A method of determining timing advance, a communication device

Abstract

The embodiment of the application provides a method for determining timing advance, and a communication device, which are used for improving the precision of terminal calculating timing advance (TA) and solving the problem of inter-symbol interference (ISI). The method comprises the following steps: a first network device determines a first parameter according to a first time delay compensation value, wherein the first time delay compensation value is a time delay compensation made by the first network device for receiving a signal sent by a terminal, the first parameter is used for indicating a difference value between a round-trip time delay of a feeder link in a non-terrestrial network (NTN) and the first time delay compensation value, and the difference value is used for determining a TA used by the terminal for sending a signal; and the first network device sends the first parameter.

Description

[0001] This application is a divisional application. The original application has the application number 202011105020.7 and the original application date is October 15, 2020. The entire contents of the original application are incorporated herein by reference.

[0002] This application claims priority to Chinese Patent Application No. 202010093795.0, filed on February 14, 2020, with the title “A method for determining timing advance, a communication device”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of communication technology, and in particular to a method and communication device for determining timing advance. Background Technology

[0004] For non-terrestrial networks (NTN) communication, when sending a preamble, the terminal can receive a common timing advance value broadcast by the network device and use the common timing advance value for timing advance (TA) to reduce the impact of round-trip delay between the terminal and the network device on receiving the random access preamble and improve the problem of inter-symbol interference (ISI).

[0005] In practical applications, network devices often compensate for a portion of the round-trip time (RTT) between the terminal and the network device. Therefore, the actual RTT compensation required by the terminal should only be a portion of the common timing advance value. However, in existing technologies, the terminal can only obtain the common timing advance value broadcast by the network device and cannot calculate the accurate timing advance (TA). As a result, the random access preamble still suffers from severe inter-interference signaling (ISI). Summary of the Invention

[0006] This application provides a method and communication device for determining timing advance, which improves the accuracy of the terminal's timing advance calculation and enhances the accuracy of the timing advance.

[0007] In a first aspect, embodiments of this application provide a method for determining a transfer time (TA), comprising: a first network device determining a first parameter based on a first delay compensation value, wherein the first delay compensation value is a delay compensation made by the first network device for a signal transmitted by a receiving terminal, the first parameter being used to indicate the difference between the round-trip delay of the feeder link in a non-terrestrial network (NTN) and the first delay compensation value, the difference being used to determine the TA used by the terminal to transmit the signal; and the first network device transmitting the first parameter.

[0008] In this embodiment, since the first parameter can indicate the difference between the round-trip time delay of the power supply link and the first delay compensation value, when the terminal receives the first parameter and determines the TA based on the first parameter, it takes into account the delay compensation performed by the first network device on the signal sent by the terminal. Therefore, the accuracy of the terminal's calculation of TA can be improved, thereby better improving the ISI problem.

[0009] In one possible implementation, the first parameter is used to indicate the difference between the round-trip delay of the feeder link in the NTN and the first delay compensation value, including: the first parameter being the difference between the round-trip delay of the feeder link in the NTN and the first delay compensation value; or, the first parameter being used to determine the difference between the round-trip delay of the feeder link in the NTN and the first delay compensation value.

[0010] This implementation provides two possible ways to implement the first parameter, increasing the flexibility of the solution.

[0011] In one possible implementation, the first parameter is used to determine the difference between the round-trip delay of the feeder link in the NTN and the first delay compensation value. The first parameter can be the location coordinates of the compensation reference point. The difference is determined based on the round-trip delay between the compensation reference point and the second network device. The round-trip delay between the compensation reference point and the second network device is determined based on the location coordinates of the compensation reference point and the location coordinates of the second network device.

[0012] With this implementation, the terminal only needs to determine the difference based on the location coordinates of the compensation reference point and the location coordinates of the second network device, which provides a novel way of indicating the difference and is simple to implement on the terminal side.

[0013] In one possible implementation, to improve the flexibility of the solution, the first parameter can be either the difference or the position coordinates of the compensation reference point. Furthermore, the first network device can also send first indication information, which indicates that the first parameter is either the difference or the position coordinates of the compensation reference point.

[0014] Through this implementation method, the terminal device can determine whether the first parameter is the difference or the position coordinates of the compensation reference point based on the first indication information, and then use the corresponding algorithm to calculate the TA used to transmit the signal, thereby improving the flexibility of the solution while ensuring its reliability.

[0015] As an optional implementation, if the first parameter is the location coordinates of the compensation reference point, the first network device may also send second indication information, which indicates whether the difference is positive or negative; wherein, if the first delay compensation value is less than the round-trip delay of the power supply link or the compensation reference point is located on the power supply link, the difference is positive; or, if the first delay compensation value is greater than the round-trip delay of the power supply link or the compensation reference point is located on the serving link in the NTN, the difference is negative.

[0016] Through this implementation method, the terminal can determine the sign of the difference based on the second indication information, and then calculate TA based on the difference, thereby further ensuring the accuracy of TA.

[0017] In one possible implementation, the TA is: the sum of the round-trip time of the serving link in the NTN and the difference; or, the sum of the round-trip time of the serving link in the NTN, the difference, and the offset; wherein the offset is related to the time division duplex (TDD) mode or the frequency division duplex (FDD) mode.

[0018] This implementation method provides multiple possible ways to calculate TA, improving the flexibility and applicability of the solution.

[0019] In one possible implementation, the first network device may also send a second parameter, wherein the second parameter is used to indicate the common round-trip time of the service link of the coverage beam or cell of the second network device.

[0020] Through this implementation, a terminal without positioning function can obtain the common round-trip time of the service link of the coverage beam or cell of the second network device according to the second parameter, and then use the common round-trip time of the service link as the round-trip time of the service link between itself and the second network device, so as to ensure that the terminal without positioning function can also accurately calculate the TA.

[0021] In one possible implementation, the second parameter is used to indicate the common round-trip time of the serving link of the coverage beam or cell of the second network device, including: The second parameter is the common round-trip time of the service link of the coverage beam or cell of the second network device, or the second parameter is used to determine the common round-trip time of the service link of the coverage beam or cell of the second network device.

[0022] This implementation provides two possible ways to implement the second parameter, increasing the flexibility of the solution.

[0023] In one possible implementation, the second parameter is used to determine the common round-trip time of the serving link of the coverage beam or cell of the second network device, and the second parameter is the location coordinates of the serving link reference point; wherein, the common round-trip time of the serving link is determined based on the round-trip time between the serving link reference point and the second network device, and the round-trip time between the serving link reference point and the second network device is determined based on the location coordinates of the serving link reference point and the location coordinates of the second network device.

[0024] With this implementation, the terminal can determine the round-trip time between the service link reference point and the second network device based on the location coordinates of the service link reference point and the location coordinates of the second network device. This implementation provides a novel indication method for the common round-trip time of the service link of the coverage beam or cell of the second network device, and it is simple to implement on the terminal side.

[0025] In one possible implementation, the first network device may send a third indication message, which indicates that the second parameter is the common round-trip time of the service link or the location coordinates of the service link reference point.

[0026] Through this implementation method, the terminal device can determine whether the second parameter is the common round-trip time of the service link or the location coordinates of the service link reference point based on the third indication information, and then use the corresponding algorithm to calculate the TA used to send the signal, thereby improving the flexibility of the solution while ensuring its reliability.

[0027] In one possible implementation, the first network device may carry the first parameter in SIB1, OSI, or MIB; the first network device may also carry the first parameter in RRC information, RRC reconfiguration message, DCI, group DCI, MAC element, or TAC during the RRC connection phase; the first network device may also carry the first parameter in RRC reconfiguration message or BWP related signaling when the terminal performs cell / beam / BWP handover.

[0028] This implementation provides multiple ways for the first network device to send the first parameter, improving the flexibility of the solution.

[0029] Secondly, embodiments of this application provide a method for determining a TA (Transmission Time Acquisition), comprising: a second network device determining the location coordinates of a compensation reference point based on a second delay compensation value, wherein the second delay compensation value is a delay compensation value made by the second network device for a signal sent by a receiving terminal; wherein the second delay compensation value is used to determine the TA used by the terminal to send the signal, and the TA is equal to the round-trip time of the serving link in the NTN minus the second delay compensation value; and the second network device sending the location coordinates of the compensation reference point.

[0030] In this embodiment, since the position coordinates of the compensation reference point are determined by the second network device based on the second delay compensation value, and the second delay compensation value is the delay compensation value made by the second network device for the signal sent by the receiving terminal, when the terminal receives the position coordinates of the compensation reference point and determines the TA based on the position coordinates of the compensation reference point, it takes into account the delay compensation made by the second network device for the signal sent by the terminal. Therefore, it can improve the accuracy of the terminal in calculating the TA, and thus better improve the TA of the ISI problem.

[0031] In one possible implementation, the second network device may also send a second parameter, wherein the second parameter is used to indicate the common round-trip time of the serving link of the coverage beam or cell of the second network device.

[0032] Through this implementation, a terminal without positioning function can obtain the common round-trip time of the service link of the coverage beam or cell of the second network device according to the second parameter, and then use the common round-trip time of the service link as the round-trip time of the service link between itself and the second network device, so as to ensure that the terminal without positioning function can also accurately calculate the TA.

[0033] In one possible implementation, the second parameter is used to indicate the common round-trip time of the serving link of the second network device's coverage beam or cell, including: the second parameter being the common round-trip time of the serving link of the second network device's coverage beam or cell, or the second parameter being used to determine the common round-trip time of the serving link of the second network device's coverage beam or cell.

[0034] This implementation provides two possible ways to implement the second parameter, improving the flexibility of the solution. In one possible implementation, the second parameter is used to determine the common round-trip time (CRT) of the serving link of the coverage beam or cell of the second network device, and the second parameter is the location coordinates of the serving link reference point; wherein, the CRT of the serving link is determined based on the CRT between the serving link reference point and the second network device, and the CRT between the serving link reference point and the second network device is determined based on the location coordinates of the serving link reference point and the location coordinates of the second network device.

[0035] With this implementation, the terminal can determine the round-trip time between the service link reference point and the second network device based on the location coordinates of the service link reference point and the location coordinates of the second network device. This implementation provides a novel indication method for the common round-trip time of the service link of the coverage beam or cell of the second network device, and it is simple to implement on the terminal side.

[0036] In one possible implementation, the second network device may also send a third indication message, which indicates that the second parameter is the common round-trip time of the service link or the location coordinates of the service link reference point.

[0037] Through this implementation method, the terminal device can determine whether the second parameter is the common round-trip time of the service link or the location coordinates of the service link reference point based on the third indication information, and then use the corresponding algorithm to calculate the TA used to send the signal, thereby improving the flexibility of the solution while ensuring its reliability.

[0038] In one possible implementation, the second network device may transmit the location coordinates of the compensation reference point in SIB1, OSI, or MIB; the second network device may also transmit the location coordinates of the compensation reference point in RRC information, RRC reconfiguration messages, DCI, group DCI, MAC elements, or TAC during the RRC connection phase; the second network device may also transmit the location coordinates of the compensation reference point in RRC reconfiguration messages or BWP-related signaling when the terminal performs cell / beam / BWP handover.

[0039] This implementation provides multiple ways for the second network device to send the location coordinates of the compensation reference point, improving the flexibility of the solution.

[0040] Thirdly, embodiments of this application also provide a method for determining a TA, comprising: an ATG network device determining the location coordinates of an ATG reference point, wherein the location coordinates of the ATG reference point are used to determine the TA used by a terminal to send a signal to the ATG network device; and the ATG network device sending the location coordinates of the ATG reference point.

[0041] In this embodiment, the ATG network device sends the location coordinates of the ATG reference point to the terminal, enabling the terminal to calculate the TA used to transmit the signal based on the location coordinates of the ATG reference point, which can improve the ISI problem during ATG communication. Furthermore, since the ATG network device tells the terminal the location coordinates of the ATG reference point, not its own location coordinates, the location privacy of the ATG network device can be protected, and the security of ATG communication can be improved.

[0042] Fourthly, embodiments of this application provide a method for determining a transfer time (TA), comprising: a terminal receiving a first parameter, wherein the first parameter is used to indicate the difference between the round-trip time of a feeder link in a non-terrestrial network (NTN) and a first delay compensation value, the first delay compensation value being the delay compensation made by the first network device for a signal sent by the receiving terminal, and the difference being used to determine the TA used by the terminal to send the signal; the terminal determining the TA used to send the signal based on the first parameter.

[0043] In one possible implementation, the first parameter is used to indicate the difference between the round-trip delay of the feeder link in the NTN and the first delay compensation value, including: the first parameter being the difference between the round-trip delay of the feeder link in the NTN and the first delay compensation value; or, the first parameter being used to determine the difference between the round-trip delay of the feeder link in the NTN and the first delay compensation value.

[0044] In one possible implementation, the first parameter is used to determine the difference between the round-trip delay of the feeder link in the NTN and the first delay compensation value. The first parameter is the position coordinates of the compensation reference point. The difference is determined based on the round-trip delay between the compensation reference point and the second network device. The round-trip delay between the compensation reference point and the second network device is determined based on the position coordinates of the compensation reference point and the position coordinates of the second network device.

[0045] In one possible implementation, the method further includes: the terminal receiving first indication information, the first indication information being used to indicate that the first parameter is the difference or the location coordinates of the compensation reference point; the terminal determining the location coordinates of the first parameter as the difference or the compensation reference point based on the first indication information.

[0046] In one possible implementation, the method further includes: the terminal receiving second indication information, the second indication information indicating whether the difference is positive or negative; the terminal determining whether the difference is positive or negative based on the second indication information; wherein, if the difference is positive, the first delay compensation value is less than the round-trip time of the power supply link or the compensation reference point is located on the power supply link; or, if the difference is negative, the first delay compensation value is greater than the round-trip time of the power supply link or the compensation reference point is located on the serving link in the NTN.

[0047] In one possible implementation, the TA is: the sum of the round-trip time of the serving link in the NTN and the difference; or, the sum of the round-trip time of the serving link in the NTN, the difference, and the offset; wherein the offset is related to the time division duplex (TDD) mode or the frequency division duplex (FDD) mode.

[0048] In one possible implementation, the method further includes: the terminal receiving a second parameter, wherein the second parameter is used to indicate the common round-trip time of the serving link of the second network device coverage beam or cell.

[0049] In one possible implementation, the second parameter is used to indicate the common round-trip time of the serving link of the coverage beam or cell of the second network device, including: the second parameter being the common round-trip time of the serving link of the coverage beam or cell of the second network device; or, the second parameter being used to determine the common round-trip time of the serving link of the coverage beam or cell of the second network device.

[0050] In one possible implementation, the second parameter is used to determine the common round-trip time of the serving link of the coverage beam or cell of the second network device, and the second parameter is the location coordinates of the serving link reference point; wherein, the common round-trip time of the serving link is determined based on the round-trip time between the serving link reference point and the second network device, and the round-trip time between the serving link reference point and the second network device is determined based on the location coordinates of the serving link reference point and the location coordinates of the second network device.

[0051] In one possible implementation, the method further includes: the terminal receiving third indication information, the third indication information being used to indicate that the second parameter is the common round-trip time of the service link or the location coordinates of the service link reference point; the terminal determining, based on the third indication information, that the second parameter is the common round-trip time of the service link or the location coordinates of the service link reference point.

[0052] In one possible implementation, the first network device receives the first parameter, including: the terminal receiving System Information Block (SIB1), Other System Messages (OSI), or Master System Information Block (MIB) sent therein, wherein the first parameter is carried in the SIB1, the OSI, or the MIB; or, during the Radio Resource Control (RRC) connection phase, the terminal receives RRC information, RRC reconfiguration messages, Downlink Control Information (DCI), Group DCI, Medium Access Control (MAC) elements, or Time Advance Command (TAC), wherein the first parameter is carried in the RRC information, the RRC reconfiguration message, the DCI, the Group DCI, the MAC element, or the TAC; or, when the terminal performs cell / beam / partial bandwidth (BWP) handover, the first network device receives an RRC reconfiguration message or BWP-related signaling, wherein the first parameter is carried in the RRC reconfiguration message or the BWP-related signaling.

[0053] Fifthly, embodiments of this application provide a method for determining a Transmission Time (TA), comprising: a terminal receiving the location coordinates of a compensation reference point, wherein a second delay compensation value is a delay compensation value made by the second network device for a signal sent by the receiving terminal, the second delay compensation value is used to determine the TA used by the terminal to send the signal, the TA being equal to the round-trip time of the serving link in the NTN minus the second delay compensation value; the terminal determining the TA used to send the signal based on the location coordinates of the compensation reference point.

[0054] In one possible implementation, the method further includes: the terminal receiving a second parameter, wherein the second parameter is used to indicate the common round-trip time of the serving link of the second network device coverage beam or cell.

[0055] In one possible implementation, the second parameter is used to indicate the common round-trip time of the serving link of the coverage beam or cell of the second network device, including: the second parameter being the common round-trip time of the serving link of the coverage beam or cell of the second network device; or, the second parameter being used to determine the common round-trip time of the serving link of the coverage beam or cell of the second network device.

[0056] In one possible implementation, the second parameter is used to determine the common round-trip time of the serving link of the coverage beam or cell of the second network device, and the second parameter is the location coordinates of the serving link reference point; wherein, the common round-trip time of the serving link is determined based on the round-trip time between the serving link reference point and the second network device, and the round-trip time between the serving link reference point and the second network device is determined based on the location coordinates of the serving link reference point and the location coordinates of the second network device.

[0057] In one possible implementation, the method further includes: the terminal receiving third indication information, the third indication information being used to indicate that the second parameter is the common round-trip time of the service link or the location coordinates of the service link reference point; the terminal determining, based on the third indication information, that the second parameter is the common round-trip time of the service link or the location coordinates of the service link reference point.

[0058] In one possible implementation, the terminal sends the location coordinates of the compensation reference point, including: the terminal receiving System Information Block (SIB1), Other System Messages (OSI), or Master System Information Block (MIB), wherein the SIB1, OSI, or MIB carries the location coordinates of the compensation reference point; or, during the Radio Resource Control (RRC) connection phase, the terminal receives RRC information, RRC reconfiguration messages, Downlink Control Information (DCI), Group DCI, Medium Access Control (MAC) elements, or Timing Advance Command (TAC), wherein the RRC information, RRC reconfiguration messages, DCI, Group DCI, MAC elements, or TAC carries the location coordinates of the compensation reference point; or, during cell / beam / partial bandwidth (BWP) handover, the terminal receives RRC reconfiguration messages or BWP-related signaling, wherein the RRC reconfiguration messages or BWP-related signaling carry the location coordinates of the compensation reference point.

