Target satellite timing method and device and readable storage medium

Abstract

The invention provides an application target satellite timing method and device and a readable storage medium, and relates to the technical field of communication. The method comprises: sending first indication information to a base station, the first indication information being used for indicating the UE to obtain synchronization of a target satellite. According to the invention, the problem of interference possibly occurring in a soft switch scene is solved, and the scheduling complexity of the base station is further reduced.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a method, device and readable storage medium for applying target satellite timing. Background Art

[0002] In the unchanged PCI scenario (i.e., the physical cell identifier (PCI) remains unchanged), there is a situation called soft satellite switch, that is, before sat1 (here refers to the source satellite) stops service, sat2 (here refers to the target satellite) has started coverage, and sat1 and sat2 have a period of time to cover a certain area on the ground together. The time when sat1 stops service is t-service, the time when sat2 starts service is t-start, and t-start <t-service。

[0003] For the soft satellite switch scenario, between t-start and t-service, the source satellite and the target satellite will provide services to the UE at the same time. During this period, the UE can perform the synchronization process with the target satellite. However, after the UE obtains the downlink timing and / or timing advance (TA) of the target satellite, whether it can be applied immediately needs further discussion. According to analysis, if it is applied immediately, there are the following problems: the time when each UE obtains synchronization with the target satellite is not consistent. For example, if a UE immediately sends a preamble according to the timing of the target satellite after completing the downlink synchronization with the target satellite; or, after the UE completes the downlink synchronization with the target satellite and obtains the TA through the without RACH method, it immediately performs uplink and downlink transmission according to the timing and TA of the target satellite. Since the network (here refers to the base station) does not know when the UE obtains downlink synchronization and / or uplink synchronization, if the UE autonomously decides to perform uplink and downlink transmission according to the timing of the target satellite, it may cause interference to the UE that performs uplink and downlink transmission according to the timing and TA of the source satellite, thereby increasing the scheduling complexity of the network.

[0004] Therefore, the existing technology cannot effectively solve the interference problem that may occur in the soft satellite switch scenario, thereby increasing the scheduling complexity of the base station. Summary of the invention

[0005] The present application provides a method, device and readable storage medium for applying target satellite timing, which solves the interference problem that may occur in the softsatellite switch scenario, thereby reducing the scheduling complexity of the base station.

[0006] In a first aspect, the present application provides a method for applying target satellite timing, the method being performed by a terminal UE, the method comprising:

[0007] Sending first indication information to a base station, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

[0008] Optionally, the first indication information includes any one of the following:

[0009] Instructing the UE to acquire downlink synchronization of the target satellite;

[0010] Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite;

[0011] Instruct the UE to acquire uplink synchronization of the target satellite.

[0012] In an embodiment of the present application, by sending a first indication message to the base station, the UE is indicated to have obtained the downlink synchronization and / or uplink synchronization of the target satellite. Specifically, obtaining the downlink synchronization of the target satellite means obtaining the downlink timing of the target satellite, and obtaining the uplink synchronization of the target satellite means obtaining the TA of the target satellite. Specifically, obtaining the downlink timing of the target satellite means obtaining the downlink timing of transparent forwarding of the base station through the target satellite, and obtaining the TA of the target satellite means obtaining the TA of accessing the base station through the target satellite. In this way, the network (here refers to the base station, which will not be repeated below) knows when the UE has obtained downlink synchronization (here refers to obtaining the downlink timing of the target satellite) and / or uplink synchronization (here including TA). It solves the interference problem that may occur in the softsatellite switch scenario, thereby reducing the scheduling complexity of the network, as well as reducing the receiving complexity and energy consumption of the network.

[0013] Optionally, the sending the first indication information to the base station includes any one of the following:

[0014] When the downlink timing of the target satellite is acquired, sending the first indication information to the base station;

[0015] When the downlink timing of the target satellite and the timing advance TA of the target satellite are acquired, sending the first indication information to the base station;

[0016] When the TA of the target satellite is acquired, the first indication information is sent to the base station.

[0017] In the embodiment of the present application, under what conditions does the UE send which indication, that is, when what conditions are met, the first indication information is sent to the base station, which can be implemented through at least three following methods (or behaviors): Method 1, when the UE obtains the downlink timing of the target satellite, the UE sends the first indication information to the base station, wherein the first indication information is used to indicate that the UE has obtained the downlink synchronization of the target satellite, which here refers to the downlink timing of the target satellite; Method 2, when the UE obtains the downlink timing of the target satellite and the TA of the target satellite, the UE sends the first indication information to the base station, wherein the first indication information is used to indicate that the UE has obtained the downlink synchronization and uplink synchronization of the target satellite, which here refers to the downlink timing of the target satellite and the TA of the target satellite; Method 3, when the UE obtains the TA of the target satellite, the UE sends the first indication information to the base station, wherein the first indication information is used to indicate that the UE has obtained the uplink synchronization, which here refers to the TA of the target satellite. Specifically, the first indication information can be sent to the base station in the form of RRC signaling, MAC CE or UCI.

[0018] Optionally, the sending the first indication information to the base station includes:

[0019] Sending the first indication information to the base station via a source satellite; or,

[0020] The first indication information is sent to the base station via the target satellite.

[0021] In the embodiment of the present application, how the UE sends the first indication information to the base station can be implemented in at least two of the following ways: Mode 11, according to the downlink timing of the source satellite and the TA of the source satellite, the first indication information is sent to the base station, specifically, according to the downlink timing and TA of the source satellite accessing the service cell, the first indication information is sent to the base station; Mode 12, according to the downlink timing of the target satellite and the TA of the target satellite, the first indication information is sent to the base station, specifically, according to the downlink timing and TA of the target satellite accessing the service cell, the first indication information is sent to the base station. Therefore, any of the above methods can be used to implement the UE sending the first indication information to the base station.

[0022] Optionally, after sending the first indication information to the base station, the method further includes:

[0023] Receive second indication information; wherein the second indication information includes at least one of the following:

[0024] Instructing the UE whether to apply the downlink timing of the target satellite;

[0025] Indicating whether the UE performs a random access procedure;

[0026] Instructing the UE whether to use the TA of the target satellite for uplink transmission;

[0027] Indicating whether the UE accesses a target satellite;

[0028] designated time;

[0029] The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

[0030] Specifically, the second indication information may be sent to the UE in the form of RRC signaling, MAC CE or DCI.

[0031] Optionally, the receiving the second indication information includes:

[0032] receiving the second indication information sent by the source satellite; or,

[0033] The second indication information sent by the target satellite is received.

[0034] In an embodiment of the present application, the UE receives the second indication information sent by the base station, which can be achieved through at least two of the following methods: Method 21, receiving the second indication information sent by the base station according to the downlink timing of the source satellite; Method 22, receiving the second indication information sent by the base station according to the downlink timing of the target satellite.

[0035] Optionally, before sending the first target indication information to the base station, the method further includes:

[0036] Receiving information configured by the base station;

[0037] The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

[0038] Optionally, the method of applying the downlink timing of the target satellite includes:

[0039] After sending first indication information of acquiring downlink synchronization of accessing the serving cell through the target satellite to the base station, applying the downlink timing of the target satellite; or,

[0040] After sending the first indication information to the base station to obtain the downlink synchronization of accessing the service cell through the target satellite, and receiving the second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite to perform a random access process, the downlink timing of the target satellite is applied.

[0041] Optionally, the manner of applying the downlink timing of the target satellite and the TA of the target satellite includes any one of the following:

[0042] After sending first indication information of acquiring downlink synchronization and uplink synchronization of accessing a serving cell through the target satellite to the base station, applying the downlink timing of the target satellite and the TA of the target satellite;

[0043] After sending first indication information to the base station to obtain downlink synchronization and uplink synchronization of accessing the serving cell through the target satellite, and receiving second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite and the TA of the target satellite, applying the downlink timing of the target satellite and the TA of the target satellite;

[0044] According to the specified time in the second indication information sent by the base station, the downlink timing of the target satellite and the TA of the target satellite are applied.

[0045] In an embodiment of the present application, the method in which the UE applies the downlink timing of the target satellite can be implemented through at least two of the following methods: Method 31, after the UE sends an indication of obtaining downlink synchronization for accessing the service cell through the target satellite (here, the UE sends the first indication information used to indicate that the downlink synchronization for accessing the service cell through the target satellite has been obtained), the UE applies the downlink timing of the target satellite to execute the RACH process (i.e., a random access process); Method 32, after the UE sends an indication of obtaining downlink synchronization for accessing the service cell through the target satellite, and receives information from the base station instructing the UE to apply the downlink timing of the target satellite to execute RACH (here, the UE receives the second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite to execute the random access process), the UE applies the downlink timing of the target satellite to execute the RACH process.

[0046] The way in which the UE applies the downlink timing of the target satellite and the TA of the target satellite can be implemented in at least three of the following ways: Way 41, after the UE sends an indication of obtaining downlink synchronization and uplink synchronization of accessing the service cell through the target satellite (here refers to the first indication information sent by the UE that the downlink synchronization and uplink synchronization of accessing the service cell through the target satellite is obtained), the UE applies the downlink timing of the target satellite and the TA of the target satellite for uplink and downlink transmission; Way 42, after the UE sends an indication of obtaining downlink synchronization and uplink synchronization of accessing the service cell through the target satellite and receives information from the network base station instructing the UE to apply the timing and TA of the target satellite for uplink and downlink transmission (here refers to the second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite and the TA of the target satellite), the UE applies the downlink timing of the target satellite and the TA of the target satellite for uplink and downlink transmission; Way 43, at the time specified by the base station (here refers to the specified time indicated in the second indication information), the UE starts to apply the downlink timing of the target satellite and the TA of the target satellite for uplink and downlink transmission.

[0047] Optionally, the method may further include at least one of the following:

[0048] Triggering a random access process;

[0049] applying the TA of the target satellite;

[0050] Monitoring a physical downlink control channel PDCCH of the target satellite;

[0051] Perform uplink and downlink transmission according to the downlink timing of the target satellite and the TA of the target satellite;

[0052] Restart the timing advance timer TAT;

[0053] Read SIB1;

[0054] Read SIB19.

[0055] Optionally, the method further comprises:

[0056] Reporting to the base station whether a capability of obtaining uplink synchronization by not performing a random access process is supported.

[0057] In an embodiment of the present application, before sending the first indication information to the base station, the UE sends to the base station information indicating whether it supports the ability to obtain uplink synchronization with the target satellite by not performing a random access process. Specifically, obtaining uplink synchronization by not performing a random access process refers to the ability to obtain uplink synchronization with the target satellite by not performing a random access process. The capability refers to the ability to obtain uplink synchronization by not performing a random access process in an unchanged PCI scenario.

[0058] Optionally, before sending the first target indication information to the base station, the method further includes:

[0059] Stop sending the sounding reference signal SRS according to the downlink timing of the source satellite at a preset time, and after acquiring the downlink timing of the target satellite, send the SRS according to the downlink timing of the target satellite; or,

[0060] After the downlink timing of the target satellite is acquired, the SRS resources configured for the target satellite are sent according to the downlink timing of the target satellite.

[0061] In an embodiment of the present application, before the UE sends the first indication information to the base station, the UE may send a signal in at least two of the following ways: Mode 51, at a preset time (for example, t-start or a specified time), stop sending SRS according to the timing of the source satellite (here refers to the downlink timing, the timing below refers to the downlink timing, and will not be repeated below), and after obtaining the downlink synchronization of the target satellite (here refers to obtaining the downlink timing of the target satellite), send SRS according to the timing of the target satellite (here refers to the downlink timing of the target satellite); (the UE uses the same set of SRS resources during this period). Mode 52, after obtaining the downlink synchronization of the target satellite (here refers to obtaining the downlink timing of the target satellite), send the SRS resources configured for the target satellite according to the timing of the target satellite (here refers to the downlink timing of the target satellite), and maintain the uplink and downlink transmission of the downlink timing of the source satellite; (configure a separate SRS resource for the target satellite).

[0062] Optionally, before sending the first target indication information to the base station, a method of receiving the TA of the target satellite includes:

[0063] Receive the TA of the target satellite sent by the source satellite; or,

[0064] Receive the TA of the target satellite sent by the target satellite.

