A low-orbit satellite communication uplink transmission advance amount comprehensive prediction method, a storage medium and an electronic device

Abstract

This application provides a method, storage medium, and electronic device for comprehensively predicting uplink transmission lead in low-Earth orbit (LEO) satellite communication, relating to the field of LEO satellite communication technology. The method includes: preparing initial parameters; calculating satellite ephemeris and correcting local time based on the initial parameters; continuously comparing local time with the satellite transit start time, calculating the position coordinates of the ground user terminal at each step after the satellite transit start time; synchronously reading ephemeris data and calculating satellite-to-end transmission delay; determining the uplink transmission lead based on the satellite-to-end transmission delay and performing uplink synchronization; after uplink synchronization, the ground user terminal sends ranging frames to the satellite during service idle periods, and the onboard processing payload demodulates the ranging frames to obtain the uplink delay error and feeds it back to the ground user terminal. This method achieves accurate and rapid prediction of uplink transmission lead in LEO satellite communication, facilitating rapid uplink synchronization.

Description

Technical Field

[0001] This application relates to the field of low-Earth orbit satellite communication technology, and more specifically, to a method for comprehensively predicting uplink transmission lead time in low-Earth orbit satellite communication, a storage medium, and an electronic device. Background Technology

[0002] In recent years, with the rise of satellite internet, low-Earth orbit (LEO) satellite communication has regained widespread attention due to its advantages of low latency, large capacity, global coverage, and cost. A significant characteristic of LEO satellite communication is the dynamic transmission delay between ground user terminals (hereinafter referred to as terminals) and satellites due to their relatively high-speed movement. This causes uplink signals from each terminal to not arrive at the satellite in strict accordance with the predetermined sequence. This presents a severe uplink synchronization challenge for LEO satellite communication systems that employ burst-based mechanisms. Furthermore, due to considerations such as universality and reducing processing resource consumption, satellites generally do not handle the impact of dynamic satellite-to-ground delays. Therefore, this problem must be solved by each terminal.

[0003] The key to solving this problem lies in the accurate prediction of dynamic transmission delay between satellites and terminals by each terminal, thereby determining the uplink transmission lead. Considering that the downlink is less affected by dynamic delay and synchronization is relatively easy, one approach is to broadcast satellite position information in the downlink channel. After receiving the satellite position information, the terminal can calculate the satellite-to-terminal transmission delay by combining it with its own position information. The problem is that the satellite position data received by the terminal is already lagging behind the actual satellite position, so this method is not suitable for situations with high delay error requirements. Another approach is a closed-loop delay prediction method based on a "preset-detect-feedback-correction" process. This method requires real-time exchange of delay correction information on dedicated synchronization and signaling channels after initial synchronization, resulting in high resource consumption, implementation complexity, and long processing time. For low-Earth orbit satellite communication systems that frequently undergo satellite switching, the communication time under a single satellite is generally only a few minutes. Excessive uplink delay prediction time will reduce communication QoS and user experience, thus limiting the application of this method in low-Earth orbit satellite communication systems. Summary of the Invention

[0004] This application provides a method for comprehensive prediction of uplink transmission lead time in low-Earth orbit satellite communication, a storage medium, and an electronic device. Using this method, the terminal does not need to receive satellite broadcast ephemeris data from the downlink channel in advance. Instead, it calculates the satellite ephemeris locally based on the satellite orbital six-element data and combines it with high-precision position data provided by the satellite navigation receiver to directly predict the open-loop satellite-to-end transmission delay. To address the problem of increasing satellite ephemeris calculation errors over time, this method designs a timely uplink delay error detection and feedback scheme. The terminal can use this scheme to obtain the current uplink delay error during idle periods and update the satellite orbital six-element data accordingly, avoiding the impact of accumulated ephemeris calculation errors on satellite-to-end delay prediction.

[0005] Other features and advantages of this application will become apparent from the following detailed description, or may be learned in part from practice of this application.

