A method and apparatus for adjusting latency in non-terrestrial networks

Abstract

This invention discloses a method and apparatus for adjusting latency in non-terrestrial networks, belonging to the field of satellite communication technology. The method includes: determining the location of a user equipment (UE) and the location of a base station; calculating the distance between the UE and the base station in the same coordinate system based on the UE's and base station's locations; converting the distance into a latency compensation amount based on the speed of light; and compensating for a specific propagation latency offset of the cell based on the latency compensation amount, sending the compensation result to the UE so that the UE can adjust its latency accordingly. This invention does not strongly depend on the TAR (Time Arrival Rate) reported by the UE and can achieve real-time latency compensation and adjustment based on distance estimation at the base station side.

Description

Technical Field

[0001] This invention relates to the field of satellite communication technology, and in particular to a method and apparatus for adjusting latency in non-terrestrial networks. Background Technology

[0002] NTN (Non-Terrestrial Networks) is a communication network established using equipment such as satellites, high-altitude platforms, or drones to provide 5G services to areas where 5G networks are unavailable. User Equipment (UE) supporting NTN functionality communicates with satellites via a server link. The satellite handles the processing at the gNB base station, or the satellite acts as a relay to transmit signals back to the ground-based gNB base station for processing.

[0003] Due to the physical limitation of the speed of light, signal transmission in the air will experience propagation delay. The UE reports a Timing Advance Report (TAR) to help the base station accurately measure the RTT (Round Trip Time) from the UE to the base station, so that the base station can perform accurate uplink scheduling.

[0004] However, in related technologies, the base station is highly dependent on whether the UE reports TAR, and cannot guarantee real-time compensation for latency. Summary of the Invention

[0005] This invention provides a method and apparatus for adjusting latency in non-terrestrial networks, which can solve the problem in related technologies where the strong dependence on whether the UE reports TAR (Time Adaptive Reporting) results in a failure to guarantee real-time latency compensation. The technical solution is as follows: On the one hand, a method for adjusting latency in non-terrestrial networks is provided, the method comprising: Determine the location of the user equipment and the location of the base station itself; Based on the location of the user equipment and the location of the base station, calculate the distance between the user equipment and the base station in the same coordinate system; The distance is converted into a delay compensation amount based on the speed of light, and the specific propagation delay offset of the cell is compensated based on the delay compensation amount. The compensation result is then sent to the user equipment, so that the user equipment can adjust the delay according to the compensation result.

[0006] On the other hand, a non-terrestrial network latency adjustment device is provided, the device comprising: The determining unit is used to determine the location of the user equipment and the location of the base station itself. The calculation unit is used to calculate the distance between the user equipment and the base station in the same coordinate system based on the location of the user equipment and the location of the base station. The compensation unit is used to convert the distance into a delay compensation amount based on the speed of light, and to compensate for the specific propagation delay offset of the cell based on the delay compensation amount, so as to send the compensation result to the user equipment, so that the user equipment can adjust the delay according to the compensation result.

[0007] On the other hand, a computer device is provided, the computer device including a memory and a processor, the memory for storing computer programs, and the processor for executing the computer programs stored in the memory to implement the steps of the non-terrestrial network latency adjustment method described above.

[0008] On the other hand, a computer-readable storage medium is provided, wherein a computer program is stored therein, and when the computer program is executed by a processor, it implements the steps of the above-described non-terrestrial network latency adjustment method.

[0009] On the other hand, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps of the non-terrestrial network latency adjustment method described above.

