A method and device for synchronizing low-orbit satellite data frames

Abstract

The present invention discloses a low-orbit satellite data frame synchronization method and device, which first receives synchronization information sent by the low-orbit satellite, then obtains compensation parameters based on the synchronization information, and finally completes uplink data frame synchronization and downlink data frame synchronization between the low-orbit satellite and the ground terminal based on the compensation parameters, thereby improving communication efficiency and ensuring synchronous communication of broadband data between the low-orbit satellite and the ground terminal.

Description

Technical Field

[0001] The present invention relates to the field of wireless communications, and in particular to a low-orbit satellite data frame synchronization method and device. Background Art

[0002] Satellites are primarily categorized by their orbital altitude: low-orbit, medium-orbit, and high-orbit. Compared to traditional high-orbit and medium-orbit satellites, low-orbit satellites offer advantages such as high data bandwidth, low transmission latency, low link loss, and low manufacturing costs. Therefore, low-orbit satellite communications are the preferred solution for satellite internet.

[0003] Low-orbit satellite communications can be used for distance education and telemedicine services in remote mountainous areas. They can also provide secure and controllable communications in key areas such as the deep ocean and the North and South Poles. They are suitable for polar regions, travel, deserts, and ocean communications, meeting the data connection requirements of users from various industries and ordinary users in various special environments. However, existing technologies may not synchronize communications between low-orbit satellites and ground terminals, resulting in low communication efficiency. Summary of the Invention

[0004] The technical problem to be solved by the present invention is communication asynchrony. The purpose is to provide a low-orbit satellite data frame synchronization method and device, which solves the problem of communication asynchrony between low-orbit satellites and ground terminals.

[0005] The present invention is achieved through the following technical solutions:

[0006] In a first aspect, the present invention provides a low-orbit satellite data frame synchronization method, comprising:

[0007] Acquiring synchronization information sent by a low-orbit satellite, wherein the synchronization information includes operating parameters of the low-orbit satellite;

[0008] Determining compensation parameters according to the operating parameters of the low-orbit satellite;

[0009] According to the compensation parameters, the downlink data frame and the uplink data frame are synchronized to complete the synchronization of the low-orbit satellite data frame. The uplink data frame represents the data frame sent to the low-orbit satellite, and the downlink data frame represents the data frame received from the low-orbit satellite.

[0010] Furthermore, the operating parameters of the low-orbit satellite include position parameters of the low-orbit satellite and speed parameters of the low-orbit satellite.

[0011] Furthermore, determining compensation parameters according to the operating parameters of the low-orbit satellite includes:

[0012] According to the position parameters of the low-orbit satellite, the time compensation parameters are determined as:

[0013]

[0014] Where ΔT represents the time compensation parameter, Indicates the position of low-orbit satellite s at the current synchronization time, represents the location of ground terminal r at the current synchronization time, l i represents the unit vector from the ground terminal r to the low-orbit satellite at the current synchronization moment, C represents the speed of light, Indicates the position of the low-orbit satellite s at the last synchronization time i-1, represents the position of the ground terminal r at the last synchronization time i-1, l i-1 represents the unit vector from the ground terminal r to the low-orbit satellite at the last synchronization time i-1;

[0015] According to the speed parameter of the low-orbit satellite, the frequency compensation parameter is determined as:

[0016]

[0017] Where ΔF represents the frequency compensation parameter, represents the speed of low-orbit satellite s at the current synchronization moment, represents the speed of ground terminal r at the current synchronization time, represents the speed of the low-orbit satellite s at the last synchronization time i-1, represents the speed of the ground terminal r at the last synchronization time i-1, and f0 represents the reference center frequency of the ground terminal.

[0018] Furthermore, synchronizing the downlink data frame and the uplink data frame according to the compensation parameter includes:

[0019] According to the time compensation parameter ΔT, the time T of the downlink data frame is dl Synchronize;

[0020] According to the frequency compensation parameter ΔF, the frequency F of the downlink data frame is adjusted. dl Synchronize;

[0021] According to the time compensation parameter ΔT, the time T of the uplink data frame is ul Synchronize;

[0022] According to the frequency compensation parameter ΔF, the frequency F of the uplink data frame is adjusted. ul to synchronize.

