellite (satellite 2) (time period T2) and the time information of the most recent feeder link connection of the previous satellite (satellite 1) (time period T1). The UE compares the time period T1 and the time period T2 to determine whether to listen for paging message 1 sent by satellite S2.

[0256] Scenario 1: Time period T1 and time period T2 overlap.

[0257] In this embodiment of the application, when the service link of satellite 2 is in a connected state, if the T2 time period of satellite 2 coincides with the T1 time period of satellite 1, then the UE ignores the paging message 1 sent by satellite S2 during the time period when the service link of satellite 2 is in a connected state.

[0258] Scenario 2: Time period T1 includes time period T2.

[0259] In this embodiment of the application, when the service link of satellite 2 is in a connected state, if the T1 time period of the previous satellite 1 includes the T2 time period of the current satellite 2, then the UE ignores the paging message 1 sent by the listening satellite S2 during the current service link connection of satellite 2.

[0260] The above, with reference to the accompanying drawings, illustrates the flowchart of the second embodiment for transmitting paging messages via the feeder link and service link in store-and-forward mode. The improvements of the second embodiment on the UE side are described below with reference to the accompanying drawings.

[0261] like Figure 8BIn the original scheme shown, when the ground MME establishes feeder links with both satellite S1 and satellite S2, the ground MME sends paging message 1 to the onboard MMEs of both satellite S1 and S2. As satellite S1 moves along orbit 1, when satellite S1 reaches the TA area registered by the UE and the service link is available, satellite S1 sends paging message 1 to page the UE, and the UE listens to the paging message sent by satellite S1. As satellite S2 moves along orbit 2, when satellite S2 reaches the TA area registered by the UE and the service link is available, satellite S2 sends paging message 1 to page the UE, and the UE still listens to the paging message sent by satellite S1.

[0262] like Figure 8B In the improved scheme shown in this embodiment, the UE completes the listening for paging messages based on the previous satellite (Satellite 1). When the current satellite (Satellite 2) arrives at the tracking area TA registered by the UE, if the time information of the most recent feeder link being in a connected state of Satellite 2 coincides with the time information of the most recent feeder link being in a connected state of Satellite 1, or the reachability time period of the most recent feeder link of Satellite 1 includes the reachability time period of the most recent feeder link of Satellite 2, then the UE skips listening to the paging messages sent by the current satellite (Satellite 2).

[0263] The communication method provided in the second embodiment of this application allows the same paging message from the ground core network to be sent to multiple satellites. The UE does not need to perform paging listening when each satellite arrives at the UE's tracking area and the service link is available, thus saving the UE's power consumption.

[0264] Third Embodiment (Satellite-Side Improvement)

[0265] In the third embodiment, the satellite instructs the UE to stop paging (not send paging messages), and the UE skips paging listening according to the instruction.

[0266] When a feeder link is established between satellite S1 and the ground MME, satellite S1 receives paging message 1 from the ground MME via the feeder link. After the feeder link of satellite S1 terminates, the service link between satellite S1 and the UE will be established one or more times as satellite S1 moves along its orbit. In the third embodiment of this application, a paging message from the ground MME is sent to satellite 1, which does not need to perform paging every time it reaches the tracking area of ​​the UE and the service link is available.

[0267] Figure 9A A schematic diagram of the process of a satellite transmitting paging messages through a service link in store-and-forward mode, provided in the third embodiment, is shown. Figure 9A The steps are as described above. Figure 4The process is executed after satellite 1 stores its time information. This time information includes the arrival time at the TA and the time the feeder link is in a connected state.

[0268] The service link between S901, Satellite 1 and UE is in a connected state.

[0269] S902. Satellite 1 (onboard MME / onboard eNB) determines, based on the time information of the most recent feeder link connection before the current service link, that if Satellite 1 and UE have established at least one service link connection after the most recent feeder link connection and before the current service link connection, then Satellite 1 (onboard MME / onboard eNB) will stop paging during the current service link connection.

[0270] In the third embodiment of this application, after the ground MME establishes a feeder link with satellite 1 and satellite 1 receives a paging message, when the service link between satellite 1 and UE is in a connected state, satellite 1 can determine to stop paging, that is, not send a paging message, based on the time information of the most recent feeder link of satellite 1 being in a connected state.

[0271] In some embodiments, if Satellite 1 determines, based on the time information of the most recent feeder link being in a connected state, that Satellite 1 has experienced at least one service link connection after the most recent feeder link and before the current service link of Satellite 1, then Satellite 1 stops paging during the current service link connection.

[0272] In other embodiments, if Satellite 1 determines that it did not have a feeder link connection before the current service link based on the time information of the most recent feeder link being in a connected state, then Satellite 1 will stop paging during the current service link connection period.

[0273] In some other embodiments, satellite 1 determines, based on the time information of the most recent feeder link being in a connected state, that the link most recently established by satellite S1 before establishing this service link is a service link (non-feeder link), and then satellite 1 stops paging during the connection of this service link.

[0274] In some other embodiments, if satellite 1 determines, based on the time information of the most recent feeder link being in a connected state, that the number of times satellite S1 and UE have established a service link after satellite S1's feeder link ended its connection state is greater than or equal to 2, then satellite 1 will stop paging during the current service link connection period.

[0275] In some other embodiments, if satellite 1 determines, based on the time information of the most recent feeder link being in a connected state, that the current service link connection is not the first connection after satellite S1's feeder link has ended its connection state, then satellite 1 stops paging during the current service link connection period.

[0276] It should be noted that the satellite side determines the possible implementation of stopping paging based on the time information of the most recent feeder link being in a connected state, similar to the UE side determining the possible implementation of skipping paging monitoring based on the time information of the most recent feeder link being in a connected state. This will not be elaborated further here.

[0277] S903 and Satellite 1 broadcast system messages via the service link. These system messages carry an instruction to stop paging and the UE's identifier.

[0278] S904. The UE receives the system message and, as instructed, skips paging listening during this service link connection.

[0279] In this embodiment, satellite S1 broadcasts a system message during the time the service link is in a connected state. This system message includes a "stop paging" instruction. Accordingly, the UE receives the system message broadcast by satellite S1 and skips paging listening according to the "stop paging" instruction.

[0280] With the solution proposed in this application, the UE can skip paging listening during the time period when the service link is in a connected state, thereby avoiding unnecessary paging listening and reducing UE power consumption.