[0059] Sixthly, embodiments of this application provide a method for determining a Transmission Target (TA), comprising: a terminal receiving the position coordinates of an air-to-ground (ATG) reference point; and the terminal determining the TA used to transmit a signal based on the position coordinates of the ATG reference point.

[0060] In a seventh aspect, embodiments of this application provide a communication device. This device may be the first network device described in the first aspect above, or a component within the first network device (e.g., a chip, a chip system, or a circuit), or a device compatible with the first network device. The device may include modules that perform the methods / operations / steps / actions described in the first aspect and any possible implementation of the first aspect. These modules may be hardware circuits, software, or a combination of hardware circuits and software implementation.

[0061] For example, the device may include: a processing unit, configured to determine a first parameter based on a first delay compensation value, wherein the first delay compensation value is a delay compensation made by the first network device for a signal transmitted by a receiving terminal, and the first parameter is used to indicate the difference between the round-trip delay of the feeder link in the non-terrestrial network (NTN) and the first delay compensation value, the difference being used to determine the TA used by the terminal to transmit the signal; and a transmitting unit, configured to transmit the first parameter.

[0062] Eighthly, embodiments of this application provide a communication device, which may be the second network device described in the second aspect above, or a device within the second network device (e.g., a chip, a chip system, or a circuit), or a device compatible with the second network device. The device may include modules that perform the methods / operations / steps / actions described in the second aspect and any possible implementation of the second aspect. These modules may be hardware circuits, software, or a combination of hardware circuits and software implementation.

[0063] For example, the device may include: a processing unit, configured to determine the location coordinates of a compensation reference point based on a second delay compensation value, wherein the second delay compensation value is a delay compensation value made by the second network device for the signal sent by the receiving terminal; wherein the second delay compensation value is used to determine the TA used by the terminal to send the signal, and the TA is equal to the round-trip time of the serving link in the NTN minus the second delay compensation value; and a sending unit, configured to send the location coordinates of the compensation reference point.

[0064] Ninthly, embodiments of this application provide a communication device, which may be the ATG network device described in the second aspect above, or a device within the ATG network device (e.g., a chip, a chip system, or a circuit), or a device compatible with the ATG network device. The device may include modules that perform the methods / operations / steps / actions described in the third aspect and any possible implementation of the third aspect. These modules may be hardware circuits, software, or a combination of hardware circuits and software implementation.

[0065] For example, the device may include: a processing unit for determining the position coordinates of an ATG reference point, wherein the position coordinates of the ATG reference point are used to determine the TA used by the terminal to send a signal to the ATG network device; and a transmitting unit for transmitting the position coordinates of the ATG reference point.

[0066] In a tenth aspect, embodiments of this application provide a communication device. This device may be a terminal as described in the fourth aspect above, or a device within the terminal (e.g., a chip, a chip system, or a circuit), or a device compatible with the terminal. The device may include modules that perform the methods / operations / steps / actions described in the fourth aspect and any possible implementation of the fourth aspect. These modules may be hardware circuits, software, or a combination of hardware circuits and software implementation.

[0067] For example, the device may include: a receiving unit for receiving a first parameter, wherein the first parameter is used to indicate the difference between the round-trip time of the feeder link in the non-terrestrial network (NTN) and a first delay compensation value, the first delay compensation value being the delay compensation made by the first network device for the signal transmitted by the receiving terminal, and the difference being used to determine the TA used by the terminal to transmit the signal; and a processing unit for determining the TA used to transmit the signal based on the first parameter.

[0068] Eleventhly, embodiments of this application provide a communication device, which may be a terminal as described in the fifth aspect above, or a device within the terminal (e.g., a chip, a chip system, or a circuit), or a device that can be used in conjunction with the terminal. The device may include modules that perform the methods / operations / steps / actions described in the fifth aspect and any possible implementation of the fifth aspect. These modules may be hardware circuits, software, or a combination of hardware circuits and software implementation.

[0069] For example, the device may include: a receiving unit for receiving the position coordinates of a compensation reference point, wherein the second delay compensation value is a delay compensation value made by the second network device for the signal sent by the receiving terminal, the second delay compensation value is used to determine the TA used by the terminal to send the signal, and the TA is equal to the round-trip time of the serving link in the NTN minus the second delay compensation value; and a processing unit for determining the TA used to send the signal based on the position coordinates of the compensation reference point.

[0070] In a twelfth aspect, embodiments of this application provide a communication device. This device may be a terminal as described in the sixth aspect above, or a device within the terminal (e.g., a chip, a chip system, or a circuit), or a device compatible with the terminal. The device may include modules that perform the methods / operations / steps / actions described in the sixth aspect and any possible implementation of the sixth aspect. These modules may be hardware circuits, software, or a combination of hardware circuits and software.

[0071] For example, the device may include: a receiving unit for receiving the position coordinates of an air-to-ground ATG reference point; and a processing unit for determining the transmission TA (Transmission Target) used to transmit the signal based on the position coordinates of the ATG reference point.

[0072] In a thirteenth aspect, embodiments of this application provide a communication device, including a processor and a communication interface, the communication interface being used to communicate with other communication devices; the processor being used to run a set of programs to enable the methods described in any of the first, second, third, fourth, fifth, or sixth aspects and any possible implementations of the first, second, third, fourth, fifth, or sixth aspects to be implemented.

[0073] In a fourteenth aspect, embodiments of this application provide a computer-readable storage medium storing computer-readable instructions that, when executed on a communication device, cause the methods described in any of the first, second, third, fourth, fifth, or sixth aspects and any possible implementations of the first, second, third, fourth, fifth, or sixth aspects to be implemented.

[0074] In a fifteenth aspect, embodiments of this application provide a chip system including a processor and potentially a memory, for implementing the methods described in the first, second, third, fourth, fifth, or sixth aspects, and in any possible implementation of the first, second, third, fourth, fifth, or sixth aspects. The chip system may be composed of chips or may include chips and other discrete devices.

[0075] In a sixteenth aspect, embodiments of this application provide a computer program product including instructions that, when run on a computer, cause the computer to perform the methods described in any of the first, second, third, fourth, fifth, or sixth aspects described above, as well as any possible implementation of the first, second, third, fourth, fifth, or sixth aspects described above. Attached Figure Description

[0076] Figure 1 This is a schematic diagram of a possible terrestrial network communication system applicable to the embodiments of this application; Figure 2 A flowchart illustrating a method for determining TA provided in this application embodiment; Figure 3A and Figure 3B A schematic diagram for the compensation reference point; Figure 4 A diagram illustrating the common round-trip time of a service link; Figure 5 A flowchart illustrating another method for determining TA provided in this application embodiment; Figure 6A schematic diagram illustrating the compensation for round-trip delay between the reference point and the second network device; Figure 7 A flowchart illustrating another method for determining TA provided in this application embodiment; Figure 8 This is a schematic diagram of the network architecture of an ATG communication system applicable to the embodiments of this application; Figure 9 A flowchart illustrating another method for determining TA provided in this application embodiment; Figure 10 This is a schematic diagram of an NTN network architecture applicable to the embodiments of this application; Figure 11 A flowchart illustrating another method for determining TA provided in this application embodiment; Figures 12 to 16 This is a schematic diagram of the signaling structure sent from the network side to the terminal in an embodiment of this application; Figure 17 A schematic diagram of the compensation reference point on the power supply link; Figure 18 A diagram illustrating the compensation reference point on the service link; Figures 19 to 23 This is a schematic diagram of the signaling structure sent from the network side to the terminal in an embodiment of this application; Figure 24 From the perspective of TA rate of service link and / or the TA rate angle of the feeder link A schematic diagram; Figure 25 A schematic diagram of the structure of a communication device 2500 provided in an embodiment of this application; Figure 26 This is a schematic diagram of the structure of a communication device 2600 provided in an embodiment of this application; Figure 27 This is a schematic diagram of the structure of a communication device 2700 provided in an embodiment of this application; Figure 28 This is a schematic diagram of the structure of a communication device 2800 provided in an embodiment of this application; Figure 29 This is a schematic diagram of the structure of a communication device 2900 provided in an embodiment of this application; Figure 30 This is a schematic diagram of the structure of a communication device 3000 provided in an embodiment of this application. Detailed Implementation

[0077] To achieve global communication coverage for 5G networks, the 3rd Generation Partnership Project (3GPP) is researching the adaptation of the New Radio (NR) protocol to non-terrestrial networks (NTN). NTN communication includes satellite communication and air-to-ground (ATG) communication. Compared to terrestrial communication, NTN communication has different channel characteristics, such as high transmission latency and doppler frequency offset. For example, the round-trip latency of geostationary earthbit (GEO) satellite communication (regenerative mode) is 238–270 ms. The round-trip latency of low earth orbit (LEO) satellite communication (orbit altitude 1200 km, regenerative mode) is 8–20 ms. For ATG communication scenarios, the maximum round-trip latency can reach 1 ms.

[0078] Significant round-trip time (RTT) delays can cause inter-symbol interference (ISI) in uplink signals, impacting network-side decoding performance. During the initial random access phase, terminals send a preamble, and network devices return a random access response (RAR). To mitigate ISI, one possible solution is to require the preamble to have a long cyclic prefix (not less than the RTT) to ensure orthogonality between uplink signals from different terminals. However, the RTT in NTN communication scenarios is too large, making it difficult for the network device (CP) to meet this requirement. Another possible solution is for the network device to specify a timing advance (TA) value in the RAR when returning it to the terminal. This allows the terminal to use the TA for timing advance, thereby reducing the timing difference between the network device and each terminal. However, the range of TA adjustment values ​​indicated by network devices in RAR is currently 0~2ms. As the subcarrier spacing increases, the indication range of TA in RAR will decrease exponentially. For satellite communication scenarios, the maximum indication range of 2ms is insufficient to indicate the round-trip time delay in NTN communication scenarios. Expanding the TA indication range in RAR will consume more signaling overhead. For ATG communication scenarios, when the subcarrier spacing is greater than 30KHz, the indication range of TA in RAR will be less than 1ms, which is also insufficient to indicate the round-trip time delay in ATG communication scenarios.

[0079] To address this, existing technologies allow network devices to inform terminals of a common timing advance value before the terminal sends the random access preamble. The terminal then uses this common timing advance value to send the random access preamble. This reduces the timing difference between the network device and each terminal, reduces the timing range of uplink signals from each terminal reaching the network device, thereby reducing the requirement for the length of the cyclic prefix of the preamble and the requirement for the TA indication range in the RAR.

[0080] Currently, there are two main methods for network devices to inform terminals of common timing advance values: Option 1: The network device broadcasts a common timing advance value, and the terminal directly uses this common timing advance value to send the random access preamble. In transparent transmission mode (where the satellite lacks base station processing capability), the network device acts as a gateway station, and the common timing advance value can be calculated based on the round-trip delay from the reference point to the satellite and then to the gateway station. In regenerative mode (where the satellite has base station processing capability), the network device acts as the satellite, and the common timing advance value can be calculated based on the round-trip delay from the reference point to the satellite.

[0081] This solution is simple to implement; the terminal can directly use the common timing advance value after receiving it. However, in practical applications, network devices often perform latency compensation on the signals sent by the terminal. The terminal only needs to compensate for a portion of the common timing advance value. Terminals with positioning capabilities can calculate the round-trip time (RTD) between the terminal and the satellite, but they cannot obtain the uncompensated RTD between the satellite and the gateway station. Terminals with positioning capabilities cannot calculate the accurate timing advance (TA) based on the common timing advance value, and the terminal will still experience inter-satellite instability (ISI) after transmitting the signal.

[0082] Option 2: The network device broadcasts two common timing advance values: one for the service link and one for the feeder link. The terminal advances the timing of the service link based on the common timing advance value and advances the timing of the feeder link based on the common timing advance value.

[0083] The scheme clarifies the common timing advance for both the service link and the power supply link. However, if the network device performs delay compensation on the signal sent by the terminal, and the delay compensation covers the round-trip time of the entire power supply link and part of the service link, the terminal with positioning function will still be unable to calculate the accurate TA.

[0084] This application provides a method for determining the Terminal Ability (TA) to improve the accuracy of TA calculation by the terminal and alleviate the Inter-Insulation (ISI) problem. This method can be applied to fourth-generation (4G) communication systems, fifth-generation (5G) communication systems, device-to-device (D2D) communication, machine communication, or various future communication systems, such as sixth-generation (6G) communication systems.

[0085] The method provided in this application can be applied to non-terrestrial network (NTN) communication systems. Figure 1 This illustration shows the architecture of a possible terrestrial network communication system to which embodiments of this application apply. The communication system may consist of a terminal (or user terminal, user equipment), a first network device, and a second network device. The communication link between the first and second network devices is a feedback link (or feeder link); the communication link between the second network device and the terminal is a service link.

[0086] A terminal can be a wireless terminal device capable of receiving network device scheduling and instruction information. Examples include devices providing voice and / or data connectivity to users, handheld devices with wireless connectivity, or other processing devices connected to a wireless modem. Wireless terminal devices can communicate with one or more core networks or the Internet via a radio access network (RAN). Wireless terminal devices can be mobile terminal devices, such as mobile phones (or "cellular" phones), computers, and communication chips. For example, they can be portable, pocket-sized, handheld, computer-embedded, or vehicle-mounted mobile devices that can exchange voice and / or data with the radio access network. Specifically, a terminal can be a Personal Communication Service (PCS) telephone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a tablet computer, a computer with wireless transceiver capabilities, etc. Terminals can also include subscriber units, subscriber stations, mobile stations, mobile stations (MS), remote stations, access points (APs), remote terminals, access terminals, user terminals, user agents, subscriber stations (SSs), customer premises equipment (CPEs), terminals, and mobile terminals (MTs). Wireless terminal equipment can also be wearable devices and next-generation communication systems, such as terminal equipment in 5G networks, terminal equipment in future evolved public land mobile networks (PLMNs), and terminal equipment in NR communication systems.

[0087] The first network device can be a gateway station (also known as a ground station, earth station, or signal gateway), which can be used to connect the first network device to the core network.

[0088] The second network device can be a satellite (or satellite base station), a geostationary earthbit (GEO) satellite, a medium earth orbit (MEO) satellite or a low earth orbit (LEO) satellite, a high altitude platform station (HAPS), etc., without any restrictions.

[0089] In this embodiment of the application, the communication mode of the second network device may include two types: regenerative mode and transparent mode.

[0090] When the communication mode of the second network device is regeneration mode, the second network device can act as a wireless communication base station. For example, the second network device can use artificial earth satellites and high-altitude aircraft as wireless communication base stations, such as evolved NBs (eNBs) and 5G base stations (gNBs). The first network device can transmit the signaling between the second network device and the core network.

[0091] When the communication mode of the second network device is transparent transmission mode, the first network device acts as a base station for wireless communication, and the second network device can act as a relay for these base stations, and can transparently transmit signals between the first network device and the terminal.

[0092] It should be understood that Figure 1 Only one first network device and one second network device are shown. In actual use, an architecture with multiple first network devices and / or one second network device can be adopted as needed. Each second network device can provide services to one or more terminals, each second network device can correspond to one or more first network devices, and each first network device can correspond to one or more second network devices. This application does not specifically limit the specific implementation.

[0093] See Figure 2 This application provides a method for determining TA, which can be applied to... Figure 1 The communication system shown is in which the communication mode of the second network device is transparent transmission mode.

[0094] S201. The first network device determines the first parameter based on the first delay compensation value.

[0095] The first delay compensation value is the delay compensation performed by the first network device for the signal sent by the receiving terminal. In other words, the first delay compensation value is the delay compensation performed by the first network device when receiving the signal sent by the terminal to compensate for the timing difference caused by the round-trip delay of the service link and the round-trip delay of the power supply link. This delay compensation can be understood as the first network device delaying the receiving window backward when receiving the signal sent by the terminal, and the magnitude of this backward delay is the first delay compensation value. The sum of the round-trip delay of the service link and the round-trip delay of the power supply link should be greater than or equal to the first delay compensation value. The signal can be any signal sent by the terminal to the first network device, including but not limited to a random access preamble.

[0096] The first parameter is used to indicate the difference between the round-trip time (RTD) of the feeder link in the non-terrestrial network (NTN) and the first delay compensation value. One possible indication is that the first parameter is the difference between the RTD of the feeder link and the delay compensation value; another possible indication is that the first parameter is used to determine the difference between the RTD of the feeder link in the NTN and the delay compensation value. This difference can be used to determine the transfer action (TA) used by the terminal to transmit signals.

[0097] S202, The first network device sends the first parameter, and the terminal receives the first parameter.

[0098] Specifically, the first network device can first send the first parameter to the second network device, and then the second network device can forward the first parameter to the terminal.

[0099] S203. The terminal determines the TA used to transmit the signal based on the first parameter.

[0100] If the first parameter is the difference, the terminal can directly determine the TA used to send the signal based on the difference and the round-trip time of the service link, for example, by subtracting the difference from the round-trip time of the service link as the TA used to send the signal.

[0101] If the first parameter is the TA used to determine the signal transmitted by the terminal, the terminal needs to first determine the difference based on the first parameter, and then determine the TA used to transmit the signal based on the determined difference and the round-trip time of the service link.

[0102] As an optional implementation, when the first parameter is used to determine the difference between the round-trip time and the delay compensation value of the feeder link in the NTN, the first parameter can be the location coordinates of the compensation reference point. The difference is equal to the round-trip time between the compensation reference point and the second network device. The terminal device can determine the distance between the compensation reference point and the second network device based on the location coordinates of the compensation reference point and the second network device, and then determine the round-trip time between the compensation reference point and the second network device based on the distance.

[0103] As an optional implementation, to improve the flexibility of the solution, in specific implementation, the first parameter can be either the difference or the position coordinates of the compensation reference point. The first network device can send first indication information to the terminal to indicate that the first parameter is either the difference or the position coordinates of the compensation reference point.

[0104] In this way, the terminal device can determine whether the first parameter is the difference or the position coordinates of the compensation reference point based on the first indication information, and then use the corresponding algorithm to calculate the TA used to transmit the signal.

[0105] As an optional implementation, the first network device may also send a second indication message to the terminal, the second indication message being used to indicate whether the difference is positive or negative.

[0106] When the first parameter is a difference, the first network device sends a second indication message each time it sends the first parameter to indicate whether the first parameter is positive or negative. Specifically, the difference is positive when the first delay compensation value is less than the round-trip time of the power supply link; or, the difference is negative when the first delay compensation value is greater than the round-trip time of the power supply link.

