A communication method, terminal device, and one or more computer-readable, non-transient storage media.

Abstract

Provided are a communication method, a terminal device, and a network device. The method comprises: a terminal device executes a first operation on the basis of a first moment, wherein the first moment is a change moment of a satellite corresponding to a first cell of the terminal device, and the first operation comprises one or more of the following operations: a second operation that the terminal device starts to execute by using ephemeris information of the changed satellite; and a third operation executed by the terminal device in response to the change of the satellite corresponding to the first cell. The terminal device may execute the first operation to deal with a satellite change. Taking the first operation comprising the second operation as an example, the terminal device may determine, on the basis of the change moment of the satellite, the moment of starting use of the ephemeris information of the changed satellite, such that the use of the ephemeris information better conforms to the actual situation. Taking the first operation comprising the third operation as an example, the terminal device can avoid a communication abnormality, caused by a satellite change, to the extent possible by executing the third operation.

Description

1 / 55 “COMMUNICATION METHOD, TERMINAL DEVICE AND ONE OR MORE NON-TRANSIENT COMPUTER-READABLE STORAGE MEDIA” Field of invention

[001] The various embodiments described in this disclosure generally relate to the field of communication technology and, more specifically, to a method, a terminal device and a network device for communication. Background of the Invention

[002] With the development of technology, non-terrestrial network (NTN) communication has correspondingly emerged. NTN communication can be implemented based on a satellite or other non-terrestrial communication devices. Therefore, in some embodiments, NTN communication can also be called satellite communication. Since a satellite can move, even if a terminal device does not move, the satellites serving it can change. The technology related to how the terminal device should respond to the change of satellites has not yet been proposed in some cases. Brief Description of the Invention

[003] This disclosure provides a method, a terminal device, and a network device for communication. Several aspects of this disclosure are described below.

[004] In the first aspect, a method for communication is provided, including: performing, by means of a terminal device, a first operation according to a first moment. The first moment refers to a moment of exchange of a satellite corresponding to a first cell to the terminal device. The first operation includes one or more of the following operations: a second operation performed by means of the device Petition 870250075840, dated 08 / 27 / 2025, page 10 / 87 2 / 55 terminal after the terminal device starts using ephemeris information from a changed satellite; and a third operation performed by the terminal device in response to the change of the satellite corresponding to the first cell.

[005] In a second aspect, a method of communication is provided, including: determining, by means of a network device, a first moment, wherein the first moment refers to a moment of switching from a satellite corresponding to a first cell to a terminal device; and configuring, by means of the network device, one or more of the following information according to the first moment: ephemeris information of a changed satellite; and a first operation performed by means of the terminal device according to the first moment. The first operation includes one or more of the following operations: a second operation performed by means of the terminal device after the terminal device starts using the ephemeris information of the changed satellite; and a third operation performed by means of the terminal device in response to the switching of the satellite corresponding to the first cell.

[006] In a third aspect, a terminal device is provided, including: an execution unit configured to perform a first operation according to a first moment. The first moment refers to a moment of switching from a satellite corresponding to a first cell to the terminal device, and the first operation includes one or more of the following operations: a second operation performed by means of the terminal device after the terminal device starts using ephemeris information from a changed satellite; and a third operation performed by means of the terminal device in response to the switching of the satellite corresponding to the first cell.

[007] In a fourth aspect, a network device is provided, Petition 870250075840, dated 08 / 27 / 2025, page 11 / 87 3 / 55 including: a determination unit configured to determine a first moment, where the first moment refers to a change of satellite corresponding to a first cell for a terminal device; and a configuration unit configured to configure one or more of the following information according to the first moment: ephemeris information of a changed satellite and a first operation performed by the terminal device according to the first moment. The first operation includes one or more of the following operations: a second operation performed by the terminal device after the terminal device starts using ephemeris information from the changed satellite; and a third operation performed by the terminal device in response to the change of satellite corresponding to the first cell.

[008] In a fifth aspect, a terminal device is provided, including a memory and at least one processor. The memory is configured to store one or more computer programs, and the at least one processor is configured to call the one or more computer programs in memory to cause the terminal device to perform some or all of the operations of the communication method according to the first aspect.

[009] In a sixth aspect, a network device is provided, including a memory, at least one processor, and a transceiver. The memory is configured to store one or more computer programs, and the at least one processor is configured to call the one or more computer programs in memory to cause the network device to perform some or all of the operations of the communication method according to the second aspect.

[010] In a seventh aspect, a communication system is provided, including the terminal device and / or the network device mentioned above. In some embodiments, the system may include further... Petition 870250075840, dated 08 / 27 / 2025, page 12 / 87 4 / 55 devices that interact with the terminal device or network device in the technical solutions provided in the embodiments of this disclosure.

[011] In an eighth aspect, a computer-readable storage medium is provided. The computer-readable storage medium is configured to store computer programs which, when executed by one or more processors, cause the terminal device and / or the network device to perform some or all of the operations of the communication methods in accordance with the various aspects above.

[012] In a ninth aspect, a computer program product is provided, including a non-transient, computer-readable storage medium that stores computer programs, which are executable by one or more processors to cause the terminal device and / or the network device to perform part or all of the operations of the communication method, according to the various aspects above. In some embodiments, the computer program product may be a software package.

[013] In a tenth aspect, a chip is provided, including a memory and at least one processor. The at least one processor is configured to call and execute computer programs from memory in order to implement some or all of the operations of the communication methods, according to the various aspects above.

[014] In the present disclosure, the terminal device can perform the first operation corresponding to the satellite change. For example, the first operation includes the operation performed by the terminal device after the terminal device starts using the ephemeris information from the changed satellite (i.e., the second operation). The terminal device can determine when the terminal device starts using the information from Petition 870250075840, dated 08 / 27 / 2025, page 13 / 87 5 / 55 satellite ephemeris changes based on the timing of the satellite change, so that the use of ephemeris information can be more aligned with real-world conditions. As another example, the first operation includes the operation performed by the terminal device in response to the satellite change (i.e., the third operation). With the third operation, the terminal device can avoid communication anomalies caused by the satellite change as much as possible. Brief Description of the Figures

[015] Figure 1 is a schematic diagram illustrating a wireless communication system to which some embodiments of the present disclosure are applicable.

[016] Figure 2A is a schematic diagram illustrating NTN communication in bent tube mode.

[017] Figure 2B is a schematic diagram illustrating NTN communication in regeneration mode.

[018] Figure 3A is a schematic diagram illustrating a mobile cell according to some embodiments.

[019] Figure 3B is a schematic diagram that illustrates a fixed cell according to some embodiments.

[020] Figure 4 is a schematic diagram illustrating a satellite change process in which the PCI remains unchanged.

[021] Figure 5 is a schematic diagram that illustrates the determination of the satellite's position at a given time using ephemeris information.

[022] Figure 6 is a schematic diagram illustrating the provision of new ephemeris information by a network device before the current ephemeris information becomes invalid.

[023] Figure 7 is a schematic diagram that illustrates a Petition 870250075840, dated 08 / 27 / 2025, page 14 / 87 6 / 55 effective moment of the ephemeris information corresponding to the altered satellite.

[024] Figure 8 is a schematic flowchart of a communication method according to some ways of carrying out the present dissemination.

[025] Figure 9 is a schematic diagram of an implicit indication of whether the first ephemeris information corresponds to a new satellite.

[026] Figure 10 is a schematic diagram that illustrates a list of ephemeris information according to some forms of carrying out the present dissemination.

[027] Figure 11 is an example diagram illustrating a subframe boundary jitter according to some embodiments of the present disclosure.

[028] Figure 12 is an example diagram that illustrates an RLM process based on a second counter and a first timer according to some embodiments.

[029] Figure 13 is a schematic diagram illustrating the structure of a terminal device according to some embodiments of the present disclosure.

[030] Figure 14 is a schematic diagram illustrating the structure of a network device according to some embodiments of the present disclosure.

[031] Figure 15 is a schematic diagram illustrating the structure of a communication device according to some embodiments of the present disclosure. Detailed Description of the Invention

[032] The technical solutions in this disclosure will be described below together with the attached drawings. Petition 870250075840, dated 08 / 27 / 2025, page 15 / 87 7 / 55 Communication system

[033] Figure 1 illustrates a wireless communication system (100) to which some embodiments of the present disclosure are applicable. The wireless communication system (100) may include communication devices, and the communication devices may include a network device (110) and a terminal device (120). The network device (110) may be in communication with the terminal device (120).

[034] Figure 1 illustrates, by way of example, a network device and two terminal devices. In some embodiments, the wireless communication system (100) may include a plurality of network devices, and a coverage area of ​​each network device may encompass a different number of terminal devices, which are not limited in the embodiments of the present disclosure.

[035] In some embodiments, the wireless communication system (100) may also include other network entities, such as network controllers, mobility management entities and the like, which are not limited to the embodiments of this disclosure.

[036] It should be understood that the technical solutions in the embodiments of this disclosure can be applied to various communication systems, such as 5th generation (5G) systems or new radio systems (NR), long-term evolution (LTE) systems, frequency division duplex (FDD) systems, LTE time division duplex (TDD) systems and the like. The technical solutions provided in this disclosure can also be applied to future communication systems, such as sixth-generation mobile communication systems, satellite communication systems and the like.

[037] The terminal device in the embodiments of this disclosure may also be referred to as a user equipment (UE), an access terminal, a subscriber unit, a station. Petition 870250075840, dated 08 / 27 / 2025, page 16 / 87 8 / 55 subscriber, a mobile radio station, a mobile station (MS), a mobile terminal (MT), a remote station, a remote terminal, a mobile device, a user terminal, a terminal, a device for wireless communication, a user agent or a user device. The terminal device in the embodiments of this disclosure may be a device that provides voice and / or data connectivity to a user and may be used for communication between people, objects and machines, such as portable devices and vehicle-mounted devices that have a wireless connection function.The terminal device in the embodiments of this disclosure may be a mobile phone, a tablet (Pad), a notebook, a palmtop, a mobile internet device (MID), a wearable device, a virtual reality (VR) device, an augmented reality (AR) device, a wireless terminal in industrial control, a wireless terminal in autonomous driving, a wireless terminal in remote medical surgery, a wireless terminal in smart networking, a wireless terminal in transport security, a wireless terminal in smart cities, and a wireless terminal in smart homes, and the like. In some embodiments, the UE may function as a base station. For example, the UE may function as a scheduling entity, providing a side link signal between UEs in vehicle-to-everything (V2X) communication or device-to-device (D2D) communication, or the like.For example, a cell phone and a car communicate using a sidelink signal, or a cell phone and a smart home device communicate without relaying a communication signal through a base station.