[0006] According to a first aspect of the embodiments of this application, a comprehensive prediction method for uplink transmission lead time in low-Earth orbit satellite communication is provided, comprising:

[0007] Prepare initial parameters;

[0008] Satellite ephemeris calculation is performed based on the initial parameters to obtain ephemeris data;

[0009] The local time of the ground user terminal is corrected according to the initial parameters;

[0010] The local time after correction is continuously compared with the satellite transit start time, and the position coordinates of the ground user terminal are calculated at each step time after the satellite transit start time.

[0011] Synchronously read ephemeris data and calculate satellite-to-end transmission latency;

[0012] Determine the uplink transmission advance based on the star-to-end transmission delay, and perform uplink synchronization;

[0013] After uplink synchronization, the ground user terminal sends ranging frames to the satellite when the service is idle. The satellite processing payload demodulates the ranging frames to obtain the uplink delay error.

[0014] In some embodiments of this application, based on the foregoing scheme, the preparation of initial parameters includes:

[0015] Obtain the orbital six-point number of the satellite to be used from the satellite operation and control center or onboard broadcast;

[0016] Obtain the position and velocity data of the user station from the satellite navigation receiver;

[0017] Obtain high-precision time information and second pulses from the satellite navigation receiver;

[0018] The timing step for transmitting star-end transmission delay data is determined based on the uplink transmission delay adjustment period, the star-end transmission delay calculation time, and the time it takes for star-end transmission delay data to be transmitted via the internal bus. .

[0019] In some embodiments of this application, based on the foregoing scheme, the step of calculating satellite ephemeris data according to the initial parameters includes:

[0020] The satellite ephemeris is calculated based on the orbital six-element number of the satellite to be used, yielding the satellite's transit start time. Starting from, Store the merged ephemeris datasets with time steps.

[0021] In some embodiments of this application, based on the foregoing scheme, the step of correcting the local time of the ground user terminal according to the initial parameters includes:

[0022] The local time of the ground user terminal is corrected based on the high-precision time information and the second pulse.

[0023] In some embodiments of this application, based on the foregoing scheme, calculating the position coordinates of the ground user terminal at each step time after the satellite transit start time includes:

[0024] Determine the step time using formula (1) ;

[0025] (1)

[0026] in, The start time of satellite transit. The time step for sending data with star-to-end transmission delay;

[0027] Based on step time Formula (2) is used to calculate the step time of the ground user terminal. Position coordinates ;

[0028] (2)

[0029] Among them, ( , , (The last part is a separate sentence fragment and doesn't translate directly.) The speed of the ground user terminal given at all times, ( , , (The last part is a separate sentence fragment and doesn't translate directly.) The location coordinates of the ground user terminal are given at all times.

[0030] In some embodiments of this application, based on the foregoing scheme, the synchronous reading of ephemeris data and calculation of satellite-to-end transmission delay includes:

[0031] Read from the ephemeris data storage area ephemeris data of the moment and combined with The location coordinates of the ground user terminal at any time are used to calculate the star-to-end transmission delay using formula (3);

[0032] (3)

[0033] in, express Star-to-end transmission delay Indicates that the ground user terminal is in Position coordinates at that moment express Ephemeris data for each moment.

[0034] In some embodiments of this application, based on the foregoing scheme, determining the uplink transmission advance based on the star-to-end transmission delay includes:

[0035] Based on star-to-end transmission delay Downlink reception synchronization processing delay The transmission time of the next transmission subframe of the ground user terminal Determine the uplink transmission lead time ;

[0036] (4)

[0037] In some embodiments of this application, based on the foregoing scheme, the following further methods are also included:

[0038] The onboard processing payload transmits the uplink delay error to the ground user terminal via the downlink signaling channel.

[0039] The ground user terminal determines the relationship between the current uplink delay error and the delay error threshold, issues an alarm message, and determines whether the orbital six-element number needs to be updated. If the orbital six-element number needs to be updated, it retrieves the latest satellite orbital six-element number from the downlink broadcast channel and uses the latest satellite orbital six-element number for satellite ephemeris calculation in the next communication.