[0107] When the first parameter is the coordinate position of the compensation reference point, the first network device can also send a second indication message to indicate the sign of the difference, or the sign can be represented by the sign of the coordinates. Specifically, when the first delay compensation value is less than the round-trip time of the feeder link, or when the compensation reference point is located on the feeder link, the difference is positive; or, when the first delay compensation value is greater than the round-trip time of the feeder link, or when the compensation reference point is located on the serving link in the NTN, the difference is negative. When the first delay compensation value is equal to the round-trip time of the feeder link, or when the compensation reference point is located on the second network device, the difference is 0. This situation can be categorized as either a positive or negative difference.

[0108] For example, see Figure 3A This is a schematic diagram showing the compensation reference point located on the feeder link. A represents the round-trip delay value of the serving link, D represents the first delay compensation value, and B represents the difference between the round-trip delay of the feeder link and the first delay compensation value. Figure 3A In the case shown, the difference is positive.

[0109] For example, see Figure 3B This diagram illustrates the compensation reference point when it is located on the serving link. A represents the round-trip time of the serving link, and the first delay compensation value D = D1 + D2, where D1 represents the round-trip time of the feeder link, and D2 represents the round-trip time between the compensation reference point and the second network device. B represents the difference between the round-trip time of the feeder link and the first delay compensation value. Figure 3A In the case shown, B = -D², and the difference is negative.

[0110] As an optional implementation, the first indication information and the second indication information are contained in the same indication information. For example, the first indication information and the second indication information are two different fields of one indication information.

[0111] As an optional implementation, the first network device may not indicate the positive or negative value of the difference. Instead, the terminal and the network device may pre-agree that the difference is equal to the round-trip delay of the power supply link minus the first delay compensation value or equal to the first delay compensation value minus the round-trip delay of the power supply link. The terminal may also agree to perform addition or subtraction calculations on the received difference after receiving it.

[0112] As an optional implementation, the calculation method for TA includes, but is not limited to, the following three: Method 1, TA equals the sum of the round-trip delay and the difference of the serving link; Method 2, the sum of the round-trip delay and the offset of the serving link in the NTN; Method 3, the sum of the round-trip delay, the difference, and the offset of the serving link in the NTN. In Methods 2 and 3, the offset is related to either Time Division Duplex (TDD) mode or Frequency Division Duplex (FDD) mode.

[0113] In existing technologies, the timing advance used by the terminal is T. Among them, (This text can also be written as NTA) is the TA adjustment value obtained by the terminal based on the parameters indicated by the first network device, such as the TA calculated by the terminal based on the first parameters sent by the first network device in this application. (NTAoffset can also be written as NTAoffset in this text) represents the timing interval from uplink to downlink transmission, sent to the terminal via SIB information. For FDD mode, NTAoffset=0; for TDD mode, NTAoffset=624. This time interval allows the base station sufficient time to switch between receiving uplink signals and transmitting downlink signals. Ts represents 1 / (15e3) 2048) seconds. μ is related to the subcarrier spacing, i.e., the subcarrier spacing is... kHz. Therefore, in this scheme, the TA calculated by the terminal based on the first parameter sent by the first network device can also be added to a fixed value (e.g., NTAoffset) before being used as the TA for the terminal to send signals.

[0114] In the embodiments of this application, the terminal may be a terminal with positioning function or a terminal without positioning function, and this application does not limit it.

[0115] For terminals with positioning capabilities, these terminals can calculate the distance between themselves and the second network device based on the positioning function, and then calculate the round-trip time between themselves and the second network device, and use it as the round-trip time of the service link.

[0116] For terminals without location functionality, the network device can issue a second parameter, which indicates the common round-trip time (CRT) of the serving link for the coverage beam or cell of the second network device. In one possible indication, the second parameter is the CRT of the serving link for the coverage beam or cell of the second network device; in another possible indication, the second parameter is used to determine the CRT of the serving link for the coverage beam or cell of the second network device. Furthermore, such terminals can use the CRT of the serving link as the CRT of the serving link between themselves and the second network device. For example, see... Figure 4 The round-trip delay between the second network device and the reference point closest to the second network device in the cell can be selected as the common round-trip delay of the service link.

[0117] As an optional implementation, when the second parameter is used to determine the common round-trip time (CRT) of the serving link of the coverage beam or cell of the second network device, the second parameter is the location coordinates of the serving link reference point. The CRT of the serving link is determined based on the CRT between the serving link reference point and the second network device, and the CRT between the serving link reference point and the second network device is determined based on the location coordinates of the serving link reference point and the location coordinates of the second network device.

[0118] To improve the flexibility of the solution, in specific implementation, the second parameter can be either the common round-trip time (CRT) of the serving link or the location coordinates of the serving link reference point. For example, in the non-staring mode of satellite communication, the coverage area of ​​the satellite beam / cell moves with the satellite, and the serving link reference point also moves with the satellite. In this case, the distance between the satellite and the serving link reference point remains constant, and the CRT remains constant. Sending the CRT of the serving link to the UE can avoid frequently changing the location coordinates of the sent serving link reference point, thus reducing system complexity. However, in the staring mode of satellite communication, the serving link reference point remains constant during the time the beam / cell continuously covers a certain area. Therefore, sending the location coordinates of the serving link reference point to the UE is more beneficial for reducing the complexity of system transmission signaling.

[0119] As an optional implementation, the first network device can send a third indication to the terminal, indicating whether the second parameter is the common round-trip time (CRT) of the serving link or the location coordinates of the serving link reference point. In this way, the terminal device can determine whether the second parameter is the CRT of the serving link or the location coordinates of the serving link reference point based on the third indication, and then use an algorithm corresponding to the determined CRT of the serving link or the location coordinates of the serving link reference point to calculate the transfer TA (TA) used to transmit the signal.

[0120] As an optional implementation, the first indication information and / or the second indication information are included in the same indication information as the third indication information. For example, the first indication information, the second indication information, and the third indication information are three different fields of one indication information. In the embodiments of this application, the first network device can send the above parameters (including the first parameter / second parameter) and / or indication information (including the first indication information / second indication information / third indication information) to the terminal in the following ways: Method 1: Carry the above parameters and indication information in the system information block (SIB), other system information (OSI) or the main system information block (MIB) and send them to the terminal via unicast, broadcast or multicast.

[0121] Method 2: During the radio resource control (RRC) connection phase, the first network device carries the above parameters and indication information in RRC information, RRC reconfiguration message, downlink control information (DCI), group DCI, media access control (MAC) element, or timing advance command (TAC) and sends it to the terminal, or sends it to the UE along with data transmission or in a separately allocated PDSCH bearer.

[0122] Method 3: When the first network device performs cell / beam / bandwidth part (BWP) handover at the terminal, it can send the above parameters and indication information in the RRC reconfiguration message or BWP-related signaling.

[0123] The above describes the technical solution when the second network device is in transparent transmission mode. Below, we describe the technical solution when the second network device is in regeneration mode.

[0124] In the above scheme, since the first parameter is the difference between the round-trip delay of the power supply link and the delay compensation value, or the first parameter can be used to determine the difference between the round-trip delay of the power supply link and the delay compensation value, the terminal determines the TA used to transmit the signal based on the first parameter, taking into account the delay compensation performed by the first network device on the signal transmitted by the terminal. Therefore, the terminal can calculate a more accurate TA, which can improve the ISI problem.

[0125] See Figure 5 This application provides another method for determining TA, which can be applied to... Figure 1 The communication system shown is in which the communication mode of the second network device is regeneration mode.

[0126] S501, The second network device determines the location coordinates of the compensation reference point based on the second delay compensation value; The second delay compensation value is the delay compensation made by the second network device for the signal sent by the receiving terminal. It can be equal to the round-trip delay between the compensation reference point and the second network device; or, in other words, the second delay compensation value is the delay compensation made by the second network device when receiving the signal sent by the terminal to compensate for the timing difference caused by the round-trip delay of the service link. This delay compensation can be understood as the second network device delaying the receiving window when receiving the signal sent by the terminal, and the magnitude of this delay is the second delay compensation value. The round-trip delay of the service link should be greater than or equal to the second delay compensation value. The signal can be any signal sent by the terminal to the second network device, including but not limited to random access preambles.

[0127] S502, The second network device sends the location coordinates of the compensation reference point, and the terminal receives the location coordinates of the compensation reference point.

[0128] S503. The terminal determines the TA used to transmit the signal based on the position coordinates of the compensation reference point.

[0129] Specifically, the terminal calculates the round-trip time between the compensation reference point and the second network device based on the location coordinates of the compensation reference point, thereby obtaining the second delay compensation value; then, it determines the TA used to transmit the signal based on the round-trip time of the service link and the second delay compensation value. For example, see... Figure 6 The location coordinates of the compensation reference point are located on the service link. The round-trip delay B between the compensation reference point and the second network device represents the delay compensation value made by the second network device for the signal sent by the receiving terminal. Therefore, the TA used by the terminal to send the signal can be equal to the round-trip delay of the service link minus the second delay compensation value, i.e., AB.

[0130] Similar to the transparent transmission mode described above, in the regeneration mode, the terminal can be either a terminal with positioning capabilities or a terminal without positioning capabilities; this application does not impose any limitations. For terminals with positioning capabilities, these terminals can calculate the distance between themselves and the second network device based on their positioning capabilities, and then calculate the round-trip time (RTT) between themselves and the second network device, using it as the RTT of the service link. For terminals without positioning capabilities, the second network device can issue a second parameter, where the second parameter is the common RTT of the service link of the second network device's coverage beam or cell, or the second parameter is used to determine the common RTT of the service link of the second network device's coverage beam or cell. These terminals can use the common RTT of the service link as the RTT of the service link between themselves and the second network device. The specific implementation method of the second parameter can refer to the specific implementation method of the second parameter in the transparent transmission mode described above, and will not be repeated here.

[0131] Similarly, in regeneration mode, the second network device can also send a third indication message to the terminal. The third indication message is used to indicate that the second parameter is the common round-trip time of the service link or the location coordinates of the service link reference point.

[0132] Similarly, in regeneration mode, the second network device can also send parameters or information using the three methods described in the transparent transmission mode. For example, the second network device can send the location coordinates of the compensation reference point to the terminal in SIB1, OSI, or MIB; or during the RRC connection phase, the second network device can send the location coordinates of the compensation reference point to the terminal in RRC information, RRC reconfiguration messages, DCI, group DCI, MAC elements, or TAC; or, when the terminal performs cell / beam / BWP handover, the second network device can send the location coordinates of the compensation reference point to the terminal in RRC reconfiguration messages or BWP-related signaling.

[0133] In an alternative implementation, the second network device can directly send the second delay compensation value to the terminal, so that the terminal can directly calculate the TA used to send the signal based on the second delay compensation value.

[0134] In the above scheme, the second network device sends the location coordinates of the compensation reference point, so that the terminal can calculate the round-trip time between the compensation reference point and the second network device based on the location coordinates of the compensation reference point, and thus obtain the second delay compensation value. In this way, when the terminal calculates the TA based on the location coordinates of the compensation reference point, it takes into account the delay compensation made by the network side for the signal sent by the terminal. Therefore, the terminal can calculate a more accurate TA, thereby improving the ISI problem.

[0135] In this embodiment, the terminal does not need to distinguish between regeneration mode and transparent transmission mode; in other words, the terminal treats the first network device and the second network device as a whole (network side). After receiving parameters from the network side (such as the location coordinates of the compensation reference point, the difference, the second delay compensation value, the first indication information, or the second indication information, etc.), the terminal directly determines the TA used to transmit the signal based on the received parameters. Figure 5 and Figure 2 The two schemes shown can be combined into one scheme for implementation.

[0136] For example, refer to Figure 7 This application provides another method for determining TA, which can be applied to... Figure 1 The communication system shown.

[0137] S701, The terminal receives the third parameter and the second indication information; For example, the third parameter can be the position coordinates of the compensation reference point (in regeneration mode or pass-through mode), it can be the difference (in pass-through mode), or it can be the second delay compensation value (in regeneration mode). The second indication information can be used to indicate the sign of the third parameter (the difference or the second delay compensation value), or to indicate the sign of the difference or the second delay compensation value determined based on the third parameter.

[0138] S702, The terminal determines the TA to be used for transmitting the signal based on the third parameter and the second indication information.

[0139] For example, if the third parameter is a difference value, the difference value is positively or negatively adjusted according to the second indication information, and then summed or subtracted with the round-trip time of the service link to determine the TA used for transmitting the signal; if the third parameter is a second delay compensation value, the second delay compensation value is positively or negatively adjusted according to the second indication information, and then summed or subtracted with the round-trip time of the service link to determine the TA used for transmitting the signal; if the third parameter is the position coordinates of the compensation reference point, the difference value or the second delay compensation value is determined according to the position coordinates of the compensation reference point, and then the difference value or the second delay compensation value is positively or negatively adjusted according to the second indication information, and finally summed or subtracted with the round-trip time of the service link to determine the TA used for transmitting the signal.

[0140] It should be understood that the above Figure 2 or Figure 5 Various possible implementations in the illustrated method embodiments can be referenced in this method embodiment. For example, for terminals without positioning capabilities, the location coordinates of the service link reference point can be received from the network side, and then the round-trip time between the service link reference point and the second network device can be determined based on the location coordinates of the service link reference point and the location coordinates of the second network device, i.e., the common round-trip time of the service link. Such terminals can use the common round-trip time of the service link as the round-trip time of the service link between themselves and the second network device. For terminals with positioning capabilities, the distance between themselves and the second network device can be calculated based on the positioning capability, and then the round-trip time between themselves and the second network device can be calculated and used as the round-trip time of the service link. For specific methods, please refer to the relevant sections above, which will not be repeated here.

[0141] In this embodiment, the terminal does not need to distinguish (or know) whether the second network device is in transparent transmission mode or regeneration mode, and the terminal can still calculate the accurate TA. That is, after receiving the parameters, the terminal directly calculates the parameters to determine the TA used to send the signal, which reduces the difficulty of implementation on the terminal side.

[0142] In existing technologies, the scheme of broadcasting common timing advance values ​​by network devices is generally used in satellite communication systems. For ATG communication systems, since the coverage area of ​​ATG network devices (the height is generally 6-12km and the diameter is about 100-300km) is large, the round-trip delay between terminals and ATG network devices at different locations within the coverage area of ​​ATG network devices is large. Therefore, the scheme of broadcasting common timing advance values ​​is not suitable for ATG communication.

[0143] Therefore, embodiments of this application also provide a method for determining the TA, so as to enable a terminal in an ATG network to determine the TA used to transmit signals.

[0144] This solution can be applied to ATG communication systems. For example, Figure 8 This is a schematic diagram of a network architecture for an ATG communication system applicable to embodiments of this application. The ATG communication system includes air-to-ground ATG network equipment and terminals. The ATG network equipment includes ground base stations, and the terminals include high-altitude mobile terminals, such as those found in high-altitude aircraft. See also... Figure 9 The method includes: S901, ATG network devices determine the location coordinates of the ATG reference point.

[0145] The location coordinates of the ATG reference point can be understood as the virtual location coordinates of the ATG network device. The distance between the location coordinates of the ATG reference point and the location coordinates of the ATG network device meets a preset range, for example, it is less than a preset distance value.

[0146] S902, ATG network devices send the location coordinates of ATG reference points to the terminal.

[0147] The specific implementation method of ATG network devices issuing ATG reference points can be referred to the specific implementation method of the first or second network device issuing the location coordinates of compensation reference points or service link reference points in the above text, and will not be repeated here.

[0148] S903: The terminal determines the TA used to send signals to the ATG network device based on the location coordinates of the ATG reference point.

[0149] Specifically, the terminal calculates the round-trip time between itself and the ATG reference point based on its own location coordinates and the location coordinates of the ATG reference point, and determines the round-trip time as the TA used to send signals to the ATG network device, or adds an offset to the round-trip time and uses it as the TA used to send signals to the ATG network device.

[0150] In the above scheme, the ATG network device sends the location coordinates of the ATG reference point to the terminal, so that the terminal can calculate the TA used to send the signal based on the location coordinates of the ATG reference point. Furthermore, since the ATG network device tells the terminal the location coordinates of the ATG reference point, not its own location coordinates, the location privacy of the ATG network device can be protected, and the security of ATG communication can be improved.

[0151] In practice, both the ATG system and the satellite system belong to the NTN communication system. Therefore, the technical solutions in the ATG communication scenario and the technical solutions in the satellite communication scenario can be combined and implemented.

[0152] See Figure 10 This is a schematic diagram of an NTN network architecture applicable to the embodiments of this application. The communication system includes equipment in the satellite communication system (such as satellites, gateway stations, terminals, etc.) and equipment in the ATG communication system (such as base stations, terminals, etc.).

[0153] See Figure 11 This application provides another method for determining TA, which can be applied to... Figure 10 The communication system shown.

[0154] S1101, The network side sends at least one parameter among the following to the terminal: the location coordinates of the service link reference point (hereinafter referred to as the service link reference point location coordinates), the location coordinates of the compensation reference point (compensation reference point location coordinates), and the location coordinates of the ATG reference point (ATG reference point location coordinates), and the terminal receives the at least one parameter.

[0155] The network side can be any one or more network devices in the NTN system, such as satellites, gateway stations, or base stations. The terminal can be a ground user terminal (such as a mobile phone, computer, vehicle-mounted equipment, etc.) or a high-altitude user terminal (such as a high-altitude aircraft).

[0156] Service link reference point: This is for terminals without positioning capabilities. It is used by these terminals to calculate the round-trip time between the satellite and the service link reference point to obtain the common round-trip time of the service link (or the timing advance adjustment value of the service link), which can be used as the round-trip time of the service link. The service link reference point can be selected at a point within the coverage area of ​​the beam / cell. It can be selected at a point on the horizontal plane or at a fixed altitude above the horizontal plane, depending on the requirements of the network deployment.

[0157] Compensation reference point: 1) When the compensation reference point is on the feeder link, the round-trip delay between the gateway station and the compensation reference point is the delay compensation value made by the network side for the uplink signal (i.e., the first delay compensation value mentioned above); 2) When the compensation reference point is on the service link, for transparent transmission mode, the round-trip delay from the gateway station to the satellite to the compensation reference point is the delay compensation value made by the network side for the uplink signal (i.e., the first delay compensation value mentioned above); for regeneration mode, the round-trip delay from the satellite to the compensation reference point is the delay compensation value made by the network side for the uplink signal (i.e., the second delay compensation value mentioned above). The compensation reference point can be selected on the service link or the feeder link, and can be determined according to the delay compensation value of the signal sent by the terminal by the network side.