[038] The network device in the embodiments of this disclosure may be a device for communication with the terminal device. The network device may include an access network device that can provide communication coverage for a specified geographic area and can communicate with the terminal device (120) in the coverage area. The Petition 870250075840, dated 08 / 27 / 2025, page 17 / 87 9 / 55 access network device may also be referred to as radio access network device, base station or similar. The access network device in the embodiments of this disclosure may refer to a radio access network (RAN) node (or device) that connects a terminal device to a wireless network.The access network device may broadly include, or be equivalent to, the following terms: a B node (NodeB), an evolved NodeB (eNB), a next-generation NodeB (gNB), a relay station, an access point, a transmit / receive point (TRP), a transmit point (TP), a master eNodeB (MeNB), a secondary eNodeB (SeNB), a multi-pattern radio node (MSR), a home base station, a network controller, an access node, a wireless node, an access point (AP), a transmit node, a transceiver node, a baseband unit (BBU), a remote radio unit (RRU), an active antenna unit (AAU), a remote radio head (RRH), a central unit (CU), a distributed unit (DU), a positioning node, and the like. The base station may be a macro base station, a micro base station, a relay node, a donor node, or similar, or a combination thereof.The term "base station" can also refer to a communication module, a modem, or a chip provided in the devices or appliances mentioned above. A base station can also be a mobile switching center, as well as a device that performs the function of a base station in D2D, V2X, machine-to-machine (M2M) communication, a network-side device in a 6G network, a device that performs the function of a base station in future communication systems, or similar systems. The base station may support networks with the same or different access technologies. The embodiments of this disclosure are not limited to the specific technologies and equipment types of the access network devices.

[039] The base station can be a fixed or mobile base station. Petition 870250075840, dated 08 / 27 / 2025, p. 18 / 87 10 / 55 For example, a helicopter or unmanned aerial vehicle can be configured to function as a mobile base station, and one or more cells can move according to the location of the mobile base station. In some other examples, the helicopter or unmanned aerial vehicle can be configured to serve as a communication device with another base station.

[040] The communication equipment involved in wireless communication systems can include not only access network devices and terminal devices, but also core network elements. A core network element can be implemented by a device, i.e., the core network element can be a core network device. It is understandable that the core network device can also be a network device.

[041] The core network elements in embodiments of this disclosure may include network elements that process and forward user signaling and data. For example, core network devices may include core network devices with a mobility and access management (AMF) function, a session management function (SMF), a user plane gateway, a location management function (LMF), etc. The user plane gateway may be a server with mobility management, routing, forwarding, and similar user plane data functions, and is typically on the network side, such as a service gateway (SGW), a packet data network gateway (PGW), or a user plane function (UPF), etc. Obviously, the core network may also include other network elements, which are not listed here.

[042] In some implementations, the network device in the embodiments of this disclosure may refer to the CU or the DU, or the network device may include both the CU and the DU. The gNB may also include the AAU. Petition 870250075840, dated 08 / 27 / 2025, p. 19 / 87 11 / 55

[043] Network devices and terminal devices can be deployed on land, including indoor or outdoor environments, portable or vehicle-mounted, or they can be deployed on water, or they can be deployed on airplanes, balloons, and satellites in the air. The scenarios in which network devices and terminal devices are deployed are not limited to the embodiments of this disclosure.

[044] It should be understood that all or part of the communication device functions in this disclosure may also be implemented by software functions running on hardware or by virtualization functions instantiated on a platform (such as a cloud platform). Non-terrestrial network (NTN)

[045] In related technologies, base stations in cellular communication networks can be built on relatively high ground, such as rooftops and mountaintops, to cover a relatively large area. The radius of a base station's coverage area can range from hundreds of meters to 100 kilometers. The base station's coverage area can depend on the frequency bands. For example, the coverage area of ​​a base station in the low-frequency band (such as 700 MHz) can be relatively large, and the coverage area of ​​a base station in the high-frequency band (24 GHz) can be relatively small. Population density in urban areas or suburbs is relatively high. If such ground-based base stations are used, a relatively large number of terminal devices can be covered within the coverage area of ​​each base station. Therefore, in urban areas or suburbs, the coverage of these ground-based base stations is very efficient.However, even in rural areas with low population density, operators must establish a base station at certain intervals (such as 100 kilometers) to achieve base station coverage. Petition 870250075840, dated 08 / 27 / 2025, page 20 / 87 12 / 55 Therefore, if such ground-based base stations are used in rural areas, there will be problems of low efficiency and high cost. Furthermore, with the continuous development of cellular communication networks and the advancement of technologies such as the Internet of Things, there is a growing demand for coverage in rarely visited areas. For example, cellular communication networks need to monitor the operation of oil pipelines in desert areas and provide communication support for ocean-going cargo ships. However, ground-based base stations cannot support such scenarios.

[046] In response to the above problems, NTN communication emerged. NTN communication can be implemented using satellites or other non-terrestrial communication devices. Therefore, in some embodiments, NTN communication can also be called satellite communication.

[047] Depending on the location where a wireless network device is deployed, NTN communication can operate in curved tube mode or in regenerative mode.

[048] Figure 2A is a schematic diagram illustrating NTN communication in curved tube mode. As shown in Figure 2A, in curved tube mode, the base station is deployed on the ground and the satellite can function as a repeater. For downlink communication, a downlink signal sent by the base station is transmitted to the satellite via a gateway (GW). The downlink signal is then transmitted to the terminal device on the ground via the satellite, which is a special repeater. For uplink communication, an uplink signal sent by the terminal device is transmitted to the gateway on the ground via a special repeater, which is the satellite, and then transmitted to the base station. With a gateway from the main network, the base station can transmit the uplink signal to an external network.

[049] Figure 2B is a schematic diagram that illustrates the Petition 870250075840, dated 08 / 27 / 2025, page 21 / 87 13 / 55 NTN communication in regeneration mode. As shown in Figure 2B, in regeneration mode, the base station is deployed on the satellite. Data is transmitted between the main network element and the base station via the gateway. The terminal device transmits the data directly to the base station on the satellite.

[050] Unlike terrestrial communication systems, the satellite can move continuously along a predetermined orbit. In this case, the coverage area of ​​a cell corresponding to the satellite on the ground can be mobile or fixed. Depending on whether the cell is mobile or fixed, there are two modes of operation of the cell corresponding to the satellite: mobile cell or fixed cell.

[051] For a mobile cell, as the satellite moves, the cell's coverage area also moves on the ground. Figure 3A is a schematic diagram of a mobile cell. As shown in Figure 3A, when the satellite is in position 1, the cell's coverage area is area 1, and when the satellite is in position 2, the cell's coverage area is area 2. As the satellite moves from position 1 to position 2, the coverage area of ​​the cell corresponding to the satellite changes from area 1 to area 2. As shown in Figure 3A, the coverage corresponding to area 1 is different from that corresponding to area 2. When the cell is mobile, the satellite implementation is relatively simple, with the tilt angle of the satellite antenna relative to the ground remaining unchanged. However, the implementation of the terminal device is relatively complex.

[052] For a fixed cell, the cell's coverage area does not move with the satellite. That is, as the satellite moves, the cell's coverage area practically does not change. Figure 3B is a schematic diagram of a fixed cell. When the satellite is in position 1, the cell's coverage area is area 1, and when the satellite is in position 2, the area of Petition 870250075840, dated 08 / 27 / 2025, page 22 / 87 14 / 55 cell coverage is area 2. As shown in Figure 3B, area 1 is practically the same as area 2. When the cell is fixed, satellite implementation is relatively complex, requiring adjustment of the antenna tilt angle relative to the ground according to the satellite's physical location. However, terminal device implementation is relatively simple.

[053] It should be noted that the satellite types and cell types described above are independent of each other. In other words, the types can be combined in any way. For example, there can be four combinations: curved tube mode and mobile cell, curved tube mode and fixed cell, regeneration mode and mobile cell, and regeneration mode and fixed cell. Satellite Switch

[054] Because the satellite can move, even if the terminal device is not moving, the satellite serving the terminal device can change. Taking as an example the combination of curved tube mode and fixed cell, the physical cell ID (PCI) in some communication protocols (such as the 3GPP protocol) remains unchanged. For the terminal device, as a previous satellite moves out and a new satellite moves in, the base station can remain unchanged, and all the settings used by the cell (including PCI) can remain unchanged. In this case, one can consider that the repeater is changed, which does not involve changing the protocol stacks. Therefore, this process can be called switching, but it cannot be considered switching in the strict sense.

[055] Figure 4 is a schematic diagram illustrating a satellite switching process in which the PCI remains unchanged. Before the satellite switching moment on the time axis, the terminal device (represented by UE in Figure 4) is in communication with a first Petition 870250075840, dated 08 / 27 / 2025, page 23 / 87 15 / 55 satellite, and the PCI of the cell corresponding to the first satellite is a first PCI. After the satellite change, the base station replaces the first satellite with a second satellite, and the terminal device begins transmitting data through the second satellite. The PCI of the cell corresponding to the second satellite remains unchanged, i.e., the first PCI. Although the satellite has changed, since all the base station settings remain unchanged, all the wireless configuration parameters of the terminal device can remain unchanged. Information on historical events

[056] In related technologies, the NTN cell can inform the terminal device about satellite-related position information by means of ephemeris information. Based on the ephemeris information, the terminal device can derive the satellite's current location. Ephemeris information can be transmitted by means of a system information broadcast (SIB) 19.