[0065] In the embodiment of the present application, the UE may receive the TA of the target satellite in at least two ways: in mode 61, the UE receives the TA of the target satellite sent by the base station according to the downlink timing of the source satellite; in mode 62, the UE receives the TA of the target satellite sent by the base station according to the downlink timing of the target satellite. Specifically, the TA value of the target satellite is received through the source satellite, such as MAC CE; after applying the downlink timing of the target satellite, the UE monitors the downlink transmission at the target satellite, and receives the TA value of the target satellite through the target satellite, such as the TA command sent by the target satellite.

[0066] In a second aspect, the present application provides a method for applying target satellite timing, the method being performed by a base station, the method comprising:

[0067] Receive first indication information sent by a UE, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

[0068] Optionally, the first indication information includes any one of the following:

[0069] Instructing the UE to acquire downlink synchronization of the target satellite;

[0070] Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite;

[0071] Instruct the UE to acquire uplink synchronization of the target satellite.

[0072] In an embodiment of the present application, by receiving the first indication information sent by the UE, it is indicated that the UE has obtained the downlink synchronization and / or uplink synchronization of the target satellite. Specifically, obtaining the downlink synchronization of the target satellite means obtaining the downlink timing of the target satellite, and obtaining the uplink synchronization of the target satellite means obtaining the TA of the target satellite. Specifically, obtaining the downlink timing of the target satellite means obtaining the downlink timing of transparent forwarding of the base station through the target satellite, and obtaining the TA of the target satellite means obtaining the TA of accessing the base station through the target satellite. In this way, the network knows when the UE has obtained downlink synchronization (here refers to obtaining the downlink timing of the target satellite) and / or uplink synchronization (here including TA). It solves the interference problem that may occur in the soft satellite switch scenario, thereby reducing the scheduling complexity of the network, as well as reducing the receiving complexity and energy consumption of the network.

[0073] Optionally, the method comprises any of the following:

[0074] The first indication information is sent to the base station by the UE when the UE obtains the downlink timing of the target satellite;

[0075] The first indication information is sent to the base station by the UE when acquiring the downlink timing of the target satellite and the TA of the target satellite;

[0076] The first indication information is sent to the base station by the UE when acquiring the TA of the target satellite.

[0077] In an embodiment of the present application, the base station receives the first indication information sent by the UE, which can be implemented in at least three of the following ways (or behaviors): Way 1, when the UE obtains the downlink timing of the target satellite, the UE sends the first indication information to the base station, and the base station receives the first indication information sent by the UE in the way 1, wherein the first indication information is used to indicate that the UE has obtained the downlink synchronization of the target satellite, which here refers to the downlink timing of the target satellite; Way 2, when the UE obtains the downlink timing of the target satellite and the TA of the target satellite, the UE sends the first indication information to the base station, and the base station receives the first indication information sent by the UE in the way 2, wherein the first indication information is used to indicate that the UE has obtained the downlink synchronization and uplink synchronization of the target satellite, which here refers to the downlink timing of the target satellite and the TA of the target satellite; Way 3, when the UE obtains the TA of the target satellite, the UE sends the first indication information to the base station, and the base station receives the first indication information sent by the UE in the way 3, wherein the first indication information is used to indicate that the UE has obtained the uplink synchronization, which here refers to the TA of the target satellite.

[0078] Specifically, the first indication information may be sent to the base station in the form of RRC signaling, MAC CE or UCI.

[0079] Optionally, the receiving first indication information sent by the UE includes:

[0080] Receiving first indication information sent by the UE through a source satellite; or,

[0081] The first indication information sent by the UE is received through the target satellite.

[0082] In the embodiment of the present application, how the base station receives the first indication information sent by the UE can be implemented in at least two of the following ways: way 11, receiving the first indication information sent by the UE according to the timing of the source satellite, specifically, receiving the first indication information sent by the UE according to the timing of the source satellite accessing the service cell; way 12, receiving the first indication information sent by the UE according to the timing of the target satellite, specifically, receiving the first indication information sent by the UE according to the timing of the target satellite accessing the service cell. Therefore, the base station can receive the first indication information sent by the UE through any of the above ways.

[0083] Optionally, after receiving the first indication information sent by the UE, the method further includes:

[0084] Sending second indication information to the UE; wherein the second indication information includes at least one of the following:

[0085] Instructing the UE whether to apply the downlink timing of the target satellite;

[0086] Indicating whether the UE performs a random access procedure;

[0087] Instructing the UE whether to use the TA of the target satellite for uplink transmission;

[0088] Indicating whether the UE accesses a target satellite;

[0089] designated time;

[0090] The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

[0091] Specifically, the second indication information may be sent to the UE in the form of RRC signaling, MAC CE or DCI.

[0092] Optionally, the sending the second indication information to the UE includes:

[0093] Sending second indication information to the UE via a source satellite; or,

[0094] Send second indication information to the UE through the target satellite.

[0095] In an embodiment of the present application, the base station sends the second indication information to the UE, which can be implemented in at least two of the following ways: Way 21, the base station sends the second indication information to the UE according to the timing of the source satellite; Way 22, the base station sends the second indication information to the UE according to the timing of the target satellite.

[0096] Optionally, before receiving the first indication information sent by the UE, the method further includes:

[0097] Sending configuration information to the UE;

[0098] The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

[0099] Optionally, the method further comprises:

[0100] receiving a report from the UE as to whether it supports a capability of obtaining uplink synchronization in a manner not to perform a random access process.

[0101] Specifically, obtaining uplink synchronization by not executing a random access procedure refers to the ability to obtain uplink synchronization with a target satellite by not executing a random access procedure. The ability refers to the ability to obtain uplink synchronization by not executing a random access procedure in an unchanged PCI scenario.

[0102] Optionally, the manner of sending the TA of the target satellite to the UE includes:

[0103] Sending the TA of the target satellite to the UE via the source satellite; or,

[0104] The TA of the target satellite is sent to the UE via the target satellite.

[0105] In the embodiment of the present application, the method of sending the TA of the target satellite to the UE by the base station can be implemented in at least two of the following methods: method 31, the base station sends the TA of the target satellite to the UE according to the timing of the source satellite; method 32, the UE sends the TA of the target satellite to the UE according to the timing of the target satellite. Specifically, the TA value of the target satellite is sent through the source satellite, such as MAC CE; after applying the downlink timing of the target satellite, the UE monitors the downlink transmission on the target satellite, the base station sends the TA value of the target satellite through the target satellite, and the UE receives the TA value of the target satellite through the target satellite, such as the TA command sent by the target satellite.

[0106] In a third aspect, the present application provides a device for applying target satellite timing, where the device is executed by a UE, and the device includes:

[0107] The sending unit is used to send first indication information to the base station, where the first indication information is used to instruct the UE to acquire synchronization with the target satellite.

[0108] In a fourth aspect, the present application provides a device for applying target satellite timing, the device being executed by a base station, and the device comprising:

[0109] The receiving unit is used to receive first indication information sent by the UE, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

[0110] In a fifth aspect, the present application provides a device for applying target satellite timing, the device being executed by a UE, the device comprising a memory, a transceiver, and a processor:

[0111] A memory for storing a computer program; a transceiver for transmitting and receiving data under the control of the processor; and a processor for reading the computer program in the memory and performing the following operations:

[0112] Sending first indication information to a base station, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

[0113] Optionally, the first indication information includes any one of the following:

[0114] Instructing the UE to acquire downlink synchronization of the target satellite;

[0115] Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite;

[0116] Instruct the UE to acquire uplink synchronization of the target satellite.

[0117] Optionally, the processor is configured to, when sending the first indication information to the base station, specifically include any of the following items:

[0118] When the downlink timing of the target satellite is acquired, sending the first indication information to the base station;

[0119] When the downlink timing of the target satellite and the timing advance TA of the target satellite are acquired, sending the first indication information to the base station;

[0120] When the TA of the target satellite is acquired, the first indication information is sent to the base station.

[0121] Optionally, the processor is configured to, when sending the first indication information to the base station, specifically include any of the following items:

[0122] Sending the first indication information to the base station via a source satellite; or,

[0123] The first indication information is sent to the base station via the target satellite.

[0124] Optionally, the processor is configured to, after sending the first indication information to the base station, perform the following operations:

[0125] Receive second indication information; wherein the second indication information includes at least one of the following:

[0126] Instructing the UE whether to apply the downlink timing of the target satellite;

[0127] Indicating whether the UE performs a random access procedure;

[0128] Instructing the UE whether to use the TA of the target satellite for uplink transmission;

[0129] Indicating whether the UE accesses a target satellite;

[0130] designated time;

[0131] The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

[0132] Optionally, the processor is configured to, before sending the first indication information to the base station, perform the following operations:

[0133] Receiving information configured by the base station;

[0134] The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

[0135] Optionally, the processor is used to, when applying the downlink timing of the target satellite, specifically include the following:

[0136] After sending first indication information of acquiring downlink synchronization of accessing the serving cell through the target satellite to the base station, applying the downlink timing of the target satellite; or,

[0137] After sending the first indication information to the base station to obtain the downlink synchronization of accessing the service cell through the target satellite, and receiving the second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite to perform a random access process, the downlink timing of the target satellite is applied.

[0138] Optionally, the processor is used to, when applying the downlink timing of the target satellite and the TA of the target satellite, specifically include any of the following:

[0139] After sending first indication information of acquiring downlink synchronization and uplink synchronization of accessing a serving cell through the target satellite to the base station, applying the downlink timing of the target satellite and the TA of the target satellite;

[0140] After sending first indication information to the base station to obtain downlink synchronization and uplink synchronization of accessing the serving cell through the target satellite, and receiving second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite and the TA of the target satellite, applying the downlink timing of the target satellite and the TA of the target satellite;

[0141] According to the specified time in the second indication information sent by the base station, the downlink timing of the target satellite and the TA of the target satellite are applied.

[0142] Optionally, the processor is further configured to perform the following operations:

[0143] Reporting to the base station whether a capability of obtaining uplink synchronization by not performing a random access process is supported.

[0144] Optionally, the processor is configured to perform the following operations before sending the first indication information to the base station:

[0145] Stop sending the sounding reference signal SRS in accordance with the downlink timing of the source satellite at a preset time, and after acquiring the downlink timing of the target satellite, send the SRS in accordance with the downlink timing of the target satellite; or,

[0146] After the downlink timing of the target satellite is acquired, the SRS resources configured for the target satellite are sent according to the downlink timing of the target satellite.

[0147] Optionally, the processor is configured to, before sending the first indication information to the base station, when receiving the TA of the target satellite, specifically include:

[0148] Receive the TA of the target satellite sent by the source satellite; or,

[0149] Receive the TA of the target satellite sent by the target satellite.

[0150] In a sixth aspect, the present application provides a device for applying target satellite timing, the device being executed by a base station, the device comprising a memory, a transceiver, and a processor:

[0151] A memory for storing a computer program; a transceiver for transmitting and receiving data under the control of the processor; and a processor for reading the computer program in the memory and performing the following operations:

[0152] Receive first indication information sent by a UE, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

[0153] Optionally, the first indication information includes any one of the following:

[0154] Instructing the UE to acquire downlink synchronization of the target satellite;

[0155] Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite;

[0156] Instruct the UE to acquire uplink synchronization of the target satellite.

[0157] Optionally, the first indication information is sent to the base station by the UE when acquiring the downlink timing of the target satellite; or,

[0158] The first indication information is sent to the base station by the UE when the UE obtains the downlink timing of the target satellite and the TA of the target satellite; or,

[0159] The first indication information is sent to the base station by the UE when acquiring the TA of the target satellite.

[0160] Optionally, the processor is configured to, after receiving the first indication information sent by the UE, perform the following operations:

[0161] Sending second indication information to the UE; wherein the second indication information includes at least one of the following:

[0162] Instructing the UE whether to apply the downlink timing of the target satellite;

[0163] Indicating whether the UE performs a random access procedure;

[0164] Instructing the UE whether to use the TA of the target satellite for uplink transmission;

[0165] Indicating whether the UE accesses a target satellite;

[0166] designated time;

[0167] The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

[0168] Optionally, the processor is configured to, when sending the second indication information to the UE, specifically include:

[0169] Sending second indication information to the UE via a source satellite; or,

[0170] Send second indication information to the UE through the target satellite.

[0171] Optionally, the processor is configured to, before receiving the first indication information sent by the UE, perform the following operations:

[0172] Sending configuration information to the UE;

[0173] The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

[0174] Optionally, the processor is further configured to perform the following operations:

[0175] receiving a report from the UE as to whether it supports a capability of obtaining uplink synchronization in a manner not to perform a random access process.