[0158] ATG Reference Point: The terminal obtains the TA used by the terminal based on its location and the round-trip time delay of the ATG reference point. The ATG reference point can be selected at any location in the ATG beam or cell coverage area (including the coordinates of the base station location) as needed by the system.

[0159] S1102. The terminal determines the TA to be used for transmitting the signal based on the at least one parameter.

[0160] In one possible implementation, the terminal (e.g., an aircraft, a ground mobile terminal) can perform the following calculations based on the received reference point coordinates: 1) Calculate the round-trip time delay (or timing advance adjustment) of the service link based on the satellite position (obtained from ephemeris or satellite coordinates) and the service link reference point: A, where A is a positive number. For ease of description, A can be referred to as the common timing advance value of the service link in the following text.

[0161] 2) Calculate the round-trip time delay between the satellite and the compensation reference point based on the satellite position and the compensation reference point: B. If the compensation reference point is on the power supply link, then B is a positive value; if the compensation reference point is on the service link, then B is a negative value. The sign of this B value can be indicated to the UE through the second indication information above.

[0162] If the satellite is in transparent transmission mode, then B is the difference between the round-trip delay of the feeder link and the delay compensation value made by the satellite for the signal transmitted to the terminal; if the satellite is in regenerative mode, then B is the negative value of the delay compensation value made by the satellite for the signal transmitted to the terminal.

[0163] For ease of description, B can be referred to as the public compensation timing advance value in the following text.

[0164] 3) Calculate the round-trip time delay between the terminal and the ATG reference point based on the terminal location and the ATG reference point: C, where C is a positive number.

[0165] In another possible implementation, the network side can also directly send A, B, or C, meaning that at least one parameter can include A, B, or C. For example, the network side sends B without sending the coordinates of the compensation reference point.

[0166] Furthermore, the terminal can select different parameters from A, B, and C to calculate the TA used when transmitting signals (such as random access preambles) based on different communication scenarios (such as ATG communication, satellite communication, etc.). For example, when the terminal is in a satellite communication scenario: 1) If the terminal has a positioning function, the terminal can calculate the timing advance TA_cal of the service link based on the ephemeris, and then calculate TA based on TA_cal and B, such as: TA = TA_cal + B.

[0167] 2) If the terminal does not have a positioning function, the terminal can calculate TA based on A and B, such as: TA = A+B.

[0168] For example, when the terminal is in an ATG communication scenario: The terminal can calculate TA based on C, such as: TA = C.

[0169] The following will provide a detailed description through several specific examples. Figure 11 The specific implementation of the method shown.

[0170] Example 1

[0171] The base station can send the coordinates of the reference point to the terminal via broadcast, multicast, or unicast. See also... Figure 12 This is a schematic diagram of a possible reference point coordinate signaling provided in an embodiment of this application.

[0172] The reference point coordinates can be in the same coordinate system as the satellite or relative coordinates. For example, the service link reference point coordinates and compensation reference point coordinates can be coordinates relative to the satellite coordinate position, that is, with the satellite as the coordinate origin.

[0173] The compensation reference point coordinate parameters can include a positive / negative indicator bit to indicate whether the calculated round-trip delay between the second network device and the compensation reference point is positive or negative. For example, a positive / negative indicator bit of 0 indicates a negative value, and 1 indicates a positive value. If the round-trip delay is calculated to be x seconds using the compensation reference point coordinates and satellite coordinates, and the positive / negative indicator bit is 0, then the calculated B in the scheme is -x.

[0174] In the case of satellite communication, the network side can further perform the following operations: 1) You can set the ATG reference point coordinates to zero, or not send the ATG reference point coordinates.

[0175] 2) Whether to send the compensation reference point coordinates can be selected based on whether the network side compensates for the signal sent by the terminal, or the coordinates can be set to zero. For example, if the network side does not perform delay compensation, the compensation reference point coordinates can be either not sent or sent with the coordinates set to zero.

[0176] 3) Depending on whether the satellite communication is in transparent or regenerative mode, the sending of compensation reference point coordinates can be selected. For example, when the satellite is in transparent mode, even if the network does not perform delay compensation on the signal sent by the terminal, it still needs to send compensation reference point coordinates to the terminal to indicate the round-trip time delay value of the feeder link. In this case, the compensation reference point coordinates can be the location coordinates of the gateway station. The terminal can calculate the round-trip time delay value of the feeder link based on the compensation reference point coordinates and the satellite coordinates. At the same time, by combining the round-trip time delay value of the service link, the complete round-trip time delay of the communication link can be obtained, which is used as the timing advance adjustment value for the terminal's signal transmission. When the satellite is operating in regenerative mode, if the network does not perform delay compensation on the signal sent by the terminal, then the sending of compensation reference point coordinates is not necessary.

[0177] In the case of ATG communication, the network side can further perform the following operations: 1) The service link reference point coordinates and compensation reference point coordinates can be set to zero, or the service link reference point coordinates and compensation reference point coordinates can be not sent.

[0178] 2) In ATG communication scenarios, if the network side performs latency compensation on the signals sent by the terminal, it needs to send a compensation reference point to inform the terminal of the latency compensation value applied by the network side to the signals sent by the terminal. In this case, the service link reference point coordinates are set to zero, or the service link reference point coordinates are not sent.

[0179] Of course, satellite communication scenarios and ATG communication scenarios can coexist. If both satellite communication scenarios and ATG communication scenarios exist, the network side and the terminal can simultaneously execute the operations performed by the network side and the terminal in the ATG communication scenarios described above. For specific implementation methods, please refer to the satellite communication scenario and ATG communication scenario descriptions respectively, which will not be repeated here.

[0180] In one possible design, the smallest coordinate granularity or unit for the serving link reference point coordinates, compensation reference point coordinates, and ATG reference point coordinates is based on meters (m). In another possible design, combinations of several length units can be used, such as a combination of km and m, to save signaling overhead. If a single length unit is used to represent the three-dimensional coordinates of the serving link reference point as (10300m, 9600m, 10070m), then representing the three numbers 10030, 9600, and 10070 requires 42 bits. Using a combination of km and m, it can be represented as (10km+300m, 9km+600m, 10km+70m), requiring the transmission of the numbers 10, 300, 9, 600, 10, and 70, occupying 39 bits. Using combinations of multiple length units can save signaling overhead.

[0181] To further reduce signaling overhead, one possible design is to transmit reference point coordinates using the satellite orbital altitude H as the reference length. For example, if the network sends reference point coordinates (a, b, c) to the terminal, the terminal can calculate the reference point coordinates to be used based on (a+H, b+H, c+H). Alternatively, the satellite coordinates can be used as the reference point for transmission. For example, if the satellite coordinates are (x, y, z), and the network sends reference point coordinates (a, b, c) to the terminal, the terminal can calculate the reference point coordinates to be used based on (x+a, y+b, z+c).

[0182] The reference point coordinate signaling format provided in this embodiment is compatible with both satellite communication and ATG communication scenarios, and supports both terminals with and without positioning functions in determining the reference point coordinate (TA), thus saving signaling bits.

[0183] Example 2

[0184] See Figure 13 This is a schematic diagram of another possible reference point coordinate signaling provided in an embodiment of this application. It differs from Embodiment 1 in that: Figure 13 The signaling shown includes an added satellite communication / ATG communication scenario indication bit, used to indicate which scenario the reference point coordinates sent by the network side are applicable to. For example, it indicates to the terminal that the transmitted signaling is the service link reference point coordinates, the compensation reference point coordinates, the ATG reference point coordinates, or some other combination.

[0185] In this embodiment, satellite communication and ATG communication can reuse the same coordinate signaling bits, reducing signaling overhead.

[0186] Example 3

[0187] Unlike Embodiment 1 or Embodiment 2 above, this embodiment replaces one or more reference point coordinates with a common timing advance value, that is, it uses both the common timing advance and the reference point coordinates. (For ease of description, the service link common timing advance value, the common compensation timing advance value, and the ATG common timing advance value can be collectively referred to as the common timing advance value, and the service link reference point, compensation reference point coordinates, and coordinate ATG reference point coordinates can be referred to as the reference point coordinates.)

[0188] For example, see Figure 14A , Figure 14B The network side uses the common timing advance value of the service link (i.e., the round-trip delay of the service link) instead of the coordinates of the service link reference point.

[0189] For example, see Figure 14A , 14C The coordinates of the compensation reference point are replaced by the common compensation timing advance value (i.e., the round-trip time delay between the compensation reference point and the satellite).

[0190] For example, see Figure 14D The ATG reference point coordinates are replaced with the ATG common timing advance value (i.e., the common round-trip time in the ATG service area).

[0191] The relationship between the common compensation timing advance value and the compensation reference point can be: the common compensation timing advance value is equal to the round-trip time delay between the satellite position and the compensation reference point position. 1) When the compensation reference point is on the feeder link, the common compensation timing advance value is used as a positive value, corresponding to... Figure 14D The positive and negative indicator bits are positive. 2) When the compensation reference point is on the service link, the common compensation timing advance value is negativeed before use, corresponding to... Figure 14D The positive / negative indicator bit is negative.

[0192] It should be noted that if the compensation reference point is always on the power supply link or the compensation for the signal delay sent by the terminal from the network side is no greater than the round-trip delay of the power supply link, then the round-trip delay or common compensation timing advance value calculated using the compensation reference point will always be a positive value. Therefore, the positive / negative indicator bit of the compensation reference point or common compensation timing advance value can be omitted, i.e., it defaults to a positive value. Alternatively, if the compensation reference point is always on the service link or the compensation for the signal delay sent by the terminal from the network side is no less than the round-trip delay of the power supply link, then the network side and the terminal agree that the round-trip delay or common compensation timing advance value calculated using the compensation reference point used by the terminal will always be a negative value. Therefore, the positive / negative indicator bit of the compensation reference point or common compensation timing advance value can also be omitted, i.e., it defaults to a negative value. The method of this embodiment applies to all embodiments herein.

[0193] In one alternative implementation, for scenarios where ATG reference points do not need to be transmitted, the common timing advance value / service link reference point coordinates and the common compensation timing advance value / compensation reference point coordinates can be used in combination.

[0194] See Figure 14E In non-staring communication, the combined use of the serving link common timing advance value and the common compensation timing advance value / compensation reference point coordinates is more conducive to reducing the complexity of system transmission signaling. In staring mode, the combined use of the serving link reference point coordinates and the common compensation timing advance value / compensation reference point coordinates is more conducive to reducing the complexity of system transmission signaling. This is because in staring mode, the serving link reference point remains unchanged during the time period when the beam / cell continuously covers a certain area, and the serving link reference point coordinates sent from the network side to the terminal do not need to be changed. The choice between using the common compensation timing advance value or the compensation reference point coordinates depends on whether the network side compensates for the signal delay sent by the terminal and whether the compensation value is fixed, which will not be elaborated here.

[0195] In summary, the reasonable combination of common timing advance value / service link reference point coordinates and common compensation timing advance value / compensation reference point coordinates can reduce the complexity of system signaling.

[0196] In one optional implementation, for satellite communication scenarios, the ATG reference point coordinates / ATG common timing advance value can be set to zero or not transmitted. For ATG communication scenarios, the service link common timing advance value / service link reference point coordinates and / or common compensation timing advance value / compensation reference point coordinates can be set to zero or not transmitted.

[0197] In one alternative implementation, if the network side does not have the coordinates of the transmission compensation reference point / service link reference point, it can be assumed to fall back to the default coordinates, for example, to fall back to the satellite coordinates, i.e., the common compensation timing advance value is 0.

[0198] In one alternative implementation, the common timing advance value and the common compensation timing advance value of the service link can be represented by a combination of different time units. For example, assuming the common timing advance value of the service link is 20.77 ms, 12 bits are required to represent it when only the ms unit is used. If it is jointly represented using the units of frame length (10 ms) and subframe length (1 ms): 2 Frame length +0.77 Subframe length. The network side only needs 9 bits to represent it, which saves signaling overhead. Similarly, it can be jointly represented using the LTE basic time unit Ts and multiples of Ts, for example: a Ts+b Ts 10^3, you only need to send a and b to the terminal.

[0199] In this embodiment, the terminal uses a common timing advance value instead of the transmitted reference point coordinates. In certain scenarios, using a common timing advance value to replace the reference point coordinates can reduce the complexity of signaling transmission and updates. For example, in the non-staring mode of satellite communication, the coverage area of ​​the beam / cell moves with the satellite, and the serving link reference point also moves with the satellite. In this case, the distance between the satellite and the reference point remains constant, and the round-trip delay remains constant. In this situation, sending the serving link reference point coordinates to the terminal instead of the serving link common timing advance value avoids frequently changing the transmitted serving link reference point coordinates, reducing system complexity.

[0200] Example 4

[0201] This embodiment is based on embodiment 3, but adds a satellite communication / ATG communication scenario indicator bit to indicate the scenario to which the reference point coordinates sent by the network side are applicable.

[0202] For example, see Figure 15A , Figure 15B The signaling transmitted to the terminal by the communication scenario indicator bit is the coordinates of the service link reference point, the common compensation timing advance value, or the coordinates of the ATG reference point, or other combinations thereof.

[0203] In this embodiment, satellite communication and ATG communication can reuse the same signaling bits, which can reduce the signaling overhead of the entire NTN system.

[0204] Example 5

[0205] See Figure 15C This embodiment, based on Embodiment 3, adds an indicator bit to the service link common timing advance value / reference point coordinate signaling to indicate whether the signaling represents the service link common timing advance value or the service link reference point coordinate value. In this way, the system can decide whether to inform the terminal in the form of common timing advance value or reference point coordinates based on whether the satellite is in staring mode and whether the network side performs delay compensation on the signal sent by the terminal, thus improving the system's flexibility.

[0206] Similarly, an indicator bit can be added to the common compensation timing advance value / compensation reference point coordinate signaling to indicate whether the signaling represents the common compensation timing advance value or the compensation reference point coordinate value. This provides flexibility for configuring signaling on the network side.

[0207] See Figure 15DFor scenarios where ATG reference points do not need to be transmitted, the common timing advance value / service link reference point coordinates and the common compensation timing advance value / compensation reference point coordinates can be sent separately.

[0208] Example 6

[0209] Based on Example 5, this embodiment adds a satellite communication / ATG communication scenario indicator bit to indicate the scenario to which the reference point coordinates sent by the network side are applicable.

[0210] For example, see Figure 16 The signaling transmitted to the terminal by the communication scenario indicator bit can be the common timing advance value / coordinates of the service link reference point, the common compensation timing advance value / coordinates of the compensation reference point, or the coordinates of the ATG reference point, or other combinations thereof.

[0211] This embodiment allows satellite communication and ATG communication scenarios to reuse the same signaling bits, reducing signaling overhead.

[0212] Example 7

[0213] This embodiment provides that the network side indicates to the terminal the sign of the common compensation timing advance value / compensation reference point coordinates through implicit indication (i.e., to indicate whether the value is positive or negative when using this part of the value).

[0214] In one optional implementation, the compensation reference point coordinates are represented using relative coordinates. For example, the compensation reference point coordinates are represented as coordinates relative to the satellite's position, i.e., with the satellite as the origin of the coordinate system. If the compensation reference point coordinates are above the satellite, they are represented as positive values; if they are below the satellite, they are represented as negative values.

[0215] In another optional implementation, the sign of a certain dimension in the three-dimensional coordinates of the compensation reference point indicates whether the round-trip time calculated using the compensation reference point is positive or negative. For example, if the network sends the coordinates of the compensation reference point to the terminal as (-501km, 580km, 520km), and the network and the terminal agree that the sign of the first dimension value of the coordinate point indicates whether the calculated round-trip time is positive or negative, then the round-trip time calculated by the terminal based on the reference point coordinates (-501km, 580km, 520km) is negative.

[0216] Through this embodiment, the network side does not need to add additional signaling to indicate the positive or negative value of the common compensation timing advance value / compensation reference point coordinates, which can save signaling overhead.

[0217] Example 8

[0218] For terminals with positioning capabilities in the NTN system, the signaling sent from the network side to the terminal may not include the service link common compensation timing advance value / service link reference point coordinates, in order to save unnecessary signaling overhead.

[0219] For example, the signaling sent from the network side to the terminal only needs to include the common compensation timing advance value / compensation reference point coordinate parameters (including positive and negative indicator bits). Alternatively, the signaling sent from the network side to the terminal only needs to include the common compensation timing advance value / compensation reference point coordinate parameters (including positive and negative indicator bits) and the ATG reference point coordinates.

[0220] Because a terminal with positioning capabilities can calculate the round-trip time (RTT) of the service link based on its own location and the satellite's location (which the terminal can obtain from ephemeris information), it does not need the service link common timing advance value / service link reference point coordinates indicating the service link common RTT value. However, a terminal with positioning capabilities or a satellite cannot obtain the RTT of the feeder link based on ephemeris information. If the network side performs propagation delay compensation on the signal transmitted by the terminal, the terminal will also not be able to obtain the network side's delay compensation value. Therefore, a terminal with positioning capabilities cannot obtain complete propagation delay information, such as the feeder link propagation delay and the network side's propagation delay compensation value, solely based on its own location information and the satellite's location information.

[0221] like Figure 17As shown, if the network side's compensation value for the propagation delay of the signal sent to the terminal is less than the round-trip delay of the feeder link or the compensation reference point is on the feeder link, then a common compensation timing advance value can be used to represent the remaining propagation delay value in the feeder link after subtracting the network side's compensation for the delay. For example, if the round-trip delay of the feeder link is 'a' (i.e., the round-trip delay of the signal propagation between the satellite and the gateway station is 'a'), and the network side's compensation value for the propagation delay of the feeder link is 'b' (i.e., the round-trip delay between the gateway station and the compensation reference point is 'b'), then the common compensation timing advance value sent by the network side to the terminal is equal to 'ab' (i.e., the round-trip delay between the satellite and the compensation reference point is 'ab'). Optionally, the network side can send a common compensation timing advance value of (ab) / 2 to the terminal (which can save signaling overhead), which is the remaining propagation delay value after subtracting the network side's compensation for the one-way propagation delay of the feeder link. When the terminal receives the common compensation timing advance value of (ab) / 2, it multiplies it by 2 before use. At this point, the positive / negative indicator bit of the common compensation timing advance value indicates a positive sign, meaning that the subsequent operation is an additive one. Then, the terminal adds the common compensation timing advance value (which equals the value of ab) to the service link round-trip time delay value calculated by the terminal to obtain the timing advance adjustment (TA) for the signal transmitted by the terminal. Similarly, the network side can send the compensation reference point coordinates, with the positive / negative indicator bit indicating a positive sign. The terminal calculates the round-trip time delay between the satellite position and the reference point position, and then, based on the positive sign indicated by the positive / negative indicator bit, adds the calculated service link round-trip time delay value to the common compensation timing advance value to obtain the TA usable by the terminal.