[0040] According to a second aspect of the embodiments of this application, a computer-readable storage medium is provided, the storage medium storing computer instructions that, when executed on a computer, cause the computer to perform the method as described in the first aspect.

[0041] According to a third aspect of the embodiments of this application, an electronic device is provided, including: a memory and a processor;

[0042] The memory is used to store computer instructions;

[0043] The processor is configured to invoke computer instructions stored in the memory, causing the electronic device to execute the method described in the first aspect.

[0044] The technical solution of this application has the following beneficial effects:

[0045] The uplink open-loop transmission delay prediction based on the six satellite orbital elements for local ephemeris calculation at the terminal has significant advantages such as speed, simplicity, and low resource consumption. It effectively solves the problem of difficult prediction of uplink transmission lead in low-Earth orbit satellite communication and can assist in achieving rapid uplink synchronization.

[0046] To address the issue of satellite ephemeris calculation errors increasing over time, a real-time closed-loop delay prediction scheme is proposed. This scheme consumes fewer resources, has minimal impact on service communication, and compensates for the shortcomings of open-loop delay error prediction.

[0047] This method combines open-loop and closed-loop satellite-to-end delay prediction methods, effectively solving the problem of rapid uplink synchronization in low-Earth orbit burst-mode satellite communication systems, and has good applicability to both ground fixed terminals and "mobile communication" terminals.

[0048] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0049] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0050] Figure 1 A flowchart illustrating a method for comprehensive prediction of uplink transmission lead in low-Earth orbit satellite communication according to an embodiment of this application is shown.

[0051] Figure 2 This illustration shows a ground user terminal determining uplink transmission advance based on satellite-to-end transmission delay according to an embodiment of this application;

[0052] Figure 3 A schematic diagram of the composition of an on-board processing payload according to an embodiment of this application is shown;

[0053] Figure 4 A schematic diagram illustrating the composition of a ground user terminal according to an embodiment of this application is shown;

[0054] Figure 5 A schematic diagram of an uplink ranging frame and a service frame according to an embodiment of this application is shown.

[0055] Figure 6 A block diagram of an electronic device according to one embodiment of this application is shown;

[0056] Figure 7A schematic diagram of the structure of a computer system suitable for implementing the electronic device of the present application is shown. Detailed Implementation

[0057] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0058] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0059] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0060] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0061] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0062] The following detailed description of some embodiments of this application will be provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0063] See Figure 1The diagram shows a flowchart illustrating a method for comprehensively predicting uplink transmission lead time in low-Earth orbit satellite communication according to an embodiment of this application.

[0064] like Figure 1 As shown, a comprehensive prediction method for uplink transmission lead time in low-Earth orbit satellite communication is presented, specifically including steps S100 to S700.

[0065] refer to Figure 1 Step S100: Prepare initial parameters.

[0066] In some feasible embodiments, based on the foregoing scheme, the preparation of initial parameters includes:

[0067] Obtain the orbital six-point number of the satellite to be used from the satellite operation and control center or onboard broadcast;

[0068] Obtain the position and velocity data of the user station from the satellite navigation receiver;

[0069] Obtain high-precision time information and second pulses from the satellite navigation receiver;

[0070] The timing step for transmitting star-end transmission delay data is determined based on the uplink transmission delay adjustment period, the star-end transmission delay calculation time, and the time it takes for star-end transmission delay data to be transmitted via the internal bus.

[0071] It should be noted that, initially, the orbital six-point number of the satellite to be used is provided by the satellite operation and control center, and can be obtained through onboard broadcast after downlink synchronization.

[0072] It should be noted that the coordinate system for the user station's position and velocity is the WGS84 coordinate system.

[0073] It should be noted that the time step of data transmission delay between the satellite and the terminal is... The determination process is as follows:

[0074] (1)

[0075] Indicates the uplink transmission delay adjustment period. Calculate the time for star-to-end transmission delay. The time it takes for satellite-to-satellite transmission delay data to be sent via the internal bus.