[0281] The above, with reference to the accompanying drawings, illustrates the flowchart of the transmission of paging messages via the feeder link and service link in store-and-forward mode according to the third embodiment. The improvements of the third embodiment on the satellite side are described below with reference to the accompanying drawings.

[0282] like Figure 9B In the original scheme shown, after satellite 1 establishes a feeder link with the ground MME, the ground MME sends a paging message for paging the UE to satellite 1. After the feeder link switches from an active state to an inactive state, satellite 1 sends a paging message to the UE while the service link of satellite 1 is connected, and the UE listens for the paging. After the service link of satellite 1 switches from an active state to an inactive state, satellite 1 sends a paging message to the UE again when the service link is connected, and the UE continues to listen for the paging during the time period when the service link is connected.

[0283] like Figure 9BThe improved scheme shown describes a process where, after the feeder link switches from an active to an inactive state, when the service link of satellite 1 is in a connected state, satellite 1 determines to send a paging message to the UE based on the time information of the most recent feeder link being in a connected state, and the UE listens for paging during the paging period. After the service link of satellite 1 switches from an active to an inactive state, when satellite 1 is in a connected state again, satellite 1 determines to stop paging the UE based on the time information of the most recent feeder link being in a connected state, and instructs the UE to stop paging. The UE ignores listening for paging during the time period when the service link is in a connected state.

[0284] With the above solution, the satellite does not need to page the UE every time it arrives at the UE's tracking area and the service link is available, and can notify the UE to ignore the listening paging, thus saving the UE's power consumption.

[0285] With the communication method provided in the third embodiment of this application, since satellite S1 has already sent paging message 1 to UE during the first connection after the feeder link of satellite S1 has ended its connection state, if the current service link connection is not the first connection after the feeder link of satellite S1 has ended its connection state, then satellite S1 does not need to send paging message 1 during the time period when the current service link is in the connection state, thus avoiding unnecessary paging power consumption on the satellite side; of course, the UE also does not need to listen for paging again during the time period when the current service link is in the connection state. That is to say, the UE can skip paging listening during the time period when the current service link is in the connection state, thereby avoiding unnecessary paging listening and reducing UE power consumption.

[0286] Fourth Embodiment (Satellite-Side Improvement)

[0287] The third embodiment described above provides a satellite-side improvement in the communication method for a single satellite, while the fourth embodiment provides a satellite-side improvement in the communication method for two or more satellites. For ease of explanation, the following description will still use two satellites, Satellite 1 and Satellite 2, as examples.

[0288] In this embodiment, considering that different satellites send the same paging message after arriving in the tracking area, the UE needs to listen to the paging message sent by each satellite arriving in the UE's tracking area. In the fourth embodiment, the satellite can determine to stop paging during the current service link connection period based on the time information of the most recent feeder link connection of the current satellite 2 and the time information of the most recent feeder link connection of the previous satellite 1. The second embodiment will be described in detail below with reference to the flowchart and scenario diagram.

[0289] Figure 10AThe diagram illustrates the process of two satellites transmitting paging messages via a service link in store-and-forward mode, as provided in the fourth embodiment. It should be noted that both satellite 1 and satellite 2 receive paging message 1 (e.g., ...). Figure 7A As shown), then, satellite 1 first arrives at one or more TA areas registered by the UE, and then satellite 2 arrives at one or more TA areas registered by the UE.

[0290] S1001, Satellite 1 and UE's service link are in a connected state.

[0291] S1002, Satellite 2 and UE's service link are in a connected state.

[0292] As satellites S1 and S2 operate along their respective orbits, at a certain moment, the feeder links between satellite S1 and the ground MME, and between satellite S2 and the ground MME, are both connected. In this situation, paging message 1 from the ground MME can be received by both satellites. For the same paging message 1, satellite 1 will send paging message 1 when it reaches the UE's tracking area and the service link between it and the UE is connected; similarly, satellite 2 will send paging message 1 when it reaches the UE's tracking area and the service link between it and the UE is connected. Correspondingly, the UE will listen for paging message 1 sent by satellite 1 when service link 1 is connected, and the UE will also listen for paging message 1 sent by satellite 2 when service link 2 is connected. This scenario presents the problem of multiple satellites repeatedly sending the same paging message. This application provides an implementation method to avoid unnecessary paging.

[0293] S1003, Satellite 2 (onboard MME / onboard eNB) obtains the time information of the most recent feeder link being in a connected state (time period T2) of Satellite 2 and the time information of the most recent feeder link being in a connected state of the previous Satellite 1 (time period T1).

[0294] S1004 and Satellite 2 (onboard MME / onboard eNB) determine that paging will be stopped during the current service link connection based on time periods T1 and T2.

[0295] In the fourth embodiment of this application, after the ground MME establishes a feeder link with satellite 1 and satellite 1 receives paging message 1, and after the ground MME establishes a feeder link with satellite 2 and satellite 2 receives paging message 1, when the service link between satellite 2 and UE is in a connected state, satellite 2 can determine to stop paging during the current service link connection period based on the time information of the most recent feeder link connection of satellite 2 and the time information of the most recent feeder link connection of the previous satellite 1, that is, not to send paging message 1.

[0296] In some embodiments, when the service link between satellite 2 and UE is in a connected state, if satellite 2 determines that its T2 time period coincides with the T1 time period of satellite 1, then satellite 2 stops paging during this service link connection period.

[0297] In other embodiments, when the service link between satellite 2 and UE is in a connected state, if satellite 2 determines that the T1 time period of the previous satellite 1 includes the T2 time period of the current satellite 2, then satellite 2 stops paging during the current service link connection period.

[0298] In other words, in this embodiment, satellite 2 (onboard MME / base station) can determine, based on ephemeris information, that there are other satellites with available feeder links to the ground MME at the same time as satellite 2, or that the time during which other satellites are connected to the ground MME includes the time during which satellite 2 is connected to the ground MME; and that other satellites arrive at the UE's TA tracking area first. Satellite 2 then instructs to stop paging within that TAI area.

[0299] In some embodiments, the onboard MME of satellite 2 can instruct the onboard base station of satellite 2 to stop paging within the TA tracking area.

[0300] In other embodiments, the satellite 2's onboard base station determines to stop paging within the TAI area.

[0301] It should be noted that the possible ways in which the satellite side determines to stop paging are similar to the possible ways in which the UE side determines to skip paging listening, which will not be elaborated here.

[0302] S1005, Satellite 1 broadcasts a system message to the UE, which carries an instruction to stop paging.