[0222] like Figure 18As shown, when the network side's compensation value for the propagation delay of the signal sent by the terminal is greater than the round-trip delay of the feeder link or the compensation reference point is on the serving link, i.e., the network side compensates for the propagation round-trip delay of the feeder link and part of the propagation round-trip delay of the serving link (the round-trip delay from the gateway station to the satellite to the compensation reference point), then a common compensation timing advance value can be used to represent the network side's compensation for part of the propagation round-trip delay of the serving link (i.e., the signal propagation round-trip delay between the satellite and the compensation reference point). For example, suppose the round-trip delay between the satellite and the compensation reference point is d, i.e., the common compensation timing advance value is d. Or, to save signaling overhead, let the common compensation timing advance value be d / 2. After receiving d / 2, the terminal multiplies it by 2 before proceeding with subsequent operations. In this case, the positive / negative indicator bit of the common compensation timing advance value indicates a negative sign, i.e., the subsequent operation is a subtraction operation. Then, the terminal subtracts the calculated serving link round-trip delay value from the common compensation timing advance value (i.e., the value equal to d) to obtain the timing advance adjustment TA for the signal sent by the terminal. Similarly, the network side can send the coordinates of the compensation reference point, and the positive / negative indicator bit indicates a negative sign. The terminal calculates the round-trip time delay between the satellite position and the reference point position. Then, based on the negative sign indicated by the positive and negative indicator bits, it subtracts the calculated service link round-trip time delay value from the common compensation timing advance value to obtain the TA that the terminal can use.

[0223] Example 9

[0224] As described in Examples 2, 4, and 6, when the network side indicates through an indicator bit that the information contained in the signaling is the coordinates of the service link reference point, the common timing advance value of the service link, the coordinates of the compensation reference point, the common compensation timing advance value, or the coordinates of the ATG reference point, the network side can inform the terminal of the reference point coordinates and the composition of the timing advance signaling by looking up a table.

[0225] As an example, Table 1 shows the reference point coordinates and timing advance signaling components corresponding to different index numbers. The network side can send index numbers to the terminal, which can then use these index numbers to look up the reference point coordinates and the composition of the timing advance signaling, and decode the signaling to obtain the corresponding data. For example, when the terminal receives index number 2, it means that the signaling received by the terminal includes the serving link common timing advance value, the compensation reference point coordinate value, and the ATG reference point coordinate value. For example, when the terminal receives index number 14, it means that the signaling received by the terminal includes the serving link common timing advance value and the compensation reference point coordinates.

[0226] Table 1. Reference point coordinates and timing advance signaling.

[0227] As an example, referring to Table 2, for cases where the terminal does not require ATG reference point coordinates, the table can be further reduced to save signaling overhead for transmitting index numbers. For example, when the terminal receives index number 3, it indicates that the signaling received by the terminal includes the service link reference point coordinates and the common compensation timing advance value.

[0228] Table 2 Reference point coordinates and timing advance signaling composition

[0229] It's important to note that if the compensation reference point is always on the power supply link, or if the network-side compensation for the signal delay transmitted to the terminal is no greater than the round-trip time of the power supply link, then the round-trip time or common compensation timing advance value calculated using the compensation reference point will always be positive. Therefore, the positive / negative indicator bits for the compensation reference point or common compensation timing advance value can be omitted, meaning it defaults to a positive value. Alternatively, if the compensation reference point is always on the service link, or if the network-side compensation for the signal delay transmitted to the terminal is no less than the round-trip time of the power supply link, then the network and the terminal agree that the round-trip time or common compensation timing advance value calculated using the compensation reference point used by the terminal will always be negative. Therefore, the positive / negative indicator bits for the compensation reference point or common compensation timing advance value can also be omitted, meaning it defaults to a negative value.

[0230] As described in Example 8, for terminals with positioning capabilities, it is only necessary to send them the common compensation timing advance value or compensation reference point coordinate parameters. Accordingly, referring to Table 3, if the terminal receives index number 1, it indicates that the signaling received by the terminal is the compensation reference point coordinates.

[0231] Table 3 Reference point coordinates and timing advance signaling composition.

[0232] As an optional implementation, the index numbers in Table 1, Table 2, or Table 3 above can be sent to the terminal via SIB signaling or RRC signaling, that is, the composition of the reference point or timing advance value can be configured to the terminal via SIB signaling or RRC signaling.

[0233] In this embodiment, the network side can use a lookup table to inform the terminal of the reference point coordinates and the composition of the timed advance signaling, which can save signaling overhead.

[0234] Example 10

[0235] This embodiment describes the type of signaling that carries the parameters (such as reference point coordinates, common timing advance value, etc.) involved in embodiments 1 to 9 above.

[0236] Method 1: Network devices can carry parameters such as the target cell / beam's service link common timing advance value / service link reference point coordinates, common compensation timing advance value / compensation reference point coordinates, and ATG reference point coordinates in broadcast information such as SIB1, OSI, and MIB, and send them to the terminal via unicast, broadcast, or multicast.

[0237] Method 2: If sent during the RRC connection phase, the network device may carry these parameters in at least one of the following: RRC information, RRCReconfiguration message, DCI, group DCI, MAC element, TAC, or send these parameters to the terminal with data transmission or in a separately allocated PDSCH bearer.

[0238] Method 2: When a terminal undergoes cell / beam / BWP handover, the network device can send these parameters to the terminal in the RRC Reconfiguration message and BWP-related signaling.

[0239] For example, when a beam or BWP switching occurs: If it is in the initial BWP phase, the parameters are sent in the RRC signaling corresponding to the initial BWP. The signaling format can be as follows: BWP ::= SEQUENCE { locationAndBandwidth INTEGER (0..37949), subcarrierSpacing SubcarrierSpacing, cyclicPrefix ENUMERATED { extended}OPTIONAL

[0240] ReferencePointCoordinateGroup ReferencePointCoordinateGroupL ist

[0241] }

[0242] in," ReferencePointCoordinateGroup "The fields can be used for the parameters involved in Examples 1-9, including reference point coordinates, common timing advance values, etc." ReferencePointCoordinateGroupList The field represents the specific values ​​of the reference point coordinates, common timing advance value, etc.

[0243] If the parameter is transmitted in a non-initial BWP phase, it is transmitted in the BWP Downlink Common signaling or the BWP Uplink Common signaling. The signaling format transmitted in a non-initial BWP phase can be as follows: BWP-DownlinkCommon ::= SEQUENCE { genericParameters BWP, pdcch-ConfigCommon SetupRelease { PDCCH-ConfigCommon} pdsch-ConfigCommon SetupRelease { PDSCH-ConfigCommon}

[0244] ReferencePointCoordinateGroup ReferencePointCoordinateGroupList

[0245] ...}

[0246] BWP-UplinkCommon ::= SEQUENCE {

[0247] genericParameters BWP, rach-ConfigCommon SetupRelease { RACH-ConfigCommon} pusch-ConfigCommon SetupRelease { PUSCH-ConfigCommon} pucch-ConfigCommon SetupRelease { PUCCH-ConfigCommon}

[0248] ReferencePointCoordinateGroup ReferencePointCoordinateGroupList

[0249] …

[0250] }

[0251] in," ReferencePointCoordinateGroup "The fields can be used for the parameters involved in Examples 1-9, including reference point coordinates, common timing advance values, etc." ReferencePointCoordinateGroupList The field represents the specific values ​​of the reference point coordinates, common timing advance value, etc.

[0252] The above signaling involves " ReferencePointCoordinateGroupList The specific format of the field is as follows (it should be understood that the following is only an example and not a limitation; other different field formats may appear depending on the different signaling combinations listed in the embodiments of this application): ReferencePointCoordinateGroupList ::= SEQUENCE { ServiceLinkReferencePoint BIT STRING (SIZE (n)), CompensatedReferencePoint BIT STRING (SIZE (n)), } The "ServiceLinkReferencePoint" field represents the coordinates of the service link reference point, and the "CompensatedReferencePoint" field represents the coordinates of the compensation reference point.

[0253] or, ReferencePointCoordinateGroupList ::= SEQUENCE { ServiceLinkReferencePoint BIT STRING (SIZE (n)), CompensatedReferencePoint BIT STRING (SIZE (n))OPTIONAL, ATGReferencePoint BIT STRING (SIZE (n)) OPTIONAL, } The "ATGReferencePoint" field represents the coordinates of the ATG reference point.

[0254] or, ReferencePointCoordinateGroupList ::= SEQUENCE { ServiceLinkCommonTimingAdvance BIT STRING (SIZE (n)), CompensatedReferencePoint BIT STRING (SIZE (n)), } The “ServiceLinkCommonTimingAdvance” field represents the common timing advance value for the service link.

[0255] or, ReferencePointCoordinateGroupList ::= SEQUENCE { ServiceLinkTimingValue BIT STRING (SIZE (n)), CompensatedTimingValue BIT STRING (SIZE (n)),} The "ServiceLinkTimingValue" field represents the timing advance value or reference point coordinates. "ServiceLinkTimingValue" contains a 1-bit indicator indicating whether the parameter is a common timing advance value for the service link or a service link reference point coordinate value, and also carries the corresponding common timing advance value / service link reference point coordinates. Similarly, the "CompensatedTimingValue" field represents the common compensation timing advance value or compensation reference point coordinates. "CompensatedTimingValue" contains a 1-bit indicator indicating whether the parameter is a common compensation timing advance value or a compensation reference point coordinate value, and also carries the corresponding common compensation timing advance value / compensation reference point coordinates.

[0256] It should be understood that different beams or cells can be distinguished in the protocol based on the BWP, transmission configuration indicator (TCI), or synchronization signal block (SSB); or in other words, beams or cells can be indicated based on BWP, TCI, or SSB. For example, the switching of beams or cells between a terminal and network equipment can be indicated by the switching of BWP, TCI, or SSB, so for the terminal and / or network equipment, the actual switching may be BWP, TCI, or SSB. Furthermore, the beams or cells described in this application can also be replaced with BWP, TCI, or SSB.

[0257] Example 11

[0258] This embodiment describes how, in handover scenarios between different beams or BWPs, the common timing advance value / service link reference point coordinates, common compensation timing advance value / compensation reference point coordinates, and ATG reference point coordinates of the target cell / beam are sent to the terminal via BWP-DownlinkDedicated signaling and BWP-UplinkDedicated signaling.

[0259] The format for issuing signaling can be as follows: BWP-DownlinkDedicated::= SEQUENCE { pdcch-Config SetupRelease { PDCCH-Config} pdsch-Config SetupRelease { PDSCH-Config} sps-Config SetupRelease { SPS-Config} radioLinkMonitoringConfig SetupRelease {RadioLinkMonitoringConfig}

[0260] ReferencePointCoordinateGroup ReferencePointCoordinateGroupL ist ...

[0262] }

[0263] BWP-UplinkDedicated ::= SEQUENCE {

[0264] pucch-Config SetupRelease { PUCCH-Config}

[0265] pusch-Config SetupRelease { PUSCH-Config}

[0266] configuredGrantConfig SetupRelease { ConfiguredGrantConfig}

[0267] srs-Config SetupRelease { SRS-Config}

[0268] beamFailureRecoveryConfig SetupRelease { BeamFailureRecoveryConfig}

[0269] ReferencePointCoordinateGroup ReferencePointCoordinateGroup List

[0270] …

[0271] }

[0272] in," ReferencePointCoordinateGroup "The fields can be used for the parameters involved in Examples 1-9, including reference point coordinates, common timing advance values, etc." ReferencePointCoordinateGroupList The field represents the specific values ​​of the reference point coordinates, common timing advance value, etc.

[0273] Example 12

[0274] Before initiating a BWP, beam, or cell handover, a measurement process may be triggered. Therefore, in this embodiment, the network-side delay compensation value of the target BWP, beam, or cell is sent through the neighbor cell measurement configuration and the corresponding RRC signaling during the handover.

[0275] For example, the network side sends the network-side delay compensation value for the target BWP, beam, or cell through the measurement signaling "MeasConfig" in RRC. The signaling format can be as follows: MeasObjectNR ::= SEQUENCE { carrierFreq ARFCN-ValueNR, ReferencePointCoordinateGroup ReferencePointCoordinateGroupList ... } in," ReferencePointCoordinateGroup "The fields can be used for the parameters involved in Examples 1-9, including reference point coordinates, common timing advance values, etc." ReferencePointCoordinateGroupList The field represents the specific values ​​of the reference point coordinates, common timing advance value, etc.

[0276] According to the handover signaling procedure, the serving link common timing advance value / serving link reference point coordinates, common compensation timing advance value / compensation reference point coordinates, and ATG reference point coordinates of the target BWP, beam, or cell are sent through the serving BWP, beam, or cell via the RRC registration message (RRCReconfiguration). An example of the specific signaling format is as follows: RRCReconfiguration ::= SEQUENCE { rrc-TransactionIdentifier RRC-TransactionIdentifier, criticalExtensions CHOICE {

[0277] rrcReconfiguration RRCReconfiguration-IEs, criticalExtensionsFuture SEQUENCE {} } } in," rrcReconfiguration "This field indicates the RRC registration signaling." RRCReconfiguration-IEs The specific format of the field can be as follows: RRCReconfiguration-IEs : := SEQUENCE { radioBearerConfig RadioBearerConfig OPTIONAL, --Need M

[0278] ReferencePointCoordinateGroup ReferencePointCoordinateGroupList

[0279] secondaryCellGroup OCTET STRING (CONTAINING CellGroupConfig)OPTIONAL, -- Need M

[0280] measConfig MeasConfig OPTIONAL, -- Need M

[0281] lateNonCriticalExtension OCTET STRING OPTIONAL, nonCriticalExtension SEQUENCE {} OPTIONAL } Example 13 This embodiment describes how, when it is necessary to send ATG reference point coordinates, the satellite position coordinates (or part of the ephemeris information) can be replaced with the ATG reference point coordinates and sent to the terminal, which can save signaling overhead.

[0282] In NTN satellite communication, the network side sends satellite position coordinates or ephemeris information to the terminal. Therefore, when the terminal switches to ATG communication, the satellite position coordinates or ephemeris information can be replaced with ATG reference point coordinates.

[0283] like Figure 19 As shown, ATG reference point coordinates / satellite position coordinates occupy the same or partially the same signaling bits, and can be sent together or separately with other reference point coordinates, common timing advance values ​​(service link reference point coordinates or service link common timing advance values ​​or compensation reference point coordinates or common compensation timing advance values).

[0284] In this way, terminals with positioning capabilities can still use the ATG reference point coordinates and their own location coordinates to calculate the round-trip time delay between the terminal and the base station, and determine the timing adjustment value in advance.

[0285] Furthermore, one bit can be used to indicate to the terminal whether the network side is sending ATG reference point coordinates or satellite position coordinates / ephemeris information, such as... Figure 20 As shown.

[0286] Example 14

[0287] This embodiment describes the method for calculating TA.

[0288] In existing technologies, the timing advance used by the terminal is... Among them, N TA It is the TA adjustment value obtained by the terminal based on parameters indicated by the network side, such as the TA adjustment value calculated by the terminal based on the common timing advance value and / or reference point coordinates and / or the terminal's location information sent by the network side in this invention patent. N TAoffset This indicates the timing interval for uplink to downlink transmission, and is sent to the terminal via SIB information. For FDD mode, NT... Aoffset =0; TDD mode, N TAoffset =624. This time interval allows the base station sufficient time to switch between receiving uplink signals and transmitting downlink signals. Ts represents 1 / (15e3) 2048) seconds. μ is related to the subcarrier spacing, i.e., the subcarrier spacing is... kHz.

[0289] In this embodiment, the TA adjustment value calculated by the terminal based on the common timing advance value sent by the network side and / or the reference point coordinates and / or the terminal's location information can be compared with a fixed value (e.g., N). TAoffset The sum of these values ​​gives the timing advance that the terminal can use.

[0290] In this application embodiment, the fixed value includes, but is not limited to, the following three implementation methods: Method 1: The fixed value is the offset.

[0291] The offset can be related to one or more of the following factors: 1) Duplex modes include two types: Time Division Duplex (TDD) mode and Frequency Division Duplex (FDD) mode; 2) Positioning or location error of the second network device (e.g., satellite); It should be understood that positioning error and location error are just different ways of saying the same thing.

[0292] 3) Terminal position error or positioning error.

[0293] Of course, the above three factors are just examples and not limitations. In practical applications, they can also be related to other factors.

[0294] In one possible design, the network side can send an offset (e.g., a time offset) to the UE indicating the quotient of the second network device's position error or positioning error and the speed of light, i.e., positioning error / speed of light, or an offset of twice the quotient of the second network device's position error or positioning error and the speed of light, i.e., 2 Positioning error / speed of light.

[0295] It should be understood that the speed of light refers to the speed at which light waves travel through air or outer space; for example, the speed of light is often expressed as 3. 10 8 .

[0296] Optionally, the offset can be positive, negative, or 0. That is, the offset sent from the network side to the terminal can be: +(positioning error / speed of light), or -(positioning error / speed of light), or +(2... Positioning error / speed of light), or -(2 Positioning error / speed of light).

[0297] When it's necessary to avoid the terminal receiving an excessively large TA value that could cause ISI (Inter-Signal Instability), the offset can be negative; when it's necessary to avoid the terminal receiving a signal from the network device too late due to an excessively small TA value, the offset can be positive. Alternatively, the network side can agree with the terminal that the transmitted offset will be positive, and the terminal will take the negative value of the received offset before using it.

[0298] The unit of offset can be nanosecond (ns), microsecond (us), millisecond (ms), or 16. Ts / 2 μ The embodiments in this application are not limited to these.

[0299] Understandably, the position error or positioning error of the second network device can be understood as the deviation between the position coordinates (which can be represented by ephemeris information or three-dimensional coordinates) of the second network device and its actual position due to perturbation effects. This position error or positioning error can be the maximum possible deviation between the position coordinates and the actual position of the second network device. This position error or positioning error can also be referred to as ephemeris error.

[0300] Understandably, the aforementioned terminal position error or positioning error represents the position deviation that occurs when the terminal uses a positioning system or positioning method to locate its own position, that is, the deviation distance or the maximum possible deviation distance between the terminal position coordinates obtained by positioning and the actual position coordinates.