[0076] Continue to refer to Figure 1 Step S200: Calculate the satellite ephemeris based on the initial parameters to obtain ephemeris data.

[0077] In some feasible embodiments, based on the foregoing scheme, the step of calculating satellite ephemeris data according to the initial parameters includes:

[0078] The satellite ephemeris is calculated based on the orbital root numbers of the satellite to be used, and the ephemeris data is obtained.

[0079] It should be noted that the ephemeris data here refers to the time-stamped position coordinates of the satellite in the WGS84 coordinate system during the satellite's transit time, with the start time of the time stamp being the start time of the satellite's transit. Step for .

[0080] It should be noted that the calculated ephemeris data will be stored in order to facilitate subsequent use of the ephemeris data.

[0081] Continue to refer to Figure 1 Step S300: Correct the local time of the ground user terminal according to the initial parameters.

[0082] In some feasible embodiments, based on the foregoing scheme, the step of correcting the local time of the ground user terminal according to the initial parameters includes:

[0083] The local time of the ground user terminal is corrected based on the high-precision time information and the second pulse.

[0084] Continue to refer to Figure 1 In step S400, the corrected local time and the satellite transit start time are continuously compared, and the location coordinates of the ground user terminal are calculated at each step time after the satellite transit start time.

[0085] In some feasible embodiments, based on the foregoing scheme, calculating the position coordinates of the ground user terminal at each step after the satellite transit start time includes:

[0086] Determine the step time using formula (2) ;

[0087] (2)

[0088] in, The start time of satellite transit. The time step for sending data with star-to-end transmission delay;

[0089] Based on step time Formula (3) is used to calculate the step time of the ground user terminal. Position coordinates ;

[0090] (3)

[0091] in,( , , (The last part is a separate sentence fragment and doesn't translate directly.) The speed of the ground user terminal given at all times, ( , , (The last part is a separate sentence fragment and doesn't translate directly.) The location coordinates of the ground user terminal are given at all times.

[0092] Continue to refer to Figure 1 Step S500: Synchronously read ephemeris data and calculate satellite-to-end transmission delay.

[0093] In some feasible embodiments, based on the foregoing scheme, the synchronous reading of ephemeris data and the calculation of satellite-to-end transmission delay include:

[0094] Read from the ephemeris data storage area ephemeris data of the moment and combined with The location coordinates of the ground user terminal at any time are used to calculate the star-to-end transmission delay using formula (4);

[0095] (4)

[0096] in, express The star-to-end transmission delay at any given moment. Indicates that the ground user terminal is in Position coordinates at that moment Indicates that the ground user terminal is in Ephemeris data for each moment.

[0097] Continue to refer to Figure 1 In step S600, the uplink transmission advance is determined based on the star-to-end transmission delay, and uplink synchronization is performed.

[0098] In some feasible embodiments, based on the foregoing scheme, determining the uplink transmission advance based on the star-to-end transmission delay includes:

[0099] Based on star-to-end transmission delay Downlink reception synchronization processing delay The transmission time of the next transmission subframe of the ground user terminal Determine the uplink transmission lead time ;

[0100] (5)

[0101] For example, such as Figure 2As shown, assume that the transmit subframe 0 and receive subframe 0 of each frame on the satellite are allocated to the current terminal. The satellite's transmit and receive frame plans start at the same time, and the terminal's transmit and receive frame plans start at the same time but lag behind the satellite's. , For downlink synchronization, star-to-end transmission delay, The downlink reception synchronization processing delay is a known, fixed value. Afterwards, the terminal proceeds according to... The transmission lead time is estimated periodically. In the absence of satellite-to-end transmission delay, the terminal determines the transmission time of the next subframe 0 based on the uplink frame plan. To ensure that the next subframe 0 from the terminal arrives on time according to the satellite's next receiving subframe 0, the uplink transmission of relative... The lead time is:

[0102] (5)

[0103] in Distance The most recent transmission delay is estimated by formula (4).