[0176] Optionally, the processor is configured to, when sending the TA of the target satellite to the UE, specifically include:

[0177] Sending the TA of the target satellite to the UE via the source satellite; or,

[0178] The TA of the target satellite is sent to the UE via the target satellite.

[0179] In a seventh aspect, the present application provides a non-transitory readable storage medium, wherein the non-transitory readable storage medium stores a computer program, and the computer program is used to enable a processor to execute any of the methods described above.

[0180] The present application provides a method, device and readable storage medium for applying target satellite timing, and sends a first indication message to a base station, wherein the first indication message is used to indicate that the UE has acquired synchronization with the target satellite. That is, by sending the first indication message to the base station, the UE is indicated to have acquired synchronization with the target satellite. In this way, the network knows when the UE has acquired synchronization with the target satellite, and effectively solves the problem that the network does not know when the UE has acquired downlink synchronization and / or uplink synchronization. If the UE autonomously decides to perform uplink and downlink transmission according to the timing of the target satellite, it may cause interference to the UE that performs uplink and downlink transmission according to the timing of the source satellite and the TA, thereby reducing the scheduling complexity of the network.

[0181] It should be understood that the contents described in the above summary of the invention are not intended to limit the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0182] In order to more clearly illustrate the technical solutions in the present application or the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0183] Figure 1 A schematic diagram of an unchanged PCI scenario provided in an embodiment of the present application;

[0184] Figure 2 An interactive schematic diagram of a method for applying target satellite timing provided in an embodiment of the present application;

[0185] Figure 3 An interactive schematic diagram of a method for applying target satellite timing provided by yet another embodiment of the present application;

[0186] Figure 4 A schematic diagram of the structure of a device for applying target satellite timing provided in an embodiment of the present application;

[0187] Figure 5 A schematic diagram of the structure of an apparatus for applying target satellite timing according to yet another embodiment of the present application. DETAILED DESCRIPTION

[0188] The term "and / or" in this application describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0189] In the embodiments of the present application, the term "plurality" refers to two or more than two, and other quantifiers are similar.

[0190] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0191] In order to clearly understand the technical solution of the present application, the solution of the prior art is first introduced in detail. In the research of 3GPP R17 / R18, the satellite is connected to the ground base station through the gateway as a transparent forwarding unit, and the cell coverage provided by the satellite depends on the configuration of the base station. For quasi-earth fixed cells (quasi-earth fixed), through network architecture design and deployment, it is possible to achieve the effect that the satellite covering a certain area changes while the cell does not change, that is, the PCI and frequency of the cell serving the area do not change. Figure 1 As shown in the figure, at time T1, gNB1 provides services to area A through sat1 (here refers to satellite 1, i.e., source satellite). At time T2, gNB1 continues to provide services to area A through sat2 (here refers to satellite 1, i.e., target satellite). gNB 1 can be designed to achieve the PCI and frequency (i.e., Figure 1 F1 in the figure), cell configuration and UE configuration remain unchanged. From the UE's perspective, the cell has not changed, and no handover, conditional handover or cell reselection is required.

[0192] In the unchanged PCI scenario, there is a case of soft satellite switch, that is, before sat1 stops service, sat2 has started to cover, and sat1 and sat2 have a period of time to cover area A together. The time when sat1 stops service is t-service, and the time when sat2 starts service is t-start. <t-service。

[0193] For the soft satellite switch scenario, between t-start and t-service, the source satellite and the target satellite will provide services to the UE at the same time. During this period, the UE performs the synchronization process with the target satellite. However, after the UE obtains the downlink timing and / or timing advance (TA) of the target satellite, whether it can be applied immediately needs further discussion. According to analysis, if it is applied immediately, there are the following problems: the time when each UE obtains synchronization with the target satellite is not consistent. For example, if a UE immediately sends a preamble according to the timing of the target satellite after completing the downlink synchronization with the target satellite; or, after the UE completes the downlink synchronization with the target satellite and obtains the TA through the without RACH method, it immediately performs uplink and downlink transmission according to the timing and TA of the target satellite. Since the network (here refers to the base station) does not know when the UE obtains downlink synchronization and / or uplink synchronization, if the UE autonomously decides to perform uplink and downlink transmission according to the timing of the target satellite, it may cause interference to the UE that performs uplink and downlink transmission according to the timing and TA of the source satellite, thereby increasing the scheduling complexity of the network.

[0194] Therefore, the existing technology cannot effectively solve the interference problem that may occur in the soft satellite switch scenario, thereby increasing the scheduling complexity of the base station.

[0195] The inventors further discovered that in order to solve the interference problem that may occur in the soft satellite switch scenario and thereby reduce the scheduling complexity of the base station, after the UE obtains the downlink synchronization and / or uplink and downlink synchronization of the target satellite, it can report indication information (herein, the first indication information) to the network, so that the network knows when the UE obtains the downlink synchronization and / or uplink synchronization.

[0196] Therefore, based on the creative research of the above inventors, the method and device for applying target satellite timing proposed in the present application are proposed. In the present application, by sending a first indication message to the base station, the UE is indicated to have obtained synchronization with the target satellite, so that the network knows when the UE has obtained downlink synchronization and / or uplink synchronization, thereby solving the interference problem that may occur in the soft satellite switch scenario, thereby reducing the scheduling complexity of the network, and reducing the receiving complexity and energy consumption of the network.

[0197] Among them, the method and the device are based on the same application concept. Since the method and the device solve the problem in a similar principle, the implementation of the device and the method can refer to each other, and the repeated parts will not be repeated.

[0198] Embodiments of the present application will be described below with reference to the accompanying drawings.

[0199] It should be noted that, according to the way UE obtains uplink synchronization, it can be divided into RACH-based (i.e., performing a random access process) and without RACH (i.e., not performing a random access process) solutions. Among them, RACH-based means that after the UE obtains the downlink synchronization of the target satellite, it applies the timing of the target satellite to perform the RACH process to obtain the TA. Without RACH means that after the UE obtains the downlink synchronization of the target satellite, it calculates the TA of the target satellite based on the auxiliary parameters configured by the network. The following will be explained based on these two methods respectively.

[0200] In the present application, after acquiring downlink synchronization and / or uplink and downlink synchronization of the target satellite, the UE sends first indication information to the base station.

[0201] Optionally, the base station instructs the UE whether to apply the downlink timing of the target satellite and / or the TA of the target satellite or instructs the UE whether to perform data transmission in the target cell according to the first indication information sent by the UE.

[0202] Specifically, if it is based on RACH-based, after the UE completes the downlink synchronization, it reports the first indication information to the base station based on the timing of the source satellite. Optionally, one way is that after receiving the first indication information reported by the UE, the base station determines whether the UE can perform uplink and downlink transmission according to the timing of the target satellite (for example, perform the RACH process) according to interference and other conditions. If the UE receives the second indication information sent by the base station, instructing the UE to perform the random access process, the UE performs the RACH process according to the timing of the target satellite and obtains the TA. The UE can start to apply the timing and TA of the target satellite from this time, or start to apply after receiving the second indication information sent by the network (instructing the UE to access the target satellite), or, after obtaining the TA, start to apply at a specified time (for example, t-service). Another way is that after sending the indication information, the UE applies the timing of the target satellite to trigger the RACH and obtain the TA. The UE can start to apply the timing and TA of the target satellite from this time, or, after obtaining the TA, start to apply at a specified time point (which can be an agreed time or a time pre-configured by the network) (for example, t-service).

[0203] If it is the case without RACH, after the UE performs downlink synchronization and calculates the TA of the target satellite based on the auxiliary information configured by the base station, the UE reports to the base station based on the timing of the source satellite. After receiving the reporting information from the UE, the base station decides whether the UE can apply the timing and TA of the target satellite for uplink and downlink transmission based on interference and other conditions. If the UE receives a message confirmed by the network, the UE can apply the timing and TA of the target satellite from this point on, or start applying it at a specified time point (such as t-service). Another way is that after sending the auxiliary information, the UE applies the timing and TA of the target satellite without waiting for network confirmation.

[0204] If it is the case without RACH, after the UE completes downlink synchronization and calculates the TA of the target satellite based on the auxiliary information configured by the base station, the UE reports to the target satellite, which means that the timing and TA of the target satellite are reported to the base station. Optionally, after receiving the report information from the UE, the base station determines that the UE has accessed the target satellite, stops scheduling the UE on the source satellite, and starts scheduling the UE through the target satellite. Optionally, the target satellite feeds back confirmation information to the UE. The UE can perform data transmission on the target satellite after reporting the indication information, or it can perform data transmission on the target satellite after receiving the confirmation information from the network side (for example, the base station). Specifically, the indication information can be a cell radio network temporary identifier (English: Radio Network Temporary Identifier, abbreviated as: C-RNTI), or it can be the UE's SAE temporary mobile station identifier (English: SAE Temporary Mobile Station Identifier, abbreviated as: S-TMSI).

[0205] The following is a detailed description of the method of applying the target satellite timing in the time period from the start of the target satellite service to the end of the source satellite service for the soft satellite switching scenario.

[0206] The embodiment of the present application provides a method for applying target satellite timing, and the execution subject of the method for applying target satellite timing is a terminal UE; the method for applying target satellite timing provided by the embodiment of the present application includes the following steps:

[0207] Sending first indication information to a base station, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

[0208] The UE sends first indication information to the base station, indicating that the UE has acquired synchronization with the target satellite.

[0209] Optionally, the first indication information includes any one of the following:

[0210] Instructing the UE to acquire downlink synchronization of the target satellite;

[0211] Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite;

[0212] Instruct the UE to acquire uplink synchronization of the target satellite.

[0213] In an embodiment of the present application, by sending a first indication message to the base station, the UE is indicated to have obtained the downlink synchronization and / or uplink synchronization of the target satellite. Specifically, obtaining the downlink synchronization of the target satellite means obtaining the downlink timing of the target satellite, and obtaining the uplink synchronization of the target satellite means obtaining the TA of the target satellite. Specifically, obtaining the downlink timing of the target satellite means obtaining the downlink timing of transparent forwarding of the base station through the target satellite, and obtaining the TA of the target satellite means obtaining the TA of accessing the base station through the target satellite. In this way, the network (here refers to the base station, which will not be repeated below) knows when the UE has obtained downlink synchronization (here refers to obtaining the downlink timing of the target satellite) and / or uplink synchronization (here including TA). It solves the interference problem that may occur in the softsatellite switch scenario, thereby reducing the scheduling complexity of the network, as well as reducing the receiving complexity and energy consumption of the network.

[0214] Optionally, the sending the first indication information to the base station includes any one of the following:

[0215] When the downlink timing of the target satellite is acquired, sending the first indication information to the base station;

[0216] When the downlink timing of the target satellite and the timing advance TA of the target satellite are acquired, sending the first indication information to the base station;

[0217] When the TA of the target satellite is acquired, the first indication information is sent to the base station.

[0218] In an embodiment of the present application, under what conditions does the UE send which indication, that is, when what conditions are met does the UE send the first indication information to the base station, which can be achieved through at least three of the following methods (or behaviors): Method 1, when the UE obtains the downlink timing of the target satellite, the UE sends the first indication information to the base station, wherein the first indication information is used to indicate that the UE has obtained the downlink synchronization of the target satellite, which here refers to the downlink timing of the target satellite; Method 2, when the UE obtains the downlink timing of the target satellite and the TA of the target satellite, the UE sends the first indication information to the base station, wherein the first indication information is used to indicate that the UE has obtained the downlink synchronization and uplink synchronization of the target satellite, which here refers to the downlink timing of the target satellite and the TA of the target satellite; Method 3, when the UE obtains the TA of the target satellite, the UE sends the first indication information to the base station, wherein the first indication information is used to indicate that the UE has obtained the uplink synchronization, which here refers to the TA of the target satellite.

[0219] Specifically, the first indication information may be sent to the base station in the form of RRC signaling, MAC CE or UCI.

[0220] Optionally, the sending the first indication information to the base station includes:

[0221] Sending the first indication information to the base station via a source satellite; or,

[0222] The first indication information is sent to the base station via the target satellite.

[0223] In the embodiment of the present application, how the UE sends the first indication information to the base station can be implemented in at least two of the following ways: Mode 11, according to the downlink timing of the source satellite and the TA of the source satellite, the first indication information is sent to the base station, specifically, according to the downlink timing and TA of the source satellite accessing the service cell, the first indication information is sent to the base station; Mode 12, according to the downlink timing of the target satellite and the TA of the target satellite, the first indication information is sent to the base station, specifically, according to the downlink timing and TA of the target satellite accessing the service cell, the first indication information is sent to the base station. Therefore, any of the above methods can be used to implement the UE sending the first indication information to the base station.