[0023] Furthermore, according to the time compensation parameter ΔT, the time T of the downlink data frame is dl Synchronize, including:

[0024] A. Obtaining the time compensation threshold ΔT Max, the time compensation threshold ΔT Max It is pre-set data or data generated in response to human-computer interaction;

[0025] B. Determine whether the time compensation parameter ΔT is greater than 0. If so, proceed to step C; otherwise, proceed to step D.

[0026] C. Determine whether the time compensation parameter ΔT is greater than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and obtain the time T of the downlink data frame dl The sum of the local reference time of the ground terminal and the time compensation parameter ΔT, otherwise the time T of the downlink data frame is directly obtained. dl is the sum of the local reference time of the ground terminal and the time compensation parameter ΔT;

[0027] D. Determine whether the time compensation parameter ΔT is less than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and obtain the time T of the downlink data frame dl The sum of the local reference time of the ground terminal and the time compensation parameter ΔT, otherwise the time T of the downlink data frame is directly obtained. dl It is the sum of the local reference time of the ground terminal and the time compensation parameter ΔT.

[0028] Furthermore, according to the frequency compensation parameter ΔF, the frequency F of the downlink data frame is dl Synchronize, including:

[0029] Get the frequency F of the downlink data frame dl It is the sum of the reference center frequency of the ground terminal and the frequency compensation parameter ΔF.

[0030] Furthermore, according to the time compensation parameter ΔT, the time T of the uplink data frame is ul Synchronize, including:

[0031] a. Obtaining the time compensation threshold ΔT Max , the time compensation threshold ΔT Max It is pre-set data or data generated in response to human-computer interaction;

[0032] b. Determine whether the time compensation parameter ΔT is greater than 0. If so, proceed to step c; otherwise, proceed to step d.

[0033] c. Determine whether the time compensation parameter ΔT is greater than the time compensation threshold ΔT MaxIf so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and get the time T of the uplink data frame ul The difference between the local reference time of the ground terminal and the time compensation parameter ΔT is subtracted. Otherwise, the time T of the uplink data frame is directly obtained. ul The difference between the local reference time of the ground terminal and the time compensation parameter ΔT;

[0034] d. Determine whether the time compensation parameter ΔT is less than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and get the time T of the uplink data frame ul The difference between the local reference time of the ground terminal and the time compensation parameter ΔT is subtracted. Otherwise, the time T of the uplink data frame is directly obtained. ul It is the difference between the local reference time of the ground terminal and the time compensation parameter ΔT.

[0035] Furthermore, according to the frequency compensation parameter ΔF, the frequency F of the uplink data frame is ul Synchronize, including:

[0036] Get the frequency F of the uplink data frame ul It is the difference between the reference center frequency of the ground terminal and the frequency compensation parameter ΔF.

[0037] Furthermore, after synchronizing the downlink data frame and the uplink data frame according to the compensation parameter, the method further includes:

[0038] Synchronize the downlink and uplink data frames and monitor in real time whether the synchronization is lost. If so, re-synchronize. Otherwise, continue monitoring until the synchronization is lost and re-synchronize.

[0039] In a second aspect, the present invention provides a low-orbit satellite data frame synchronization device, comprising a synchronization information acquisition module, a compensation parameter determination module, and a synchronization module;

[0040] The synchronization information acquisition module is used to acquire synchronization information sent by the low-orbit satellite, where the synchronization information includes operating parameters of the low-orbit satellite;

[0041] The compensation parameter determination module is used to determine the compensation parameter according to the operating parameters of the low-orbit satellite;

[0042] The synchronization module is used to synchronize the downlink data frame and the uplink data frame according to the compensation parameter to complete the synchronization of the low-orbit satellite data frame. The uplink data frame represents the data frame sent to the low-orbit satellite, and the downlink data frame represents the data frame received from the low-orbit satellite.

[0043] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0044] The present invention provides a low-orbit satellite data frame synchronization method and device, which first receives synchronization information sent by the low-orbit satellite, then obtains compensation parameters based on the synchronization information, and finally completes uplink data frame synchronization and downlink data frame synchronization between the low-orbit satellite and the ground terminal based on the compensation parameters, thereby improving communication efficiency and ensuring synchronous communication of broadband data between the low-orbit satellite and the ground terminal. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those skilled in the art, other relevant drawings can be obtained based on these drawings without creative work.