[057] In some embodiments, ephemeris information may include one or more of the following: a reference time, a change parameter, and an effective time period. As shown in Figure 5, the ephemeris information obtained by the terminal device includes the reference time T1, the effective time period of the ephemeris information (T2-T1), and the change parameter. Based on this information, the terminal device can calculate the satellite's location at any time during the time period from T1 to T2. For example, for a time T3, the terminal device can determine the satellite's location at time T3 based on the satellite's location at the reference time T1, the duration of the time period from T1 to T3 (T3-T1), and the change parameter.

[058] It is observed that the network device can provide the Petition 870250075840, dated 08 / 27 / 2025, page 24 / 87 16 / 55 ephemeris information is provided to the terminal device before or after the reference time. Additionally, before the current ephemeris information becomes invalid, the network device can provide updated ephemeris information to the terminal device.

[059] Figure 6 is a schematic diagram illustrating the provision of new ephemeris information by the network device before the current ephemeris information becomes invalid. For ease of distinction, the ephemeris information before the update is called old ephemeris information, and the updated ephemeris information is called new ephemeris information. As shown in Figure 6, the old ephemeris information becomes invalid at time T2. Before time T2, the network device can provide the new ephemeris information to the terminal device. The reference time for the new ephemeris information is T1'. Therefore, during the period from T1' to T2', the terminal device has two sets of ephemeris information available.In cases where the terminal device calculates the physical location of a satellite using ephemeris information, although the physical locations of the same satellite calculated based on two ephemeris data sets may not be identical, the physical locations within a given range of accuracy can be considered valid and equivalent to each other. Therefore, the terminal device can arbitrarily choose which ephemeris data set to use.

[060] Related technologies have not yet proposed how the terminal device responds to satellite switching. For example, before and after a satellite change, the qualities of the wireless signals detected by the terminal devices are different, and related technologies have not yet proposed how to handle the difference in wireless signal qualities. Alternatively, in the case where the satellite is switched, the technologies Petition 870250075840, dated 08 / 27 / 2025, page 25 / 87 17 / 55 related studies have not yet proposed how the terminal device uses ephemeris information. Taking as an example the use of ephemeris information after a satellite change, the problems that this disclosure aims to solve are analyzed below.

[061] As shown in Figure 7, an effective moment of ephemeris information from the replaced satellite (hereinafter referred to as the new satellite) can have three cases, each of which has many problems. Case 1: The effective time for the ephemeris information of the new satellite is BEFORE THE TIME OF THE SATELLITE CHANGE.

[062] In this case, the terminal device may have two effective ephemeris information sets for a period of time. For example, during this period, the ephemeris of the new satellite becomes effective, but the satellite does not change. During this period, since the satellite does not change, the terminal device must use the ephemeris information of the satellite prior to the change (hereinafter referred to as the old satellite). However, according to related technologies, the terminal device may use the ephemeris information of either the old or the new satellite. Although, for the solution where the PCI remains unchanged, the wireless configuration of the cell and the wireless parameters of the terminal device remain unchanged during the satellite change, there are significant differences between the ephemeris information of the new satellite and that of the old satellite.Therefore, the arbitrary choice of ephemeris information can result in the terminal device using the ephemeris information from the new satellite before the satellite change. In other words, the terminal device may use ephemeris information that does not correspond to that of the current satellite, resulting in communication anomalies. Case 2: The effective moment of the new satellite's ephemeris is equal to the MOMENT OF THE SATELLITE EXCHANGE.

[063] In this case, the terminal device can immediately use the ephemeris information from the new satellite after the moment Petition 870250075840, dated 08 / 27 / 2025, page 26 / 87 18 / 55 of the satellite exchange. However, this solution imposes significant restrictions on the provision of ephemeris information. For example, the effective time of the ephemeris information from the new satellite must be forcibly aligned with the time of the satellite exchange by the network; otherwise, the solution cannot be implemented. However, aligning the effective time of the ephemeris information from the new satellite with the time of the satellite exchange complicates the implementation of the network device.

[064] Case 3: The effective time of the new satellite's ephemeris is later than the time of the satellite change.

[065] In this case, after the satellite change, the terminal device must wait for the effective moment of the new satellite's ephemeris information before using the new satellite's ephemeris information. That is, in Case 3, there is no ephemeris information available to the terminal device between the moment of the satellite change and the effective moment of the new satellite's ephemeris information.

[066] Figure 8 is a schematic flowchart of a communication method according to some embodiments of the present disclosure, used to solve the problems above. The method shown in Figure 8 can be executed by a terminal device. The method shown in Figure 8 can include the operation (S810).

[067] In operation (S810), the terminal device performs a first operation according to a first moment.

[068] The first moment may be a moment of exchange of a satellite corresponding to a first cell for the terminal device. Before the first moment, the satellite corresponding to the first cell is not changed (i.e., the old satellite). After the first moment, the satellite corresponding to the first cell is changed (i.e., the new satellite). The PCI of the first cell may remain unchanged before and after the satellite exchange. The first cell Petition 870250075840, dated 08 / 27 / 2025, page 27 / 87 19 / 55 can be a server cell (or current cell) for the terminal device.

[069] The first operation may include a second operation and / or a third operation. The second operation may be an operation performed by the terminal device after the terminal device begins using the ephemeris information from the new satellite. The third operation may be an operation performed by the terminal device in response to the satellite change.

[070] When the terminal device performs the second operation according to the first moment, based on the moment of the satellite change, the terminal device can determine the moment from which the terminal device starts using the ephemeris information of the new satellite to perform the second operation. That is, the moment when the ephemeris information of the new satellite is used may not be the same as the effective moment of the ephemeris information of the new satellite. Therefore, based on the present disclosure, the ephemeris information can be used more appropriately to the real situation, thus avoiding the problems caused by relating only the moment from which the terminal device starts using the ephemeris information of the new satellite with the effective moment.For example, for Case 1, as shown in Figure 7, the terminal device can determine how to use the ephemeris information from the new satellite based on the first moment, thus avoiding the use of the new satellite's ephemeris information without a change to the satellite.

[071] Before the satellite switchover, the network device can provide the terminal device with the ephemeris information of the new satellite. The effective time of the new satellite's ephemeris information may be earlier than the satellite switchover. In this case, the terminal device can start using the new satellite's ephemeris information as early as possible. Petition 870250075840, dated 08 / 27 / 2025, page 28 / 87 20 / 55 is possible, according to the first moment (for example, starting to use the ephemeris information from the new satellite at the first moment), thus avoiding the situation where there is no ephemeris information available to the terminal device after the satellite change. For example, for Case 2 or Case 3, as shown in Figure 7, the ephemeris information from the new satellite can be transmitted before the first moment and take effect before the first moment (i.e., enhanced to be Case 1). At the first moment, the terminal device can start using the ephemeris information from the new satellite. On the one hand, this solution can avoid the need to align the moments in Case 2, thus simplifying the implementation of the communication process.On the other hand, the terminal device can use the ephemeris information from the new satellite as quickly as possible after the satellite switch, thus reducing the duration of the communication interruption.

[072] It should be noted that the first operation may be an operation that needs to be performed by any terminal device based on ephemeris information. For example, the first operation may include one or more of the following operations: calculating the satellite location, calculating the time when an uplink signal is transmitted to the satellite, transmitting the uplink signal, and calculating a time advance (TA). The uplink signal may include, for example, a random access preamble. That is, the first operation may also include random access. The use of ephemeris information to perform the first operation by the terminal device can be understood as the fact that the terminal device can perform the first operation using ephemeris information or based on ephemeris information.

[073] In response to the satellite change, the terminal device may perform a third operation. The third operation may be related to ephemeris information. It should be understood that the third operation is Petition 870250075840, dated 08 / 27 / 2025, page 29 / 87 21 / 55 is beneficial for satellite switching and / or for communication after switching. For example, performing the third operation can ensure the normal progress of satellite switching. Alternatively, through the third operation, communication anomalies after satellite switching can be avoided.

[074] The second and third operations are described below, respectively. The moment when the terminal device begins to perform the second operation based on the ephemeris information of the new satellite can be called the moment of use. In some embodiments, the moment of use may be the same as the first moment. In other words, the terminal device may begin to use the ephemeris information of the new satellite at the moment of satellite switching. That is, before the moment of satellite switching, the terminal device does not use the ephemeris information of the new satellite; and after the moment of satellite switching, the terminal device uses the ephemeris information of the new satellite. In this way, it is possible to avoid using the ephemeris information of the new satellite before the switch.

[075] In some embodiments, the moment when the terminal device stops using the ephemeris information from the old satellite may be the same as the first moment. In other words, before the satellite changeover, the terminal device uses the ephemeris information from the old satellite; and after the satellite changeover, the terminal device does not use the ephemeris information from the old satellite. In this case, even if the effective time of the ephemeris information from the old satellite does not expire, the terminal device may stop using the ephemeris information from the old satellite at the moment of the satellite changeover, thus preventing the incorrect use of the ephemeris information from the old satellite after the changeover from the old satellite to the new satellite.

[076] In some embodiments, the method shown in Figure 8 can be executed by a network device. The method shown in Petition 870250075840, dated 08 / 27 / 2025, page 30 / 87 22 / 55 Figure 8 may include operations (S802) and (S804).

[077] In (S802), the network device determines the first moment.

[078] In (S804), the network device configures one or more of the following information according to the first moment: the ephemeris information of the new satellite and the first operation. In some embodiments, the method shown in Figure 8 may also include operation (S805). In (S805), the network device transmits the first ephemeris information to the terminal device.

[079] The terminal device can determine whether the first ephemeris information received corresponds to the new satellite. In some embodiments, the terminal device can determine whether the first ephemeris information corresponds to the new satellite based on an indication from the network device. The indication of whether the first ephemeris information corresponds to the new satellite can be an explicit or implicit indication, which are illustrated below.

[080] In response to the indication being an explicit indication, the network device may transmit the first indication information to the terminal device. The first indication information may be configured to indicate whether the first ephemeris information corresponds to the new satellite.

[081] The method by which the first indication information is provided is not limited to the present disclosure. For example, the first indication information may belong to the first event information. Alternatively, the first indication information and the first ephemeris information may be carried in different messages.