[0224] Optionally, after sending the first indication information to the base station, the method further includes:

[0225] Receive second indication information; wherein the second indication information includes at least one of the following:

[0226] Instructing the UE whether to apply the downlink timing of the target satellite;

[0227] Indicating whether the UE performs a random access procedure;

[0228] Instructing the UE whether to use the TA of the target satellite for uplink transmission;

[0229] Indicating whether the UE accesses a target satellite;

[0230] designated time;

[0231] The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

[0232] In an embodiment of the present application, after sending the first indication information to the base station, the UE receives the second indication information. Specifically, the UE receives the second indication information sent by the base station, and the second indication information is used to indicate whether the UE applies the downlink timing of the target satellite, whether the UE performs a random access process, whether the UE applies the TA of the target satellite for uplink transmission, whether the UE accesses the target satellite, and indicates at least one of the specified time; the specified time includes at least one of the time when the UE performs the random access process, the time when the UE applies the downlink timing of the target satellite, and the time when the UE applies the TA of the target satellite.

[0233] Specifically, the second indication information may be sent to the UE in the form of RRC signaling, MAC CE or DCI.

[0234] Optionally, the receiving the second indication information includes:

[0235] receiving the second indication information sent by the source satellite; or,

[0236] The second indication information sent by the target satellite is received.

[0237] In an embodiment of the present application, the UE receives the second indication information sent by the base station, which can be achieved through at least two of the following methods: Method 21, receiving the second indication information sent by the base station according to the downlink timing of the source satellite; Method 22, receiving the second indication information sent by the base station according to the downlink timing of the target satellite.

[0238] Optionally, before sending the first target indication information to the base station, the method further includes:

[0239] Receiving information configured by the base station;

[0240] The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

[0241] In an embodiment of the present application, the UE receives information configured by the base station, where the configured information is used to instruct the UE to obtain indication information of uplink synchronization of the target satellite, to indicate the time for the UE to apply the downlink timing of the target satellite, to indicate the time for the UE to apply the downlink timing of the target satellite and the TA of the target satellite, to indicate a preamble resource dedicated to the target satellite, to indicate an uplink reference signal resource dedicated to the source satellite, to indicate an uplink reference signal resource dedicated to the target satellite, and to indicate whether the UE reports the first indication information.

[0242] Among them, the indication information instructing the UE to obtain the uplink synchronization of the target satellite is used to indicate whether the UE obtains the uplink synchronization of the target satellite by performing a random access process, instructing the UE to calculate the TA by itself (calculating the TA based on the propagation delay difference between the source satellite and the target satellite), instructing the UE to obtain the TA by random access, and instructing the UE to obtain the TA by sending SRS.

[0243] Specifically, the information configured by the base station may be sent to the UE via dedicated signaling (eg, an RRC reconfiguration message), or may be configured to the UE in the form of broadcasting.

[0244] Optionally, the method of applying the downlink timing of the target satellite includes:

[0245] After sending first indication information of acquiring downlink synchronization of accessing the serving cell through the target satellite to the base station, applying the downlink timing of the target satellite; or,

[0246] After sending the first indication information to the base station to obtain downlink synchronization of accessing the service cell through the target satellite, and receiving the second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite to perform RACH, the downlink timing of the target satellite is applied.

[0247] Optionally, the manner of applying the downlink timing of the target satellite and the TA of the target satellite includes any one of the following:

[0248] After sending first indication information of acquiring downlink synchronization and uplink synchronization of accessing a serving cell through the target satellite to the base station, applying the downlink timing of the target satellite and the TA of the target satellite;

[0249] After sending first indication information to the base station to obtain downlink synchronization and uplink synchronization of accessing the serving cell through the target satellite, and receiving second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite and the TA of the target satellite, applying the downlink timing of the target satellite and the TA of the target satellite;

[0250] According to the specified time in the second indication information sent by the base station, the downlink timing of the target satellite and the TA of the target satellite are applied.

[0251] In an embodiment of the present application, the method in which the UE applies the downlink timing of the target satellite can be implemented through at least two of the following methods: Method 31, after the UE sends an indication of obtaining downlink synchronization for accessing the service cell through the target satellite (here, the UE sends the first indication information used to indicate that the downlink synchronization for accessing the service cell through the target satellite has been obtained), the UE applies the downlink timing of the target satellite to execute the RACH process (i.e., a random access process); Method 32, after the UE sends an indication of obtaining downlink synchronization for accessing the service cell through the target satellite, and receives information from the base station instructing the UE to apply the downlink timing of the target satellite to execute RACH (here, the UE receives the second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite to execute the random access process), the UE applies the downlink timing of the target satellite to execute the RACH process.

[0252] The way in which the UE applies the downlink timing of the target satellite and the TA of the target satellite can be implemented in at least three of the following ways: Way 41, after the UE sends an indication of obtaining downlink synchronization and uplink synchronization of accessing the service cell through the target satellite (here refers to the first indication information sent by the UE that the downlink synchronization and uplink synchronization of accessing the service cell through the target satellite is obtained), the UE applies the downlink timing of the target satellite and the TA of the target satellite for uplink and downlink transmission; Way 42, after the UE sends an indication of obtaining downlink synchronization and uplink synchronization of accessing the service cell through the target satellite and receives information from the network base station instructing the UE to apply the timing and TA of the target satellite for uplink and downlink transmission (here refers to the second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite and the TA of the target satellite), the UE applies the downlink timing of the target satellite and the TA of the target satellite for uplink and downlink transmission; Way 43, at the time specified by the base station (here refers to the specified time indicated in the second indication information), the UE starts to apply the downlink timing of the target satellite and the TA of the target satellite for uplink and downlink transmission.

[0253] Optionally, the method may further include at least one of the following:

[0254] Triggering a random access process;

[0255] applying the TA of the target satellite;

[0256] Monitoring a physical downlink control channel PDCCH of the target satellite;

[0257] Perform uplink and downlink transmission according to the downlink timing of the target satellite and the TA of the target satellite;

[0258] Restart the timing advance timer TAT;

[0259] Read SIB1;

[0260] Read SIB19.

[0261] In the embodiment of the present application, before the UE applies the downlink timing of the target satellite or applies the downlink timing of the target satellite and the TA of the target satellite, or after the UE applies the downlink timing of the target satellite or applies the downlink timing of the target satellite and the TA of the target satellite, the UE may also perform at least one of the following operations: triggering a random access process, applying the TA of the target satellite, monitoring the physical downlink control channel PDCCH of the target satellite, performing uplink and downlink transmission according to the downlink timing of the target satellite and the TA of the target satellite, restarting the timing advance timer TAT, reading SIB1, and reading SIB19 (obtaining the ephemeris of the target satellite, common TA common timing advance and other configurations). It should be noted that the execution order of the above operations is not specifically limited.

[0262] Optionally, the method further comprises:

[0263] Reporting to the base station whether the capability of obtaining uplink synchronization by not performing a random access process is supported. In an embodiment of the present application, before sending the first indication information to the base station, reporting to the base station whether the capability of obtaining uplink synchronization by not performing a random access process is supported. That is, before sending the first indication information to the base station, the UE sends to the base station information indicating whether the capability of obtaining uplink synchronization with the target satellite by not performing a random access process is supported.

[0264] Specifically, obtaining uplink synchronization by not executing a random access procedure refers to the ability to obtain uplink synchronization with a target satellite by not executing a random access procedure. The ability refers to the ability to obtain uplink synchronization by not executing a random access procedure in an unchanged PCI scenario.

[0265] Optionally, before sending the first target indication information to the base station, the method further includes:

[0266] Stop sending the sounding reference signal SRS in accordance with the downlink timing of the source satellite at a preset time, and after acquiring the downlink timing of the target satellite, send the SRS in accordance with the downlink timing of the target satellite; or,

[0267] After the downlink timing of the target satellite is acquired, the SRS resources configured for the target satellite are sent according to the downlink timing of the target satellite.

[0268] In an embodiment of the present application, before the UE sends the first indication information to the base station, the UE may send a signal in at least two of the following ways: Mode 51, at a preset time (for example, t-start or a specified time), stop sending SRS according to the timing of the source satellite (here refers to the downlink timing), and after obtaining the downlink synchronization of the target satellite (here refers to obtaining the downlink timing of the target satellite), send SRS according to the timing of the target satellite (here refers to the downlink timing of the target satellite); (the UE uses the same set of SRS resources during this period). Mode 52, after obtaining the downlink synchronization of the target satellite (here refers to obtaining the downlink timing of the target satellite), send the SRS resources configured for the target satellite according to the timing of the target satellite (here refers to the downlink timing of the target satellite), and maintain the uplink and downlink transmission of the downlink timing of the source satellite; (configure a separate SRS resource for the target satellite).

[0269] It should be noted that the timing refers to downlink timing, which will not be elaborated below.

[0270] Optionally, before sending the first target indication information to the base station, a method of receiving the TA of the target satellite includes:

[0271] Receive the TA of the target satellite sent by the source satellite; or,

[0272] Receive the TA of the target satellite sent by the target satellite.

[0273] In the embodiment of the present application, the UE may receive the TA of the target satellite in at least two ways: in mode 61, the UE receives the TA of the target satellite sent by the base station according to the downlink timing of the source satellite; in mode 62, the UE receives the TA of the target satellite sent by the base station according to the downlink timing of the target satellite. Specifically, the TA value of the target satellite is received through the source satellite, such as MAC CE; after applying the downlink timing of the target satellite, the UE monitors the downlink transmission at the target satellite, and receives the TA value of the target satellite through the target satellite, such as the TA command sent by the target satellite.

[0274] Therefore, the embodiments of the present application solve the interference problem that may occur in the soft satellite switch scenario and reduce the reception complexity and energy consumption of the network.

[0275] Another embodiment of the present application provides a method for applying target satellite timing. The execution subject of the method for applying target satellite timing is a base station. The method for applying target satellite timing may include the following steps:

[0276] Receive first indication information sent by a UE, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

[0277] The base station instructs the UE to obtain synchronization with the target satellite by receiving the first indication information sent by the UE. In this way, the network knows when the UE has obtained synchronization (here refers to downlink synchronization and / or uplink synchronization), and the network does not need to start monitoring the uplink sent by the UE according to the timing of the source satellite and the target satellite from t-start (here refers to the time when the target satellite starts service), thereby reducing the monitoring complexity and energy consumption of the network. At the same time, it solves the interference problem that may occur in the soft satellite switch scenario, thereby reducing the scheduling complexity of the network.

[0278] Optionally, the first indication information includes any one of the following:

[0279] Instructing the UE to acquire downlink synchronization of the target satellite;

[0280] Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite;

[0281] Instruct the UE to acquire uplink synchronization of the target satellite.

[0282] In an embodiment of the present application, by receiving the first indication information sent by the UE, it is indicated that the UE has obtained the downlink synchronization and / or uplink synchronization of the target satellite. Specifically, obtaining the downlink synchronization of the target satellite means obtaining the downlink timing of the target satellite, and obtaining the uplink synchronization of the target satellite means obtaining the TA of the target satellite. Specifically, obtaining the downlink timing of the target satellite means obtaining the downlink timing of transparent forwarding of the base station through the target satellite, and obtaining the TA of the target satellite means obtaining the TA of accessing the base station through the target satellite. In this way, the network knows when the UE obtains downlink synchronization (including downlink timing here) and / or uplink synchronization (including TA here). The interference problem that may occur in the soft satellite switch scenario is solved, thereby reducing the scheduling complexity of the network, as well as reducing the receiving complexity and energy consumption of the network.

[0283] Optionally, the method comprises any of the following:

[0284] The first indication information is sent to the base station by the UE when the UE obtains the downlink timing of the target satellite;

[0285] The first indication information is sent to the base station by the UE when acquiring the downlink timing of the target satellite and the TA of the target satellite;

[0286] The first indication information is sent to the base station by the UE when acquiring the TA of the target satellite.