[0303] S1006. The UE, as instructed, skips paging listening during this service link connection.

[0304] Skipping paging listeners is also known as ignoring paging messages.

[0305] In this embodiment, satellite S2 broadcasts a system message during the time the service link is connected. This system message includes a "stop paging" instruction. Accordingly, the UE receives the system message broadcast by satellite S2 and skips paging listening according to the "stop paging" instruction.

[0306] With the solution proposed in this application, the UE can skip paging listening during the time period when the service link is in a connected state, thereby avoiding unnecessary paging listening and reducing UE power consumption.

[0307] The above, with reference to the accompanying drawings, illustrates the flowchart of the fourth embodiment for transmitting paging messages via the feeder link and service link in store-and-forward mode. The following, with reference to the accompanying drawings, describes the improvements of the fourth embodiment on the UE side.

[0308] like Figure 10B In the original scheme shown, when the ground MME establishes feeder links with both satellite S1 and satellite S2, the ground MME sends paging message 1 to the onboard MMEs of both satellite S1 and S2. As satellite S1 moves along orbit 1, when satellite S1 reaches the TA area registered by the UE and the service link is available, satellite S1 sends paging message 1 to page the UE, and the UE listens to the paging message sent by satellite S1. As satellite S2 moves along orbit 2, when satellite S2 reaches the TA area registered by the UE and the service link is available, satellite S2 sends paging message 1 to page the UE, and the UE still listens to the paging message sent by satellite S1.

[0309] like Figure 10B In the improved scheme shown in this embodiment, the UE listens for paging messages based on the previous satellite (Satellite 1). When the current satellite (Satellite 2) arrives at the tracking area (TA) registered by the UE, Satellite 2 determines that the time information of the most recent feeder link being in a connected state coincides with the time information of the most recent feeder link being in a connected state of Satellite 1, or that the reachability time period of the most recent feeder link of Satellite 1 includes the reachability time period of the most recent feeder link of Satellite 2. In this case, Satellite 2 stops paging the UE. The onboard base station of Satellite 2 can carry the "stop paging" instruction in a system message and broadcast the system message. Correspondingly, the UE can receive the broadcast system message and, according to the "stop paging" instruction, skip paging listening, avoiding unnecessary paging listening and achieving energy saving.

[0310] In the communication method provided in the fourth embodiment of this application, the same paging message from the ground core network can be sent to multiple satellites. For example, when the ground MME establishes feeder links with satellite S1 and satellite S2 respectively, the ground MME sends paging message 1 to the onboard MME of satellite S1 and the onboard MME of satellite S2 respectively. As satellite S1 and satellite S2 move along their respective orbits, when satellite S1 reaches the TA area registered by the UE and the service link is available, satellite S1 sends paging message 1 to page the UE. It should be noted that when satellite S2 reaches the TA area registered by the UE and the service link is available, satellite S2 will not directly send paging message 1 to page the UE. Instead, it will determine whether the conditions for sending paging message 1 are met. Only if the conditions are met will paging message 1 be sent, thus avoiding unnecessary paging power consumption on the satellite side and unnecessary paging monitoring power consumption on the UE side.

[0311] It should be noted that the first to fourth embodiments of this application provide a communication method for an NTN network in store-and-forward mode. This application embodiment can carry system messages containing time information about the most recent connection of the feeder link. This application embodiment can also carry system messages containing indication information to stop paging. In this application embodiment, the UE side can determine whether to skip paging monitoring. This avoids unnecessary paging monitoring power consumption on the UE side.

[0312] Fifth Embodiment

[0313] The fifth embodiment provides a communication method in the case of switching from normal mode to store-and-forward mode.

[0314] Figure 11 The illustration shows the reporting process and paging process of UE support store-and-forward capability information provided in the embodiments of this application.

[0315] S1101, the UE transmits an RRC message to satellite 1. This RRC message can carry information about the UE's ability to support store-and-forward.

[0316] S1102, Satellite 1 receives RRC messages and stores information about the UE's ability to support store-and-forward.

[0317] In some embodiments, for a UE in connected state, the UE can report store-and-forward capability information to the base station on satellite 1 via a dedicated signaling RRC message. The base station on satellite 1 then forwards the information to the MME on satellite 1, where the MME stores the capability. The dedicated signaling RRC message can be UE assistance information (UAI) or an RRC connection completion message.

[0318] In some embodiments, the UE sends information about its store-and-forward capability to the MME via non-access stratum (NAS) signaling.

[0319] For example, during the attach process, the UE can carry its store-and-forward capability information through an attach request or attach complete signaling, thereby sending the store-and-forward capability information to the MME for storage.

[0320] In other embodiments, during the Tracking Area Update (TAU) process, the UE can carry store-and-forward capability information through a TAU request or TAU complete signaling, thereby sending the store-and-forward capability information of the UE to the MME, which then stores it.

[0321] In some other embodiments, when the ground MME needs to page the UE, the ground MME can carry information about the UE's ability to support store-and-forward mode in the paging message sent to the satellite base station.

[0322] S1103, Satellite 1 makes paging decisions on paging messages used to paging the UE based on the UE's store-and-forward capability information.

[0323] S1104. Satellite 1 sends a paging message to the UE in the cell within the UE's tracking area (TA) range in normal mode or store-and-forward mode.

[0324] In one example, when the feeder link of satellite 1 is connected, satellite 1 receives a paging message from the ground MME for paging the UE. When the first serving link of satellite 1 is connected, satellite 1 broadcasts a first system message based on the UE's store-and-forward capability information. This first system message carries the time information of the first feeder link being connected, which is the time or time period of the most recent feeder link being connected before the first serving link began to be connected. Furthermore, the base station on satellite 1, in store-and-forward mode, sends paging messages to cells within the UE's tracking area (TA). The UE can determine whether to listen to the base station's paging message or ignore it based on the time information of the first feeder link being connected.

[0325] In one example, when the feeder link of satellite 1 is connected, satellite 1 receives a paging message from the ground MME for paging the UE. When the first serving link of satellite 1 is connected, satellite 1, based on the UE's store-and-forward capability information, sends a paging message in the cell within the UE's tracking area (TA) in store-and-forward mode. This paging message carries the time information of when the first feeder link was connected, which is the time of the most recent time the feeder link was connected before the first serving link began to be connected. The UE can determine whether to listen to the paging message from the monitoring base station or skip paging listening based on the time information of when the first feeder link was connected.