[0301] Understandably, the network side and the terminal can agree that the network side sends a positive offset to the terminal, and the terminal subtracts the calculated TA adjustment value from the offset to obtain the timing advance that the terminal can use; equivalently, the network side sends a negative offset to the terminal, and the terminal adds the calculated TA adjustment value to the offset to obtain the timing advance that the terminal can use.

[0302] In summary, the aforementioned fixed value can be an offset, which the network side can send / configure to the terminal. The terminal adds or subtracts the calculated TA adjustment value from this offset to obtain the timing advance that the terminal can use. The TA adjustment value calculated by the terminal can be the sum of the round-trip time of the serving link and the common compensation timing advance value (or difference).

[0303] In another possible design, the network side can send the UE a value that can determine the position error or positioning error of the offset.

[0304] The position error or positioning error value here can be the position error or value of the second network device (such as a satellite) and / or the position error of the terminal. Below, position_err is used to represent the position error or positioning error value. The unit of position_err can be meters, and position_err is used to indicate the possible position error of the second network device.

[0305] After receiving position_err, the terminal calculates the offset mentioned above based on position_err.

[0306] For example, the terminal device can calculate the value of the offset to be used by the terminal using any of the following methods: 1) -2 position_err / speed of light, i.e., -2 The quotient of position_err and the speed of light; 2) +2 position_err / speed of light, +2 The quotient of position_err and the speed of light; 3) position_err / speed of light, which is the quotient of position_err and speed of light; 4) -position_err / speed of light, which is the quotient of -position_err and speed of light.

[0307] Similarly, negative values ​​can be used to avoid ISI, and positive values ​​can be used to avoid excessively small TA values. Ultimately, the terminal can adjust the calculated TA value along with this offset (e.g., -2). The timing advance usable by the terminal is obtained by adding or subtracting the position_err / speed of light. The TA adjustment value calculated by the terminal can be the sum of the round-trip time of the service link and the common compensation timing advance value (or the difference mentioned above).

[0308] It should be noted that the offset may include one or more of the following: a TDD or FDD mode related portion, a location error portion of the second network device, and a location error portion of the terminal. If the offset includes both the TDD or FDD mode related portion and the location error portion of the second network device and / or the terminal's location error portion, the network side can either combine (e.g., add / subtract) these portions before sending them to the terminal or send these portions separately to the terminal. Accordingly, the terminal can directly use the combined offset; or, after receiving the above portions, the terminal can combine (add / subtract) them to use as the final offset. The value of this offset can be agreed upon through a protocol or sent / configured to the terminal by the network side.

[0309] Method 2: The fixed value is a numerical offset.

[0310] As described above (e.g., Example 3), the common compensation timing advance value (i.e., the round-trip time delay between the satellite and the compensation reference point) sent by the network side to the terminal replaces the location coordinates of the compensation reference point. When the compensation reference point is on the power supply link, the common compensation timing advance value needs to be taken as positive; when the compensation reference point is on the service link, the common compensation timing advance value needs to be taken as negative.

[0311] To improve the flexibility of the solution, in this embodiment, the terminal may not know whether the compensation reference point is on the feeder link or the service link. Instead, the network side sends a common timing parameter to the terminal for the terminal to determine the common compensation timing advance value. The network side can send / configure a numerical offset to the terminal. After receiving the common timing parameter, the terminal subtracts or adds it to the numerical offset to obtain the common compensation timing advance value used by the terminal, i.e.: Common compensation timing advance value = common timing parameter + numerical offset; or, Common compensation timing advance value = Common timing parameter - Numerical offset.

[0312] The common compensation timing advance value calculated from the common timing parameter + / - numerical offset may be positive or negative.

[0313] Accordingly, the terminal can sum the round-trip time of the service link, the common timing parameter, and the ± numerical offset in the NTN to obtain the TA to be used. Here, ± represents + or -. That is: TA = Round-trip time of the service link (or the timing advance adjustment value of the service link). +Public compensation time advance value =Round-trip time of service link + common timing parameters ± numerical offset.

[0314] For example, when the numerical offset is a positive value, the common timing advance value used by the terminal can be calculated as: Common Timing Parameter - Numerical Offset. The magnitude of this numerical offset can be agreed upon through the protocol or sent / configured to the terminal by the network side. For example, if the common timing parameter sent by the transmitter is in the range of 0 to 10, the receiver subtracts it from a numerical offset (assuming it is 5) to obtain a common timing advance value in the range of -5 to 5. This method is equivalent to shifting the common timing parameter sent by the transmitter by a numerical offset at the receiver, thereby obtaining the range of common timing advance values ​​to be used.

[0315] Understandably, this method can also be used to send other numerical parameters, allowing the sender to transmit positive or negative values, and the receiver to shift the numerical range, achieving the effect of representing a range using positive / negative values. This improves the flexibility of the solution while simplifying the complexity of the sender.

[0316] Method 3: Fixed values ​​include two parts: offset and numerical offset.

[0317] If the network side sends both the offset to the terminal and agrees on a numerical offset value with the terminal (or the network side sends a numerical offset value to the terminal), then the terminal side can sum the round-trip time of the service link in the NTN, the common timing parameter, the ± numerical offset, and the ± offset to obtain the TA to be used, i.e.: TA = Round-trip time of service link + Common compensation timing advance value ± Offset =Round-trip delay of service link + Common timing parameter ± Numerical offset ± Offset amount.

[0318] It should be understood that the above three methods are merely examples of fixed values ​​and not limitations. In practical applications, the possibility of other implementation methods cannot be ruled out.

[0319] Furthermore, fixed values ​​such as offsets, common timing parameters, or numerical offsets can be carried in at least one broadcast message among system information blocks (SIBs), other system information (OSIs), and master information blocks (MIBs), and broadcast or multicast to the terminal by the network device. In addition, if offsets, common timing parameters, or numerical offsets are sent during the radio resource control (RRC) connection phase, the network side can carry these information in at least one message among RRC information, RRCReconfiguration messages, downlink control information (DCIs), group DCIs, media access control (MAC) control elements (CEs), and timing advance commands (TACs), or send them to the UE with data transmission or in a separately allocated PDSCH bearer.

[0320] The following provides specific examples illustrating signaling design for offset, common timing parameters, and numerical offset.

[0321] Example 1: The network side can add a new variable field, such as T-offset, to the Random Access Generic (RACH-ConfigGeneric) parameter to represent the offset. The RACH-ConfigGeneric parameter is typically sent to the UE in broadcast or RRC messages, providing the UE with the generic parameters used during random access. For example: RACH-ConfigGeneric ::= SEQUENCE { prach-ConfigurationIndex INTEGER (0..255), T-offset INTEGER (0.. 511), ... } Optionally, the network side can determine the range of T-offset based on the maximum possible distance value of the ephemeris error, satellite position error, or satellite positioning error. For example, taking a maximum ephemeris error or satellite position error of 10km as an example, the T-offset is set to 16km. Ts / 2 μ As a unit of measurement, T-offset ranges from 0 to 511 and requires 9 bits of signaling to represent.

[0322] It is understandable that T-offset can have different ranges of representation depending on the maximum satellite positioning error range and the time unit. For example, after receiving the T-offset, the terminal subtracts the T-offset value from the TA adjustment value obtained by the terminal to finally obtain the timing advance TA value used by the terminal, i.e., TA = (N TA -T-offset) 16 Ts / 2 μ ； Alternatively, subtract the T-offset value and the timing interval N from the TA adjustment value obtained from the terminal. TAoffset Finally, the timing advance TA value used by the terminal is obtained, that is, TA = (N TA +N TAoffset -T-offset) 16 Ts / 2 μ Among them, N TA It is the TA adjustment value obtained by the terminal based on the parameters indicated by the network side. For example, in the embodiments of this application, the TA adjustment value is calculated by the terminal based on at least one of the common timing advance value, common compensation timing advance value, reference point coordinates, and terminal location information sent by the network side.

[0323] Optionally, the RACH-ConfigGeneric parameter can be transmitted in messages such as SIB1, RRC Setup, RRC Reconfiguration, and RRC Resume, which can ensure that the terminal can receive values ​​such as offset, common timing parameters, and numerical offset during the initial access phase and connection state switching, and establish accurate uplink time synchronization.

[0324] Example 2: The network side can send the distance value that can determine the ephemeris error, position error or positioning error of the offset to the terminal through the random access generic configuration (RACH-ConfigGeneric) parameter. Here, D-offset represents the distance value of the ephemeris error, position error or positioning error of the offset.

[0325] RACH-ConfigGeneric ::= SEQUENCE {

[0326] prach-ConfigurationIndex INTEGER (0..255), D-offset INTEGER (0.. 1000), ... } This example adds a new variable field, D-offset, to the RACH-ConfigGeneric parameter, which represents the distance value that determines the ephemeris error, position error, or positioning error of the offset.

[0327] In this example, the network side can determine the range of D-offset based on the maximum possible distance value of the ephemeris error, satellite position error, or satellite positioning error. For example, taking a maximum ephemeris error or satellite position error of 10 km as an example, the D-offset is measured in meters, and its range is 0 to 1000, requiring 10 bits of signaling to represent it. 10 bits can represent the range 0 to 1023, where 1001 to 1023 is reserved and can also be used for other indication purposes.

[0328] It is understandable that D-offset can have different ranges of representation if different maximum satellite positioning error ranges and distance units are assumed.

[0329] For example, after receiving the D-offset, the terminal can subtract the D-offset / speed of light from the TA adjustment value obtained by the terminal, or subtract the speed of light from the TA adjustment value. D-offset / speed of light / (16.64T) c / 2 u ) This allows us to obtain the timing advance TA value used by the terminal. " indicates rounding up. That is: TA = N TA 16 Ts / 2 μ -D-offset / speed of light; or, TA = (N TA - D-offset / speed of light / (16.64T) c / 2 u ) +N TAoffset ) 16 Ts / 2 μ .

[0330] Where Tc represents the unit of time. , Hz, From the definition of Ts above, we can see that... ,Right now , , .

[0331] Example 3: To ensure that the terminal obtains a more accurate TA value to request access to the communication system, the network side can send a common compensation timing advance value to the terminal through the Random Access Generic (RACH-ConfigGeneric) parameter. Here, TA-common represents the common compensation timing advance value. RACH-ConfigGeneric ::= SEQUENCE { prach-ConfigurationIndex INTEGER (0..255), TA-common INTEGER (-4155513.. 4155513), ... } In this example, the network side adds a new variable field, such as TA-common, to the RACH-ConfigGeneric parameter to represent the parameter value used to determine the common compensation timing advance value or the common timing advance value.

[0332] Optionally, the network side can determine the representation range of TA-common based on the satellite's maximum possible orbital altitude and the possible minimum communication angle.

[0333] For example, assuming the orbital altitude is a GEO orbit and the minimum beacon angle is 10 degrees, at 16.64°T... c / 2 u Since the unit of measurement is 23 bits, the range of TA-common needs to be -4155513 to +4155513, requiring 23 bits of signaling to represent it. The range that 23 bits can represent is -4194303 to +4194303. The ranges -4194303 to -4155513 and 4194303 to 4155513 are reserved and can be used for other indication purposes. It is understandable that the indication range of TA-common can differ depending on the assumed satellite orbital altitude, minimum elevation angle, and time unit of measurement.

[0334] After receiving TA-common, the terminal can calculate the round-trip time of the service link based on the terminal's location and the satellite's location, and add it to the time length represented by TA-common to obtain the TA adjustment value.

[0335] It should be understood that TA-common can represent either the advance value of the public compensation timing or the public propagation delay that the terminal needs to compensate for.

[0336] It should be understood that TA-common can represent positive, negative, and zero values. A positive value indicates that the uplink signal is sent in advance, while a negative value indicates that the uplink signal is sent in a delayed manner.

[0337] Example 4: To save signaling bits, the network side can combine and indicate common compensation timing advance signaling based on the orbital altitude range. For example: RACH-ConfigGeneric ::= SEQUENCE { prach-ConfigurationIndex INTEGER (0..255), TA-common-LEO BIT STRING (SIZE(20)), TA-common-complement BIT STRING (SIZE(3)) OPTIONAL, ... } In this example, the network side adds two new variable fields to the RACH-ConfigGeneric parameter: TA-common-LEO (Low Orbit Common Timing Advance) and TA-common-complement (Low Orbit Common Timing Advance Supplement). These fields are used to determine the common compensation timing advance value or the common propagation delay that the terminal needs to compensate for. TA-common-complement is optional; the network side can choose to send or not send this parameter. The network side can decide whether to send the TA-common-complement parameter based on the orbital altitude of the second network device, as illustrated in the example below.

[0338] Optionally, the network side can determine the representation range and number of bits for TA-common-LEO and TA-common-complement based on the satellite's orbital altitude range and the possible minimum communication angle.

[0339] For example, in scenarios where the orbital altitude is no higher than 1200km, the network side can send only TA-common-LEO signaling (20 bits), i.e., without sending TA-common-complement. In this case, only 20 bits of signaling are needed to represent the common compensation timing advance value, which is used to represent the range of -320609 to +320609. The range that 20 bits can indicate is -524287 to +524287. Among them, the ranges of -524287 to -320609 and 320609 to 524287 are reserved and can also be reserved for other indication purposes.

[0340] For example, in scenarios with an orbital altitude greater than 1200km, the network side can send TA-common-LEO and TA-common-complement signaling (3 bits) to the UE. TA-common-LEO represents the high-order bits, and TA-common-complement represents the low-order bits. TA-common-LEO and TA-common-complement together form a 23-bit signaling, representing the range -4155513 to 4155513. The range that 23 bits can represent is -4194303 to +4194303. The ranges -4194303 to -4155513 and 4194303 to 4155513 are reserved and can also be used for other indication purposes.

[0341] After receiving the common compensation timing advance values ​​represented by TA-common-LEO and TA-common-complement, the terminal can calculate the round-trip time of the service link based on the terminal's location and the satellite's location. It then adds this to the time length represented by the common compensation timing advance value to obtain the TA adjustment value. This signaling transmission method provides flexibility and saves signaling bits in scenarios with low orbital altitudes.

[0342] Example 5: To save signaling bits in scenarios with different orbital altitudes, the network side can provide separate indications for the common compensation timing advance signaling based on the orbital altitude range. For example: RACH-ConfigGeneric := SEQUENCE { prach-ConfigurationIndex INTEGER (0..255), TA-common-LEO-600 INTEGER (-197800.. 197800) OPTIONAL, TA-common-LEO-1200 INTEGER (-320609.. 320609) OPTIONAL, TA-common-GEO INTEGER (-4155513.. 4155513)OPTIONAL, ... } In this example, the network side adds three new variable fields to the RACH-ConfigGeneric parameter: LEO 600 common timing advance TA-common-LEO-600, LEO 1200 common timing advance TA-common-LEO-1200, and geostationary orbit common timing advance TA-common-GEO. These represent parameter values ​​used to determine the common compensation timing advance value or the common propagation delay that the terminal needs to compensate for. Among these, A-common-LEO-600, TA-common-LEO-1200, and TA-common-GEO are all optional; that is, the network side can choose to send only one, only two, or all of these three parameters.

[0343] Optionally, the network side can determine the representation range and number of bits for TA-common-LEO-600, TA-common-LEO-1200, and TA-common-GEO based on the satellite's orbital altitude range and the possible minimum communication angle. Specifically, TA-common-LEO-600 represents the parameters related to the common-compensation timing advance value at orbital altitudes not exceeding 600 km, TA-common-LEO-1200 represents the parameters related to the common-compensation timing advance value at orbital altitudes not exceeding 1200 km, and TA-common-GEO represents the parameters related to the common-compensation timing advance value at orbital altitudes not exceeding 36000 km.

[0344] For example, in scenarios where the orbital altitude is no higher than 600km, the network side can send TA-common-LEO-600 signaling (19 bits), meaning it does not send TA-common-LEO-1200 and TA-common-GEO. In this case, only 19 bits of signaling are needed for the terminal to determine the common compensation timing advance value, representing a range of -197800…+197800. The 19 bits can indicate a range of -262143 to +262143, where the ranges of -262143 to -197800 and 197800 to 262143 are reserved and can also be used for other indication purposes.

[0345] For example, in scenarios where the orbital altitude is greater than 600km but not greater than 1200km, the network side can send TA-common-LEO-1200 signaling (20 bits) to the UE, i.e., without sending TA-common-LEO-600 and TA-common-GEO. In this case, only 20 bits of signaling are sent for the terminal to determine the common compensation timing advance value, which represents a range of -320609…320609. The 20 bits can indicate a range of -524287 to +524287, where the ranges of -524287 to -320609 and 320609 to 524287 are reserved and can also be used for other indication purposes.

[0346] For example, in scenarios with orbital altitudes higher than 1200km, the network side needs to send TA-common-GEO signaling (23 bits), meaning it does not send TA-common-LEO-600 and TA-common-LEO-1200. In this case, 23 bits of signaling are needed for the terminal to determine the common compensation timing advance value, representing a range of -4155513 to +4155513. The range that 23 bits can represent is -4194303 to +4194303. The ranges -4194303 to -4155513 and 4194303 to 4155513 are reserved and can also be used for other indication purposes.

[0347] After receiving the common compensation timing advance value represented by any one or more of TA-common-LEO-600, TA-common-LEO-1200 or TA-common-GEO, the terminal can calculate the round-trip delay of the service link based on the terminal location and satellite location, and add it to the time length represented by the common compensation timing advance value to obtain the TA adjustment value.

[0348] Example 6: The network side can send parameter values ​​(i.e., common timing parameters, denoted here as TA-common-timing) to the terminal through the Random Access Generic Configuration (RACH-ConfigGeneric) parameter to determine the common compensation timing advance value or the common timing advance value: RACH-ConfigGeneric ::= SEQUENCE { prach-ConfigurationIndex INTEGER (0..255), TA-common-timing INTEGER (0... 8311026), ... } In this example, the network side adds a new variable field, TA-common-timing, to the RACH-ConfigGeneric parameter. This parameter is used to determine the common compensation timing advance value or the common timing advance value.

[0349] Optionally, the network side can determine the range of representation for TA-common-timing based on the satellite's maximum possible orbital altitude and the possible minimum communication angle.

[0350] For example, assuming the orbital altitude is a GEO orbit and the minimum beacon angle is 10 degrees, at 16.64°T... c / 2 u Since it is a unit of measurement, the range of TA-common-timing needs to be 0 ~ 8311026, which requires 23 bits of signaling to represent. The range that 23 bits can represent is 0 ~ 8388607, of which the range 8311027 ~ 8388607 is reserved and can also be used for other indication purposes.