[082] In some embodiments, the first indication information may be carried in a first bit. In other words, the Petition 870250075840, dated 08 / 27 / 2025, p. 31 / 87 23 / 55 The first indication information can be represented by a bit. For example, the first indication information can be represented by a bit in the first ephemeris information. In some embodiments, when the value of the first bit is 0, the first ephemeris information does not correspond to the new satellite, or the first ephemeris information corresponds to the old satellite; and when the value of the first bit is 1, the first ephemeris information corresponds to the new satellite, or the first ephemeris information does not correspond to the old satellite. In some other embodiments, when the value of the first bit is 1, the first ephemeris information does not correspond to the new satellite, or the first ephemeris information corresponds to the old satellite; and when the value of the first bit is 0, the first ephemeris information corresponds to the new satellite, or the first ephemeris information does not correspond to the old satellite.

[083] In some embodiments, the first indication information can be carried in a first parameter. The first parameter can be a Boolean parameter. In other words, the first indication information can be represented by the Boolean parameter. For example, the first parameter can be a parameter in the first ephemeris information. A value of the first parameter can be true or false. In some embodiments, when the value of the first parameter is true, the first ephemeris information does not correspond to the new satellite, or the first ephemeris information corresponds to the old satellite; and when the value of the first parameter is false, the first ephemeris information corresponds to the new satellite, or the first ephemeris information does not correspond to the old satellite.In some other embodiments, when the value of the first parameter is false, the first ephemeris information does not correspond to the new satellite, or the first ephemeris information corresponds to the old satellite; and when the value of the first... Petition 870250075840, dated 08 / 27 / 2025, p. 32 / 87 If the 24 / 55 parameter is true, the first ephemeris information corresponds to the new satellite, or the first ephemeris information does not correspond to the old satellite.

[084] In some embodiments, the first indication information may be optional, i.e., in a first message configured to carry the first indication information, the first indication information may or may not be present. For example, in response to the terminal device not receiving the indication information at the first moment, the first message may not include the first indication information; and / or, in response to the terminal device receiving the indication information at the first moment, the first message may include the first indication information. Alternatively, in response to the terminal device receiving the indication information at the first moment, the terminal device may receive the first indication information; and / or, in response to the terminal device not receiving the indication information at the first moment, the terminal device may not receive the first indication information.

[085] It should be noted that the message carrying the indication information at the first moment may be the first message or a second message different from the first message. The first or second message may include, for example, broadcast messages and / or radio resource control (RRC) messages. Broadcast messages may be, for example, SIB19 messages. Broadcast messages may be used to indicate the above information to the terminal device in idle or connected state. Dedicated RRC messages may be used to indicate the above information to the terminal device in connected state.

[086] The method for explicitly indicating whether the first ephemeris information corresponds to the new satellite is illustrated above. The Petition 870250075840, dated 08 / 27 / 2025, page 33 / 87 The 25 / 55 implicit indication method is illustrated below.

[087] In some embodiments, the effective moment of the first ephemeris information may be a second moment. Whether or not the first ephemeris information corresponds to the new satellite can be determined based on the second moment.

[088] Figure 9 is a schematic diagram of the implicit indication of whether the first ephemeris information corresponds to the new satellite. As shown in Figure 9, when the difference between the second moment and the first moment is less than or equal to a first time limit, the first ephemeris information may correspond to the new satellite; and / or, when the difference between the second moment and the first moment is greater than the first time threshold, the first ephemeris information may correspond to the old satellite. In this case, the second moment may be earlier than the first moment.

[089] The method of determining the first time limit is not specifically limited in this disclosure. For example, the first time limit may be determined or indicated by one or more of the following: a protocol provision, an RRC message, a medium access control element (MAC CE), and downlink control information (DCI). For example, the first time limit may be indicated by means of a broadcast message. In response to acquiring the first time limit by means of the RRC message, the terminal device may acquire the first time limit by means of the RRC messages of the current cell (such as the first cell) or by means of the RRC messages of other cells. The broadcast message may include a SIB message. The RRC message may be a dedicated RRC message.

[090] In some embodiments, the network device may indicate that a satellite corresponding to a first neighboring cell is Petition 870250075840, dated 08 / 27 / 2025, page 34 / 87 26 / 55 will make the satellite corresponding to the first cell. Since the satellite's orbit is predictable, it is possible that the satellite corresponding to the neighboring cell will become the satellite corresponding to the first cell. Based on the second indication information, the terminal device can directly determine the ephemeris information of the new satellite using the ephemeris information of the neighboring cell. Therefore, the network device does not need to inform the terminal device about the ephemeris information of the new satellite yet, thus reducing the consumption of communication resources.

[091] The network device may indicate, explicitly or implicitly, that the satellite corresponding to the first neighboring cell will become the new satellite corresponding to the first cell.

[092] Taking explicit indication as an example, the network device can transmit the second indication information to the terminal device. The second indication information can be used to indicate that the satellite corresponding to the first neighboring cell of the terminal device will become the satellite corresponding to the first cell. In other words, the second indication information can indicate that, at first, the satellite corresponding to the first cell will become the satellite corresponding to the first neighboring cell.

[093] The second indication information can be indicated by a boolean variable, a second bit and a newly added parameter, etc.

[094] For example, the second indication information can be indicated by a true or false Boolean variable. In some embodiments, when the second indication information is true, the satellite corresponding to the first neighboring cell will become the satellite corresponding to the first cell; and when the second indication information is false, the satellite corresponding to the first neighboring cell will not become the satellite corresponding to the first cell. In some other embodiments of Petition 870250075840, dated 08 / 27 / 2025, page 35 / 87 27 / 55 implementation, when the second indication information is false, the satellite corresponding to the first neighboring cell will become the satellite corresponding to the first cell; and when the second indication information is true, the satellite corresponding to the first neighboring cell will not become the satellite corresponding to the first cell.

[095] As another example, the second indication information can be indicated by the second bit, that is, a bit. The second bit can be evaluated as 0 or 1. In some embodiments, when the second indication information is 0, the satellite corresponding to the first neighboring cell will become the satellite corresponding to the first cell; and when the second indication information is 1, the satellite corresponding to the first neighboring cell will not become the satellite corresponding to the first cell. In some other embodiments, when the second indication information is 1, the satellite corresponding to the first neighboring cell will become the satellite corresponding to the first cell; and when the second indication information is 0, the satellite corresponding to the first neighboring cell will not become the satellite corresponding to the first cell.

[096] In some embodiments, the second indication information may be carried in the ephemeris information of the satellite corresponding to the first neighboring cell. In response to the second indication information existing in the ephemeris information of the satellite corresponding to the first neighboring cell, the satellite corresponding to the first neighboring cell will become the new satellite corresponding to the first cell. In response to the second indication information not existing in the ephemeris information of the satellite corresponding to the first neighboring cell, the satellite corresponding to the first neighboring cell will not become the new satellite corresponding to the first cell.

[097] Ephemeris information for the current cell and the neighboring cell can be indicated by means of a list of information Petition 870250075840, dated 08 / 27 / 2025, page 36 / 87 28 / 55 ephemeris. That is, the ephemeris information list can include one or more ephemeris information. One or more ephemeris information can correspond to the current cell and / or the neighboring cell. Figure 10 is an example diagram of the ephemeris information list. The ephemeris information list, as shown in Figure 10, includes: the ephemeris information of the current cell and the ephemeris information of three neighboring cells. As shown in Figure 10, the second explicitly indicated information can be added to the ephemeris information of the first neighboring cell, so that the network device can inform the terminal device that “from the moment of the satellite change, the ephemeris information of the first neighboring cell becomes the ephemeris information of the current cell”.

[098] Taking implicit indication as an example, the ephemeris information of the first neighboring cell may belong to the ephemeris information list. The ephemeris information list may include: ephemeris information of a server cell of the terminal device and / or the ephemeris information of one or more neighboring cells of the terminal device. The ephemeris information of the first neighboring cell may occupy a first position in the ephemeris information list. The first position may be used to indicate whether the satellite corresponding to the first neighboring cell will become the satellite corresponding to the first cell. In this way, the network device may not transmit additional indication information, thus avoiding resource occupancy due to the additional transmission of indication information.

[099] In some embodiments, when the first position satisfies a first condition, the satellite corresponding to the first neighboring cell will become the satellite corresponding to the first cell (i.e., the new satellite). For example, the first condition might include: the first position Petition 870250075840, dated 08 / 27 / 2025, page 37 / 87 29 / 55 is a position of the first neighboring cell. That is, when the ephemeris information corresponding to the first neighboring cell is the ephemeris information of a neighboring cell that occupies the first position in the ephemeris information list, the ephemeris information corresponding to the first neighboring cell will become the ephemeris information of the new satellite. Alternatively, the first condition may include: the first position is an Nth position in the ephemeris information list of one or more neighboring cells. That is, the first position is a position of an Nth neighboring cell. That is, when the ephemeris information corresponding to the first neighboring cell is the ephemeris information of an Nth neighboring cell in the ephemeris information list, the ephemeris information corresponding to the first neighboring cell will become the ephemeris information of the new satellite, where N can be a positive integer.N can be provided by protocols or configured by the network device. Taking the ephemeris information shown in Figure 10 as an example, when N = 1, the satellite corresponding to the first neighboring cell will become the satellite corresponding to the first cell. When N = 2, the satellite corresponding to the second neighboring cell will become the satellite corresponding to the first cell. When N = 3, the satellite corresponding to the third neighboring cell will become the satellite corresponding to the first cell.

[0100] The transmission delay of the new satellite and the old satellite may be different. Therefore, for terminal devices, instability may occur at the subframe boundary (e.g., downlink subframe boundary). That is, for the terminal device, the boundaries of frames and / or subframes with the same numbering and corresponding to the new satellite and the old satellite may not coincide. In this disclosure, a fourth moment associated with the ephemeris information of the new satellite can be determined based on the following subframe boundary: the subframe boundary before the switch. Petition 870250075840, dated 08 / 27 / 2025, p. 38 / 87 30 / 55 satellite; or the subframe limit after the satellite change. Therefore, this disclosure clarifies the subframe limit, thus addressing the problem of fourth-moment ambiguity caused by the satellite change.

[0101] The network device can indicate, by means of the boundary indication information, that the fourth moment is determined based on the subframe boundary of the new satellite or the subframe boundary of the old satellite. The boundary indication information can be carried in one or more of the following messages: an RRC message, a DCI, and a MAC CE. The boundary indication information can be configured in one or more of the following ways: a boolean, a binary symbol (a bit), or an enumeration variable.