[0287] In an embodiment of the present application, the base station receives the first indication information sent by the UE, which can be implemented in at least three of the following ways (or behaviors): Way 1, when the UE obtains the downlink timing of the target satellite, the UE sends the first indication information to the base station, and the base station receives the first indication information sent by the UE in the way 1, wherein the first indication information is used to indicate that the UE has obtained the downlink synchronization of the target satellite, which here refers to the downlink timing of the target satellite; Way 2, when the UE obtains the downlink timing of the target satellite and the TA of the target satellite, the UE sends the first indication information to the base station, and the base station receives the first indication information sent by the UE in the way 2, wherein the first indication information is used to indicate that the UE has obtained the downlink synchronization and uplink synchronization of the target satellite, which here refers to the downlink timing of the target satellite and the TA of the target satellite; Way 3, when the UE obtains the TA of the target satellite, the UE sends the first indication information to the base station, and the base station receives the first indication information sent by the UE in the way 3, wherein the first indication information is used to indicate that the UE has obtained the uplink synchronization, which here refers to the TA of the target satellite.

[0288] Specifically, the first indication information may be sent to the base station in the form of RRC signaling, MAC CE or UCI.

[0289] Optionally, the receiving first indication information sent by the UE includes:

[0290] Receiving first indication information sent by the UE through a source satellite; or,

[0291] The first indication information sent by the UE is received through the target satellite.

[0292] In the embodiment of the present application, how the base station receives the first indication information sent by the UE can be implemented in at least two of the following ways: way 11, receiving the first indication information sent by the UE according to the timing of the source satellite, specifically, receiving the first indication information sent by the UE according to the timing of the source satellite accessing the service cell; way 12, receiving the first indication information sent by the UE according to the timing of the target satellite, specifically, receiving the first indication information sent by the UE according to the timing of the target satellite accessing the service cell. Therefore, the base station can receive the first indication information sent by the UE through any of the above ways.

[0293] Optionally, after receiving the first indication information sent by the UE, the method further includes:

[0294] Sending second indication information to the UE; wherein the second indication information includes at least one of the following:

[0295] Instructing the UE whether to apply the downlink timing of the target satellite;

[0296] Indicating whether the UE performs a random access procedure;

[0297] Instructing the UE whether to use the TA of the target satellite for uplink transmission;

[0298] Indicating whether the UE accesses a target satellite;

[0299] designated time;

[0300] The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

[0301] In an embodiment of the present application, after receiving the first indication information sent by the UE, the base station sends the second indication information to the UE, and the second indication information is used to indicate whether the UE applies the downlink timing of the target satellite, whether the UE performs a random access process, whether the UE applies the TA of the target satellite for uplink transmission, whether the UE accesses the target satellite, and at least one of the specified time; the specified time includes at least one of the time when the UE performs a random access process, the time when the UE applies the downlink timing of the target satellite, and the time when the UE applies the TA of the target satellite. Specifically, the second indication information can be sent to the UE in the form of RRC signaling, MAC CE, or DCI.

[0302] Optionally, the sending the second indication information to the UE includes:

[0303] Sending second indication information to the UE via a source satellite; or,

[0304] Send second indication information to the UE through the target satellite.

[0305] In an embodiment of the present application, the base station sends the second indication information to the UE, which can be implemented in at least two of the following ways: Way 21, the base station sends the second indication information to the UE according to the timing of the source satellite; Way 22, the base station sends the second indication information to the UE according to the timing of the target satellite.

[0306] Optionally, before receiving the first indication information sent by the UE, the method further includes:

[0307] Sending configuration information to the UE;

[0308] The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

[0309] In an embodiment of the present application, a base station sends configuration information to a UE, where the configuration information is used to instruct the UE to obtain indication information of uplink synchronization of a target satellite, a time to instruct the UE to apply the downlink timing of the target satellite, a time to instruct the UE to apply the downlink timing of the target satellite and the TA of the target satellite, a preamble resource dedicated to the target satellite, an uplink reference signal resource dedicated to the source satellite, an uplink reference signal resource dedicated to the target satellite, and an indication of whether the UE reports the first indication information; wherein the indication information instructing the UE to obtain the uplink synchronization of the target satellite includes any one of instructing the UE whether to obtain the uplink synchronization of the target satellite by performing a random access process, instructing the UE to calculate the TA by itself (calculating the TA based on the propagation delay difference between the source satellite and the target satellite), instructing the UE to obtain the TA by random access, and instructing the UE to obtain the TA by sending an SRS.

[0310] Specifically, the information configured by the base station may be sent to the UE via dedicated signaling (eg, an RRC reconfiguration message), or may be configured to the UE in the form of broadcasting.

[0311] Optionally, the method further comprises:

[0312] receiving a report from the UE as to whether it supports a capability of obtaining uplink synchronization in a manner not to perform a random access process.

[0313] In an embodiment of the present application, before receiving the first indication information sent by the UE, the UE reports whether the capability of obtaining uplink synchronization by not executing a random access process is supported, that is, before receiving the first indication information sent by the UE, the base station receives information sent by the UE to indicate whether the capability of obtaining uplink synchronization with the target satellite by not executing a random access process is supported. Specifically, obtaining uplink synchronization by not executing a random access process refers to the capability of obtaining uplink synchronization with the target satellite by not executing a random access process. The capability refers to the capability of obtaining uplink synchronization by not executing a random access process in an unchanged PCI scenario.

[0314] Optionally, the manner of sending the TA of the target satellite to the UE includes:

[0315] Sending the TA of the target satellite to the UE via the source satellite; or,

[0316] The TA of the target satellite is sent to the UE via the target satellite.

[0317] In the embodiment of the present application, the method of sending the TA of the target satellite to the UE by the base station can be implemented in at least two of the following methods: method 31, the base station sends the TA of the target satellite to the UE according to the timing of the source satellite; method 32, the UE sends the TA of the target satellite to the UE according to the timing of the target satellite. Specifically, the TA value of the target satellite is sent through the source satellite, such as MAC CE; after applying the downlink timing of the target satellite, the UE monitors the downlink transmission on the target satellite, the base station sends the TA value of the target satellite through the target satellite, and the UE receives the TA value of the target satellite through the target satellite, such as the TA command sent by the target satellite.

[0318] Therefore, the embodiments of the present application solve the interference problem that may occur in the soft satellite switch scenario and reduce the reception complexity and energy consumption of the network.

[0319] The following describes in detail the method of applying target satellite timing through a specific embodiment.

[0320] Exemplary embodiment 1 (for a scenario in which a random access process is performed by means of RACH, and the overall process of applying the method for timing the target satellite)

[0321] See also Figure 2 As shown, Figure 2 The interactive diagram of the method for applying target satellite timing provided by the embodiment of the present application. The method for applying target satellite timing provided by the embodiment includes the following steps:

[0322] Step 0. The network (here refers to the base station, i.e., gNB, which will not be repeated below) configures information (the information configured here includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, the time instructing the UE to apply the downlink timing of the target satellite, the time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, the preamble code preamble resources dedicated to the target satellite, the uplink reference signal resources dedicated to the source satellite, the uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information). The configured information can be broadcast through system information (for example, broadcast in SIB19) or sent to the UE through dedicated signaling.

[0323] Step 1. The UE obtains downlink synchronization by reading the SSB sent by the target satellite, that is, obtains the downlink timing of the target satellite, but it is not applied at this time.

[0324] Step 2. The UE indicates to the network that the UE has acquired downlink synchronization to the serving cell through the target satellite according to the downlink timing of the source satellite and the TA reporting indication information (herein, the first indication information).

[0325] Alternatively, if in step 0, the network configures the UE to report indication information of the synchronization indication of the target satellite (ie, the information configuring the UE by the network includes an indication of whether the UE reports the first indication information), the UE executes step 2, otherwise step 2 is not executed.

[0326] Step 3 (optional). The UE receives the indication information from the network (here the second indication information). The process is executed according to the timing of the source satellite. The indication information is used to indicate whether the UE is allowed to execute the RACH process according to the timing of the target satellite. For example, the network indicates that the UE can use the timing of the target satellite to send uplink signals.

[0327] Step 4. If step 3 is present (i.e., if step 3 is executed), the UE applies the timing of the target satellite to perform the RACH process after receiving the network's indication information; otherwise, the UE applies the timing of the target satellite to perform the RACH process after obtaining downlink synchronization through the report in step 2. Through this step, the UE obtains the TA of the target satellite.

[0328] Step 5 (optional). The UE receives indication information from the network (here, the second indication information), where the indication information is used to instruct the UE to start applying the downlink timing and TA of the target satellite.

[0329] Step 6. If step 5 is performed (i.e., if step 5 is executed), the UE starts to apply the downlink timing and TA of the target satellite after receiving the indication information from the network. Otherwise, after the UE obtains the TA of the target satellite, it immediately starts to apply the downlink timing and TA of the target satellite. Or at a specified time (for example, when the source satellite stops serving t-service), it starts to apply the downlink timing and TA of the target satellite.

[0330] Among them, UE applying the downlink timing and TA of the target satellite means that the UE performs uplink and downlink transmission and measurement according to the downlink timing and TA of the target satellite; in addition, when the UE starts to apply the downlink timing and TA of the target satellite, it no longer maintains the downlink timing and TA of the source satellite.

[0331] In addition, the above steps 3 and 4 can be: Step 3 (optionally). The UE receives indication information from the network. The process is performed according to the timing of the source satellite. The indication information is used to indicate whether the UE is allowed to send an uplink reference signal according to the timing of the target satellite, such as a sounding reference signal (English: Sounding Reference Signal, abbreviated as: SRS).

[0332] Wherein, two sets of SRS resources may be configured for the UE, one set is sent according to the timing of the source satellite, and the other set is sent according to the timing of the target satellite. Step 3 refers to whether the latter set of SRS resources is allowed to be sent according to the timing of the target satellite; or,

[0333] It is assumed that after the target satellite starts to provide service, the terminal (UE) stops sending SRS according to the timing of the source satellite. After the terminal obtains downlink synchronization, it sends SRS according to the timing of the target satellite. Step 3 refers to whether to allow the SRS resource to be sent according to the timing of the target satellite;

[0334] Step 4. If step 3 is performed (i.e., if step 3 is executed), the UE applies the timing of the target satellite to send SRS after receiving the indication information of the network; otherwise, the UE can apply the timing of the target satellite to send SRS after obtaining downlink synchronization in the report in step 2. Through this step, the UE obtains the TA of the target satellite.

[0335] Exemplary embodiment 2 (for the scenario of using the method of target satellite timing without RACH, that is, without performing the random access process)

[0336] See also Figure 3 As shown, Figure 3 This is an interactive diagram of a method for applying target satellite timing provided by another embodiment of the present application. The method for applying target satellite timing provided by this embodiment includes the following steps:

[0337] Step 0. Network configuration information (the information configured here includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information). The configured information can be broadcast through system information (for example, broadcast in SIB19) or sent to the UE through dedicated signaling.

[0338] Step 1. The UE obtains downlink synchronization by reading the SSB sent by the target satellite, that is, obtains the timing of the target satellite. The TA of the target satellite is calculated based on one or more of the UE position, the ephemeris of the source satellite, the ephemeris of the target satellite, and the N_TA configured by the network. At this time, the UE does not apply the downlink timing and TA of the target satellite.

[0339] Step 2. The UE indicates to the network that the UE has acquired downlink synchronization and uplink synchronization of the serving cell through the target satellite according to the downlink timing of the source satellite and the TA reporting indication information (herein, the first indication information). Specifically, the indication information may be indicated by 1 bit.

[0340] Optionally, if in step 0, the network configures the UE to report indication information of the synchronization indication of the target satellite, the UE executes step 2, otherwise step 2 is not executed.

[0341] Alternatively, the UE indicates to the network that the UE has acquired downlink synchronization and uplink synchronization of the serving cell through the target satellite according to the downlink timing and TA reporting indication information of the target satellite. The indication information may be information such as the UE's C-RNTI, S-TMSI, demodulation reference signal (DMRS), SRS or Preamble. This is a form of implicit indication. If the target satellite receives the indication information, it is considered that the terminal (UE) has acquired the uplink synchronization of the target satellite.

[0342] Step 3 (optional). The UE receives indication information from the network (here, the second indication information), where the indication information is used to instruct the UE to start applying the downlink timing and TA of the target satellite.

[0343] Step 4 (optional). If step 3 is performed (i.e., if step 3 is executed), the UE starts to apply the downlink timing and TA of the target satellite after receiving the indication information from the network; otherwise, after the UE obtains the TA of the target satellite, it immediately starts to apply the downlink timing and TA of the target satellite. Alternatively, when the source satellite stops serving (or at a specified time), the downlink timing and TA of the target satellite starts to be applied. In addition, when the UE starts to apply the downlink timing and TA of the target satellite, the downlink timing and TA of the source satellite are no longer maintained.