[0010] The technical solution provided by this invention can bring at least the following beneficial effects: At the base station side, delay adjustment can be proactively performed. This involves determining the location of the user equipment (UAE) and the base station itself, calculating the distance between the UAE and the base station in the same coordinate system based on these two locations, converting the distance into a delay compensation amount, and then using this compensation amount to compensate for specific propagation delay offsets within the cell. Therefore, this scheme is not strongly dependent on the TAR (Time Arrival / Realization) reported by the UAE, and real-time delay compensation and adjustment can be achieved at the base station side based on distance estimation. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a flowchart of a non-terrestrial network latency adjustment method provided by an embodiment of the present invention; Figure 2 This is a structural diagram of a non-terrestrial network latency adjustment device provided in an embodiment of the present invention; Figure 3 This is a hardware architecture diagram of a computer device provided in an embodiment of the present invention. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0014] In 3GPP Release 17, the UE calculates the TAR based on the Cell-Specific Propagation Delay Offset (CellSpecificKoffset) and reports the TAR to the gNB via a UL MAC CE message. The gNB then calculates the compensation result K_ue_offset based on the CellSpecificKoffset and the TAR, and sends the compensation result to the UE via a MAC CE Differential Koffset message. It is evident that the base station's delay adjustment is highly dependent on whether the UE reports the TAR.

[0015] The inventive concept of this invention is that, regardless of whether the UE reports TAR, especially when the UE does not report TAR, the base station can still achieve delay compensation adjustment. Specifically, it can determine the location of the user equipment and the location of the base station itself, and then calculate the distance between the two locations to calculate the delay compensation amount using the distance, thereby compensating for the specific propagation delay offset of the cell.

[0016] The following describes the specific implementation of the above concept.

[0017] Please refer to Figure 1 The present invention provides a method for adjusting latency in non-terrestrial networks, the method comprising: Step 100: Determine the location of the user equipment and the location of the base station itself; Step 102: Calculate the distance between the user equipment and the base station in the same coordinate system based on the location of the user equipment and the location of the base station. Step 104: Convert the distance into a delay compensation amount based on the speed of light, and compensate for the specific propagation delay offset of the cell based on the delay compensation amount, so as to send the compensation result to the user equipment, so that the user equipment can adjust the delay according to the compensation result.

[0018] In this embodiment of the invention, delay adjustment can be actively performed at the base station. This involves determining the location of the user equipment (UAE) and the base station itself, calculating the distance between the UAE and the base station in the same coordinate system based on these two locations, converting the distance into a delay compensation amount, and then using this compensation amount to compensate for specific propagation delay offsets within the cell. Therefore, this solution is not strongly dependent on the TAR (Time Arrival / Realization) reported by the UAE, and real-time delay compensation and adjustment can be achieved at the base station based on distance estimation.

[0019] The following description Figure 1 The execution method of each step is shown.

[0020] First, for step 100, determine the location of the user equipment and the location of the base station itself.

[0021] In this embodiment of the invention, the base station can send an information request to the user equipment on the DCCH (Dedicated Control Channel), the user equipment provides information feedback, and the base station can obtain the location of the user equipment based on the information feedback.

[0022] In one implementation, determining the location of the user equipment includes: Determine whether the user equipment has the capability to report location information; If the device has the capability to report location information, then it is further determined whether the location information reported by the user device is accurate. If the reported location information is accurate, the location of the user equipment is determined using the location information reported by the user equipment. If the reported location information is inaccurate, or if the location information reporting capability is not available, the location of the user equipment shall be determined based on the waveform of the user equipment.

[0023] Specifically, if the base station sends a request to the user equipment but does not receive a response from the user equipment, it indicates that the user equipment does not have the ability to report location information.

[0024] Specifically, when determining whether the location information reported by the user equipment is accurate, it can be determined at least based on single-satellite positioning and Doppler information-assisted positioning.

[0025] If the reported location information is inaccurate, or if the system lacks the capability to report location information, the location of the user equipment (UE) is determined based on the wavelength of the wavelength in which the UE is located. In one implementation, any position within the wavelength of the UE can be used as the UE's location. Preferably, the center of the wavelength of the UE is used as the UE's location.

[0026] In this embodiment of the invention, the location of the base station itself can be obtained from the onboard GNSS receiver.