[0326] For UEs that support store-and-forward mode, the satellite base station can page the UE in store-and-forward mode or in normal mode. Correspondingly, UEs that support store-and-forward mode can listen for paging messages in store-and-forward mode or in normal mode.

[0327] It should be noted that in normal mode, both the serving link and the feeder link are active simultaneously. Paging messages generated by the terrestrial core network (terrestrial MME) can be sent to the onboard MME / eNB at any time, and the onboard eNB can also send paging messages to the UE at any time. In store-and-forward mode, the serving link and the feeder link are not active simultaneously. When the feeder link is active, the terrestrial core network sends paging messages to the onboard MME / eNB; when the serving link is active, the onboard eNB sends paging messages to the UE.

[0328] The following describes the communication method provided in the fifth embodiment of this application when switching from normal mode to store-and-forward mode.

[0329] Figure 12A A schematic diagram of the paging process in mode switching provided in an embodiment of this application is shown.

[0330] The feeder link between S1201 and Satellite 1 is connected, and the service link between Satellite 1 and the UE is also connected. The current NTN communication system is in normal mode.

[0331] S1202. In normal mode, satellite 1 receives paging message 1 for paging the UE. The paging message carries information about the UE's store-and-forward capability. Satellite 1 sends paging message 1 to the UE via the onboard MME and onboard eNB.

[0332] S1203, UE listens for paging in normal mode.

[0333] S1204. When the feeder link switches from an active state to an inactive state, Satellite 1 switches from normal mode to store-and-forward mode.

[0334] S1205. When the feeder link switches from an active state to an inactive state, Satellite 1 broadcasts a third system message through the service link. This third system message contains paging configuration information in store-and-forward mode.

[0335] The UE adopts a first paging listening strategy based on the paging configuration information in store-and-forward mode. The first paging listening strategy includes any one of the following:

[0336] S1206. If paging message 1 is detected but no response is received in normal mode, the UE will directly execute the paging response after switching to store-and-forward mode.

[0337] In this embodiment of the application, for a UE that supports store-and-forward mode, if it switches from normal mode to store-and-forward mode before completing the service in normal mode, the UE is not released when switching to store-and-forward mode.

[0338] In this embodiment of the application, during the process of the satellite switching from normal mode to store-and-forward mode, if the UE hears a paging message but does not complete the paging response in normal mode, then after switching from normal mode to store-and-forward mode, the UE directly completes the paging response in store-and-forward mode.

[0339] If the UE does not receive a paging message in normal mode, then execute S1207, S1208 or S1209.

[0340] S1207. For UEs that only support DRX, if the UE does not hear a paging in normal mode, then the UE continues to listen for paging cycles in store-and-forward mode.

[0341] S1208. For UEs that support eDRX, if the UE does not receive a paging signal in normal mode and has already started a paging window, the UE will continue to listen for paging signals during the remaining time of that paging window under store-and-forward mode.

[0342] In some embodiments, when the same set of paging parameters (referred to as the first paging parameters) is configured in both normal mode and store-and-forward mode, after switching from normal mode to store-and-forward mode, the UE can calculate the paging timing for the remaining time of the paging window based on the first paging parameters, and the UE listens for paging messages at these paging timings.

[0343] In other embodiments, when different paging parameters are configured in normal mode and store-and-forward mode (the first paging parameter is configured in normal mode and the second paging parameter is configured in store-and-forward mode), after switching from normal mode to store-and-forward mode, the UE can calculate the paging timing of the remaining time of the paging window according to the second paging parameter corresponding to the store-and-forward mode, and the UE listens for paging messages at these paging timings.

[0344] S1209. For UEs that support eDRX, if no paging is detected in normal mode and the UE is not within the paging window, then the UE will not perform paging detection in store-and-forward mode.

[0345] In this embodiment of the application, for a UE that supports store-and-forward mode, when switching from normal mode to store-and-forward mode, the UE can use the above method to listen for paging messages in order to avoid unnecessary paging listening and achieve energy saving.

[0346] The following is combined with Figure 12B This section explains the method for calculating paging timing in DRX paging mode.

[0347] In discontinuous reception (DRX) mode, the UE monitors the PDCCH during discontinuous periods, receives paging messages, and triggers the random access channel (RACH) to enter the connected state. During paging, the PDCCH notifies the UE to obtain user data from the corresponding PDSCH. This PDSCH carries upper-layer signaling. The UE can use DRX in both RRC idle and RRC inactive states to reduce power consumption.

[0348] refer to Figure 12B In (a), the UE periodically listens to the paging channel within the paging transmission window (PTW). The PTW contains multiple DRXs, and the UE listens to the paging channel according to the DRX cycle. Within a PTW cycle, only messages within the DRX window can immediately trigger the paging procedure. The UE listens for one paging occasion (PO) in each DRX cycle. A paging frame (PF) is a radio frame and can contain one or more POs or the start point of a PO.

[0349] For UEs supporting DRX, when the satellite base station needs to send a paging message to the UE, the satellite base station first determines the PF (Page Position) based on the UE's identifier (denoted as UE_ID) and DRX information. The UE_ID can be understood as a user group; all users are divided into 1024 groups, and each group of users is paged on the same PO. The UE_ID can be obtained by modulo 1024 using the International Mobile Subscriber Identity (IMSI).

[0350] PF is determined by the following equation:

[0351] SFN mod T = (T div N) * (UE_ID mod N) (Equation 1)

[0352] Where T represents the DRX period, N represents the number of PFs in one DRX period; div represents division operation, mod represents modulo operation, and SFN, calculated by Equation 1, represents the frame number of the PF.

[0353] PO is determined by the following equation:

[0354] i_s=floor(UE_ID / N)mod Ns (Equation 2)

[0355] Where Ns represents the number of POs in a PF, floor() represents the floor operation, and the index i_s obtained by Equation 2 points to the PO position.

[0356] After determining the frame number of the PF, the satellite base station determines the paging opportunity PO of the UE based on the number of POs Ns in the PF indicated by the frame number and the number of PFs N in one DRX cycle. Then, the satellite base station sends a paging message on this paging opportunity PO.

[0357] In some embodiments, when switching from normal mode to store-and-forward mode, the satellite base station can calculate the paging opportunity (PO) and send the calculated paging opportunity (PO) to the UE. Thus, the UE can determine whether a paging window has started.

[0358] In other embodiments, when switching from normal mode to store-and-forward mode, the UE can use the above method to calculate the paging timing PO and determine to continue listening for a number of paging cycles.