[0104] Continue to refer to Figure 1 In step S700, after uplink synchronization, the ground user terminal sends ranging frames to the satellite when the service is idle. The satellite processing payload demodulates the ranging frames to obtain the uplink delay error.

[0105] It should be noted that the ranging function is only triggered when there is no business data.

[0106] In some feasible embodiments, based on the foregoing scheme, with reference to Figure 1 This method also includes:

[0107] In step S800, the onboard processing payload sends the uplink delay error to the ground user terminal via the downlink signaling channel;

[0108] In step S900, the ground user terminal determines the relationship between the current uplink delay error and the delay error threshold, issues an alarm message, and determines whether the orbital six-root count needs to be updated. If the orbital six-root count needs to be updated, the latest satellite orbital six-root count is retrieved from the downlink broadcast channel, and the latest satellite orbital six-root count is used for satellite ephemeris calculation in the next communication.

[0109] The following provides a detailed implementation process for this method:

[0110] The composition of on-board processing payloads is as follows: Figure 3As shown, it mainly includes a user baseband processing unit, a protocol processing unit, and an attitude and orbit control unit. The user baseband processing unit primarily performs demodulation, decoding, and deframing of uplink signals, and framing, encoding, and modulation of downlink signals. The protocol processing unit, in addition to performing protocol and data processing during normal communication, also transmits the satellite-to-end delay error data reported by the baseband processing unit and the satellite orbit elements provided by the attitude and orbit control unit to the terminal via the downlink signaling channel.

[0111] The main components of the terminal are as follows Figure 4 As shown, it comprises a human-machine interface, a satellite navigation receiver, a comprehensive control unit, a time synchronization unit, an ephemeris calculation and processing unit, an ephemeris data storage unit, a satellite-to-end transmission delay calculation and transmission unit, an uplink transmission delay adjustment unit, uplink and downlink data processing units, a baseband processing unit (including an uplink baseband processing unit and a downlink baseband processing unit), and an intermediate frequency processing unit. The functions of each component are as follows:

[0112] 1) The human-machine interface provides the terminal with the working parameters required to implement this method and displays the relevant working status during the implementation of this method;

[0113] 2) The satellite navigation receiver provides terminal position data, velocity data, BeiDou whole-second cumulative time, and second pulse in the WGS84 coordinate system;

[0114] 3) The main function of the integrated control unit is to provide interfaces for other units within the terminal, the human-machine interface, and the satellite navigation receiver;

[0115] 4) The time synchronization unit continuously and precisely corrects the local time based on the time and second pulse provided by the satellite navigation receiver;

[0116] 5) The ephemeris calculation and processing unit mainly extrapolates the ephemeris parameters in the WGS84 coordinate system for a future time period based on the six orbital roots of the satellite using the numerical integration method;

[0117] 6) The ephemeris data storage unit is used to store the ephemeris data given by the ephemeris processing unit. The stored content is mainly satellite position coordinates with time tags.

[0118] 7) The main functions of the satellite-to-end transmission delay calculation and transmission unit are: to determine the position of the transmission time based on the terminal position and speed data provided by the satellite navigation receiver last time, and to calculate the satellite-to-end transmission delay at the transmission time according to formula (4) in combination with the ephemeris data of the transmission time, and then send it to the uplink transmission delay adjustment unit through the high-speed internal bus.

[0119] 8) The function of the uplink transmission delay adjustment unit is to control the transmission advance of the uplink baseband processing unit in the next subframe based on the star-to-end transmission delay calculation value.

[0120] 9) The uplink baseband processing unit completes the framing, encoding, and modulation of uplink signaling and service data during normal service communication, and completes the framing, encoding, and modulation of ranging frames during service idle time;

[0121] 10) The downlink baseband processing unit completes the demodulation, decoding, and deframing of downlink signaling and service data;

[0122] 11) In addition to processing uplink and downlink service data, the uplink and downlink data processing unit also controls the activation of the baseband uplink ranging function and extracts the uplink delay error value fed back from the satellite from the downlink signaling channel data.