[0027] Then, for step 102, based on the location of the user equipment and the location of the base station, the distance between the user equipment and the base station in the same coordinate system is calculated.

[0028] To accurately calculate the distance between user equipment and base stations, the locations of the user equipment and base stations need to be transformed to the same coordinate system. This same coordinate system can be a geographic coordinate system, a geocentric coordinate system, a local station-centered coordinate system, a geocentric inertial coordinate system, etc.

[0029] In this embodiment of the invention, taking the geocentric-fixed coordinate system as an example, the distance between the user equipment and the base station in the geocentric-fixed coordinate system can be calculated through the following steps: Step A1: Convert the location of the user equipment to position coordinates in the geocentric coordinate system; Specifically, the location of the user equipment (latitude, longitude, and width) can be determined using the following formula. precision ,high h Convert to position coordinates in the Earth-centered Earth-fixed (ECEF) coordinate system. , , ): Where N is the radius of curvature of the ramusoidal circle, calculated by the following formula: Among them, the WGS84 ellipsoid parameters can be used: semi-long shaft a =6378137.0m Flattening f = 1 / 298.257223563 First eccentricity square e 2 =2f-f 2 ≈0.00669437999014 Step A2: Convert the location of the base station into position coordinates in the geocentric coordinate system.

[0030] In this embodiment of the invention, the location of the satellite base station at UTC (Coordinated Universal Time) time t can be obtained periodically through orbit prediction. : Convert UTC time t to Julian Day JD, then calculate the century number M: Calculation of Greenwich Sidereal Time (GMST) based on century number M: Convert Greenwich Sidereal Time (GMST) to radians : Finally, the location of the base station was converted into position coordinates in the geocentric coordinate system. : A3: Calculate the distance between the user equipment and the base station in the geocentric coordinate system.

[0031] Distance between user equipment and base station It can be calculated using the following formula: in, This refers to the distance between the user equipment and the base station.

[0032] Finally, for step 104, the distance is converted into a delay compensation amount based on the speed of light, and the cell-specific propagation delay offset is compensated based on the delay compensation amount, so that the compensation result is sent to the user equipment, so that the user equipment can adjust the delay according to the compensation result.

[0033] Specifically: The distance can be converted into a time delay compensation amount based on the speed of light. This can be achieved by dividing the distance by the speed of light. That is: in, The value is the time delay compensation, and c is the speed of light, which is 299,792,458 m / s.

[0034] In this embodiment of the invention, the compensation for a specific propagation delay offset of a cell based on the delay compensation amount includes: Determine whether the user equipment has submitted a Timely Advance Report (TAR) and obtain a confirmation result; Based on the determined results and the aforementioned delay compensation amount, compensation is made for the specific propagation delay offset of the cell.

[0035] In one implementation, the compensation for a specific propagation delay offset of a cell based on the determined result and the delay compensation amount includes: If the determination result is that the user equipment did not report TAR, then the difference between the cell-specific propagation delay offset and the delay compensation amount is taken as the compensation result. If the determination result is that the user equipment has reported a TAR, then the specific propagation delay offset of the cell is compensated according to the reported TAR and the delay compensation amount.

[0036] In this embodiment of the invention, the compensation for a specific propagation delay offset of a cell based on the reported TAR and the delay compensation amount can include the following two methods: Method 1: Use the reported TAR or delay compensation amount to compensate for the specific propagation delay offset of the cell.

[0037] In this method one, since the user equipment reports TAR, there are two options. One option is to calculate the coarse compensation amount based on existing technology using TAR and CellSpecificKoffse (cell-specific propagation delay offset), and then use the coarse compensation amount to compensate for the cell-specific propagation delay offset. The other option is to use the delay compensation amount to compensate for the cell-specific propagation delay offset.

[0038] When using delay compensation to compensate for a specific propagation delay offset in a cell, the compensation can be achieved using the following formula: in, To compensate for the outcome, This is the specific propagation delay offset for the cell. This is the amount of time delay compensation.