[0351] It is understandable that the indication range of TA-common-timing can vary depending on the satellite orbital altitude, minimum elevation angle, and time unit.

[0352] After receiving the common timing parameter TA-common-timing, the terminal subtracts it from the numerical offset to obtain the common compensation timing advance value or the common timing advance value.

[0353] For example, assuming the numerical offset is 4155513 (the numerical offset can be agreed upon through the protocol or configured by the network side to the UE), after receiving TA-common-timing, the terminal obtains the common compensation timing advance value by subtracting 4155513 from TA-common-timing. The range of the common compensation timing advance value is -4155513 to +4155513. This method is equivalent to performing an offset operation on the received TA-common-timing value, i.e., TA-common-timing – numerical offset. Here, we take a numerical offset of 4155513 as an example, but in actual use, it is not limited to this value. As another example, after receiving TA-common-timing, the terminal can calculate the common compensation timing advance value, then calculate the round-trip time of the service link based on the terminal's location and satellite location, and add it to the time length represented by the common compensation timing advance value to obtain the TA adjustment value.

[0354] Furthermore, the transmission signaling methods described above can be combined.

[0355] For example, the network side can add three new variable fields to the RACH-ConfigGeneric parameter: LEO 600 common timing parameter TA-common-timing-LEO-600, LEO 1200 common timing parameter TA-common-timing-LEO-1200, and geostationary orbit common timing parameter TA-common-timing-GEO. These represent the common timing parameter values ​​used to determine the common compensation timing advance value or the common propagation delay that the terminal needs to compensate for. RACH-ConfigGeneric ::= SEQUENCE { prach-ConfigurationIndex INTEGER (0..255), TA-common-timing-LEO-600 INTEGER (0.. 395600) OPTIONAL, TA-common-timing-LEO-1200 INTEGER (0.. 641218) OPTIONAL, TA-common-timing-GEO INTEGER (0.. 8311026) OPTIONAL, ... } Optionally, the representation range and number of bits for TA-common-timing-LEO-600, TA-common-timing-LEO-1200, and TA-common-timing-GEO can be determined based on the satellite's orbital altitude range and the possible minimum communication angle. Specifically, TA-common-timing-LEO-600 represents common timing parameters related to common compensated timing advance values ​​at orbital altitudes not exceeding 600 km; TA-common-timing-LEO-1200 represents common timing parameters related to common compensated timing advance values ​​at orbital altitudes not exceeding 1200 km; and TA-common-timing-GEO represents common timing parameters related to common compensated timing advance values ​​at orbital altitudes not exceeding 36000 km. All three parameters (TA-common-timing-LEO-600, TA-common-timing-LEO-1200, and TA-common-timing-GEO) are optional; the network can choose not to transmit any of these three parameters and instead transmit only one of them.

[0356] For example, in scenarios where the orbital altitude is no higher than 600km, the minimum beacon angle is 10 degrees, with 16.64T. c / 2 u For units of measurement, the network side can send TA-common-timing-LEO-600 signaling (19 bits), meaning it will not send TA-common-timing-LEO-1200 and TA-common-timing-GEO. In this case, only 19 bits of common timing parameter signaling need to be sent for the terminal to determine the common compensation timing advance value, representing a range of 0 to 395600. The 19 bits can indicate a range of 0 to 524287, where the range 395601 to 524287 is reserved for other indication purposes. Similarly, TA-common-timing-LEO-1200 and TA-common-timing-GEO signaling use 20 bits and 23 bits respectively to represent ranges of 0 to 641218 and 0 to 8311026.

[0357] For example, suppose that the common timing parameters for different orbital parameter ranges have different numerical offsets: the numerical offset value corresponding to TA-common-timing-LEO-600 is 197800, the numerical offset value corresponding to TA-common-timing-LEO-1200 is 320609, and the numerical offset value corresponding to TA-common-timing-GEO is 4155513. After receiving TA-common-timing-LEO-600, the terminal obtains the common compensation timing advance value through TA-common-timing-LEO-600 - 197800, and the range of the common compensation timing advance value is -197800 to 197800.

[0358] For example, the indication ranges of TA-common-timing-LEO-600, TA-common-timing-LEO-1200, or TA-common-timing-GEO may differ depending on the satellite orbital altitude, minimum elevation angle, and time unit. After receiving the common timing parameter TA-common-timing-LEO-600, TA-common-timing-LEO-1200, or TA-common-timing-GEO, the terminal subtracts it from the corresponding numerical offset to obtain the common compensation timing advance value or the common timing advance value. The terminal can calculate the round-trip time of the service link based on its location and the satellite's location, and add it to the time length represented by the common compensation timing advance value to obtain the TA adjustment value.

[0359] The following are some more detailed examples to illustrate how the terminal calculates the TA value to be used based on the terminal location, satellite location, public compensation timing advance value, etc.

[0360] Assuming 16.64T c / 2 u If the unit of measurement is quantized, then the round-trip latency of the service link is quantified as follows: For NT service = RTD service / (16·64·T c / 2 u ) = (2 distance service / speed of light) / (16·64·T c / 2 u ) ; (1) RTD service This represents the round-trip time delay between the terminal and the satellite, which is equal to the quotient of twice the distance between the terminal and the satellite and the speed of light. " indicates rounding down to the nearest integer.

[0361] The common compensation timing advance value obtained by the terminal is NT. common Then, the TA amount obtained by the terminal when sending the random access preamble or uplink data is: (2) If we consider the offset T-offset, common timing parameters, and numerical offset, the TA amount used by the terminal is: (3) If we consider the position error D-offset, common timing parameters, and numerical offset, the TA quantity used by the terminal is: TA = (NT) service ·+ NT common - (2 D-offset / speed of light) / (16.64T) c / 2 u ) ) 16 64T c / 2 u (4) It can be seen that formula (4) is based on (2 D-offset / speed of light) / (16.64T) c / 2 u ) The T-offset in formula (3) is partially replaced, representing the time uncertainty caused by satellite positioning error subtracted from the timing advance value to be used by the terminal. That is, the timing uncertainty is twice the possible satellite positioning error divided by the speed of light, and then (16·64·T) c / 2 u The time unit is rounded up for quantization.

[0362] The TA quantity used by the terminal can also be: TA = (NT) service ·+ TA-common-timing (numerical offset) 16 64 T c / 2 u (5) Among them, the common-common-timing numerical offset is replaced by the NT value for common-common-timing advance. common .

[0363] The TA quantity used by the terminal can also be: TA = (NT) service ·+ TA-common-timing-numerical offset-T-offset) 16 64 T c / 2 u (6) The TA quantity used by the terminal can also be: TA = (NT) service ·+ TA-common-timing-numerical offset- (2 D-offset / speed of light) / (16.64T) c / 2 u ) ) 16 64 T c / 2 u (7) It should be understood that if the TA quantity is obtained by calculation using other time units, then it is only necessary to replace (16·64·T) in the above formulas (1)~(7) with the new time unit. c / 2 u Any time unit is acceptable. For example, use 64·T. c / 2 uIf the unit is dimensional, then in the above formulas (1) to (7), (16·64·T) c / 2 u The time unit has been replaced with 64·T c / 2 u Any time unit is acceptable.

[0364] If NT is calculated service At 64·T c / 2 u The public compensation timing advance value NT is obtained in units of time. common Common timing parameters and numerical offsets are based on 16.64T. c / 2 u It is a unit of time. Therefore, NT... service = RTD service / (64·T c / 2 u ) = (2 distance service / speed of light) / ( 64·T c / 2 u ) Therefore, the TA quantity used by the terminal is: TA = (NT) service / 16·+ NT common ) 16 64 T c / 2 u (8) If we consider the offset T-offset or position error D-offset, the common timing parameters, and the numerical offset, then the TA quantity used by the terminal is: TA = (NT) service / 16·+ NT common -T-offset) 16 64 T c / 2 u (9) or, TA = (NT) service / 16·+ NT common - (2 D-offset / speed of light) / (16.64T) c / 2 u ) ) 16 64 T c / 2 u (10) Similarly, formula (10) is based on (2 D-offset / speed of light) / (16.64T) c / 2 u ) In the partial substitution formula (9), T-offset represents the timing uncertainty caused by satellite positioning error subtracted from the timing advance value to be used by the terminal. That is, the timing uncertainty is twice the possible satellite positioning error divided by the speed of light, and then (16·64·T) c / 2 u The time unit is rounded up for quantization.

[0365] The TA quantity used by the terminal can also be: TA = (NT) service / 16·+ TA-common-timing-numerical offset) 16 64 T c / 2 u (11) In this context, the common-common-timing value is replaced by (TA-common-timing - numerical offset) instead of NT. common .

[0366] The TA quantity used by the terminal can also be: TA = (NT) service / 16·+ TA-common-timing- Numerical offset (T-offset) 16 64 T c / 2 u (12) The TA quantity used by the terminal can also be: TA = (NT) service / 16·+ TA-common-timing-numerical offset- (2 D-offset / speed of light) / (16.64T) c / 2 u ) ) 16 64 T c / 2 u (13) The following section describes the impact of cell handover, beam switch, gateway switch, and satellite switch on advance public compensation timing or advance public timing.

[0367] 1. Cell handover: 1) During the Cell handover procedure, the UE performs measurements and reports the neighboring cell channel quality according to the network side's instructions. Then, the gNB where the source cell is located (hereinafter referred to as the source gNB, which may be the same as or different from the gNB where the target cell is located) sends RRCReconfiguration signaling to the UE. As can be seen from the above signaling, the common compensation timing advance or common timing advance signaling exists in RRCReconfiguration. Therefore, the common compensation timing advance or common timing advance of the target cell can be carried in RRCReconfiguration. For non-random access handover (RACHless handover), the source gNB also sends RRCReconfiguration signaling to the UE, and can also send the common compensation timing advance value or common timing advance value of the target gNB to the UE.

[0368] 2) The UE receives the SIB1 of the target cell and can also obtain the common compensation timing advance or common timing advance of the target cell.

[0369] 2. Satellite switch: You can refer to the process of cell handover, which will not be repeated here.

[0370] 3. Beam Switch: When the source beam and target beam belong to the same cell, the common compensation timing advance or common timing advance is broadcast in SIB1 and is cell-level signaling. Therefore, when performing a beam switch, both beams use the same common compensation timing advance or common timing advance, and timing jumps will not occur. (If the common compensation timing advance or common timing advance is at the beam level, the network may compensate different delay values ​​for different beams, leading to timing jumps. In this case, the common compensation timing advance value or common timing advance value needs to be included in the BWP handover signaling, for example, in the BWP-UplinkDedicated signaling.)

[0371] 4. Gateway switch:

[0372] When a soft gateway switch occurs, meaning the UE can simultaneously establish connections with two gateways and receive messages from both gateways, this gateway switch scenario can be equated to a cellhandover process. In this case, the common compensation timing advance value or common timing advance value of the target gateway can be sent to the UE in the RRCReconfiguration signaling.

[0373] When a hard gateway switch occurs, meaning a UE can only establish a connection with one gateway at a time, the feeder link latency will change when a UE disconnects from one gateway and simultaneously establishes a connection with another (i.e., a hard switch occurs). The gNB can send the UE the common-compensated timing advance value or common-time advance value it uses at the target gateway, or the difference between the current common-compensated timing advance value and the one it uses, before the gateway switch. For example, if all UEs in an entire beam or cell need to update their common-compensated timing advance value or common-time advance value, the RRCReconfiguration signaling can be used to carry these parameters for updating.

[0374] Furthermore, when a soft or hard handover occurs at a gateway, the gNB uses MAC CE signaling to send the target gateway's common compensation timing advance value or common timing advance value, or the difference between the common compensation timing advance value or common timing advance value currently in use, to the UE.

[0375] In certain special scenarios, sending the common compensation timing advance difference or the common timing advance value difference requires the same number of bits as sending the complete common compensation timing advance value or the complete common timing advance value. For example, if the network side performs timing compensation on the uplink signal before the handover but not after the handover, then the complete round-trip time of the feeder link needs to be represented. In this case, the number of bits required for the common compensation timing advance difference is the same as that required for the complete common compensation timing advance value. If the protocol does not support these special scenarios, then sending the common compensation timing advance difference can save signaling overhead compared to sending the complete common compensation timing advance value.

[0376] The validity of the public compensation advance value or the public advance value is described below.

[0377] If SIB1 carries the common compensation timing advance value or the common timing advance value, the SIB1 update cycle determines the maximum error of the common compensation timing advance value or the common timing advance value. The error comes from the relative motion between the satellite and the gateway.

[0378] System messages (including SIB1) are only updated at the start frame of the modification period, and the start frame of the modification period must meet the following conditions: SFN mod m = 0; Where m represents the number of system frames included in the change cycle length, SFN represents the system frame number, and mod represents the modulo operation; m = modificationPeriodCoeff defaultPagingCycle, unit: frame; modificationPeriodCoeff= 2 / 4 / 8 / 16; defaultPagingCycle=32 / 64 / 128 / 256.

[0379] Among them, modificationPeriodCoeff and defaultPagingCycle can be configured through SIB1.

[0380] It can be seen that the minimum change cycle is 64 frames = 640 ms.

[0381] Assume the common compensation timing advance value indicates the difference between the feeder link round-trip time and the network-side timing compensation value for uplink data. If the satellite and gateway become increasingly closer, the common compensation timing advance value may be larger, potentially leading to preamble or uplink data arriving earlier, resulting in inter-symbol interference (ISI).

[0382] To avoid ISI (Intermittent Separation and Interference), a common compensation timing advance value or a common timing advance value corresponding to the start time of the next update cycle can be sent at the start time of a certain update cycle. This results in a smaller common compensation timing advance value or common timing advance value being sent, causing the UE's preamble or uplink data to arrive at the network side later, thus avoiding ISI. For example, if the update cycle is 640 ms, the delay will not exceed 33.28 µs.

[0383] Example 15

[0384] The concept of the present invention can also be applied to the transmission of timing advance rate of change (TA rate) reference points, Doppler pre-compensation reference points / Doppler post-compensation reference points.

[0385] Specifically, TA rate reference points can be divided into service link TA rate reference points and feeder link TA rate reference points. The service link TA rate mentioned here and thereafter refers to the common service link TA rate.

[0386] Service Link Timing Advance Change Rate (TA rate) Reference Point: The terminal can calculate the service link common timing advance change rate of a beam or cell based on the relative velocity or distance change rate between the satellite (the terminal can obtain the satellite's position and velocity information through ephemeris information) and the service link TA rate reference point. For example, based on the satellite's direction of motion, its position, and the reference point's position, the terminal can calculate the relative velocity V between the satellite and the reference point (V is negative when the satellite and reference point are moving towards each other; V is positive when they are moving in opposite directions). The TA rate equals 2. V / c, where c is the speed of light. 10 8 m / s. This allows us to calculate the change in TA over a period of time ΔT based on the TA rate. 2 V / c. The corrected TA is TA_original + △T 2 V / c, TA_original is the TA used previously. Therefore, the terminal can use this common timing advance change rate to correct the timing advance of the signal sent by the transmitting terminal (if there is a common timing advance change rate of the power supply link, the common timing advance change rate of the service link and the common timing advance change rate of the power supply link can be used together, i.e., the sum of the two, to calculate the final TA change rate, thereby correcting the uplink timing advance adjustment value).

[0387] Feed link timing advance rate (TA rate) reference point: The terminal can calculate the common timing advance rate of the feed link for the beam or cell based on the relative velocity or distance change rate between the satellite (the terminal can obtain the satellite's position and velocity information through ephemeris information) and the feed link TA rate reference point (similar to the description above). The terminal uses this common timing advance rate to correct the timing advance adjustment value of the signal transmitted by the transmitting terminal (if there is a serving link common timing advance rate, the serving link common timing advance rate and the feed link common timing advance rate can be used together, i.e., the sum of the two, to calculate the final TA rate, thereby correcting the uplink timing advance adjustment value). The feed link timing advance rate reference point can be the location coordinates of the gateway station.

[0388] Doppler pre / post-compensation reference point: The terminal can calculate the Doppler pre / post-compensation value of the beam or cell based on the relative motion velocity between the satellite (the terminal can obtain the satellite's position and velocity information through ephemeris information) and the Doppler pre / post-compensation reference point. This Doppler pre / post-compensation value can represent the Doppler post-compensation value applied by the satellite to the signal received by the terminal within the corresponding beam / cell, and the Doppler pre-compensation value applied by the satellite to the downlink signal transmitted within the corresponding beam / cell. Alternatively, this Doppler pre / post-compensation value can represent the Doppler pre-compensation value required by the terminal when transmitting the signal, and the Doppler post-compensation value applied by the terminal when receiving the downlink signal. The Doppler pre / post-compensation reference point can be selected at any location within the beam / cell coverage area, such as the center point of the beam / cell, as needed by the system.

[0389] If the Doppler value calculated based on the Doppler pre / post-compensation reference point and the satellite position and direction of motion represents the Doppler pre-compensation value performed by the network side on the downlink signal, then a terminal with Global Navigation Satellite System (GNSS) capability can calculate the crystal oscillator frequency offset based on the Doppler pre-compensation value and the downlink signal frequency offset. Simultaneously, a GNSS-enabled terminal can calculate the uplink channel-induced Doppler frequency offset value based on its own position, the satellite's position, and the satellite's direction of motion. Subtracting the satellite-side post-compensation value from this uplink channel Doppler frequency offset value yields the pre-compensation value performed by the GNSS-enabled terminal on the signal transmitted by the terminal.

[0390] In one possible design, see Figure 21A A set of reference points can be defined, including service link reference point coordinates, compensation reference point coordinates, ATG reference point coordinates, service link TA rate reference point coordinates, feeder link TA rate reference point coordinates, and Doppler pre / post-compensation reference point coordinates. In another possible design, see... Figure 21B The network side can send the service link TA rate reference point coordinates, the power supply link TA rate reference point coordinates, and the Doppler pre / post-compensation reference point coordinates separately.

[0391] It should be understood that the multiple reference points mentioned above (such as the service link TA rate reference point, feeder link TA rate reference point coordinates, and Doppler pre / post-compensation reference point) may be the same reference point, or multiple reference points may be located at the same position. For example, if two or three of the service link reference point coordinates, service link TA rate reference point coordinates, and Doppler pre / post-compensation reference point coordinates are the same reference coordinates, then the system only needs to transmit one reference coordinate and agree with the terminal in advance on how to use that reference point. For example, if the service link TA rate reference point coordinates and the service link reference point coordinates are the same reference point, then the system and the terminal agree that when the terminal receives the reference point, it can calculate the service link common timing advance change rate of the beam or cell based on the relative motion velocity or distance change rate between the satellite (the terminal can obtain the satellite's position and velocity information through ephemeris information) and the reference point. The terminal then obtains the service link common timing advance adjustment value based on the round-trip time delay between the satellite's position and the reference point.