[0344] Exemplary embodiment 3 (based on embodiments 1 and 2, further refining the process of UE reporting indication information (herein, first indication information) and the network instructing the UE to apply downlink synchronization or downlink synchronization and uplink synchronization of the target satellite)

[0345] The method for applying target satellite timing provided in this embodiment includes the following steps:

[0346] Step 1. The terminal (UE) sends an indication to the network that downlink synchronization or uplink-downlink synchronization (i.e., downlink synchronization and uplink synchronization) of accessing the service cell through the target satellite is obtained (here, it means that the UE sends a first indication information to the base station that downlink synchronization of accessing the service cell through the target satellite is obtained or the UE sends a first indication information to the base station that downlink synchronization and uplink synchronization of accessing the service cell through the target satellite are obtained)

[0347] The indication may be reported to the network via an RRC message, a MAC CE or a UCI;

[0348] The terminal may send the indication according to the downlink timing and TA of the source satellite. Alternatively, if the indication is in the without RACH mode, the terminal may also send the indication to the network according to the acquired downlink timing and TA of the target satellite.

[0349] The specific implementation of the indication information (herein, the first indication information) may be: Option 1 indicates that the UE has completed downlink synchronization or uplink and downlink synchronization through one indication information (for example, one bit), and Option 2 indicates that the UE has completed downlink synchronization or uplink and downlink synchronization through two indication information (for example, two bits are used to indicate respectively). Specifically:

[0350] Option 1: Before step 1, the UE reports whether it supports the capability of obtaining uplink synchronization with the target satellite by means of without RACH, and if the UE supports the without RACH, the UE shall obtain uplink synchronization with the target satellite by means of without RACH by default. If the UE supporting this capability reports this indication information, the network considers that the UE has completed downlink synchronization and uplink synchronization with the target satellite. Otherwise, the network considers that the UE has completed downlink synchronization with the target satellite.

[0351] Option 2: The UE reports indication information 1, and the network considers that the UE has completed downlink synchronization and uplink synchronization with the target satellite. The UE reports indication information 2, and the network considers that the UE has completed downlink synchronization with the target satellite. Indication information 1 and indication information 2 are two different first indication information in Option 2.

[0352] Step 2: The terminal receives indication information (herein referred to as second indication information) sent by the network, indicating whether the target satellite can be used to send uplink and downlink messages at regular intervals.

[0353] The network may provide the UE with the following information (hereinafter referred to as the second indication information):

[0354] Dedicated signaling, such as RRC message, MAC CE or DCI;

[0355] Broadcast method, for example, the network will broadcast an instruction message to the terminals that have completed step 1;

[0356] The terminal may receive the indication (herein, the second indication information) according to the timing of the source satellite. Alternatively, if the terminal receives the indication (herein, the second indication information) according to the downlink timing of the target satellite and the reporting information sent by the TA in step 1 (herein, the first indication information), the terminal may also receive the indication (herein, the second indication information) according to the timing of the target satellite in step 2.

[0357] The specific implementation of the indication information (here, the second indication information) is as follows: Option 1 is indicated by one indication information (for example, one bit), and Option 2 is indicated by two indication information respectively (for example, indicated by two bits respectively). Specifically:

[0358] Option 1: If the UE reports the indication information of step 1 after completing downlink synchronization, then the UE receives the indication information sent by the network in step 2, and the UE believes that the timing of the target satellite can be applied to perform the RACH process; if the UE reports the indication information of step 1 after completing downlink synchronization and uplink synchronization, then the UE receives the indication information sent by the network in step 2, and the UE believes that the downlink timing and TA of the target satellite can be applied for uplink and downlink transmission.

[0359] Option 2: The UE receives indication information A, and the UE believes that the timing of the target satellite can be used to perform the RACH process. The UE receives indication information B, and the UE believes that the down timing and TA of the target satellite can be used for uplink and downlink transmission. Indication information A and indication information B are two different second indication information in Option 2.

[0360] In addition, the indication information (here the second indication information) may also carry the time information in which the network instructs the UE to perform the RACH process or apply the downlink timing of the target satellite and the TA for uplink and downlink transmission, such as the Universal Time Coordinated (UTC) time, or how long it will take to execute.

[0361] Whether the UE reports the indication information (here, the first indication information) is based on the network configuration and is notified through broadcast or dedicated signaling.

[0362] Exemplary Embodiment 4 (Further refining the process in which the network instructs the UE whether to obtain uplink synchronization of the target satellite by executing RACH)

[0363] The method for applying target satellite timing provided in this embodiment includes the following steps:

[0364] The UE reports to the network whether it supports the capability of obtaining uplink synchronization with the target satellite without RACH.

[0365] The network instructs the UE whether to obtain uplink synchronization of the target satellite by executing RACH. The indication information (here refers to the indication information in the configuration information) can be broadcast through system information (for example, broadcast in SIB19) or sent to the UE through dedicated signaling.

[0366] If the network is configured to obtain uplink synchronization with the target satellite in a without RACH manner, and if the UE supports the method of obtaining uplink synchronization with the target satellite in a without RACH manner, the UE obtains uplink synchronization with the target satellite in a without RACH manner; If the network is configured to obtain uplink synchronization with the target satellite in a without RACH manner, and if the UE does not support the method of obtaining uplink synchronization with the target satellite in a without RACH manner, the UE obtains uplink synchronization with the target satellite in a RACH-based manner;

[0367] If the network is not configured to obtain uplink synchronization with the target satellite in a without RACH manner, the UE obtains uplink synchronization with the target satellite in a RACH-based manner.

[0368] Therefore, through any of the above embodiments, the interference problem that may occur in the soft satellite switch scenario is solved, and the reception complexity and energy consumption of the network are reduced.

[0369] It should be noted that the specific implementation process of the method for applying target satellite timing with UE or base station as the execution subject can be referred to Figure 2-Figure 3 The specific implementation process of the illustrated embodiment and Embodiments 3 to 5 will not be described in detail here.

[0370] Another embodiment of the present application provides a method for applying target satellite timing, the method comprising:

[0371] If the RACH-based uplink synchronization method is adopted, the terminal stops TAT ​​in t-service.

[0372] If the RACH-based uplink synchronization method is adopted, the terminal starts or restarts TAT ​​when receiving the TA command.

[0373] If the uplink synchronization method without RACH is adopted, the terminal performs at least one of the following in t-service: starts or restarts TAT, and applies N_TA (timing advance parameter configured by the network).

[0374] If the uplink synchronization method without RACH is adopted, the terminal performs at least one of the following at t-start: starts or restarts TAT, and applies N_TA (a timing advance parameter configured by the network).

[0375] After acquiring the downlink synchronization of the target satellite, the UE performs at least one of the following: starting or restarting T430 (uplink synchronization timer), and the RRC layer notifies the MAC layer that uplink synchronization has been acquired.

[0376] Figure 4 A schematic diagram of the structure of the device for applying target satellite timing provided in the embodiment of the present application, such as Figure 4 As shown, the device for applying target satellite timing provided by this embodiment is executed by the terminal UE. Then the device for applying target satellite timing provided by this embodiment includes: a transceiver 400, which is used to receive and send data under the control of a processor 410.

[0377] Among them, Figure 4In the embodiment, the bus architecture may include any number of interconnected buses and bridges, specifically one or more processors represented by processor 410 and various circuits of memory represented by memory 420 are linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface. The transceiver 400 may be a plurality of components, namely, a transmitter and a receiver, providing a unit for communicating with various other devices on a transmission medium, such as a wireless channel, a wired channel, an optical cable, and the like. The user interface 430 may also be an interface capable of externally and internally connecting required devices, and the connected devices include but are not limited to a keypad, a display, a speaker, a microphone, a joystick, and the like.

[0378] The processor 410 is responsible for managing the bus architecture and general processing, and the memory 420 can store data used by the processor 410 when performing operations.

[0379] Optionally, the processor 410 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or a complex programmable logic device (CPLD), and the processor may also adopt a multi-core architecture.

[0380] In this embodiment, the memory 420 is used to store a computer program; the transceiver 400 is used to send and receive data under the control of the processor; the processor 410 is used to read the computer program in the memory and perform the following operations:

[0381] Sending first indication information to a base station, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

[0382] Optionally, the first indication information includes any one of the following:

[0383] Instructing the UE to acquire downlink synchronization of the target satellite;

[0384] Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite;

[0385] Instruct the UE to acquire uplink synchronization of the target satellite.

[0386] Optionally, the processor 410 is configured to, when sending the first indication information to the base station, specifically include any of the following items:

[0387] When the downlink timing of the target satellite is acquired, sending the first indication information to the base station;

[0388] When the downlink timing of the target satellite and the timing advance TA of the target satellite are acquired, sending the first indication information to the base station;

[0389] When the TA of the target satellite is acquired, the first indication information is sent to the base station.

[0390] Optionally, the processor 410 is configured to, when sending the first indication information to the base station, specifically include any of the following items:

[0391] Sending the first indication information to the base station via a source satellite; or,

[0392] The first indication information is sent to the base station via the target satellite.

[0393] Optionally, the processor 410 is configured to, after sending the first indication information to the base station, perform the following operations:

[0394] Receive second indication information; wherein the second indication information includes at least one of the following:

[0395] Instructing the UE whether to apply the downlink timing of the target satellite;

[0396] Indicating whether the UE performs a random access procedure;

[0397] Instructing the UE whether to use the TA of the target satellite for uplink transmission;

[0398] Indicating whether the UE accesses a target satellite;

[0399] designated time;

[0400] The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

[0401] Optionally, the processor 410 is configured to, when receiving the second indication information sent by the base station, specifically include:

[0402] receiving the second indication information sent by the source satellite; or,

[0403] The second indication information sent by the target satellite is received.

[0404] Optionally, the processor 410 is configured to, before sending the first indication information to the base station, perform the following operations:

[0405] Receiving information configured by the base station;

[0406] The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

[0407] Optionally, the processor 410 is configured to, when applying the downlink timing of the target satellite, specifically include the following:

[0408] After sending first indication information of acquiring downlink synchronization of accessing the serving cell through the target satellite to the base station, applying the downlink timing of the target satellite; or,

[0409] After sending the first indication information to the base station to obtain the downlink synchronization of accessing the service cell through the target satellite, and receiving the second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite to perform a random access process, the downlink timing of the target satellite is applied.

[0410] Optionally, the processor 410 is configured to, when applying the downlink timing of the target satellite and the TA of the target satellite, specifically include any of the following items:

[0411] After sending first indication information of acquiring downlink synchronization and uplink synchronization of accessing a serving cell through the target satellite to the base station, applying the downlink timing of the target satellite and the TA of the target satellite;

[0412] After sending first indication information to the base station to obtain downlink synchronization and uplink synchronization of accessing the serving cell through the target satellite, and receiving second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite and the TA of the target satellite, applying the downlink timing of the target satellite and the TA of the target satellite;

[0413] According to the specified time in the second indication information sent by the base station, the downlink timing of the target satellite and the TA of the target satellite are applied.

[0414] Optionally, the processor 410 is further configured to perform at least one of the following operations:

[0415] Triggering a random access process;

[0416] applying the TA of the target satellite;

[0417] Monitoring a physical downlink control channel PDCCH of the target satellite;

[0418] Perform uplink and downlink transmission according to the downlink timing of the target satellite and the TA of the target satellite;

[0419] Restart the timing advance timer TAT;

[0420] Read SIB1;

[0421] Read SIB19.

[0422] Optionally, the processor 410 is further configured to perform the following operations:

[0423] Reporting to the base station whether a capability of obtaining uplink synchronization by not performing a random access process is supported.

[0424] Optionally, the processor 410 is configured to perform the following operations before sending the first indication information to the base station:

[0425] Stop sending the sounding reference signal SRS in accordance with the downlink timing of the source satellite at a preset time, and after acquiring the downlink timing of the target satellite, send the SRS in accordance with the downlink timing of the target satellite; or,

[0426] After the downlink timing of the target satellite is acquired, the SRS resources configured for the target satellite are sent according to the downlink timing of the target satellite.

[0427] Optionally, the processor 410 is configured to, before sending the first indication information to the base station, when receiving the TA of the target satellite, specifically include:

[0428] Receive the TA of the target satellite sent by the source satellite; or,

[0429] Receive the TA of the target satellite sent by the target satellite.