[0039] Method 2: Integration and Compensation; In this embodiment of the invention, the fusion compensation method may specifically include: calculating a coarse compensation amount based on TAR; fusing the coarse compensation amount and the delay compensation amount to obtain a fusion compensation amount; and using the difference between the cell-specific propagation delay offset and the fusion compensation amount as the compensation result.

[0040] In one implementation, the fusion method can be weighted fusion.

[0041] After obtaining the compensation result, it can be sent to the user equipment so that the user equipment can adjust the latency based on the compensation result.

[0042] It is understandable that after obtaining the compensation result, the base station uses the compensation result to adjust the time delay, and then receives the uplink signal based on the adjusted time delay.

[0043] In this embodiment of the invention, the base station can proactively adjust the latency in scenarios where the user equipment does not report TAR.

[0044] Please refer to Figure 2 This invention provides a non-terrestrial network latency adjustment device, which includes: The determining unit 200 is used to determine the location of the user equipment and the location of the base station itself. The calculation unit 202 is used to calculate the distance between the user equipment and the base station in the same coordinate system based on the location of the user equipment and the location of the base station. The compensation unit 204 is used to convert the distance into a delay compensation amount based on the speed of light, and to compensate for the specific propagation delay offset of the cell based on the delay compensation amount, so as to send the compensation result to the user equipment, so that the user equipment can adjust the delay according to the compensation result.

[0045] In one embodiment of the present invention, determining the location of a user equipment includes: determining whether the user equipment has the capability to report location information; if it has the capability to report location information, further determining whether the location information reported by the user equipment is accurate; if the reported location information is accurate, determining the location of the user equipment using the location information reported by the user equipment; if the reported location information is inaccurate, or if it does not have the capability to report location information, determining the location of the user equipment based on the wavelength of the user equipment.

[0046] In one embodiment of the present invention, determining the location of the user equipment based on the wavelength of the user equipment includes: taking the wavelength center of the wavelength of the user equipment as the location of the user equipment.

[0047] In one embodiment of the present invention, the compensation for a specific propagation delay offset of a cell based on the delay compensation amount includes: determining whether the user equipment reports a Timely Advance Report (TAR) and obtaining a determination result; and compensating for the specific propagation delay offset of the cell based on the determination result and the delay compensation amount.

[0048] In one embodiment of the present invention, the compensation for cell-specific propagation delay offset based on the determination result and the delay compensation amount includes: when the determination result is that the user equipment has not reported TAR, the difference between the cell-specific propagation delay offset and the delay compensation amount is used as the compensation result; when the determination result is that the user equipment has reported TAR, the cell-specific propagation delay offset is compensated according to the reported TAR and the delay compensation amount.

[0049] In one embodiment of the present invention, the step of compensating for a cell-specific propagation delay offset based on the reported TAR and the delay compensation amount includes: calculating a coarse compensation amount based on the TAR; fusing the coarse compensation amount and the delay compensation amount to obtain a fused compensation amount; and using the difference between the cell-specific propagation delay offset and the fused compensation amount as the compensation result.

[0050] It should be noted that the non-terrestrial network latency adjustment device provided in the above embodiments is only an example of the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the non-terrestrial network latency adjustment device and the non-terrestrial network latency adjustment method embodiments provided in the above embodiments belong to the same concept, and their specific implementation process can be found in the method embodiments, which will not be repeated here.

[0051] Embodiments of this application also provide a computer device, please refer to... Figure 3 The computer device includes a processor and a memory, the memory storing at least one instruction, at least one program, code set, or instruction set, the at least one instruction, at least one program, code set, or instruction set being loaded and executed by the processor to implement the non-terrestrial network latency adjustment method provided in the above-described method embodiments.