[0102] The fourth moment may include one or more of the following moments: the moment when the ephemeris information from the new satellite becomes invalid and the moment when the ephemeris information from the new satellite becomes effective.

[0103] To facilitate understanding, the determination of the fourth moment is explained in Figure 11 below. In the example shown in Figure 11, the terminal device receives ephemeris information from the new satellite. The effective moment of the ephemeris information from the new satellite is frame no. 583, subframe no. 4, and the effective duration of the ephemeris information is 10.24 seconds. When the terminal device uses the ephemeris information, it can calculate a time advance (TA) of the uplink transmission using the moment corresponding to frame number 583 and subframe number 4 of the old satellite as the effective moment. On the other hand, with the effective duration of 10.24 seconds of the ephemeris, after one cycle of system frame numbers (SFNs), and when the frame number is 583 and the subframe number is 4, the ephemeris information becomes invalid. However, due to the different physical locations of the two satellites, Petition 870250075840, dated 08 / 27 / 2025, p. 39 / 87 31 / 55 from the perspective of the terminal device, the subframe boundary jitter occurs. Regarding the subframe boundary in the case where the satellite corresponding to the first cell is the old satellite, an invalid moment of the ephemeris information obtained by adding 10.24 seconds to an effective moment of the ephemeris information is represented by the solid gray line, as shown in Figure 11. However, regarding the subframe boundary in the case where the satellite corresponding to the first cell is the new satellite, when the effective moment of the ephemeris information is determined by frame #583, subframe #4, then the invalid moment of the ephemeris information must also be determined by frame #583, subframe #4, that is, the moment as shown by the dashed gray line in Figure 11.When the invalidity moments obtained by the two calculation methods are different, the protocol may specify that the terminal device uses the solid gray line as the invalidity moment for the ephemeris information, or specify that the terminal device uses the dashed gray line as the invalidity moment for the ephemeris information, or allow the network device to select which moment should be used as the invalidity moment for the ephemeris information.

[0104] The third operation is described below.

[0105] The third operation may be associated with one or more of the following: a power margin report (PHR), a time advance (TA), a power adjustment value, a random access, a K offset, and a radio link monitoring (RLM).

[0106] It should be noted that a moment of execution of the third operation may be associated with the first moment. For example, the moment of execution of the third operation may be the first moment or later than the first moment. That is, the terminal device may execute the third operation when the satellite changes or after the satellite change. Alternatively, Petition 870250075840, dated 08 / 27 / 2025, page 40 / 87 32 / 55 The timing of the third operation may precede the first. In other words, the terminal device may execute the third operation before the satellite change.

[0107] In some embodiments, the third operation includes one or more of the following: before the first moment, when the terminal device triggers a first PHR, canceling the triggering of the first PHR; triggering a second PHR; triggering a TA report; resetting the power adjustment value; performing some or all of the operations performed by the terminal device after the timeout of a time advance timer (TAT); clearing a hybrid auto-repeat request (HARQ) buffer; acquiring an uplink synchronization via random access; when the terminal device initiates random access before the first moment and continues random access after the first moment, resetting a first counter associated with random access and incrementing the first counter by one counting unit or keeping the first counter unchanged;When the terminal device initiates random access before the first moment and continues random access after the first moment, performing downlink synchronization in response to downlink desynchronization; and / or reselecting a random access resource according to the changed satellite signal quality; using the K offset configured by the changed satellite or the K offset with a value of 0; resetting a second counter associated with the RLM; and stopping a first timer associated with the RLM. Each of the above operations is described below.

[0108] In some embodiments, before the first moment when the terminal device activates the first PHR, the third operation may include canceling the activation of the first PHR. That is, when the terminal device activates the PHR before the satellite switching moment, the terminal device may cancel the PHR activation. It should be Petition 870250075840, dated 08 / 27 / 2025, page 41 / 87 33 / 55 Note that the firing of the first PHR can be canceled immediately or after it.

[0109] The PHR is triggered because, compared to the path loss that occurred in the last PHR transmission, a change in the path loss value exceeds a threshold. After the satellite change, the path loss value is no longer associated with the previous path loss. In this case, the previously triggered path loss no longer has a reference value for the network device. Therefore, canceling the first PHR trigger can reduce unnecessary communication processes and simplify communication operations.

[0110] In some embodiments, the third operation may include firing a second PHR in response to a satellite change. For example, after the moment of the satellite change or after the satellite change, the terminal device may fire the PHR again.

[0111] After the satellite change, the path loss measurement by the terminal device can be considered a newly initiated measurement. Therefore, when the second PHR is triggered after the satellite change and is used as a reference for the path loss measurement, a reference can be provided to a network device scheduling algorithm.

[0112] In some embodiments, the third operation may include triggering the TA report. For example, after the satellite change or satellite switching moment, the terminal device may trigger the TA report.

[0113] The satellite change causes an original TA value of the terminal device to become invalid. The original TA value no longer has a reference value for the network device scheduling. Therefore, the TA value reported by the terminal device in this disclosure has a reference value for the network device scheduling algorithm. Petition 870250075840, dated 08 / 27 / 2025, page 42 / 87 34 / 55

[0114] It should be noted that the TA report triggered in the third operation can be performed using any uplink resource, which is not limited in this disclosure. For example, resources for the TA report may include one or more of the following: uplink resources obtained by the terminal device through random access and uplink resources obtained by the terminal device by other means. Uplink resources obtained by other means may include, for example, resources allocated to the terminal device by the network device using dynamic scheduling or semi-static scheduling.

[0115] In some embodiments, the third operation may include resetting the power adjustment value to zero. For example, at the time of or after a satellite change, the terminal device may reset it to zero. The power adjustment value may be recorded by the terminal device and is associated with the terminal device's transmission power.

[0116] The power adjustment value can be an accumulated value. For example, the network device can adjust the terminal device's power using an accumulated mode. That is, the terminal device can determine the uplink transmission power according to the measured path loss and the power adjustment values ​​recorded by the terminal device in an accumulated manner. In some embodiments, the power adjustment values ​​can be, for example, associated with a transmission power control (TPC). For example, the network device can continuously transmit the TPC to the terminal device to inform it about the adjustment of the recorded power adjustment values. In this case, the power adjustment values ​​can include an accumulated value of the TPC.

[0117] In response to a satellite change, the power adjustment values ​​recorded by the terminal device become invalid. The technical solution proposed in this disclosure is to reset the adjustment value of Petition 870250075840, dated 08 / 27 / 2025, page 43 / 87 35 / 55 power to zero, can obtain an accurate record of the power adjustment value after the satellite change, thus allowing the terminal device to determine the appropriate uplink transmission power for the new satellite.

[0118] In some embodiments, the third operation may include some or all of the operations that need to be performed by the terminal device after the TAT timeout. That is, satellite switching may be equivalent to the TAT timeout to some extent. The third operation may include, for example, clearing the HARQ buffer and / or achieving uplink synchronization via random access.

[0119] When the terminal device initiates random access before the first moment and needs to continue random access after the first moment, the third operation can be associated with the first counter. The first counter can be associated with random access. For example, the first counter can include a counter to count the number of random access times and / or a counter to count the number of random access power ramps. That is, the first counter can be used to count: the number of random accesses and / or the number of random access power ramps.

[0120] Regarding the first counter, the third operation may include: resetting the first counter and incrementing the first counter by one counting unit or leaving the first counter unchanged. That is, for a first random access after the satellite change, the first counter may start counting from zero and be incremented by one counting unit or remain unchanged. The counting unit may be one or more minimum counting units that can be counted by the counter.

[0121] It should be noted that when the first counter includes a plurality of counters, the third operations corresponding to the plurality of counters may be different or the same. For example, when the first Petition 870250075840, dated 08 / 27 / 2025, page 44 / 87 The 36 / 55 counter includes a counter used to count the number of random accesses and a counter used to count the number of power ramps of the random access. For the first random access after the satellite change, the first counter can count using any of modes 1 through 3, as shown in Table 1. Table 1 Counter for counting the number of random accesses Counter for counting the number of random access power ramps Mode 1 Starting at 0 Starting at 0 Mode 2 Incremented by 1 Incremented by 1 Mode 3 Incremented by 1 Remaining unchanged

[0122] As shown in Table 1, when Mode 1 is used, the terminal device resets both counters and restarts the count from 0. When Mode 2 is used, the terminal device can increment the counter for the random access count by 1, and also increment the counter for the random access power ramp count by 1. When Mode 3 is used, the terminal device can increment the counter for the random access count by 1, and keep the counter for the random access power ramp count unchanged.

[0123] In some embodiments, when the terminal device initiates random access before the first moment and continues random access after the first moment, the third operation may include: performing downlink synchronization in response to downlink asynchronization; and / or reselecting a random access resource based on the altered satellite signal quality.

[0124] When the terminal device is performing random access before the satellite change and continues random access after the satellite change, the terminal device needs to ensure downlink synchronization before the first random access after the change. Petition 870250075840, dated 08 / 27 / 2025, page 45 / 87 37 / 55 satellite. In the event of downlink asynchronous activity at this time, this disclosure proposes that the terminal device must perform downlink synchronization before performing random access.

[0125] When the terminal device is performing random access before the satellite switching time and the random access feature selected by the terminal device is associated with signal quality, at the time of satellite switching or after satellite switching, the terminal device may reselect the random access feature based on signal quality after satellite switching to continue random access. Signal quality may include, for example, a received reference signal strength (RSRP). As an example, in a coverage enhancement scenario, different RSRP values ​​correspond to different sets of random access features, or different RSRPs may correspond to supplemental uplink (SUL) carriers or normal carriers.

[0126] It should be noted that the continuation of random access described in this disclosure may refer to the continuation of random access by the MAC layer of the terminal device, which may not involve RRC, i.e., the continuation of random access does not refer to random access reactivated by RRC.

[0127] In some embodiments, the third operation may include an operation that indicates one or more of the following: after or at the first moment, the terminal device may use the K offset configured for the changed satellite, or the terminal device uses the K offset with a value of 0.