[0046] In the picture:

[0047] Figure 1 A flowchart of a low-orbit satellite data frame synchronization method provided by an embodiment of the present invention.

[0048] Figure 2 A schematic diagram of the structure of a synchronization frame provided in an embodiment of the present invention.

[0049] Figure 3 A schematic structural diagram of a low-orbit satellite data frame synchronization device provided by an embodiment of the present invention.

[0050] Figure 4 A schematic structural diagram of a low-orbit satellite data frame synchronization device provided by an embodiment of the present invention.

[0051] Markings and corresponding parts names in the accompanying drawings:

[0052] 21 - synchronization information acquisition module, 22 - compensation parameter determination module, 23 - synchronization module, 31 - memory, 32 - processor, 33 - bus. DETAILED DESCRIPTION

[0053] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with examples and drawings. The exemplary embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0054] Example 1

[0055] like Figure 1As shown, a low-orbit satellite data frame synchronization method includes:

[0056] S11. Acquire synchronization information sent by the low-orbit satellite, where the synchronization information includes operating parameters of the low-orbit satellite.

[0057] Optionally, you can obtain synchronization information sent by low-orbit satellites in the following ways:

[0058] The synchronization frame data is received by the radio frequency front end of the ground terminal and demodulated to obtain the synchronization information contained in the synchronization frame.

[0059] like Figure 2 As shown, this embodiment provides a synchronization frame structure, each synchronization frame is a superframe, each superframe includes N subframes, each subframe includes P radio frames, and the subframe also includes a synchronization frame time slot. The synchronization frame time slot uses a fixed bit (byte) FID (field identifier) ​​as the starting field for synchronization frame marking, followed by other synchronization fields, which include TS time scale, satellite status and calibration information INFO, MASK mask and CRC (Cyclic Redundancy Check).

[0060] S12. Determine compensation parameters based on the operating parameters of the low-orbit satellite.

[0061] The compensation parameters may include a time compensation parameter corresponding to the local reference time of the ground terminal and a frequency compensation parameter corresponding to the reference center frequency of the ground terminal.

[0062] S13. Synchronize the downlink data frame and the uplink data frame according to the compensation parameter to complete the synchronization of the low-orbit satellite data frame. The uplink data frame represents the data frame sent to the low-orbit satellite, and the downlink data frame represents the data frame received from the low-orbit satellite.

[0063] The local reference time in the downlink and uplink data frames can be compensated according to the time compensation parameter. The reference center frequency in the downlink and uplink data frames can be compensated according to the frequency compensation parameter, thereby achieving synchronization of the downlink and uplink data frames.

[0064] Optionally, each time a downlink data frame sent by a low-orbit satellite is received, synchronization is performed, thereby achieving automatic synchronization.

[0065] The execution subject of this implementation method can be a low-orbit satellite data frame synchronization device, which can be implemented by software or by a combination of software and hardware.

[0066] In a possible implementation, the operating parameters of the low-orbit satellite include a position parameter of the low-orbit satellite and a speed parameter of the low-orbit satellite.

[0067] In this embodiment, each time a data frame is sent to a low-orbit satellite, a unit vector from the ground terminal to the low-orbit satellite may be sent to the low-orbit satellite.

[0068] Optionally, the synchronization information may further include a unit vector corresponding to the current synchronization time and a unit vector corresponding to the previous synchronization time. The compensation parameter may be determined based on the operating parameters of the low-orbit satellite and the unit vector.

[0069] In one possible implementation, determining the compensation parameters based on the operating parameters of the low-orbit satellite includes:

[0070] According to the position parameters of the low-orbit satellite, the time compensation parameters are determined as:

[0071]

[0072] Where ΔT represents the time compensation parameter, Indicates the position of low-orbit satellite s at the current synchronization time, represents the location of ground terminal r at the current synchronization time, l i represents the unit vector from the ground terminal r to the low-orbit satellite at the current synchronization moment, C represents the speed of light, Indicates the position of the low-orbit satellite s at the last synchronization time i-1, represents the position of the ground terminal r at the last synchronization time i-1, l i-1 Represents the unit vector from the ground terminal r to the low-orbit satellite at the last synchronization time i-1.