[0430] It should be noted here that the device for applying target satellite timing provided by the present application can implement all the method steps implemented by the method embodiment of the first aspect above and its specific implementation process can be referred to Figure 2-Figure 3 The illustrated embodiment and Embodiments 3 to 5 can achieve the same technical effect, and the parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be described in detail here.

[0431] Another embodiment of the present application provides an apparatus for applying target satellite timing. The apparatus for applying target satellite timing provided by this embodiment is executed by a UE. The apparatus for applying target satellite timing provided by this embodiment includes:

[0432] The sending unit is used to send first indication information to the base station, where the first indication information is used to instruct the UE to acquire synchronization with the target satellite.

[0433] Optionally, the first indication information includes any one of the following:

[0434] Instructing the UE to acquire downlink synchronization of the target satellite;

[0435] Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite;

[0436] Instruct the UE to acquire uplink synchronization of the target satellite.

[0437] Optionally, the sending unit is specifically configured to perform any of the following:

[0438] When the downlink timing of the target satellite is acquired, sending the first indication information to the base station;

[0439] When the downlink timing of the target satellite and the timing advance TA of the target satellite are acquired, sending the first indication information to the base station;

[0440] When the TA of the target satellite is acquired, the first indication information is sent to the base station.

[0441] Optionally, the sending unit is specifically configured to:

[0442] Sending the first indication information to the base station via a source satellite; or,

[0443] The first indication information is sent to the base station via the target satellite.

[0444] Optionally, the device further includes: a receiving unit; the receiving unit is configured to receive second indication information after sending the first indication information to the base station; wherein the second indication information includes at least one of the following:

[0445] Instructing the UE whether to apply the downlink timing of the target satellite;

[0446] Indicating whether the UE performs a random access procedure;

[0447] Instructing the UE whether to use the TA of the target satellite for uplink transmission;

[0448] Indicating whether the UE accesses a target satellite;

[0449] designated time;

[0450] The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

[0451] Optionally, the receiving unit is specifically configured to:

[0452] receiving the second indication information sent by the source satellite; or,

[0453] The second indication information sent by the target satellite is received.

[0454] Optionally, the receiving unit is further used for:

[0455] Before sending the first target indication information to the base station, receiving information configured by the base station;

[0456] The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

[0457] Optionally, the device further comprises an application unit; the application unit is configured to:

[0458] The downlink timing of the target satellite is applied, or the downlink timing of the target satellite and the TA of the target satellite are applied.

[0459] Optionally, the application unit is specifically configured to perform the following operations:

[0460] After sending first indication information of acquiring downlink synchronization of accessing the serving cell through the target satellite to the base station, applying the downlink timing of the target satellite; or,

[0461] After sending the first indication information to the base station to obtain downlink synchronization of accessing the service cell through the target satellite, and receiving the second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite to perform RACH, the downlink timing of the target satellite is applied.

[0462] Optionally, the application unit is specifically configured to perform any of the following:

[0463] After sending first indication information of acquiring downlink synchronization and uplink synchronization of accessing a serving cell through the target satellite to the base station, applying the downlink timing of the target satellite and the TA of the target satellite;

[0464] After sending first indication information to the base station to obtain downlink synchronization and uplink synchronization of accessing the serving cell through the target satellite, and receiving second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite and the TA of the target satellite, applying the downlink timing of the target satellite and the TA of the target satellite;

[0465] According to the specified time in the second indication information sent by the base station, the downlink timing of the target satellite and the TA of the target satellite are applied.

[0466] Optionally, the device further comprises a processing unit; the processing unit is configured to perform at least one of the following:

[0467] Triggering a random access process;

[0468] applying the TA of the target satellite;

[0469] Monitoring a physical downlink control channel PDCCH of the target satellite;

[0470] Perform uplink and downlink transmission according to the downlink timing of the target satellite and the TA of the target satellite;

[0471] Restart the timing advance timer TAT;

[0472] Read SIB1;

[0473] Read SIB19.

[0474] Optionally, the sending unit is further used to: before sending the first indication information to the base station, report to the base station whether the ability to obtain uplink synchronization by not performing a random access process is supported.

[0475] Optionally, the sending unit is further used to:

[0476] Before sending the first target indication information to the base station, stop sending the sounding reference signal SRS in a downlink timing manner of the source satellite at a preset time, and after acquiring the downlink timing of the target satellite, send the SRS in accordance with the downlink timing of the target satellite; or,

[0477] After the downlink timing of the target satellite is acquired, the SRS resources configured for the target satellite are sent according to the downlink timing of the target satellite.

[0478] Optionally, the receiving unit is further used to: before sending the first target indication information to the base station, receive the TA of the target satellite;

[0479] Wherein, the receiving unit is specifically used for:

[0480] Receive the TA of the target satellite sent by the source satellite; or,

[0481] Receive the TA of the target satellite sent by the target satellite.

[0482] It should be noted here that the device for applying target satellite timing provided by the present application can implement all the method steps implemented by the method embodiment of the first aspect above and its specific implementation process can be referred to Figure 2-Figure 3 The illustrated embodiment and Embodiments 3 to 5 can achieve the same technical effect, and the parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be described in detail here.

[0483] Figure 5 A schematic diagram of a device for applying target satellite timing according to another embodiment of the present application is shown in FIG. Figure 5 As shown, the device for applying target satellite timing provided by this embodiment is executed by a base station, and the device for applying target satellite timing provided by this embodiment includes: a transceiver 500, which is used to receive and send data under the control of a processor 510.

[0484] Among them, Figure 5 In the embodiment, the bus architecture may include any number of interconnected buses and bridges, specifically linking together various circuits of one or more processors represented by processor 510 and memory represented by memory 520. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface. The transceiver 500 may be a plurality of components, namely, a transmitter and a receiver, providing a unit for communicating with various other devices on a transmission medium, which transmission medium may include a wireless channel, a wired channel, an optical cable, and the like. The processor 510 is responsible for managing the bus architecture and general processing, and the memory 520 may store data used by the processor 510 when performing operations.

[0485] The processor 510 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or a complex programmable logic device (CPLD). The processor may also adopt a multi-core architecture.

[0486] In this embodiment, the memory 520 is used to store a computer program; the transceiver 500 is used to send and receive data under the control of the processor; and the processor 510 is used to read the computer program in the memory and perform the following operations:

[0487] Receive first indication information sent by a UE, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

[0488] Optionally, the first indication information includes any one of the following:

[0489] Instructing the UE to acquire downlink synchronization of the target satellite;

[0490] Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite;

[0491] Instruct the UE to acquire uplink synchronization of the target satellite.

[0492] Optionally, the first indication information is sent to the base station by the UE when acquiring the downlink timing of the target satellite; or,

[0493] The first indication information is sent to the base station by the UE when the UE obtains the downlink timing of the target satellite and the TA of the target satellite; or,

[0494] The first indication information is sent to the base station by the UE when acquiring the TA of the target satellite.

[0495] Optionally, the processor is configured to, when receiving first indication information sent by the UE, specifically include:

[0496] Receiving first indication information sent by the UE through a source satellite; or,

[0497] The first indication information sent by the UE is received through the target satellite.

[0498] Optionally, the processor is configured to, after receiving the first indication information sent by the UE, perform the following operations:

[0499] Sending second indication information to the UE; wherein the second indication information includes at least one of the following:

[0500] Instructing the UE whether to apply the downlink timing of the target satellite;

[0501] Indicating whether the UE performs a random access procedure;

[0502] Instructing the UE whether to use the TA of the target satellite for uplink transmission;

[0503] Indicating whether the UE accesses a target satellite;

[0504] designated time;

[0505] The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

[0506] Optionally, the processor is configured to, when sending the second indication information to the UE, specifically include:

[0507] Sending second indication information to the UE via a source satellite; or,

[0508] Send second indication information to the UE through the target satellite.

[0509] Optionally, the processor is configured to, before receiving the first indication information sent by the UE, perform the following operations:

[0510] Sending configuration information to the UE;

[0511] The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

[0512] Optionally, the processor is further configured to perform the following operations:

[0513] receiving a report from the UE as to whether it supports a capability of obtaining uplink synchronization in a manner not to perform a random access process.

[0514] Optionally, the processor is configured to, when sending the TA of the target satellite to the UE, specifically include:

[0515] Sending the TA of the target satellite to the UE via the source satellite; or,

[0516] The TA of the target satellite is sent to the UE via the target satellite.

[0517] It should be noted here that the device for applying target satellite timing provided in the present application can implement all the method steps implemented by the method embodiment of the second aspect above and its specific implementation process can be referred to Figure 2-Figure 3The illustrated embodiment and Embodiments 3 to 5 can achieve the same technical effect, and the parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be described in detail here.

[0518] Another embodiment of the present application provides an apparatus for applying target satellite timing. The apparatus for applying target satellite timing provided by the embodiment of the present application is executed by a base station. The apparatus for applying target satellite timing provided by the embodiment includes:

[0519] The receiving unit is used to receive first indication information sent by the UE, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

[0520] Optionally, the first indication information includes any one of the following:

[0521] Instructing the UE to acquire downlink synchronization of the target satellite;

[0522] Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite;

[0523] Instruct the UE to acquire uplink synchronization of the target satellite.

[0524] Optionally, the first indication information is sent to the base station by the UE when acquiring the downlink timing of the target satellite;

[0525] The first indication information is sent to the base station by the UE when acquiring the downlink timing of the target satellite and the TA of the target satellite;

[0526] The first indication information is sent to the base station by the UE when acquiring the TA of the target satellite.

[0527] Optionally, the receiving unit is specifically configured to:

[0528] Receiving first indication information sent by the UE through a source satellite; or,

[0529] The first indication information sent by the UE is received through the target satellite.

[0530] Optionally, the device further includes: a sending unit; a sending unit, configured to send second indication information to the UE after receiving the first indication information sent by the UE; wherein the second indication information includes at least one of the following:

[0531] Instructing the UE whether to apply the downlink timing of the target satellite;

[0532] Indicating whether the UE performs a random access procedure;

[0533] Instructing the UE whether to use the TA of the target satellite for uplink transmission;

[0534] Indicating whether the UE accesses a target satellite;

[0535] designated time;

[0536] The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

[0537] Optionally, the sending unit is specifically configured to:

[0538] Sending second indication information to the UE via a source satellite; or,

[0539] Send second indication information to the UE through the target satellite.

[0540] Optionally, the sending unit is further configured to: send configuration information to the UE before receiving the first indication information sent by the UE;

[0541] The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

[0542] Optionally, the receiving unit is further used for:

[0543] receiving a report from the UE as to whether it supports a capability of obtaining uplink synchronization in a manner not to perform a random access process.

[0544] Optionally, the sending unit is specifically configured to:

[0545] Sending the TA of the target satellite to the UE via the source satellite; or,

[0546] The TA of the target satellite is sent to the UE via the target satellite.

[0547] It should be noted here that the device for applying target satellite timing provided in the present application can implement all the method steps implemented by the method embodiment of the second aspect above and its specific implementation process can be referred to Figure 2-Figure 3The illustrated embodiment and Embodiments 3 to 5 can achieve the same technical effect, and the parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be described in detail here.

[0548] It should be noted that the division of units in the embodiments of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation. In addition, each functional unit in each embodiment of the present application may be integrated into a processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0549] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a processor-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) or a processor (processor) to perform all or part of the steps of each embodiment method of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), disk or optical disk and other media that can store program code.

[0550] The embodiment of the present application further provides a non-transitory readable storage medium. The non-transitory readable storage medium stores a computer program, and the computer program is used to enable a processor to execute any of the above method embodiments.

[0551] Among them, the non-transitory readable storage medium can be any available medium or data storage device that can be accessed by the processor, including but not limited to magnetic storage (such as floppy disks, hard disks, magnetic tapes, magneto-optical disks (MO), etc.), optical storage (such as CD, DVD, BD, HVD, etc.), and semiconductor storage (such as ROM, EPROM, EEPROM, non-volatile memory (NANDFLASH), solid-state drive (SSD)), etc.

[0552] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) that contain computer-usable program code.

[0553] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer executable instructions. These computer executable instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0554] These processor executable instructions may also be stored in a processor readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the processor readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0555] These processor-executable instructions may also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable device to implement the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0556] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for applying target satellite timing, characterized in that: The method is performed by a terminal UE, and the method includes: Sending first indication information to a base station, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

2. The method according to claim 1, characterized in that The first indication information includes any of the following: Instructing the UE to acquire downlink synchronization of the target satellite; Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite; Instruct the UE to acquire uplink synchronization of the target satellite.