[0128] In some embodiments, at the moment, before or after the satellite change, an internal MAC layer of the terminal device indicates to a physical layer (PHY) that the offset K is 0. After the moment Petition 870250075840, dated 08 / 27 / 2025, page 46 / 87 38 / 55 before or after the satellite change, the terminal device can use the K-offset with a value of 0. In some other embodiments, before the satellite change, the terminal device receives the K-offset with a new value indicated by the network device. Additionally, the network device can simultaneously indicate that the new K-offset value will only be used at the time of the satellite change or after the satellite change. Furthermore, the terminal device's MAC layer indicates the new K-offset to the PHY layer. After the satellite change, the terminal device can use the K-offset configured for the new satellite by the network device.

[0129] In some embodiments, when the terminal device receives the offset K indicated by the network device, the terminal device may start using the offset K after the first moment. When the terminal device does not receive the offset K indicated by the network device, the terminal device may use the offset K with a value of 0.

[0130] In some embodiments, both the second counter and the first timer can be associated with the RLM. The third operation may include: resetting the second counter; and / or stopping the first timer.

[0131] The second counter may include, for example, a counter to count the number of times a single wireless signal measurement result was greater than or equal to a first limit, and / or a counter to count the number of times a single wireless signal measurement result was less than a second limit. The count value of the counter to count the number of times a single wireless signal measurement result was greater than or equal to the first limit may be compared with (N310), and the count value of the counter to count the number of times a result Petition 870250075840, dated 08 / 27 / 2025, page 47 / 87 39 / 55 from a single measurement of the wireless signal was lower than the second limit, which can be compared with (N311).

[0132] The first timer may be a timer used to determine a radio link fault (RLF). For example, the first timer may include a timer (T310).

[0133] To facilitate understanding of the second counter and the first timer, an example is illustrated below with reference to Figure 12.

[0134] As shown in Figure 12, during an RLM process, the terminal device's RRC continuously receives a wireless signal quality indication from the PHY layer and determines whether an RLF occurs in the current server cell based on the wireless signal quality indication. The wireless signal quality indication may include a first indication and a second indication. The first indication may include, for example, a synchronization indication, and the second indication may include, for example, a desynchronization indication. The first indication may indicate that the result of a single wireless signal measurement is greater than or equal to the first threshold. The second indication may indicate that the result of a single wireless signal measurement is less than the second threshold. When the number of times the RRC continuously receives the second indication exceeds (N310), the timer (T310) may be started.During the execution of (T310), when the number of times the RRC continuously receives the first indication.

[0135] In the flow shown in Figure 12, the second counter can be used to: count the number of second indications received continuously to determine if the number is greater than (N310); and / or the number of first indications received continuously to determine if the number is greater than (N311). The first timer can include (T310). Petition 870250075840, dated 08 / 27 / 2025, page 48 / 87 40 / 55

[0136] Since the wireless signal quality before the satellite change does not correlate with the wireless signal quality after the satellite change, resetting the second counter and / or stopping the first timer can prevent the impact on the RLM process caused by the old satellite, thus allowing the RLM process to be more accurate.

[0137] It should be noted that whether or not the third operation is executed by the terminal device may be determined by the provision of protocols and / or the configuration of the network device. Continuing with Figure 8, the operation (S804) may include: the configuration, by the network device, of the third operation based on the first moment.

[0138] In some embodiments, whether or not the third operation is performed can be configured by the network device. The network device can indicate whether the third operation should be performed by means of the first configuration information. This disclosure does not limit a transmission time or a reception time of the first configuration information. For example, the transmission time or the reception time may be earlier, later, or equal to the first time. The transmission time and / or the reception time above may be provided by protocols. Furthermore, this disclosure does not limit the messages that carry the first configuration information. For example, the first configuration information may be carried in one or more of the following messages: an RRC message, a CE MAC message, DCI, and the like.

[0139] In some embodiments, the initial configuration information is used to configure whether the terminal device performs one or more of the following operations: before the first moment, when the terminal device triggers a first PHR, cancel the triggering of the first PHR; trigger a second PHR; trigger a TA report; reset the value of Petition 870250075840, dated 08 / 27 / 2025, page 49 / 87 41 / 55 power adjustment; some or all operations performed by the terminal device after a TAT timeout; clearing a HARQ buffer; acquiring an uplink synchronization via random access; when the terminal device initiates random access before the first moment and continues random access after the first moment, resetting the first counter associated with random access and incrementing the first counter by one count unit or keeping the first counter unchanged; when the terminal device initiates random access before the first moment and continues random access after the first moment, performing a downlink synchronization in response to downlink desynchronization; and / or reselecting a random access resource according to the signal quality of the changed satellite; using the K offset configured by the changed satellite or the K offset with a value of 0; resetting the second counter associated with the RLM;and stopping the first timer associated with the RLM. Each of the above operations is described below.

[0140] In some embodiments, the network device may indicate the first moment to the terminal device. For example, the network device may transmit a third indication piece of information to the terminal device. The third indication piece of information may be used to indicate the first moment.

[0141] In some embodiments, the first moment can be represented by identifying a unit of time and / or absolute time.

[0142] The time unit may include one or more of the following: a radio frame, a subframe, a time interval, and an orthogonal frequency division multiplexing (OFDM) symbol. The time unit identifier may be, for example, a number, ID, or similar for the time unit. That is, the first moment may be represented by a Petition 870250075840, dated 08 / 27 / 2025, page 50 / 87 42 / 55 or more of the following: a radio frame number, a subframe number, a time interval number, and an OFDM symbol number. In some implementations, the first moment may be a moment that matches the time unit identification indicated by the third indication piece in the near future. For example, the third indication piece may indicate the first moment in the form of a frame number + a subframe number. After receiving the third indication piece, the terminal device may consider a moment that matches a frame number + a subframe number in the near future as the first moment.

[0143] Absolute time can be expressed by one or more of the following: years, months, days, hours, minutes, seconds, milliseconds, and microseconds. For example, the first moment can be represented by 16:58:34:304 on June 2, 2023.

[0144] It should be noted that this disclosure does not limit the messages that carry the third indication information. For example, the third indication information may be carried in one or more of the following messages: an RRC message, a MAC CE message, and a DCI message. Alternatively, the third indication information may be carried in a broadcast message.

[0145] The embodiments of the method of this disclosure are described in detail above. The embodiments of the apparatus of this disclosure are described in detail below. It should be understood that the description of the embodiments of the method corresponds to the description of the embodiments of the apparatus and, therefore, for parts that are not described in detail, reference may be made to the embodiments of the method above.

[0146] Figure 13 is a schematic diagram illustrating the structure of a terminal device (1300) according to some forms of Petition 870250075840, dated 08 / 27 / 2025, page 51 / 87 43 / 55 realization of this disclosure. The terminal device (1300) includes an execution unit (1310).

[0147] The execution unit (1310) is configured to perform a first operation according to a first moment. The first moment refers to a moment of switching from a satellite corresponding to a first cell to the terminal device, and the first operation includes one or more of the following operations: a second operation performed by the terminal device after the terminal device starts using the ephemeris information from a changed satellite; and a third operation performed by the terminal device in response to the switching of the satellite corresponding to the first cell.

[0148] In some embodiments, the terminal device starts using a moment in the altered satellite ephemeris information to perform the second operation at the first moment.

[0149] In some embodiments, the terminal device stops using the satellite ephemeris information before switching to the satellite in order to perform the second operation at the first moment.

[0150] In some embodiments, the terminal device is further configured to receive the first ephemeris information and determine whether the first ephemeris information corresponds to the altered satellite.

[0151] In some embodiments, the terminal device is further configured to receive the first indication information. The first indication information is configured to indicate whether the first ephemeris information corresponds to the changed satellite.

[0152] In some embodiments, the first indication information is configured to be transmitted by a first message, and the first message does not include the first indication information in response. Petition 870250075840, dated 08 / 27 / 2025, p. 52 / 87 44 / 55 when the terminal device does not receive the indication information at the first moment.

[0153] In some embodiments, an effective moment of the first ephemeris information is a second moment, and whether or not the first ephemeris information corresponds to the altered satellite is determined based on the second moment.

[0154] In some embodiments, when the difference between the second moment and the first moment is less than or equal to a first time limit, the first ephemeris information corresponds to the altered satellite; or, when the second moment is later than or equal to the first moment, the first ephemeris information corresponds to the altered satellite.

[0155] In some embodiments, the terminal device is further configured to receive the second indication information. The second indication information is configured to indicate that a satellite corresponding to a first neighboring cell of the terminal device will become the satellite corresponding to the first cell.

[0156] In some embodiments, the ephemeris information of a first neighboring cell occupies a first position in a list of ephemeris information, and whether the satellite corresponding to the first neighboring cell for the terminal device will become the satellite corresponding to the first cell or not is determined based on the first position.

[0157] In some embodiments, in response to the first position being an Nth position in the ephemeris information list for one or more neighboring cells, the satellite corresponding to the first neighboring cell will become the satellite corresponding to the first cell, where N is a positive integer.

[0158] In some forms of realization, a fourth moment Petition 870250075840, dated 08 / 27 / 2025, page 53 / 87 45 / 55 corresponding to the ephemeris information of the changed satellite is determined based on the following subframe limits: a subframe limit before the satellite change; or a subframe limit after the satellite change.

[0159] In some embodiments, the fourth moment includes at least one moment of invalidity of the altered satellite ephemeris information or the effective moment of the altered satellite ephemeris information.

[0160] In some embodiments, the third operation is associated with one or more of the following: a power margin report (PHR), a time advance (TA), a power adjustment value, a random access, a K offset, and a radio link monitoring (RLM).

[0161] In some embodiments, the third operation includes one or more of the following: before the first moment, when the terminal device triggers the first PHR, cancel the triggering of the first PHR; trigger a second PHR; trigger a TA report; reset the power adjustment value to zero; some or all of the operations performed by the terminal device after the timeout of a time advance timer (TAT); clear a HARQ buffer; acquire an uplink synchronization via random access; when the terminal device initiates random access before the first moment and continues random access after the first moment, reset a first counter associated with random access and increment the first counter by one counting unit or keep the first counter unchanged;When the terminal device initiates random access before the first moment and continues random access after the first moment, perform a downlink synchronization in response to the downlink asynchronous operation; and / or reselect a random access resource according to the changed satellite signal quality; use the K offset configured by the changed satellite or the K offset with a value of 0; reset one second; Petition 870250075840, dated 08 / 27 / 2025, page 54 / 87 46 / 55 counter associated with RLM; and complete a first timer associated with RLM.