[0359] For UEs that only support DRX, if the UE does not receive a paging message in normal mode, it will continue to listen for paging cycles after switching to store-and-forward mode. The specific number of paging cycles can be set according to actual usage requirements.

[0360] The following explains how to calculate the paging timing for each eDRX paging mode.

[0361] refer to Figure 12B In (b) of the diagram, under the Extended Discontinuous Receive (eDRX) paging mode, the UE periodically goes into sleep mode and only listens for paging messages from the network when it is awake. eDRX is more power-efficient than DRX. eDRX includes a PTW (Paging Terminal Winding) where the UE listens for paging messages according to DRX within the PTW, and ignores listening to paging messages outside the PTW, allowing the UE to remain in sleep mode.

[0362] For UEs supporting eDRX, the satellite base station first determines the paging superframe H-SFN for the UE based on the eDRX and the UE identifier. One paging superframe equals 1024 paging frames. Then, the satellite base station determines a paging window PTW within the paging superframe for sending and receiving paging messages. Determining the PTW includes determining the start and end radio frames of the PTW.

[0363] In some embodiments, when switching from normal mode to store-and-forward mode, the satellite base station can calculate the paging window PTW and send the calculated paging window PTW to the UE. Thus, the UE can determine whether a paging window has been started.

[0364] In other embodiments, when switching from normal mode to store-and-forward mode, the UE can use the above method to calculate the paging window PTW and determine whether the paging window has been started.

[0365] For UEs supporting eDRX, if a UE does not receive a paging request in normal mode and has already started a paging window, the UE will continue listening for paging during the remaining time of that paging window after switching to store-and-forward. If a UE does not receive a paging request in normal mode and is not within a paging window, the UE will not perform paging listening after switching to store-and-forward.

[0366] The above, with reference to the accompanying drawings, illustrates the flowchart of the communication method provided in the fifth embodiment for switching from normal mode to store-and-forward mode. The improvements of the fifth embodiment on the UE side are described below with reference to the accompanying drawings.

[0367] like Figure 13 The original scheme shown depicts a scenario where, in normal mode, satellite 1 pages the UE, and the UE listens for the paging. Even when switching from normal mode to store-and-forward mode, the UE still listens for the paging.

[0368] like Figure 13 The improved scheme shown allows the UE to listen to the paging from Satellite 1 in normal mode. When switching from normal mode to store-and-forward mode, the UE can choose to continue listening to the paging for a period of time or stop listening, depending on the specific circumstances, to avoid unnecessary paging and achieve energy savings.

[0369] It should be noted that the fifth embodiment of this application provides a communication method when an NTN network switches from normal mode to store-and-forward mode. This embodiment can transmit the UE's store-and-forward capability information to the MME. This embodiment can also allow the MME to instruct the base station that the UE supports store-and-forward. This embodiment provides a paging monitoring strategy on the UE side during the satellite's switch from normal mode to store-and-forward mode. This avoids unnecessary paging monitoring power consumption on the UE side.

[0370] It should be noted that in all the embodiments described above in this application, the base station can be either a 4G base station (eNB) or a 5G base station (gNB). The mobility management entity can be either a 4G MME or a 5G AMF. The specific configuration can be determined according to actual usage requirements.

[0371] It should also be noted that the communication methods provided in the various embodiments of this application can be applied to the NTN on-board regeneration architecture (satellite-borne eNB) of 4G systems, and can also be applied to the NTN on-board regeneration architecture (satellite-borne gNB) of 5G systems.

[0372] The above text combined Figures 1A to 13The method embodiments of this application are described in detail below, in conjunction with... Figures 14 to 16 This section describes the apparatus embodiments of this application. It should be understood that the descriptions of the method embodiments correspond to the descriptions of the apparatus embodiments; therefore, any parts not described in detail can be found in the foregoing method embodiments.

[0373] Figure 14 This is a schematic block diagram of a communication device provided in an embodiment of this application. Figure 14 As shown, the communication device 1400 includes a transceiver module 1401 and a processing module 1402.

[0374] The transceiver module 1401 is used to receive a first system message from a first base station deployed on the first satellite when the first service link between the first satellite and the UE is in a connected state. The first system message carries time information of the first feeder link being in a connected state. The time information of the first feeder link being in a connected state is used to indicate the time or time period when the first satellite was in a connected state of the feeder link before the first service link started to be in a connected state.

[0375] The processing module 1402 is used to determine whether to listen to or ignore the first paging message of the first base station based on the time information of the first feeder link being in a connected state.

[0376] In some embodiments, the transceiver module 1401 is further configured to report the UE's ability to support store-and-forward mode to a first base station deployed on a first satellite; and to receive a third system message, the third system message containing paging configuration information of the first base station in store-and-forward mode.

[0377] The processing module 1402 is further configured to determine, based on the paging configuration information in the store-and-forward mode, whether to listen to or ignore paging messages when switching from normal mode to store-and-forward mode.

[0378] In one possible implementation, the device 1400 can be used to implement the steps corresponding to the UE in the NTN network in the methods shown in the first to fifth embodiments described above.

[0379] Figure 15 This is a schematic block diagram of a communication device provided in an embodiment of this application. Figure 15 As shown, the communication device 1500 includes a transceiver module 1501 and a processing module 1502.

[0380] The transceiver module 1501 is used to broadcast a first system message when the first service link of the first satellite is in a connected state. The first system message carries the time information of the first feeder link being in a connected state. The time information of the first feeder link being in a connected state is used to indicate the time or time period when the first satellite was in a connected state of the feeder link before the first service link started to be in a connected state.

[0381] Processing module 1502 is used to determine whether to paging or stop paging the UE when the first service link of the first satellite is in a connected state, based on the time information of the first feeder link being in a connected state. The time information of the first feeder link being in a connected state is used to indicate the time or time period when the first satellite was in a connected state most recently before the first service link started to be in a connected state.

[0382] In some embodiments, the transceiver module 1501 is further configured to receive UE capability information supporting store-and-forward mode; and broadcast a third system message, the third system message containing paging configuration information in store-and-forward mode.

[0383] In one possible implementation, the device 1500 can be used to implement the steps corresponding to the satellite side within the NTN network in the methods shown in the first to fifth embodiments described above.