[0123] After the terminal and satellite navigation receiver are powered on and initialized, the satellite navigation receiver periodically sends position and velocity information in the WGS84 coordinate system and BeiDou integer second accumulation value to the terminal through the UART serial port, and sends second pulses to the ground user terminal through the RS422 discrete interface.

[0124] Users configure initial parameters such as the orbital root number of the satellite to be used, the start time of ephemeris data calculation, the calculation duration, and the calculation step size through the human-machine interface. The start time of ephemeris data is determined based on the start time of the satellite's transit, the duration is determined by the transit time of the satellite, and the calculation step size is selected according to formula (1). In this embodiment, the uplink transmission delay adjustment period is 10ms, the delay calculation time is 1ms, the delay data transmission time is 1ms, and after considering a certain margin, the calculation step size is selected as 2ms.

[0125] Considering the limitations of terminal computing and storage speed, the ephemeris calculation and storage of the satellite to be used must be completed before the time of use arrives. In this embodiment, the ephemeris data of the satellite to be used for the next 15 minutes can be calculated and stored within 3 minutes. Therefore, the time to start ephemeris calculation should be at least 3 minutes before the time of use.

[0126] After receiving the initial parameters, the ephemeris processing unit begins to perform ephemeris calculations using a high-precision orbit extrapolation algorithm and sends the ephemeris data to the ephemeris data storage unit for storage. During communication with the current satellite, it also completes the ephemeris data calculation and storage for the next satellite in advance.

[0127] The time synchronization unit corrects the local time based on the BeiDou integer second accumulation value and second pulse provided by the satellite navigation receiver. The corrected local time is then sent to the satellite-end delay calculation and transmission unit in the form of a 1ms timer interrupt.

[0128] The satellite-to-end transmission delay calculation and transmission unit compares the local time and the start time of the ephemeris data. If they are equal, it means that the transmission time has arrived. Immediately, the current position data of the user station is obtained according to formula (3) based on the terminal position and speed data sent by the satellite navigation receiver last time. At the same time, the ephemeris data of the current time is read from the memory and the current satellite-to-end transmission delay is calculated according to formula (4). After the calculation is completed, it is sent to the uplink transmission delay adjustment unit through the internal bus. Then, an ephemeris data time step is added, and the above calculation and transmission process is repeated.

[0129] The uplink transmission delay adjustment unit adjusts the transmission advance of the next uplink subframe of this terminal according to the received star-to-end transmission delay data according to formula (5), so that the arrival time of the transmission subframe on the satellite is accurately aligned with the start time of the satellite receiving the subframe, thus assisting the uplink to complete synchronization.

[0130] During periods of low service activity, the terminal automatically sends ranging frames to the onboard processing payload. For example... Figure 5 As shown, the uplink ranging frame and the service frame have the same frame length and symbol rate (frame length is 10ms, symbol rate is 2.56Msps), the modulation scheme is BPSK, and the frame content is an M-sequence. The baseband processing unit demodulates, matches, filters, extracts, and stores 512 symbol data from the uplink ranging frame. Then, it reads 256 sampled values ​​serially at 4x intervals and correlates them with the local PN code to obtain 1024 correlation values ​​C(k), where k = 0 ~ 1023. Under the condition of decision synchronization, the uplink delay synchronization error is:

[0131] ;

[0132] in, To make C(k) reach its maximum value, Negative numbers indicate leading, while positive numbers indicate lagging.

[0133] The baseband processing unit on the satellite payload reports the estimated uplink delay error to the protocol processing unit. The protocol processing unit packages this information into downlink signaling data and sends it to the terminal through the downlink signaling channel. After receiving the estimated uplink delay error data, the terminal compares it with the uplink delay error threshold (set to 3µs in this embodiment). If the delay error reaches the threshold, the terminal actively receives the latest satellite orbital root count through the downlink broadcast channel. In the next communication, the terminal automatically uses the latest satellite orbital root count to calculate the satellite-to-terminal transmission delay and displays the alarm information on the human-machine interface until the estimated delay error is less than the error threshold.