[0162] In some embodiments, the terminal device is further configured to receive the initial configuration information. The initial configuration information is used to control whether the terminal device performs the third operation.

[0163] In some embodiments, the initial configuration information is used to control whether the terminal device performs one or more of the following operations: before the first moment, when the terminal device triggers the first PHR, canceling the triggering of the first PHR; triggering the second PHR; triggering the TA report; resetting the power adjustment value to zero; some or all of the operations performed by the terminal device after the TAT timeout; clearing the HARQ buffer; acquiring uplink synchronization via random access; when the terminal device initiates random access before the first moment and continues random access after the first moment, resetting the first counter associated with random access and incrementing the first counter by one count unit, or keeping the first counter unchanged;when the terminal device initiates random access before the first moment and continues random access after the first moment, performing downlink synchronization in response to downlink desynchronization; and / or reselect the random access feature according to the changed satellite signal quality; using the K offset configured by the changed satellite or the K offset with a value of 0; resetting the second counter associated with the RLM; and interrupting the first timer associated with the RLM.

[0164] In some embodiments, the third operation is performed at a time later than or equal to the time of the first operation.

[0165] In some forms of realization, the effective moment of Petition 870250075840, dated 08 / 27 / 2025, page 55 / 87 47 / 55 The ephemeris information from the altered satellite is earlier than or equal to the first time.

[0166] Figure 14 is a schematic diagram illustrating the structure of a network device (1400) according to some embodiments of the present disclosure. The network device (1400) may include a determination unit (1410) and a configuration unit (1420).

[0167] The determination unit (1410) is configured to determine a first moment, where the first moment refers to a satellite change moment corresponding to a first cell for the terminal device.

[0168] The configuration unit (1420) is configured to set up one or more of the following information according to the first moment: ephemeris information of a changed satellite and a first operation performed by the terminal device according to the first moment. The first operation includes one or more of the following operations: a second operation performed by the terminal device after the terminal device starts using the ephemeris information of the changed satellite; and a third operation performed by the terminal device in response to the change of the satellite corresponding to the first cell.

[0169] In some embodiments, the network device is further configured to: transmit the first ephemeris information and the first indication information. The first indication information is configured to indicate whether the first ephemeris information corresponds to the changed satellite.

[0170] In some embodiments, the initial indication information is configured to be transmitted by a first message, and the first message does not include the initial indication information in response to the terminal device not receiving the indication information at the first time. Petition 870250075840, dated 08 / 27 / 2025, pp. 56 / 87 48 / 55

[0171] In some embodiments, the network device is further configured to transmit the first ephemeris information. An effective moment of the first ephemeris information is a second moment, and whether or not the first ephemeris information corresponds to the altered satellite is determined based on the second moment.

[0172] In some embodiments, when the difference between the second moment and the first moment is less than or equal to a first time limit, the first ephemeris information corresponds to the altered satellite; or, when the second moment is later than or equal to the first moment, the first ephemeris information corresponds to the altered satellite.

[0173] In some embodiments, the network device is further configured to transmit a second indication. The second indication is configured to indicate that a satellite corresponding to a first neighboring cell of the terminal device will become the satellite corresponding to the first cell.

[0174] In some embodiments, the ephemeris information of a first neighboring cell occupies a first position in a list of ephemeris information, and whether or not the satellite corresponding to the first neighboring cell of the terminal device will become the satellite corresponding to the first cell is determined based on the first position.

[0175] In some embodiments, in response to the first position being an Nth position in the ephemeris information list for one or more neighboring cells, the satellite corresponding to the first neighboring cell will become the satellite corresponding to the first cell, where N is a positive integer.

[0176] In some embodiments, the network device is further configured to transmit the initial configuration information. The initial configuration information is configured to control whether the Petition 870250075840, dated 08 / 27 / 2025, page 57 / 87 49 / 55 terminal device performs the third operation.

[0177] In some embodiments, the initial configuration information is set to control whether the terminal device performs one or more of the following operations: before the first moment, when the terminal device triggers a first PHR, cancel the triggering of the first PHR; trigger a second PHR; trigger a TA report; reset a power adjustment value; perform some or all of the operations performed by the terminal device after the timeout of a time advance timer (TAT); clear a HARQ buffer; acquire an uplink synchronization via random access; when the terminal device initiates random access before the first moment and continues random access after the first moment, resetting a first counter associated with random access and incrementing the first counter by one count unit or keeping the first counter unchanged;when the terminal device initiates random access before the first moment and continues random access after the first moment, performing a downlink synchronization in response to downlink desynchronization; and / or reselecting a random access resource based on the changed satellite signal quality; using the K offset configured by the changed satellite or the K offset with a value of 0; resetting a second counter associated with the RLM; and stopping a first timer associated with the RLM.

[0178] In some embodiments, the third operation is performed at a time later than or equal to the first time.

[0179] In some embodiments, an effective moment of the altered satellite ephemeris information is earlier than or equal to the first moment.

[0180] In some embodiments, each of the execution (1310), determination (1410) and configuration (1420) units can be Petition 870250075840, dated 08 / 27 / 2025, pp. 58 / 87 50 / 55 a processor (1510). The terminal device (1300) or the network device (1400) may also include a memory (1520) and / or a transceiver (1530), as shown in Figure 15.

[0181] Figure 15 is a schematic diagram illustrating the structure of a communication apparatus according to some embodiments of the present disclosure. The dashed lines in Figure 15 indicate that the units or modules are optional. The apparatus (1500) can be configured to implement the methods described in the previous method embodiments. The apparatus (1500) can be a chip, a terminal device, or a network device.

[0182] The apparatus (1500) may include one or more processors (1510). The processor(s) (1510) may enable the apparatus (1500) to implement the methods described in the preceding method embodiments. The processor(s) (1510) may be one or more general-purpose processors or dedicated processors. For example, the processor(s) may be one or more central processing units (CPUs). Alternatively, the processor(s) may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gates or transistor logic devices, or discrete hardware components, or the like. General-purpose processors may be microprocessors, or any conventional processors, or the like.

[0183] The device (1500) may also include one or more memories (1520). The memory(ies) (1520) store(s) programs that can be executed by the processor(s) (1510) to cause the processor(s) (1510) to execute(s) the methods described in the previous method embodiments. The memory(ies) (1520) may be Petition 870250075840, dated 08 / 27 / 2025, p. 59 / 87 51 / 55 independent of the processor(s) (1510) or can be integrated into the processor(s) (1510).

[0184] The device (1500) may also include the transceiver (1530). The processor(s) (1510) may communicate with other devices or chips via the transceiver (1530). For example, the processor(s) (1510) may transmit and receive data from other devices or chips via the transceiver (1530).

[0185] Some embodiments of this disclosure further provide a computer-readable storage medium configured to store programs. The computer-readable storage medium may be applied to the terminal device or network device provided in the embodiments of this disclosure, and the programs cause a computer to execute the methods that are executed by the terminal device or network device in the embodiments of this disclosure.

[0186] Some embodiments of this disclosure also provide a computer program product. The computer program product includes programs. The computer program product may be applied to the terminal device or network device provided in the embodiments of this disclosure, and the programs cause a computer to execute the methods that are executed by the terminal device or network device in the embodiments of this disclosure.

[0187] Some embodiments of this disclosure also provide a computer program. The computer program may be applied to the terminal device or network device provided in the embodiments of this disclosure, and the computer program causes a computer to execute the methods that are executed by Petition 870250075840, dated 08 / 27 / 2025, pp. 60 / 87 52 / 55 terminal device or by the network device in the ways this disclosure is made.

[0188] It should be understood that the terms “system” and “network” in this disclosure may be used interchangeably. Furthermore, the terms used in this disclosure are used only to explain the embodiments of this disclosure and are not intended to limit it. The terms “first,” “second,” “third,” “fourth,” and similar terms in the description, claims, and drawings of this disclosure are used to distinguish different objects rather than to describe a specific order. In addition, the terms “comprise” and “have,” and any variations thereof, are intended to encompass a non-exclusive inclusion.

[0189] In the embodiments of this disclosure, the term "indicates" mentioned herein may refer to a direct indication, or to an indirect indication, or it may mean that there is a relationship of association. For example, A indicates B, which may mean that A indicates B directly, for example, B can be obtained through A; or it may mean that A indicates B indirectly, for example, A indicates C, and B can be obtained through C; or it may mean that there is a relationship of association between A and B.

[0190] In the embodiments of this disclosure, 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 only determining B based solely on A, but rather, B can be determined based on A and / or other information.

[0191] In the forms of carrying out this disclosure, the term “correspondent” may mean that there is a direct or indirect correspondence between the two, or it may mean that there is a relationship of association between the two, or it may mean that there is a relationship such as indicating and being. Petition 870250075840, dated 08 / 27 / 2025, pp. 61 / 87 53 / 55 indicated, or configure and be configured.

[0192] In embodiments of this disclosure, “default” or “preconfigured” may be implemented by pre-storing corresponding codes, tables, or other formats that can be used to indicate related information in devices (for example, including terminal devices and network devices), and their specific implementations are not limited in this disclosure. For example, “default” may refer to “defined” in protocols.

[0193] In embodiments of this disclosure, the “protocol” may refer to a standard protocol in the field of communications and may include, for example, an LTE protocol, an NR protocol, and a related protocol applied to a future communications system, which is not limited to this disclosure.

[0194] In the embodiments of this disclosure, the term and / or is used merely to describe an association relationship between associated objects, indicating that there may be three relationships. For example, A and / or B may indicate that: only A exists, both A and B exist, and only B exists. In addition, the character / here generally indicates an OR relationship between the associated objects.

[0195] In embodiments of this disclosure, the term "including" may refer to direct or indirect inclusion. Alternatively, the term "including" mentioned in embodiments of this disclosure may be replaced by "indicating" or "used to determine." For example, "A includes B" may be replaced by "A indicates B" or "A is used to determine B."