[0073] According to the speed parameters of the low-orbit satellite, the frequency compensation parameters are determined as:

[0074]

[0075] Where ΔF represents the frequency compensation parameter, represents the speed of low-orbit satellite s at the current synchronization moment, represents the speed of ground terminal r at the current synchronization time, represents the speed of the low-orbit satellite s at the last synchronization time i-1, represents the speed of the ground terminal r at the last synchronization time i-1, and f0 represents the reference center frequency of the ground terminal.

[0076] In a possible implementation, synchronizing downlink data frames and uplink data frames according to the compensation parameter includes:

[0077] According to the time compensation parameter ΔT, the time T of the downlink data framedl Synchronize;

[0078] According to the frequency compensation parameter ΔF, the frequency F of the downlink data frame is adjusted. dl Synchronize;

[0079] According to the time compensation parameter ΔT, the time T of the uplink data frame is ul Synchronize;

[0080] According to the frequency compensation parameter ΔF, the frequency F of the uplink data frame is adjusted. ul to synchronize.

[0081] In a possible implementation manner, the time T of the downlink data frame is adjusted according to the time compensation parameter ΔT. dl Synchronize, including:

[0082] A. Obtaining the time compensation threshold ΔT Max , time compensation threshold ΔT Max It is pre-set data or data generated in response to human-computer interaction.

[0083] B. Determine whether the time compensation parameter ΔT is greater than 0. If so, proceed to step C; otherwise, proceed to step D.

[0084] C. Determine whether the time compensation parameter ΔT is greater than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and obtain the time T of the downlink data frame dl The sum of the local reference time of the ground terminal and the time compensation parameter ΔT, otherwise the time T of the downlink data frame is directly obtained. dl It is the sum of the local reference time of the ground terminal and the time compensation parameter ΔT.

[0085] D. Determine whether the time compensation parameter ΔT is less than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and obtain the time T of the downlink data frame dl The sum of the local reference time of the ground terminal and the time compensation parameter ΔT, otherwise the time T of the downlink data frame is directly obtained. dl It is the sum of the local reference time of the ground terminal and the time compensation parameter ΔT.

[0086] In a possible implementation manner, the frequency F of the downlink data frame is adjusted according to the frequency compensation parameter ΔF. dl Synchronize, including:

[0087] Get the frequency F of the downlink data frame dlIt is the sum of the reference center frequency of the ground terminal and the frequency compensation parameter ΔF.

[0088] In a possible implementation manner, the time T of the uplink data frame is adjusted according to the time compensation parameter ΔT. ul Synchronize, including:

[0089] a. Obtain time compensation threshold ΔT Max , time compensation threshold ΔT Max It is pre-set data or data generated in response to human-computer interaction;

[0090] b. Determine whether the time compensation parameter ΔT is greater than 0. If so, proceed to step c; otherwise, proceed to step d.

[0091] c. Determine whether the time compensation parameter ΔT is greater than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and get the time T of the uplink data frame ul The difference between the local reference time of the ground terminal and the time compensation parameter ΔT is subtracted. Otherwise, the time T of the uplink data frame is directly obtained. ul The difference between the local reference time of the ground terminal and the time compensation parameter ΔT;

[0092] d. Determine whether the time compensation parameter ΔT is less than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and get the time T of the uplink data frame ul The difference between the local reference time of the ground terminal and the time compensation parameter ΔT is subtracted. Otherwise, the time T of the uplink data frame is directly obtained. ul It is the difference between the local reference time of the ground terminal and the time compensation parameter ΔT.

[0093] In a possible implementation manner, the frequency F of the uplink data frame is adjusted according to the frequency compensation parameter ΔF. ul Synchronize, including:

[0094] Get the frequency F of the uplink data frame ul It is the difference between the reference center frequency of the ground terminal and the frequency compensation parameter ΔF.

[0095] In a possible implementation manner, after synchronizing the downlink data frame and the uplink data frame according to the compensation parameter, the method further includes:

[0096] Synchronize the downlink and uplink data frames and monitor in real time whether the synchronization is lost. If so, re-synchronize. Otherwise, continue monitoring until the synchronization is lost and re-synchronize.

[0097] After detecting that the synchronization lock is lost, the synchronization lock is immediately re-established to ensure the synchronization of the data frame.