[0052] Embodiments of this application also provide a computer-readable storage medium storing at least one instruction, at least one program, code set, or instruction set, wherein the at least one instruction, at least one program, code set, or instruction set is loaded and executed by a processor to implement the non-terrestrial network latency adjustment method provided in the above-described method embodiments.

[0053] Embodiments of this application also provide a computer program product, which includes a computer program. A processor of a computer device reads the computer program from a computer-readable storage medium and executes the computer program, causing the computer device to perform any of the non-terrestrial network latency adjustment methods described in the above embodiments.

[0054] For ease of description, the above systems or devices are described separately as various modules or units based on their functions. Of course, in implementing this application, the functions of each unit can be implemented in one or more software and / or hardware components.

[0055] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of this application.

[0056] Finally, it should be noted that in this document, relational terms such as first, second, third, and fourth are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0057] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A method for adjusting latency in non-terrestrial networks, characterized in that, Applied to a base station, the method includes: Determine the location of the user equipment and the location of the base station itself; Based on the location of the user equipment and the location of the base station, calculate the distance between the user equipment and the base station in the same coordinate system; The distance is converted into a delay compensation amount based on the speed of light, and the specific propagation delay offset of the cell is compensated based on the delay compensation amount. The compensation result is then sent to the user equipment, so that the user equipment can adjust the delay according to the compensation result.

2. The method according to claim 1, characterized in that, Determining the location of the user equipment includes: Determine whether the user equipment has the capability to report location information; If the device has the capability to report location information, then it is further determined whether the location information reported by the user device is accurate. If the reported location information is accurate, the location of the user equipment is determined using the location information reported by the user equipment. If the reported location information is inaccurate, or if the location information reporting capability is not available, the location of the user equipment shall be determined based on the waveform of the user equipment.

3. The method according to claim 2, characterized in that... Determining the location of the user equipment based on the wave position of the user equipment includes: The position of the user equipment is defined as the center of the wavelength at which it is located.

4. The method according to claim 1, characterized in that, The compensation for a specific propagation delay offset in a cell based on the aforementioned delay compensation amount includes: Determine whether the user equipment has submitted a Timely Advance Report (TAR) and obtain a confirmation result; Based on the determined results and the aforementioned delay compensation amount, compensation is made for the specific propagation delay offset of the cell.

5. The method according to claim 4, characterized in that, The compensation for a specific propagation delay offset in a cell based on the determined result and the delay compensation amount includes: If the determination result is that the user equipment did not report TAR, then the difference between the cell-specific propagation delay offset and the delay compensation amount is taken as the compensation result. If the determination result is that the user equipment has reported a TAR, then the specific propagation delay offset of the cell is compensated according to the reported TAR and the delay compensation amount.

6. The method according to claim 5, characterized in that, The compensation for a specific propagation delay offset in the cell based on the reported TAR and the delay compensation amount includes: Coarse compensation amount is calculated based on TAR; The coarse compensation amount and the time delay compensation amount are fused to obtain the fused compensation amount; The difference between the cell-specific propagation delay offset and the fusion compensation amount is used as the compensation result.

7. A non-terrestrial network delay adjustment device, characterized in that, The device includes: The determining unit is used to determine the location of the user equipment and the location of the base station itself. The calculation unit is used to calculate the distance between the user equipment and the base station in the same coordinate system based on the location of the user equipment and the location of the base station. The compensation unit is used to convert the distance into a delay compensation amount based on the speed of light, and to compensate for the specific propagation delay offset of the cell based on the delay compensation amount, so as to send the compensation result to the user equipment, so that the user equipment can adjust the delay according to the compensation result.

8. A computer device, characterized in that, The computer device includes a memory and a processor. The memory is used to store computer programs, and the processor is used to execute the computer programs stored in the memory to implement the steps of the method according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, implements the steps of the method described in any one of claims 1-6.

10. A computer program product, characterized in that, Includes a computer program, which, when executed by a processor, implements the steps of the method according to any one of claims 1-6.

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