[0134] like Figure 6As shown, this application embodiment also provides an electronic device 600, including a memory 610, a processor 620, and a computer program 611 stored in the memory 610 and executable on the processor. When the processor 620 executes the computer program 611, it implements the steps of the above-mentioned method for comprehensive prediction of uplink transmission lead in low-orbit satellite communication.

[0135] Since the electronic device described in this embodiment is the device used to implement the comprehensive prediction method for uplink transmission advance of low-orbit satellite communication in the embodiments of this application, those skilled in the art can understand the specific implementation method and various variations of the electronic device in this embodiment based on the method described in the embodiments of this application. Therefore, how the electronic device implements the method in the embodiments of this application will not be described in detail here. Any device used by those skilled in the art to implement the method in the embodiments of this application falls within the scope of protection of this application.

[0136] In practice, when the computer program 611 is executed by the processor, it can implement any of the embodiments corresponding to the first aspect.

[0137] Figure 7 A schematic diagram of the structure of a computer system suitable for implementing the electronic device of the present application is shown.

[0138] It should be noted that, Figure 7 The computer system 700 of the electronic device shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0139] like Figure 7 As shown, the computer system 700 includes a Central Processing Unit (CPU) 701, which can perform various appropriate actions and processes based on programs stored in Read-Only Memory (ROM) 702 or programs loaded from storage portion 708 into Random Access Memory (RAM) 703, such as performing the methods described in the above embodiments. The RAM 703 also stores various programs and data required for system operation. The CPU 701, ROM 702, and RAM 703 are interconnected via a bus 704. An Input / Output (I / O) interface 705 is also connected to the bus 704.

[0140] The following components are connected to I / O interface 705: an input section 706 including a keyboard, mouse, etc.; an output section 707 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 708 including a hard disk, etc.; and a communication section 709 including a network interface card such as a LAN (Local Area Network) card, modem, etc. The communication section 709 performs communication processing via a network such as the Internet. A drive 710 is also connected to I / O interface 705 as needed. A removable medium 711, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on drive 710 as needed so that computer programs read from it can be installed into storage section 708 as needed.

[0141] Specifically, according to embodiments of this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 709, and / or installed from removable medium 711. When the computer program is executed by central processing unit (CPU) 701, it performs various functions defined in the system of this application.

[0142] It should be noted that the computer-readable medium shown in the embodiments of this application can be a computer-readable signal medium, a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this application, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such transmitted data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0143] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. Each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0144] The units described in the embodiments of this application can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0145] In another aspect, this application also provides a computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the comprehensive prediction method for uplink transmission lead in low-Earth orbit satellite communication described in the above embodiments.

[0146] In another aspect, this application also provides a computer-readable medium, which may be included in the electronic device described in the above embodiments; or it may exist independently and not assembled into the electronic device. The computer-readable medium carries one or more programs, which, when executed by the electronic device, cause the electronic device to implement the comprehensive prediction method for uplink transmission lead of low-Earth orbit satellite communication described in the above embodiments.

[0147] It should be noted that although several modules or units for the device used to perform actions have been mentioned in the detailed description above, this division is not mandatory. In fact, according to the embodiments of this application, the features and functions of two or more modules or units described above can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units.

[0148] Through the above description of the embodiments, those skilled in the art will readily understand that the exemplary embodiments described herein can be implemented by software or by combining software with necessary hardware. Therefore, the technical solutions according to the embodiments of this application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, external hard drive, etc.) or on a network, including several instructions to cause a computing device (such as a personal computer, server, touch terminal, or network device, etc.) to execute the methods according to the embodiments of this application.