[0098] Optionally, a synchronization lock flag may be set to monitor synchronization lock. If the synchronization lock flag fails, the synchronization lock fails and needs to be re-locked.

[0099] The low-orbit satellite data frame synchronization device provided in this embodiment can achieve a frame synchronization frequency within 1 Hz, and can automatically re-lock the frame synchronization after the synchronization is lost.

[0100] Example 2

[0101] like Figure 3 As shown, this embodiment provides a low-orbit satellite data frame synchronization device, including a synchronization information acquisition module 21, a compensation parameter determination module 22 and a synchronization module 23.

[0102] The synchronization information acquisition module 21 is used to acquire synchronization information sent by the low-orbit satellite, where the synchronization information includes operating parameters of the low-orbit satellite.

[0103] The compensation parameter determination module 22 is used to determine the compensation parameters according to the operating parameters of the low-orbit satellite.

[0104] The synchronization module 23 is used to synchronize the downlink data frame and the uplink data frame according to the compensation parameters to complete the synchronization of the low-orbit satellite data frame. The uplink data frame represents the data frame sent to the low-orbit satellite, and the downlink data frame represents the data frame received from the low-orbit satellite.

[0105] The low-orbit satellite data frame synchronization device described in this embodiment can implement the technical solution described in the above-mentioned embodiment 1. Its implementation principle and beneficial effects are similar and will not be repeated here.

[0106] Example 3

[0107] like Figure 4 As shown, this embodiment provides a low-orbit satellite data frame synchronization device, including a memory 31 and a processor 32, and the memory 31 and the processor 32 are interconnected via a bus 33.

[0108] The memory 31 stores computer-executable instructions.

[0109] The processor 32 executes the computer-executable instructions stored in the memory, so that the processor executes a low-orbit satellite data frame synchronization method as described in Example 1.

[0110] For example, the memory may include, but is not limited to, random access memory (RAM), read-only memory (ROM), flash memory, first-in-first-out memory (FIFO), and / or first-in-last-out memory (FILO). Specifically, the processor may include one or more processing cores, such as a quad-core processor or an octa-core processor. The processor may be implemented in at least one hardware form selected from the group consisting of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). Furthermore, the processor may include a main processor and a coprocessor. The main processor is a processor for processing data in an awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in a standby state.

[0111] In some embodiments, the processor may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. For example, the processor may be, but is not limited to, a microprocessor of the STM32F105 series, a reduced instruction set computer (RISC) microprocessor, an X86 architecture processor, or a processor with an integrated embedded neural network processing unit (NPU); the transceiver may be, but is not limited to, a wireless fidelity (WIFI) wireless transceiver, a Bluetooth wireless transceiver, a general packet radio service technology (GPRS) wireless transceiver, a ZigBee protocol (a low-power local area network protocol based on the IEEE802.15.4 standard, ZigBee) wireless transceiver, a 3G transceiver, a 4G transceiver, and / or a 5G transceiver. In addition, the device may also include, but is not limited to, a power module, a display screen, and other necessary components.

[0112] Example 4

[0113] This embodiment provides a computer-readable storage medium, which stores computer-executable instructions. When the computer-executable instructions are executed by a processor, they are used to implement a low-orbit satellite data frame synchronization method as described in Example 1.

[0114] Example 5

[0115] An embodiment of the present application may also provide a computer program product, including a computer program, which, when executed by a processor, implements a low-orbit satellite data frame synchronization method as described in Example 1.