[0392] The aforementioned reference point group can use the signaling transmission locations used in the foregoing embodiments.

[0393] In one possible implementation, the service link TA rate reference point coordinates, the feeder link TA rate reference point coordinates, and the Doppler pre / post-compensation reference point coordinates can be replaced by service link TA rate values ​​(with positive / negative indications), feeder link TA rate values ​​(with positive / negative indications), and Doppler pre / post-compensation values ​​(with positive / negative indications), respectively. Similar to Embodiment 3, the reference point coordinates and TA rate values, and Doppler pre / post-compensation values ​​can be used in combination. For example... Figure 22 As shown, the service link TA rate reference point coordinates can be used in combination with the feeder link TA rate value and the Doppler pre / post compensation value.

[0394] Another possible implementation, such as Figure 23 As shown, each signaling instruction can be supplemented with an indicator bit to indicate whether the transmitted signaling is the coordinates of the serving link TA rate reference point or the serving link TA rate value (with a positive or negative sign), the coordinates of the feeder link TA rate reference point or the feeder link TA rate value (with a positive or negative sign), or the coordinates of the Doppler pre / post-compensation reference point or the Doppler pre / post-compensation value. For non-staring mode, the common TA rate of the serving link for a certain beam / cell does not change. Therefore, sending signaling to the terminal using the serving link TA rate value (with a positive or negative sign) can reduce the frequency of signaling changes and reduce system complexity. Therefore, as Figure 23 The flexible signaling transmission method shown can reduce the complexity of the system sending signaling.

[0395] When the network side does not send TA rate reference point coordinates or Doppler compensation reference point coordinates to the terminal, or sends invalid coordinate points (such as coordinate values ​​of all zeros), the terminal can use the default reference point coordinate values, such as the coordinate values ​​of the gateway station. That is, when the network side does not send TA rate reference point coordinates or Doppler compensation reference point coordinates to the terminal, or sends invalid coordinate points (such as coordinate values ​​of all zeros), the TA rate reference point coordinates or Doppler compensation reference points revert to the default reference points.

[0396] Example 16

[0397] This embodiment is based on embodiment 14, but replaces the service link / feeder link TA rate reference point coordinates and / or service link / feeder link TA rate values ​​with the service link / feeder link TA rate angles.

[0398] See Figure 24 Assuming the network side will consider the TA rate of the service link from the perspective of... and / or the TA rate angle of the feeder link The satellite's velocity along its direction of motion is A, which is sent to the terminal. Once the terminal receives the TA rate angle, it can use the formula [-2]... cos( ) A / c] calculates the corresponding TA rate value for the service link, according to the formula [-2 cos( ) [A / c] Calculate the corresponding TA rate value of the feeder link. Then, based on the TA rate, the change in TA after a period of time ΔT can be calculated as [-2]. cos( ) A / c]+ [-2 cos( ) A / c]. The corrected TA is TA_original+[-2] cos( ) A / c]+[-2 cos( ) [A / c], TA_original is the TA used previously. If the network side only sends the TArate angle to the terminal service link... or the TA rate angle of the power supply link Then the terminal only needs to calculate TA_original+[-2] cos( ) A / c] or TA_original+[-2 cos( ) The updated TA can be calculated using A / c.

[0399] Example 17

[0400] In this embodiment, the parameters sent to the terminal, such as link reference point coordinates, compensation reference point coordinates, and TA rate reference point coordinates, can all have their corresponding validity periods sent to the terminal simultaneously. This is because LEO satellites are constantly moving, and the positional relationship between the terminal and the satellites is constantly changing. The common timing advance values ​​or reference point coordinates sent by the network to the terminal have a validity period, and are no longer applicable after the validity period expires.

[0401] For example, when the network sends the compensation reference point coordinates to the terminal, it also sends the validity period of these coordinates as ΔT. ΔT can be a value in time slots or in Ts. If it's in time slots, then the terminal will receive the reference point coordinates after ΔT / 2... μ The compensation reference point becomes inapplicable after ms. If in Ts units, then the terminal will receive the coordinates of this reference point after ΔT. The compensation reference point will no longer be applicable after Ts seconds.

[0402] If the network sends link reference point coordinates, compensation reference point coordinates, and TA rate reference point coordinates to the terminal via periodic broadcast, the terminal can obtain new parameter values ​​by re-receiving and decoding the parameters when they expire. If the network sends these coordinates via aperiodic broadcast, the terminal can obtain new parameter values ​​by requesting them from the network when they expire.

[0403] In this embodiment, the parameters sent from the network side to the terminal are configured with a corresponding validity period, which can further improve the reliability of communication.

[0404] It should be noted that, in this embodiment, satellite communication scenarios and ATG communication scenarios can coexist. If both satellite communication scenarios and ATG communication scenarios exist, the network side and the terminal can simultaneously execute the operations performed by the network side and the terminal in the aforementioned ATG communication scenarios. The specific implementation methods in this case can be referred to separately for satellite communication scenarios and ATG communication scenarios, and will not be repeated here.

[0405] The above embodiments can be combined with each other to achieve different technical effects.

[0406] The methods provided in the embodiments of this application above are described from the perspective of interaction between network devices (such as satellites, gateway stations, ATG network devices, etc.) and terminals. To implement the functions of the methods provided in the embodiments of this application above, the terminal and network device may include hardware structures and / or software modules, implementing the above functions in the form of hardware structures, software modules, or a combination of hardware structures and software modules. Whether a particular function is executed in the form of hardware structures, software modules, or a combination of hardware structures and software modules depends on the specific application and design constraints of the technical solution. The communication apparatus of the embodiments of this application is described below.

[0407] This application embodiment also provides a communication device 2500. The device 2500 may be a first network device in the above method embodiments, or a device within the first network device (e.g., a chip, a chip system, or a circuit), or a device compatible with the first network device. The device 2500 may include modules corresponding to the methods / operations / steps / actions performed by the first network device in the method embodiments. These modules may be hardware circuits, software, or a combination of hardware circuits and software implementation.

[0408] For example, see Figure 25 The device 2500 includes: Processing unit 2501 is configured to determine a first parameter based on a first delay compensation value, wherein the first delay compensation value is the delay compensation made by the first network device for the signal sent by the receiving terminal, and the first parameter is configured to indicate the difference between the round-trip delay of the feeder link in the non-terrestrial network NTN and the first delay compensation value, and the difference is configured to determine the TA used by the terminal to send the signal; The sending unit 2502 is used to send the first parameter.

[0409] The specific implementation of the operations performed by each of the above units can be referred to the specific implementation of the operations performed by the first network device in the above method embodiment, and will not be repeated here.

[0410] This application embodiment also provides a communication device 2600, which may be a second network device in the above method embodiments, or a device in the second network device (e.g., a chip, a chip system, or a circuit), or a device that can be used in conjunction with the first network device. The device 2500 may include modules corresponding to the methods / operations / steps / actions performed by the second network device in the method embodiments. These modules may be hardware circuits, software, or a combination of hardware circuits and software implementation.

[0411] For example, see Figure 26The device 2600 includes: Processing unit 2601 is used to determine the position coordinates of the compensation reference point according to the second delay compensation value, wherein the second delay compensation value is the delay compensation value made by the second network device for the signal sent by the receiving terminal; wherein the second delay compensation value is used to determine the TA used by the terminal to send the signal, and the TA is equal to the round-trip delay of the service link in the NTN minus the second delay compensation value; The transmitting unit 2602 is used to transmit the position coordinates of the compensation reference point.

[0412] The specific implementation of the operations performed by each of the above units can be referred to the specific implementation of the operations performed by the second network device in the above method embodiment, and will not be repeated here.

[0413] This application embodiment also provides a communication device 2700, which may be the ATG network device in the above method embodiments, or a device (e.g., a chip, chip system, or circuit) in the ATG network device, or a device that can be used in conjunction with the ATG network device. The device 2700 may include modules corresponding to the methods / operations / steps / actions performed by the ATG network device in the method embodiments. These modules may be hardware circuits, software, or a combination of hardware circuits and software.

[0414] For example, see Figure 27 The device 2700 includes: Processing unit 2701 is used to determine the position coordinates of an ATG reference point, wherein the position coordinates of the ATG reference point are used to determine the TA used by the terminal to send signals to the ATG network device; The transmitting unit 2702 is used to transmit the position coordinates of the ATG reference point.

[0415] The specific implementation of the operations performed by each of the above units can be referred to the specific implementation of the operations performed by the ATG network device in the above method embodiment, and will not be repeated here.

[0416] This application embodiment also provides a communication device 2800. This device 280 can be a terminal as described in the above method embodiments, or a terminal (e.g., a chip, chip system, or circuit) in the ATG network device, or a device compatible with the terminal. The device 2800 can include modules corresponding to the methods / operations / steps / actions performed by the terminal in the method embodiments. These modules can be hardware circuits, software, or a combination of hardware circuits and software.

[0417] For example, see Figure 28The device 2800 includes: The receiving unit 2801 is configured to receive a first parameter, wherein the first parameter is used to indicate the difference between the round-trip time of the feeder link in the non-terrestrial network NTN and a first delay compensation value, the first delay compensation value being the delay compensation made by the first network device for the signal sent by the receiving terminal, and the difference is used to determine the TA used by the terminal to send the signal. Processing unit 2802 is used to determine the TA value used for transmitting the signal based on the first parameter.

[0418] or, The receiving unit 2801 is used to receive the position coordinates of the compensation reference point, wherein the second delay compensation value is the delay compensation value made by the second network device for the signal sent by the receiving terminal, the second delay compensation value is used to determine the TA used by the terminal to send the signal, and the TA is equal to the round-trip delay of the service link in the NTN minus the second delay compensation value. Processing unit 2802 is used to determine the TA used to transmit the signal based on the position coordinates of the compensation reference point.

[0419] or, Receiver unit 2801 is used to receive the position coordinates of the air-to-ground ATG reference point; Processing unit 2802 is used to determine the TA used to transmit the signal based on the position coordinates of the ATG reference point.

[0420] The specific implementation of the operations performed by each of the above units can be referred to the specific implementation of the operations performed by the terminal in the above method embodiments, which will not be repeated here.

[0421] The communication device described above in the embodiments of this application is now described. The following describes possible product forms of the communication device. It should be understood that any device possessing the above-described features... Figures 25-28 Any form of the communication device described herein falls within the protection scope of the embodiments of this application. It should also be understood that the following description is merely illustrative and does not limit the form of the communication device in the embodiments of this application to this specific example.

[0422] Figure 29 This application provides a communication device 2900 that can be used to execute the methods performed by the first network device, second network device, ATG device, or terminal described above. The device 2900 may include a processor 2901 and a communication interface, the communication interface being used to communicate with other communication devices; the processor 2901 is used to run a set of programs to enable the device to implement the method steps described in the method embodiments.

[0423] The processor 2901 can be a general-purpose processor, digital signal processor, application-specific integrated circuit, field-programmable gate array, or other programmable logic device, discrete gate or transistor logic device, or discrete hardware component, and can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor 2901 can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly manifested as being executed by a hardware processor, or being executed by a combination of hardware and software modules in the processor.

[0424] Communication interface 2902 can be a transceiver, circuit, bus, module, or other type of communication interface for communicating with other devices via a transmission medium. For example, when the device is a terminal, the other device can be a satellite, gateway station, or ATG network device. When the device is a satellite, gateway station, or ATG network device, the other device can be a terminal.

[0425] Optionally, the device 2900 may further include a memory 2903 for storing program instructions and / or data. The memory 2903 may be non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), or it may be volatile memory, such as random-access memory (RAM). Memory is any other medium capable of carrying or storing desired program code in the form of instructions or data structures, and accessible by a computer, but is not limited thereto. The memory in this embodiment may also be a circuit or any other device capable of implementing storage functions for storing program instructions and / or data.

[0426] The memory 2903 may be coupled to the processor 2901. In this embodiment, coupling is an indirect coupling or communication connection between devices, units, or modules, and can be electrical, mechanical, or other forms, used for information exchange between devices, units, or modules. The processor 2901 may operate in conjunction with the memory 2903. The processor 2901 may execute program instructions stored in the memory 2903. At least one of the at least one memory 2903 may be included in the processor 2901.

[0427] It should be understood that the specific connection medium between the communication interface 2902, processor 2901, and memory 2903 is not limited in the embodiments of this application. The embodiments of this application... Figure 29 The memory 2903, communication interface 2902, and processor 2901 are connected via a bus. Figure 29The connections between other components are shown in bold and are for illustrative purposes only, not as limiting information. The bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, Figure 29 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0428] Figure 30 This application provides an embodiment of a device 3000, which can be used to execute the methods performed by the first network device, the second network device, the ATG device, or the terminal described above. The device 3000 can be a communication device or a chip within a communication device. Figure 30 As shown, the device 3000 includes: at least one input interface (Input(s)) 3001, logic circuit 3002, and at least one output interface (Output(s)) 3003.

[0429] Optionally, the logic circuit 3002 described above may be a chip, encoder, encoding circuit or other integrated circuit that can implement the method of this application.

[0430] Since the specific methods and embodiments have been described above, the functions of the input interface 3001, logic circuit 3002 or output interface 3003 can be referred to the relevant parts of the corresponding embodiments, and will not be repeated here.

[0431] This application provides a computer-readable storage medium storing computer-readable instructions. When the computer-readable instructions are executed on a communication device, the communication device performs the methods executed by the first network device, the second network device, the ATG device, or the terminal.

[0432] This application provides a computer program product, including instructions that, when run on a computer, cause the computer to perform the methods executed by the first network device, the second network device, the ATG device, or the terminal.

[0433] This application describes embodiments of methods, apparatus (systems), and computer program products according to embodiments of this application with reference to flowchart illustrations and / or block diagrams. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0434] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., digital versatile discs (DVDs)), or semiconductor media (e.g., solid-state disks (SSDs)).

[0435] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this application without departing from the spirit and scope of this application. Therefore, if these modifications and variations to the embodiments of this application fall within the scope of the claims of this application and their equivalents, this application also intends to include these modifications and variations.

Claims

1. A communication method, characterized in that, include: Receive the coordinates of the air-to-ground ATG reference point; The timing advance TA is determined based on the coordinates of the ATG reference point.

2. The communication method according to claim 1, characterized in that, The distance between the location coordinates of the ATG reference point and the location coordinates of the ATG network device meets a preset range; or, The location coordinates of the ATG reference point are the location coordinates of the ATG network device.

3. The communication method according to claim 1 or 2, characterized in that, Receive ATG communication scenario indication information.

4. The communication method according to any one of claims 1 to 3, characterized in that, The coordinates of the ATG reference point are included in the broadcast message.

5. The communication method according to any one of claims 1 to 4, characterized in that, The step of determining the timing advance TA based on the ATG reference point position coordinates includes: The timing advance (TA) is determined based on the round-trip time (RTT) between the terminal and the ATG network device, wherein the RTT between the terminal and the ATG network device is determined based on the position coordinates of the ATG reference point and the position of the terminal.

6. The communication method according to claim 5, characterized in that, Determining the timing advance (TA) based on the round-trip time delay between the terminal and the ATG network device includes: The timing advance (TA) is determined based on the round-trip time between the terminal and the ATG network device, and at least one of a first value or a second value. The first value is obtained from at least one of the Timing Advance Command (TAC) or the Media Access Control (MAC) Control Element (CE), the second value is obtained from the Radio Resource Control (RRC), or the second value is a value agreed upon by the protocol.

7. The communication method according to claim 6, characterized in that, The timing advance is the round-trip delay between the terminal and the ATG network device, which is the sum of the first value and the second value.

8. The communication method according to claim 6 or 7, characterized in that, Also includes: Receive at least one of the first value or the second value.

9. The communication method according to claim 6 or 7, characterized in that, The value of the second value is related to the duplex mode.

10. A communication method, characterized in that, include: Determine the coordinates of the air-to-ground ATG reference point; Send the ATG reference point position coordinates, which are used to determine the timing advance TA.

11. The communication method according to claim 10, characterized in that, The distance between the location coordinates of the ATG reference point and the location coordinates of the ATG network device meets a preset range; or, The location coordinates of the ATG reference point are the location coordinates of the ATG network device.

12. The communication method according to claim 10 or 11, characterized in that, Receive ATG communication scenario indication information.

13. The communication method according to any one of claims 10 to 12, characterized in that, The coordinates of the ATG reference point are included in the broadcast message.

14. The communication method according to any one of claims 10 to 13, characterized in that, The advance timing (TA) is determined based on the round-trip time (RTT) between the terminal and the ATG network device, which is determined based on the position coordinates of the ATG reference point and the position of the terminal.

15. The communication method according to claim 14, characterized in that, The timing advance TA is determined based on the round-trip time delay between the terminal and the ATG network device, and at least one of a first value or a second value; The first value is determined based on at least one of the Timing Advance Command (TAC) or the Media Access Control (MAC) Control Element (CE), and the second value is determined based on the Radio Resource Control (RRC), or the second value is a value agreed upon by the protocol.

16. The communication method according to claim 15, characterized in that, The timing advance is the round-trip delay between the terminal and the ATG network device, which is the sum of the first value and the second value.

17. The communication method according to claim 15 or 16, characterized in that, Also includes: Send at least one of the first value or the second value.

18. The communication method according to claim 15 or 16, characterized in that, The value of the second value is related to the duplex mode.

19. A communication device, characterized in that, Includes units or modules for performing the method according to any one of claims 1-9.

20. A communication device, characterized in that, Includes units or modules for performing the method according to any one of claims 10-18.

21. A communication device, characterized in that, The device includes a processor coupled to a memory storing a computer program, the processor being configured to run the computer program such that the communication device performs the method according to any one of claims 1-9.

22. A communication device, characterized in that, The device includes a processor coupled to a memory storing a computer program, the processor being configured to run the computer program such that the communication device performs the method according to any one of claims 10-18.

23. A computer-readable storage medium, characterized in that, The computer storage medium stores computer-readable instructions that, when executed on a computer, cause the method described in any one of claims 1-9 to be performed; or cause the method described in any one of claims 10-18 to be performed.

24. A computer program product containing instructions, characterized in that, When it is run on a computer, it causes the method of any one of claims 1-9 to be performed; or causes the method of any one of claims 10-18 to be performed.

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