[0384] It should be understood that devices 1400 and 1500 are embodied in the form of functional modules. The term "module" here can refer to application-specific integrated circuits (ASICs), electronic circuits, processors (e.g., shared processors, proprietary processors, or group processors, etc.) and memories for executing one or more software or firmware programs, integrated logic circuits, and / or other suitable components supporting the described functions. In an alternative example, those skilled in the art will understand that device 1400 can be specifically defined as the UE in the above embodiments, and device 1400 can be used to execute the various processes and / or steps corresponding to the user equipment in the above method embodiments. Device 1500 can be specifically defined as the spaceborne network equipment in the above embodiments, and device 1500 can be used to execute the various processes and / or steps corresponding to the spaceborne network equipment in the above method embodiments. To avoid repetition, further details are omitted here. For example, spaceborne network equipment may include a spaceborne MME and a spaceborne eNB, and terrestrial network equipment may include a gateway station and a terrestrial MME.

[0385] The aforementioned device 1400 has the function of implementing the corresponding steps performed by the UE in the aforementioned method, and the aforementioned device 1500 has the function of implementing the corresponding steps performed by the spaceborne network equipment in the aforementioned method. These functions can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the aforementioned functions.

[0386] In embodiments of this application, devices 1400 and 1500 may also be chips, such as a system-on-a-chip (SOC) or a modem. Correspondingly, the receiving module and the transmitting module may be the transceiver circuits of the chip, and are not limited herein.

[0387] Figure 16 A schematic structural diagram of a communication device according to an embodiment of this application. Figure 16 The dashed lines indicate that the unit or module is optional. The device 1600 can be used to implement the methods described in the above method embodiments. The device 1600 can be a chip, a UE, or a satellite-side network device.

[0388] Apparatus 1600 may include one or more processors 1601. The processor 1601 may support apparatus 1600 in implementing the methods described in the preceding method embodiments. The processor 1601 may be a general-purpose processor or a special-purpose processor. For example, the processor may be a central processing unit (CPU). Alternatively, the processor may be other general-purpose processors, digital signal processors (DSPs), ASICs, field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0389] The apparatus 1600 may further include one or more memories 32. A program is stored on memory 1602 that can be executed by processor 1601, causing processor 1601 to perform the methods described in the preceding method embodiments. Memory 1602 may be independent of processor 1601 or integrated into processor 1601.

[0390] The device 1600 may also include a transceiver 1603. The processor 1601 can communicate with other devices or chips via the transceiver 1603. For example, the processor 1601 can send and receive data with other devices or chips via the transceiver 1603.

[0391] This application also provides a computer-readable storage medium for storing a program. This computer-readable storage medium can be applied to a UE or spaceborne network device provided in this application embodiment, and the program causes a computer to execute the methods performed by the UE or spaceborne network device in various embodiments of this application.

[0392] This application also provides a computer program product. The computer program product includes a program. This computer program product can be applied to a UE or spaceborne network device provided in this application embodiment, and the program causes a computer to execute the methods performed by the UE or spaceborne network device in various embodiments of this application.

[0393] This application also provides a computer program. This computer program can be applied to a UE or spaceborne network device provided in this application embodiment, and the computer program causes a computer to execute the methods performed by the UE or spaceborne network device in various embodiments of this application.

[0394] It should be understood that in the embodiments of this application, "B corresponding to A" means that B is associated with A, and B can be determined based on A. However, it should also be understood that determining B based on A does not mean that B is determined solely based on A; B can also be determined based on A and / or other information.

[0395] It should be understood that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0396] 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.

[0397] In this application, entity A sends information to entity B, either directly or indirectly through other entities. Similarly, entity B receives information from entity A, either directly or indirectly through other entities. Entities A and B can be RAN nodes or terminals, or modules within RAN nodes or terminals. Information transmission and reception can be between RAN nodes and terminals, such as between a base station and a terminal; between two RAN nodes, such as between a CU and a DU; or between different modules within a single device, such as between a terminal chip and other modules of the terminal, or between a base station chip and other modules of the base station.

[0398] 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.

[0399] 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.

[0400] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0401] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can read or a data storage device such as a server or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., digital video discs, DVDs) or semiconductor media (e.g., solid-state disks, SSDs), etc.

[0402] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A communication method applied to a user equipment (UE), characterized in that, The communication method comprises: receiving a first system message from a first base station deployed on a first satellite when a first service link between the first satellite and the UE is in a connected state, the first system message carrying time information of a first feeder link being in the connected state, the time information of the first feeder link being in the connected state being used to indicate a time point or a time period of the first satellite being in the connected state of the feeder link last time before the first service link starts to be in the connected state; determining, according to the time information of the first feeder link being in the connected state, whether to listen to or ignore listening to a first paging message of the first base station.

2. The method of claim 1, wherein, The time information of the first feeder link being in the connected state comprises at least one of the following: a time point of the first feeder link starting to be in the connected state, a duration of the first feeder link being in the connected state, and a time point of the first feeder link ending to be in the connected state.

3. The method of claim 2, wherein, The time point is represented in the form of: an absolute time point; or a first relative time point, the first relative time point being indicated by an offset of system time UTC, the offset being in seconds; or a second relative time point, the second relative time point being indicated by an offset of a reference time point of a satellite at a start time point of a current cell downlink subframe, the offset being in a number of radio frames, a number of subframes, and / or seconds. The determining, according to the time information of the first feeder link being in the connected state, whether to listen to or ignore listening to the first paging message of the first base station comprises:

4. The method according to any one of claims 1 to 3, characterized in that, determining to listen to the first paging message of the first base station in a case where it is determined, according to the time information of the first feeder link being in the connected state, that the UE does not detect that the first satellite provides service for a cell coverage range where the UE is located through a service link within a first time period; or determining to ignore listening to the first paging message of the first base station in a case where it is determined, according to the time information of the first feeder link being in the connected state, that the UE detects that the first satellite provides service for the cell coverage range where the UE is located through the service link within the first time period; wherein the first time period is after a last time of the first satellite being in the connected state of the feeder link and before a start time of the first service link being in the connected state. The determining, according to the time information of the first feeder link being in the connected state, whether to listen to or ignore listening to the first paging message of the first base station comprises:

5. The method according to any one of claims 1 to 3, characterized in that, determining, according to the time information of the first feeder link being in the connected state and time information of a second feeder link of a second satellite being in the connected state, whether to listen to or ignore listening to the first paging message of the first base station; wherein a second service link between the UE and the second satellite is in the connected state before the first service link between the UE and the first satellite starts to be in the connected state, and the time information of the second feeder link being in the connected state is used to indicate a time point or a time period of the second satellite being in the connected state of the feeder link last time before the second service link starts to be in the connected state. ​ 6. The method of claim 5, wherein, The method comprises: determining, according to the time information of the first feeder link being in the connected state and the time information of the second feeder link of the second satellite being in the connected state, whether to listen to or ignore listening to the first paging message of the first base station, comprising: in the case that there is no intersection between the time information of the first feeder link being in the connected state and the time information of the second feeder link being in the connected state, determining to listen to the first paging message of the first base station; or, 7. The method according to any one of claims 1 to 6, characterized in that, in the case that the time information of the first feeder link being in the connected state coincides with the time information of the second feeder link being in the connected state, or the time period of the second feeder link being in the connected state contains the time period of the first feeder link being in the connected state, determining to listen to the first paging message of the first base station. The method further comprises: when the first service link is in the connected state, receiving a second system message from the first base station, the second system message carrying a first indication message for indicating to stop paging; 8. The method of claim 7, wherein, determining, according to the first indication message, to ignore listening to the first paging message of the first base station. 9.A communication method applied to a first base station deployed on a first satellite, the method comprising: The first indication message is used to indicate to stop paging in the cell broadcasting the second system message. The method comprises:

10. The method of claim 9, wherein, when the first service link of the first satellite is in the connected state, broadcasting a first system message, the first system message carrying time information of the first feeder link being in the connected state, the time information of the first feeder link being in the connected state being used to indicate the time point or time period of the last time when the first satellite is in the connected state before the first service link starts to be in the connected state.

11. The method of claim 10, wherein, The time information of the first feeder link being in the connected state comprises at least one of the following: a time point when the first feeder link starts to be in the connected state, a duration of the first feeder link being in the connected state, and a time point when the first feeder link ends to be in the connected state. The time point is represented in the form of: an absolute time point; or a first relative time point, the first relative time point being indicated by an offset of system time UTC, the offset being in seconds; or 12. The method according to any one of claims 9 to 11, characterized in that, a second relative time point, the second relative time point being indicated by an offset of a reference time point of a downlink subframe of a satellite in a current cell, the offset being in the number of radio frames, the number of subframes, and / or seconds. Before the first service link of the first satellite is in the connected state, the method further comprises:

13. The method of claim 12, wherein, when the first feeder link of the first satellite is in the connected state, receiving a first paging message for paging a UE from a first mobility management entity (MME). The method comprises: determining, according to the time information of the first feeder link being in the connected state, whether to page or stop paging the UE, comprising: in the case that it is determined, according to the time information of the first feeder link being in the connected state, that the first satellite has not been detected to provide service for the cell in which the UE is located through a service link within a first time period, determining to send the first paging message; or, in the case that it is determined, according to the time information of the first feeder link being in the connected state, that the first satellite has been detected to provide service for the cell in which the UE is located through a service link within a first time period, determining to stop paging the UE. determining to stop paging, in a case that the first satellite provides service for a cell coverage range where the UE is located via a service link during a first time period according to time information that the first feeder link is in a connected state; wherein the first time period is a time period from a last time that the first feeder link is in the connected state to a time before the first service link is in the connected state.

14. The method of claim 12, wherein, The determining to page or stop paging the UE according to the time information that the first feeder link is in the connected state comprises: determining to page or stop paging the UE according to the time information that the first feeder link is in the connected state and time information that a second feeder link of a second satellite is in the connected state; wherein a second service link between the second satellite and the UE is in the connected state before the first service link between the first satellite and the UE is in the connected state; and the time information that the second feeder link is in the connected state is a time point or a time period from a last time that the second satellite is in the connected state before the second service link is in the connected state.

15. The method of claim 14, wherein, The determining to page or stop paging the UE according to the time information that the first feeder link is in the connected state and the time information that the second feeder link is in the connected state comprises: determining to send the first paging message, in a case that the time information that the first feeder link is in the connected state and the time information that the second feeder link is in the connected state do not have an intersection; or determining to stop paging the UE, in a case that the time information that the first feeder link is in the connected state coincides with the time information that the second feeder link is in the connected state, or a time period that the second feeder link is in the connected state contains a time period that the first feeder link is in the connected state.

16. The method according to any one of claims 13 to 15, characterized in that, In the case of determining to stop paging the UE, the method further comprises: sending a second system message, the second system message carrying a first indication message used to indicate to stop paging.

17. The method of claim 16, wherein, The first indication message is used to indicate to stop paging in a cell where the second system message is broadcast. 18.A communication method applied to a user equipment (UE), comprising: The communication method comprises: receiving a second system message from a first base station deployed on a first satellite, in a case that a first service link between the UE and the first satellite is in a connected state, the second system message carrying a first indication information used to indicate to stop paging in a cell where the second system message is broadcast; ignoring to listen to a paging message of the first base station according to the first indication information. 19.A communication method applied to a first base station deployed on a first satellite, the method comprising: The method comprises: determining to page or stop paging a user equipment (UE) according to time information that a first feeder link is in a connected state, in a case that a first service link of a first satellite is in the connected state, the time information that the first feeder link is in the connected state being used to indicate a time point or a time period from a last time that the first satellite is in the connected state before the first service link is in the connected state.

20. The method of claim 19, wherein, The time information that the first feeder link is in the connected state includes at least one of: a time when the first feeder link starts to be in the connected state, a duration that the first feeder link is in the connected state, and a time when the first feeder link ends to be in the connected state.

21. The method of claim 20, wherein, The time is represented in the form of: an absolute time; or a first relative time, which is indicated by an offset of system time UTC, and the offset is in seconds; or a second relative time, which is indicated by an offset of a reference time of a satellite at a start time of a current cell downlink subframe, and the offset is in a number of radio frames, a number of subframes, and / or seconds.

22. The method of any one of claims 19-21, wherein, The method further includes: in a case where it is determined to stop paging the UE, broadcasting a second system message carrying a first indication message for indicating to stop paging.

23. The method of claim 22, wherein, The first indication message is used to indicate to stop paging in a cell broadcasting the second system message.

24. The method of any one of claims 19-23, wherein, Before the first service link of the first satellite is in the connected state, the method further includes: receiving, from a first mobility management entity MME, a first paging message for paging a UE when the first feeder link of the first satellite is in the connected state; The determining, according to the time information that the first feeder link is in the connected state, to page or stop paging a user equipment UE includes: determining, according to the time information that the first feeder link is in the connected state, to page or stop paging the UE.