[0116] The above specific implementation methods further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific implementation methods of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A low-orbit satellite data frame synchronization method, characterized in that: include: Acquiring synchronization information sent by a low-orbit satellite, wherein the synchronization information includes operating parameters of the low-orbit satellite; Determining compensation parameters according to the operating parameters of the low-orbit satellite; Synchronizing downlink data frames and uplink data frames according to the compensation parameters to complete synchronization of low-orbit satellite data frames, wherein the uplink data frames represent data frames sent to the low-orbit satellite and the downlink data frames represent data frames received from the low-orbit satellite; The operating parameters of the low-orbit satellite include the position parameters of the low-orbit satellite and the speed parameters of the low-orbit satellite; Determining compensation parameters according to the operating parameters of the low-orbit satellite includes: According to the position parameters of the low-orbit satellite, the time compensation parameters are determined as: Where ΔT represents the time compensation parameter, Indicates the position of low-orbit satellite s at the current synchronization time, represents the location of ground terminal r at the current synchronization time, l i represents the unit vector from the ground terminal r to the low-orbit satellite at the current synchronization moment, C represents the speed of light, Indicates the position of the low-orbit satellite s at the last synchronization time i-1, represents the position of the ground terminal r at the last synchronization time i-1, l i-1 represents the unit vector from the ground terminal r to the low-orbit satellite at the last synchronization time i-1; Synchronizing the downlink data frame and the uplink data frame according to the compensation parameter, including: According to the time compensation parameter ΔT, the time T of the downlink data frame is dl Synchronize; According to the time compensation parameter ΔT, the time T of the downlink data frame is dl Synchronize, including: A. Obtaining the time compensation threshold ΔT Max , the time compensation threshold ΔT Max It is pre-set data or data generated in response to human-computer interaction; B. Determine whether the time compensation parameter ΔT is greater than 0. If so, proceed to step C; otherwise, proceed to step D. C. Determine whether the time compensation parameter ΔT is greater than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and obtain the time T of the downlink data frame dl The sum of the local reference time of the ground terminal and the time compensation parameter ΔT, otherwise the time T of the downlink data frame is directly obtained. dl is the sum of the local reference time of the ground terminal and the time compensation parameter ΔT; D. Determine whether the time compensation parameter ΔT is less than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and obtain the time T of the downlink data frame dl The sum of the local reference time of the ground terminal and the time compensation parameter ΔT, otherwise the time T of the downlink data frame is directly obtained. dl is the sum of the local reference time of the ground terminal and the time compensation parameter ΔT; According to the speed parameter of the low-orbit satellite, the frequency compensation parameter is determined as: Where ΔF represents the frequency compensation parameter, represents the speed of low-orbit satellite s at the current synchronization moment, represents the speed of ground terminal r at the current synchronization time, represents the speed of the low-orbit satellite s at the last synchronization time i-1, represents the speed of the ground terminal r at the last synchronization time i-1, and f0 represents the reference center frequency of the ground terminal; Synchronizing the downlink data frame and the uplink data frame according to the compensation parameter, including: According to the frequency compensation parameter ΔF, the frequency F of the downlink data frame is adjusted. dl Synchronize; According to the time compensation parameter ΔT, the time T of the uplink data frame is ul Synchronize; According to the frequency compensation parameter ΔF, the frequency F of the uplink data frame is adjusted. ul Synchronize; According to the frequency compensation parameter ΔF, the frequency F of the downlink data frame is adjusted. dl Synchronize, including: Get the frequency F of the downlink data frame dl It is the sum of the reference center frequency of the ground terminal and the frequency compensation parameter ΔF.

2. The low-orbit satellite data frame synchronization method according to claim 1, characterized in that: According to the time compensation parameter ΔT, the time T of the uplink data frame is ul Synchronize, including: a. Obtain time compensation threshold ΔT Max , the time compensation threshold ΔT Max It is pre-set data or data generated in response to human-computer interaction; b. Determine whether the time compensation parameter ΔT is greater than 0. If so, proceed to step c; otherwise, proceed to step d. c. Determine whether the time compensation parameter ΔT is greater than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and get the time T of the uplink data frame ul The difference between the local reference time of the ground terminal and the time compensation parameter ΔT is subtracted. Otherwise, the time T of the uplink data frame is directly obtained. ul The difference between the local reference time of the ground terminal and the time compensation parameter ΔT; d. Determine whether the time compensation parameter ΔT is less than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and get the time T of the uplink data frame ul The difference between the local reference time of the ground terminal and the time compensation parameter ΔT is subtracted. Otherwise, the time T of the uplink data frame is directly obtained. ul It is the difference between the local reference time of the ground terminal and the time compensation parameter ΔT.

3. The low-orbit satellite data frame synchronization method according to claim 1, characterized in that: According to the frequency compensation parameter ΔF, the frequency F of the uplink data frame is adjusted. ul Synchronize, including: Get the frequency F of the uplink data frame ul It is the difference between the reference center frequency of the ground terminal and the frequency compensation parameter ΔF.