3. The method according to claim 1, characterized in that The sending the first indication information to the base station includes any one of the following: When the downlink timing of the target satellite is acquired, sending the first indication information to the base station; When the downlink timing of the target satellite and the timing advance TA of the target satellite are acquired, sending the first indication information to the base station; When the TA of the target satellite is acquired, the first indication information is sent to the base station.

4. The method according to any one of claims 1 to 3, characterized in that: The sending first indication information to the base station includes: Sending the first indication information to the base station via a source satellite; or, The first indication information is sent to the base station via the target satellite.

5. The method according to claim 1, characterized in that After sending the first indication information to the base station, the method further includes: Receive second indication information; wherein the second indication information includes at least one of the following: Instructing the UE whether to apply the downlink timing of the target satellite; Indicating whether the UE performs a random access procedure; Instructing the UE whether to use the TA of the target satellite for uplink transmission; Indicating whether the UE accesses a target satellite; designated time; The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

6. The method according to claim 5, characterized in that The receiving the second indication information includes: receiving the second indication information sent by the source satellite; or, The second indication information sent by the target satellite is received.

7. The method according to claim 1, characterized in that Before sending the first target indication information to the base station, the method further includes: Receiving information configured by the base station; The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

8. The method according to any one of claims 1 to 3 or 5, characterized in that: Methods for applying the downlink timing of the target satellite include: After sending first indication information of acquiring downlink synchronization of accessing the serving cell through the target satellite to the base station, applying the downlink timing of the target satellite; or, After sending the first indication information to the base station to obtain the downlink synchronization of accessing the service cell through the target satellite, and receiving the second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite to perform a random access process, the downlink timing of the target satellite is applied.

9. The method according to any one of claims 1 to 3 or 5, characterized in that: The method of applying the downlink timing of the target satellite and the TA of the target satellite includes any of the following: After sending first indication information of acquiring downlink synchronization and uplink synchronization of accessing a serving cell through the target satellite to the base station, applying the downlink timing of the target satellite and the TA of the target satellite; After sending first indication information to the base station to obtain downlink synchronization and uplink synchronization of accessing the serving cell through the target satellite, and receiving second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite and the TA of the target satellite, applying the downlink timing of the target satellite and the TA of the target satellite; According to the specified time in the second indication information sent by the base station, the downlink timing of the target satellite and the TA of the target satellite are applied.

10. The method according to claim 9, characterized in that The method may further include at least one of the following: Triggering a random access process; applying the TA of the target satellite; Monitoring a physical downlink control channel PDCCH of the target satellite; Perform uplink and downlink transmission according to the downlink timing of the target satellite and the TA of the target satellite; Restart the timing advance timer TAT; Read SIB1; Read SIB19.

11. The method according to claim 1, characterized in that: The method further comprises: Reporting to the base station whether a capability of obtaining uplink synchronization by not performing a random access process is supported.

12. The method according to claim 1, characterized in that Before sending the first indication information to the base station, the method further includes: Stop sending the sounding reference signal SRS in accordance with the downlink timing of the source satellite at a preset time, and after acquiring the downlink timing of the target satellite, send the SRS in accordance with the downlink timing of the target satellite; or, After the downlink timing of the target satellite is acquired, the SRS resources configured for the target satellite are sent according to the downlink timing of the target satellite.

13. The method according to claim 1, characterized in that Before sending the first target indication information to the base station, the method of receiving the TA of the target satellite includes: Receive the TA of the target satellite sent by the source satellite; or, Receive the TA of the target satellite sent by the target satellite.

14. A method for applying target satellite timing, characterized in that: The method is performed by a base station, and the method includes: Receive first indication information sent by a UE, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

15. The method according to claim 14, characterized in that The first indication information includes any of the following: Instructing the UE to acquire downlink synchronization of the target satellite; Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite; Instruct the UE to acquire uplink synchronization of the target satellite.

16. The method according to claim 14, characterized in that The method comprises any of the following: The first indication information is sent to the base station by the UE when the UE obtains the downlink timing of the target satellite; The first indication information is sent to the base station by the UE when acquiring the downlink timing of the target satellite and the TA of the target satellite; The first indication information is sent to the base station by the UE when acquiring the TA of the target satellite.

17. The method according to any one of claims 14 to 16, characterized in that: The receiving first indication information sent by the UE includes: Receiving first indication information sent by the UE through a source satellite; or, The first indication information sent by the UE is received through the target satellite.

18. The method according to claim 14, characterized in that After receiving the first indication information sent by the UE, the method further includes: Sending second indication information to the UE; wherein the second indication information includes at least one of the following: Instructing the UE whether to apply the downlink timing of the target satellite; Indicating whether the UE performs a random access procedure; Instructing the UE whether to use the TA of the target satellite for uplink transmission; Indicating whether the UE accesses a target satellite; designated time; The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

19. The method according to claim 18, characterized in that The sending the second indication information to the UE includes: Sending second indication information to the UE via a source satellite; or, Send second indication information to the UE through the target satellite.

20. The method according to claim 14, characterized in that Before the receiving the first indication information sent by the UE, the method further includes: Sending configuration information to the UE; The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

21. The method according to claim 14, characterized in that The method further comprises: receiving a report from the UE as to whether it supports a capability of obtaining uplink synchronization in a manner not to perform a random access process.

22. The method according to claim 14, characterized in that The method of sending the TA of the target satellite to the UE includes: Sending the TA of the target satellite to the UE via the source satellite; or, The TA of the target satellite is sent to the UE via the target satellite.

23. A device for using target satellite timing, characterized in that: The device is executed by a UE, and the device includes: The sending unit is used to send first indication information to the base station, where the first indication information is used to instruct the UE to acquire synchronization with the target satellite.

24. A device for using target satellite timing, characterized in that: The device is executed by a base station, and the device includes: The receiving unit is used to receive first indication information sent by the UE, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

25. A device for using target satellite timing, characterized in that: The device is executed by UE, and the device includes a memory, a transceiver, and a processor: a memory for storing a computer program; a transceiver for transmitting and receiving data under the control of the processor; A processor is configured to read the computer program in the memory and perform the following operations: Sending first indication information to a base station, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

26. The device according to claim 25, characterized in that The first indication information includes any of the following: Instructing the UE to acquire downlink synchronization of the target satellite; Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite; Instruct the UE to acquire uplink synchronization of the target satellite.

27. The device according to claim 25, characterized in that The processor is configured to, when sending the first indication information to the base station, specifically include any of the following items: When the downlink timing of the target satellite is acquired, sending the first indication information to the base station; When the downlink timing of the target satellite and the timing advance TA of the target satellite are acquired, sending the first indication information to the base station; When the TA of the target satellite is acquired, the first indication information is sent to the base station.

28. The device according to any one of claims 25 to 27, characterized in that The processor is configured to, when sending the first indication information to the base station, specifically include any of the following items: Sending the first indication information to the base station via a source satellite; or, The first indication information is sent to the base station via the target satellite.

29. The device according to claim 25, characterized in that The processor is configured to, after sending the first indication information to the base station, perform the following operations: Receive second indication information; wherein the second indication information includes at least one of the following: Instructing the UE whether to apply the downlink timing of the target satellite; Indicating whether the UE performs a random access procedure; Instructing the UE whether to use the TA of the target satellite for uplink transmission; Indicating whether the UE accesses a target satellite; designated time; The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

30. The device according to claim 25, characterized in that The processor is configured to, before sending the first indication information to the base station, perform the following operations: Receiving information configured by the base station; The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

31. The device according to any one of claims 25 to 27 or 29, characterized in that The processor is used to specifically include the following when applying the downlink timing of the target satellite: After sending first indication information of acquiring downlink synchronization of accessing a serving cell through the target satellite to the base station, applying the downlink timing of the target satellite; or, After sending the first indication information to the base station to obtain the downlink synchronization of accessing the service cell through the target satellite, and receiving the second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite to perform a random access process, the downlink timing of the target satellite is applied.

32. The device according to any one of claims 25 to 27 or 29, characterized in that The processor is used to, when applying the downlink timing of the target satellite and the TA of the target satellite, specifically include any of the following: After sending first indication information of acquiring downlink synchronization and uplink synchronization of accessing a serving cell through the target satellite to the base station, applying the downlink timing of the target satellite and the TA of the target satellite; After sending first indication information to the base station to obtain downlink synchronization and uplink synchronization of accessing the serving cell through the target satellite, and receiving second indication information sent by the base station to instruct the UE to apply the downlink timing of the target satellite and the TA of the target satellite, applying the downlink timing of the target satellite and the TA of the target satellite; According to the specified time in the second indication information sent by the base station, the downlink timing of the target satellite and the TA of the target satellite are applied.

33. The device according to claim 25, characterized in that The processor is further configured to perform the following operations: Reporting to the base station whether a capability of obtaining uplink synchronization by not performing a random access process is supported.

34. The device according to claim 25, characterized in that The processor is configured to perform the following operations before sending the first indication information to the base station: Stop sending the sounding reference signal SRS in accordance with the downlink timing of the source satellite at a preset time, and after acquiring the downlink timing of the target satellite, send the SRS in accordance with the downlink timing of the target satellite; or, After the downlink timing of the target satellite is acquired, the SRS resources configured for the target satellite are sent according to the downlink timing of the target satellite.

35. The device according to claim 25, characterized in that The processor is configured to, before sending the first indication information to the base station, when receiving the TA of the target satellite, specifically include: Receive the TA of the target satellite sent by the source satellite; or, Receive the TA of the target satellite sent by the target satellite.

36. A device for using target satellite timing, characterized in that: The device is executed by a base station, and includes a memory, a transceiver, and a processor: A memory for storing a computer program; a transceiver for transmitting and receiving data under the control of the processor; and a processor for reading the computer program in the memory and performing the following operations: Receive first indication information sent by a UE, where the first indication information is used to instruct the UE to acquire synchronization with a target satellite.

37. The device according to claim 36, characterized in that The first indication information includes any of the following: Instructing the UE to acquire downlink synchronization of the target satellite; Instructing the UE to acquire downlink synchronization and uplink synchronization of the target satellite; Instruct the UE to acquire uplink synchronization of the target satellite.

38. The device according to claim 36, characterized in that The first indication information is sent to the base station by the UE when the UE obtains the downlink timing of the target satellite; or, The first indication information is sent to the base station by the UE when the UE obtains the downlink timing of the target satellite and the TA of the target satellite; or, The first indication information is sent to the base station by the UE when acquiring the TA of the target satellite.

39. The device according to any one of claims 36 to 38, characterized in that The processor is configured to, when receiving first indication information sent by the UE, specifically include: Receiving first indication information sent by the UE through a source satellite; or, The first indication information sent by the UE is received through the target satellite.

40. The device according to claim 36, characterized in that The processor is configured to, after receiving first indication information sent by the UE, perform the following operations: Sending second indication information to the UE; wherein the second indication information includes at least one of the following: Instructing the UE whether to apply the downlink timing of the target satellite; Indicating whether the UE performs a random access procedure; Instructing the UE whether to use the TA of the target satellite for uplink transmission; Indicating whether the UE accesses a target satellite; designated time; The specified time is used to indicate at least one of the following: the time when the UE performs a random access process, the time when the downlink timing of the target satellite is applied, and the time when the TA of the target satellite is applied.

41. The device according to claim 36, characterized in that The processor is configured to, before receiving first indication information sent by the UE, perform the following operations: Sending configuration information to the UE; The configured information includes at least one of the following: indication information instructing the UE to obtain uplink synchronization of the target satellite, time instructing the UE to apply the downlink timing of the target satellite, time instructing the UE to apply the downlink timing of the target satellite and the TA of the target satellite, preamble resources dedicated to the target satellite, uplink reference signal resources dedicated to the source satellite, uplink reference signal resources dedicated to the target satellite, and indicating whether the UE reports the first indication information.

42. The device according to claim 36, characterized in that The processor is further configured to perform the following operations: receiving a report from the UE as to whether it supports a capability of obtaining uplink synchronization in a manner not to perform a random access process.

43. The device according to claim 36, characterized in that The processor is configured to, when sending the TA of the target satellite to the UE, specifically include: Sending the TA of the target satellite to the UE via the source satellite; or, The TA of the target satellite is sent to the UE via the target satellite.

44. A non-transitory readable storage medium, characterized in that The non-transitory readable storage medium stores a computer program, and the computer program is used to enable a processor to execute the method according to any one of claims 1 to 22.

Images