[0149] Other embodiments of this application will readily conceive of by those skilled in the art upon consideration of the specification and practice of the embodiments disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. It should be understood that this application is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A comprehensive prediction method for uplink transmission lead in low-Earth orbit satellite communication, characterized in that, include: Prepare initial parameters; Satellite ephemeris calculation is performed based on the initial parameters to obtain ephemeris data; The local time of the ground user terminal is corrected according to the initial parameters; The local time after correction is continuously compared with the satellite transit start time, and the position coordinates of the ground user terminal are calculated at each step time after the satellite transit start time. Synchronously read ephemeris data and calculate satellite-to-end transmission latency; Determine the uplink transmission advance based on the star-to-end transmission delay, and perform uplink synchronization; After uplink synchronization, the ground user terminal sends ranging frames to the satellite when the service is idle. The satellite processing payload demodulates the ranging frames to obtain the uplink delay error. The preparation of initial parameters includes: Obtain the orbital six-point number of the satellite to be used from the satellite operation and control center or onboard broadcast; Obtain the position and velocity data of the user station from the satellite navigation receiver; Obtain high-precision time information and second pulses from the satellite navigation receiver; The timing step for transmitting star-end transmission delay data is determined based on the uplink transmission delay adjustment period, the star-end transmission delay calculation time, and the transmission time of star-end transmission delay data via the internal bus. .

2. The method according to claim 1, characterized in that, The step of calculating satellite ephemeris data based on the initial parameters includes: The satellite ephemeris is calculated based on the orbital six-element number of the satellite to be used, yielding the satellite's transit start time. Starting from, Store the merged ephemeris datasets with time steps.

3. The method according to claim 1, characterized in that, The step of correcting the local time of the ground user terminal based on the initial parameters includes: The local time of the ground user terminal is corrected based on the high-precision time information and the second pulse.

4. The method according to claim 2, characterized in that, The calculation of the ground user terminal's position coordinates at each step after the satellite's transit start time includes: Determine the step time using formula (1) ; （1） in, The start time of satellite transit. The time step for sending data with star-to-end transmission delay; Based on step time Formula (2) is used to calculate the step time of the ground user terminal. Position coordinates ; （2） in,( , , (The last part is a separate sentence fragment and doesn't translate directly.) The speed of the ground user terminal given at all times, ( , , (The last part is a separate sentence fragment and doesn't translate directly.) The location coordinates of the ground user terminal are given at all times.

5. The method according to claim 4, characterized in that, The synchronous reading of ephemeris data and calculation of satellite-to-end transmission delay includes: Read from the ephemeris data storage area ephemeris data of the moment and combined with The location coordinates of the ground user terminal at any time are used to calculate the star-to-end transmission delay using formula (3); （3） in, express The star-to-end transmission delay at any given moment. Indicates ground user terminal Position coordinates at that moment express Ephemeris data for each moment.

6. The method according to claim 5, characterized in that, The determination of uplink transmission advance based on star-to-end transmission delay includes: Based on star-to-end transmission delay Downlink reception synchronization processing delay The transmission time of the next transmission subframe of the ground user terminal Determine the uplink transmission lead time ; （4）。 7. The method according to any one of claims 1-6, characterized in that, Also includes: The onboard processing payload transmits the uplink delay error to the ground user terminal via the downlink signaling channel. The ground user terminal determines the relationship between the current uplink delay error and the delay error threshold, issues an alarm message, and determines whether the orbital six-element number needs to be updated. If the orbital six-element number needs to be updated, it retrieves the latest satellite orbital six-element number from the downlink broadcast channel and uses the latest satellite orbital six-element number for satellite ephemeris calculation in the next communication.

8. A computer-readable storage medium, characterized in that, The storage medium stores computer instructions that, when executed on a computer, cause the computer to perform the method as described in any one of claims 1-7.

9. An electronic device, characterized in that, include: Memory and processor; The memory is used to store computer instructions; The processor is configured to invoke computer instructions stored in the memory, causing the electronic device to perform the method as described in any one of claims 1-7.

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