4. The low-orbit satellite data frame synchronization method according to claim 1, characterized in that: After synchronizing the downlink data frame and the uplink data frame according to the compensation parameter, the method further includes: Synchronize the downlink and uplink data frames and monitor in real time whether the synchronization is lost. If so, re-synchronize. Otherwise, continue monitoring until the synchronization is lost and re-synchronize.

5. A low-orbit satellite data frame synchronization device, characterized in that: It includes a synchronization information acquisition module, a compensation parameter determination module and a synchronization module; The synchronization information acquisition module is used to acquire synchronization information sent by the low-orbit satellite, where the synchronization information includes operating parameters of the low-orbit satellite, and the operating parameters of the low-orbit satellite include position parameters of the low-orbit satellite and speed parameters of the low-orbit satellite; The compensation parameter determination module is used to determine the compensation parameter according to the operating parameters of the low-orbit satellite; Determining compensation parameters according to the operating parameters of the low-orbit satellite includes: According to the position parameters of the low-orbit satellite, the time compensation parameters are determined as: Where ΔT represents the time compensation parameter, Indicates the position of low-orbit satellite s at the current synchronization time, represents the location of ground terminal r at the current synchronization time, l i represents the unit vector from the ground terminal r to the low-orbit satellite at the current synchronization moment, C represents the speed of light, Indicates the position of the low-orbit satellite s at the last synchronization time i-1, represents the position of the ground terminal r at the last synchronization time i-1, l i-1 represents the unit vector from the ground terminal r to the low-orbit satellite at the last synchronization time i-1; Synchronizing the downlink data frame and the uplink data frame according to the compensation parameter, including: According to the time compensation parameter ΔT, the time T of the downlink data frame is dl Synchronize; According to the time compensation parameter ΔT, the time T of the downlink data frame is dl Synchronize, including: A. Obtaining the time compensation threshold ΔT Max , the time compensation threshold ΔT Max It is pre-set data or data generated in response to human-computer interaction; B. Determine whether the time compensation parameter ΔT is greater than 0. If so, proceed to step C; otherwise, proceed to step D. C. Determine whether the time compensation parameter ΔT is greater than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and obtain the time T of the downlink data frame dl The sum of the local reference time of the ground terminal and the time compensation parameter ΔT, otherwise the time T of the downlink data frame is directly obtained. dl is the sum of the local reference time of the ground terminal and the time compensation parameter ΔT; D. Determine whether the time compensation parameter ΔT is less than the time compensation threshold ΔT Max If so, update the value of the time compensation parameter ΔT to the time compensation threshold ΔT Max The value of and obtain the time T of the downlink data frame dl The sum of the local reference time of the ground terminal and the time compensation parameter ΔT, otherwise the time T of the downlink data frame is directly obtained. dl is the sum of the local reference time of the ground terminal and the time compensation parameter ΔT; According to the speed parameter of the low-orbit satellite, the frequency compensation parameter is determined as: Where ΔF represents the frequency compensation parameter, represents the speed of low-orbit satellite s at the current synchronization moment, represents the speed of ground terminal r at the current synchronization time, represents the speed of the low-orbit satellite s at the last synchronization time i-1, represents the speed of the ground terminal r at the last synchronization time i-1, and f0 represents the reference center frequency of the ground terminal; Synchronizing the downlink data frame and the uplink data frame according to the compensation parameter, including: According to the frequency compensation parameter ΔF, the frequency F of the downlink data frame is adjusted. dl Synchronize; According to the time compensation parameter ΔT, the time T of the uplink data frame is ul Synchronize; According to the frequency compensation parameter ΔF, the frequency F of the uplink data frame is adjusted. ul Synchronize; According to the frequency compensation parameter ΔF, the frequency F of the downlink data frame is adjusted. dl Synchronize, including: Get the frequency F of the downlink data frame dl is the sum of the reference center frequency of the ground terminal and the frequency compensation parameter ΔF; The synchronization module is used to synchronize the downlink data frame and the uplink data frame according to the compensation parameter to complete the synchronization of the low-orbit satellite data frame. The uplink data frame represents the data frame sent to the low-orbit satellite, and the downlink data frame represents the data frame received from the low-orbit satellite.

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