25. The method of claim 24, wherein, The determining, according to the time information that the first feeder link is in the connected state, to page or stop paging a user equipment UE includes: in a case where it is determined, according to the time information that the first feeder link is in the connected state, that the first satellite does not provide service for a cell where the UE is located within a first time period, determining to send the first paging message; or in a case where it is determined, according to the time information that the first feeder link is in the connected state, that the first satellite provides service for the cell where the UE is located within the first time period, determining to stop paging the UE; wherein the first time period is from after a last time when the first feeder link of the first satellite is in the connected state to before a start time of the first service link being in the connected state.

26. The method of claim 24, wherein, The determining, according to the time information that the first feeder link is in the connected state, to page or stop paging a user equipment UE includes: determining, according to the time information that the first feeder link is in the connected state and time information that a second feeder link of a second satellite is in the connected state, to page or stop paging the UE; wherein a second service link between the second satellite and the UE is in the connected state before a start time of the first service link between the first satellite and the UE being in the connected state, and the time information that the second feeder link is in the connected state is a time or a time period when the second satellite is in the connected state at a last time before the start time of the second service link being in the connected state.

27. The method of claim 26, wherein, The determining the paging or stopping the paging of the UE according to the time information that the first feeder link is in the connected state and the time information that the second feeder link of the second satellite is in the connected state comprises: In the case that the time information that the first feeder link is in the connected state and the time information that the second feeder link is in the connected state have no intersection, it is determined to send the first paging message; or, In the case that the time information that the first feeder link is in the connected state coincides with the time information that the second feeder link is in the connected state, or the time period that the second feeder link is in the connected state contains the time period that the first feeder link is in the connected state, it is determined to stop the paging of the UE.

28. The method of claim 27, wherein, The first paging message is received in the time period that the time information that the first feeder link is in the connected state and the time information that the second feeder link is in the connected state have intersection. 29.A method of communication for a user equipment (UE), comprising: The method comprises: reporting the capability information of the UE supporting the store-and-forward mode to a first base station deployed on a first satellite; receiving a third system message, the third system message containing paging configuration information of the first base station; determining a paging listening strategy in the store-and-forward mode according to the paging configuration information.

30. The method of claim 29, wherein, The paging configuration information in the store-and-forward mode comprises a paging period and / or a paging density; wherein the paging period takes a value of M subframes; the paging density is that there are M paging subframes in one radio frame, or there are Y paging subframes in X radio frames, M, N, X and Y are all positive integers.

31. The method of claim 29 or 30, wherein, The method further comprises: listening to a paging message in the store-and-forward mode and / or listening to a paging message in a normal mode; wherein the store-and-forward mode is used to represent a communication mode when the service link and the feeder link are not in the effective state at the same time, and the normal mode is used to represent a communication mode when the service link and the feeder link are in the effective state at the same time.

32. The method of claim 31, wherein, The listening to the paging message in the store-and-forward mode comprises: calculating a time position of listening to the paging message in the store-and-forward mode; listening to the paging message at the calculated time position.

33. The method of any one of claims 29-32, wherein, The paging configuration information of the first base station comprises first paging configuration information corresponding to the normal mode, and second paging configuration information corresponding to the store-and-forward mode; The determining the paging listening strategy in the store-and-forward mode according to the paging configuration information comprises: in the case that the first paging configuration information and the second paging configuration information are the same, determining to adopt a first paging listening strategy in the store-and-forward mode, wherein a first paging period and / or a first paging density adopted by the first paging listening strategy are determined according to the first paging configuration information; in the case that the first paging configuration information and the second paging configuration information are different, determining to adopt a second paging listening strategy in the store-and-forward mode, wherein a second paging period and / or a second paging density adopted by the second paging listening strategy are determined according to the second paging configuration information.

34. The method of claim 33, wherein, When switching from the normal mode to the store-and-forward mode, the method further comprises: If the UE supports a discontinuous reception (DRX) paging mode, the UE continues to monitor for paging messages using the determined first paging monitoring strategy or the second paging strategy and stops monitoring for paging messages after a number of paging cycles; or If the UE supports an extended discontinuous reception (eDRX) paging mode and has started a time window, the UE continues to monitor for paging messages using the determined first paging monitoring strategy or the second paging strategy at paging occasions in a remaining time of the time window; or If the UE supports the eDRX paging mode but has not started a time window, the UE stops monitoring for paging messages.

35. A method of communication, deployed at a first base station on a first satellite, comprising: The method comprises: receiving capability information that the UE supports a store-and-forward mode; broadcasting a third system message, the third system message containing paging configuration information of the first base station; wherein the paging configuration information of the first base station comprises first paging configuration information corresponding to a normal mode and second paging configuration information corresponding to the store-and-forward mode.

36. The method of claim 35, wherein, The paging configuration information in the store-and-forward mode comprises a paging cycle and / or a paging density; wherein the paging cycle takes a value of M subframes; the paging density is that there are M paging subframes in one radio frame, or there are Y paging subframes in X radio frames, M, N, X and Y are positive integers.

37. The method of claim 35 or 36, wherein, The method further comprises: receiving a first paging message from a second MME, the first paging message carrying capability information that the UE supports the store-and-forward mode; based on the capability information that the UE supports the store-and-forward mode, delivering the first paging message to the UE in the store-and-forward mode and / or in a normal mode.

38. An electronic device, comprising: The electronic device comprises one or more processors and a memory; The memory is coupled to the one or more processors, and the memory is configured to store computer program codes, the computer program codes comprising computer instructions, and the one or more processors are configured to invoke the computer instructions to cause the electronic device to perform the method according to any one of claims 1 to 37.

39. A communication system, characterized by The communication system comprises a user equipment (UE) and a first satellite; the first satellite comprises a first base station and a second mobility management entity (MME); the second MME is configured to send a first paging message for paging the UE to the first base station; The UE performs the method according to any one of claims 1 to 8, and the first base station performs the method according to any one of claims 9 to 17; or The UE performs the method according to claim 18, and the first base station performs the method according to any one of claims 19 to 28; or The UE performs the method according to any one of claims 29 to 34, and the first base station performs the method according to claims 35 to 37.

40. A computer-readable storage medium, characterized in that, The computer readable storage medium comprises instructions, which, when executed on an electronic device, cause the electronic device to perform the method according to any one of claims 1 to 37.

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