[0196] In the ways this disclosure is made, the sequence numbers of the processes above do not signify execution sequences. The execution sequences of the processes must be determined according to the internal functions and logic of the processes and must not be Petition 870250075840, dated 08 / 27 / 2025, p. 62 / 87 54 / 55 interpreted as any limitation to the implementation processes of the ways in which this disclosure is carried out.

[0197] In the embodiments presented in this disclosure, it should be understood that the disclosed system, apparatus, and method may be implemented in other ways. For example, the embodiments of the described apparatus are merely illustrative. For example, the division of units is merely a logical function division, and there may be other ways of division in the actual implementation. For example, a plurality of units or components may be combined or integrated into another system, or some features may be ignored or not implemented. Furthermore, the mutual, direct, or communication couplings shown or discussed may be implemented using some interfaces. Indirect or communication couplings between the apparatus or units may be implemented in electrical, mechanical, or other forms.

[0198] The units described as separate parts may or may not be physically separate, and the parts displayed as units may or may not be physical units, may be located in one position, or may be distributed across a plurality of network units. Some or all of the units may be selected according to a real need to achieve the objectives of the embodiments of the solutions.

[0199] Furthermore, the functional units in the embodiments of this disclosure may be integrated into a processing unit, or each of the units may exist physically in isolation, or two or more units may be integrated into a unit.

[0200] All or some of the previous embodiments can be implemented using software, hardware, firmware, or any combination thereof. When software is used to implement the embodiments, the previous embodiments can be fully implemented. Petition 870250075840, dated 08 / 27 / 2025, pp. 63 / 87 55 / 55 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, the procedures or functions according to the embodiments of this disclosure are wholly or partially generated. The computer may be a general-purpose computer, a dedicated computer, a computer network, or other programmable devices. The computer instructions may be stored on a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium.For example, computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via a wired connection (such as a coaxial cable, fiber optic cable, and a digital subscriber line (DSL)) or a wireless connection (such as infrared, wireless, and microwave). A computer-readable storage medium can be any usable medium that can be read by a computer or a data storage device, such as a server or data center, formed by the integration of one or more usable media. The usable medium can be a magnetic medium (e.g., a floppy disk, a hard disk, or magnetic tape), an optical medium (e.g., a digital video disc (DVD)), a semiconductor medium (e.g., a solid-state drive (SSD)), or similar.

[0201] The foregoing descriptions are merely specific implementations of this disclosure, but the scope of protection of this disclosure is not limited to them. Any variation or substitution easily understood by a person skilled in the art, within the technical scope disclosed in this disclosure, will be covered by the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure will be subject to the scope of protection of the claims. Petition 870250075840, dated 08 / 27 / 2025, pp. 64 / 87

Claims

1 / 7 Claims 1. COMMUNICATION METHOD, characterized by comprising: receiving, by means of a terminal device (1300), a first message from a base station, wherein the first message indicates whether the first message comprises ephemeris information corresponding to a second satellite, wherein the first message is a radio resource control (RRC) message or a system information block (SIB); and performing, by means of the terminal device (1300), a third operation in response to a change of a satellite corresponding to the base station to the terminal device (1300), wherein the change comprises a change from a first satellite to the second satellite, and wherein the first satellite and the second satellite correspond to the base station, wherein the execution of the third operation comprises the use of an offset K with value 0 in response to the satellite change.

2. COMMUNICATION METHOD, according to claim 1, characterized in that the ephemeris information from the second satellite comprises an indication of a reference moment.

3. COMMUNICATION METHOD, according to claim 1, characterized by the terminal device (1300) ceasing to use ephemeris information from the first satellite before the change.

4. COMMUNICATION METHOD, according to claim 1, characterized in that the third operation comprises clearing a hybrid automatic repeat request (HARQ) buffer.

5. COMMUNICATION METHOD, according to claim 1, characterized in that the third operation comprises one or more of the following: Petition 870250075840, dated 08 / 27 / 2025, page 65 / 87 2 / 7 cancel the triggering of a first power margin report (PHR) triggered before satellite switching; trigger a second PHR; trigger a time advance report (TA); reset a power adjustment value to zero; perform one or more operations associated with a time-out time advance timer (TAT); obtain an uplink synchronization via a random access; in response to the terminal device (1300) initiate a random access before satellite switching and continue the random access after satellite switching, reset a first counter associated with the random access and increment the first counter by one counting unit or keep the first counter unchanged;In response to the terminal device (1300) initiating random access before satellite switching and continuing random access after satellite switching, perform at least one of the following actions: downlink synchronization in response to downlink desynchronization or reselect a random access resource according to the signal quality of the second satellite; reset a second counter associated with a radio link monitoring (RLM); and stop a first timer associated with the RLM.

6. COMMUNICATION METHOD, according to claim 1, further characterized by comprising: receiving, through the terminal device (1300), the first configuration information; wherein the first configuration information indicates whether the terminal device (1300) performs the third operation. Petition 870250075840, dated 08 / 27 / 2025, pp. 66 / 87 3 / 7 7. TERMINAL DEVICE (1300), characterized by comprising: at least one processor; one or more computer-readable non-transient storage media coupled to at least one processor and storing instructions for execution by at least one processor, wherein the instructions, when executed, cause the terminal device (1300) to perform the steps comprising: receiving a first message from a base station, wherein the first message indicates whether the first message comprises ephemeris information corresponding to a second satellite, wherein the first message is a Radio Resource Control (RRC) message or a System Information Block (SIB);and perform a third operation in response to a change of a satellite corresponding to the base station for the terminal device (1300), wherein the change comprises a change from a first satellite to the second satellite, and wherein the first satellite and the second satellite correspond to the base station, wherein the execution of the third operation comprises using an offset K with value 0 in response to the satellite change.; 8. TERMINAL DEVICE (1300), according to claim 9, characterized in that the ephemeris information from the second satellite comprises an indication of a reference moment.

9. TERMINAL DEVICE (1300), according to claim 9, characterized in that the steps further comprise: interrupting the use of ephemeris information from the first satellite before the change.

10. TERMINAL DEVICE (1300), according to claim 9, characterized in that the third operation comprises clearing a hybrid automatic repeat request (HARQ) buffer. Petition 870250075840, dated 08 / 27 / 2025, page 67 / 87 4 / 7 11. TERMINAL DEVICE (1300), according to claim 9, characterized in that the third operation comprises one or more of the following: canceling the triggering of a first power margin report (PHR) triggered before satellite switching; triggering a second PHR; triggering a time advance report (TA); resetting a power adjustment value to zero; performing one or more operations associated with an expiring time advance timer (TAT); obtaining an uplink synchronization via a random access; in response, the terminal device (1300) initiates a random access before satellite switching and continues the random access after satellite switching, resets a first counter associated with the random access, and increments the first counter by one counting unit or keeps the first counter unchanged;in response to the terminal device (1300) initiating random access before satellite switching and continuing random access after satellite switching, performing at least one downlink synchronization in response to downlink desynchronization or reselecting a random access resource according to the signal quality of the second satellite; resetting a second counter associated with a radio link monitoring (RLM); and stopping a first timer associated with the RLM.; 12. TERMINAL DEVICE (1300), according to claim 9, characterized in that the steps further comprise: receiving the first configuration information; Petition 870250075840, dated 08 / 27 / 2025, page 68 / 87 5 / 7 wherein the first configuration information indicates whether the terminal device (1300) performs the third operation. 13.ONE OR MORE NON-TRANSIENT COMPUTER-READABLE STORAGE MEDIA, characterized by storing computer instructions that, when executed by one or more processors, cause a computing device to perform steps comprising: receiving a first message from a base station, wherein the first message indicates whether the first message comprises ephemeris information corresponding to a second satellite, wherein the first message is a Radio Resource Control (RRC) message or a System Information Block (SIB); and performing a third operation in response to a change from a satellite corresponding to the base station to a terminal device (1300), wherein the change comprises a change from a first satellite to the second satellite, and wherein the first satellite and the second satellite correspond to the base station, wherein the execution of the third operation comprises the use of an offset K with value 0 in response to the satellite change.

14. ONE OR MORE NON-TRANSIENT COMPUTER-READABLE STORAGE MEDIA, according to claim 13, characterized in that the ephemeris information from the second satellite comprises an indication of a reference moment.

15. ONE OR MORE NON-TRANSIENT COMPUTER-READABLE STORAGE MEDIA, according to claim 13, characterized in that the steps further comprise: interrupting the use of ephemeris information from the first satellite before the change.

16. ONE OR MORE NON-TRANSIENT COMPUTER-READABLE STORAGE MEDIA, according to claim 13, Petition 870250075840, dated 27 / 08 / 2025, pp. 69 / 87 6 / 7, characterized in that the third operation comprises clearing a hybrid automatic repeat request (HARQ) buffer.

17. ONE OR MORE NON-TRANSIENT COMPUTER-READABLE STORAGE MEANS, according to claim 13, characterized in that the third operation comprises one or more of the following: canceling the firing of a first power margin report (PHR) that is fired before satellite switching; firing a second PHR; firing a time advance report (TA); resetting a power adjustment value to zero; performing one or more operations associated with an expiring time advance timer (TAT); obtaining an uplink synchronization by means of a random access; in response to the terminal device (1300) initiating a random access before satellite switching and continuing the random access after satellite switching, resetting a first counter associated with the random access and incrementing the first counter by one counting unit or keeping the first counter unchanged;in response to the terminal device (1300) initiating random access before satellite switching and continuing random access after satellite switching, performing at least one downlink synchronization in response to downlink desynchronization or reselecting a random access resource according to the signal quality of the second satellite; resetting a second counter associated with a radio link monitoring (RLM); and stopping a first timer associated with the RLM.; 18. ONE OR MORE NON-TRANSIENT COMPUTER-READABLE STORAGE MEDIA Petition 870250075840, dated 08 / 27 / 2025, pp. 70 / 87 7 / 7, according to claim 13, characterized in that the steps further comprise: receiving the first configuration information, wherein the first configuration information indicates whether the terminal device (1300) performs the third operation. Petition 870250075840, dated 08 / 27 / 2025, pp. 71 / 87

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