An autonomous management method and device for on-satellite time of a satellite cluster

Abstract

An embodiment of the present invention provides a method and device for autonomous management of on-board time in a satellite cluster. The method includes: obtaining the time of the central management unit, where the time of the central management unit is the on-board time of the main satellite; correcting the on-board time of the main satellite according to the time of the central management unit, the time generated by the GNSS system, and the ground time; using the corrected on-board time of the main satellite and the ground time to correct the time of the inter-satellite link processor; and correcting the on-board time of the slave satellite according to the corrected on-board time of the main satellite, the corrected time of the inter-satellite link processor, and the ground time, so as to achieve autonomous management of on-board time in the satellite cluster. In this solution, by configuring a GNSS system on the main satellite and according to the time of the central management unit and the time generated by the GNSS system, the correction and synchronization of the satellite time in the entire satellite cluster can be achieved. After calibration only at the initial stage of satellite orbit insertion, the satellite cluster can achieve autonomous management of satellite time during the entire satellite life cycle.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of satellite autonomous operation, and particularly to an autonomous management method and device for on-board time of a satellite cluster. Background Art

[0002] Generally, during the on-orbit operation of a satellite, there is support from a ground measurement and control station. The ground measurement and control station can generally measure and control the on-orbit operation of the satellite in real time. During the measurement and control period, the difference between the on-board time and the ground reference time can be monitored and measured through the ground measurement and control station, and when it exceeds the allowable threshold, the satellite is timely calibrated to ensure that the difference between the satellite time and the ground time is within a reasonable range.

[0003] In related technologies, for satellites operating autonomously in orbit, there is generally no support from a ground measurement and control station during their long-term operation, and the satellite time cannot be autonomously calibrated. Usually, such satellites are generally equipped with an inter-satellite link subsystem, which establishes an information transmission link with satellites in the constellation that have ground measurement and control station support through microwave or laser communication, so as to transmit their own engineering measurement and control data and payload service data. Whether the attitude pointing of the satellite is accurate and whether the relative position of two satellites is accurate are very important for the acquisition and maintenance of the inter-satellite link; and the accuracy of the on-board time is a key factor affecting the accuracy of satellite attitude determination and control and the calculation of the relative position of two satellites. Therefore, in order to ensure the normal operation of the constellation service and achieve autonomous calibration of the on-board time of the satellite cluster, it is not only necessary to accurately unify the time of the on-board computer and the inter-satellite link processor within the same satellite, but also necessary to highly unify the time of each satellite in the constellation.

[0004] Therefore, based on the above problems, there is an urgent need to provide an autonomous management method and device for on-board time of a satellite cluster. Summary of the Invention

[0005] In order to solve the problem that autonomous on-orbit satellites without ground measurement and control station support cannot achieve autonomous calibration of on-board time, the embodiments of the present invention provide an autonomous management method and device for on-board time of a satellite cluster.

[0006] In a first aspect, the embodiments of the present invention provide an autonomous management method for on-board time of a satellite cluster, including:

[0007] Obtain the time of the central management unit; wherein, the time of the central management unit is the satellite time of the master satellite;

[0008] Correct the satellite time of the master satellite according to the time of the central management unit, the time generated by the GNSS system, and the ground time;

[0009] Use the corrected satellite time of the master satellite and the ground time to correct the time of the inter-satellite link processor;

[0010] Calibrate the satellite time of the slave satellite according to the satellite time of the master satellite after calibration, the time of the inter-satellite link processor after calibration, and the ground time, so as to realize the autonomous management of the on-board time of the satellite cluster.

[0011] In a second aspect, an embodiment of the present invention further provides an apparatus for autonomous management of on-board time of a satellite cluster, including:

[0012] An acquisition unit, configured to acquire the time of the central management unit; wherein, the time of the central management unit is the satellite time of the master satellite;

[0013] A first calibration unit, configured to calibrate the satellite time of the master satellite according to the time of the central management unit, the time generated by the GNSS system, and the ground time;

[0014] A second calibration unit, configured to calibrate the time of the inter-satellite link processor by using the satellite time of the master satellite after calibration and the ground time;

[0015] A third calibration unit, configured to calibrate the satellite time of the slave satellite according to the satellite time of the master satellite after calibration, the time of the inter-satellite link processor after calibration, and the ground time, so as to realize the autonomous management of the on-board time of the satellite cluster.

[0016] In a third aspect, an embodiment of the present invention further provides an electronic device, including a memory and a processor. A computer program is stored in the memory. When the processor executes the computer program, the method described in any embodiment of this specification is implemented.

[0017] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed on a computer, the computer is made to execute the method described in any embodiment of this specification.

[0018] An embodiment of the present invention provides a method and apparatus for autonomous management of on-board time of a satellite cluster. First, calibrate the satellite time of the master satellite according to the time of the central management unit and the time generated by the GNSS system. Then, calibrate the time of the inter-satellite link processor by using the satellite time of the master satellite after calibration and the ground time. Finally, calibrate the satellite time of the slave satellite by using the satellite time of the master satellite after calibration, the time of the inter-satellite link processor after calibration, and the ground time, so as to realize the autonomous management of the on-board time of the satellite cluster. In this solution, by configuring a GNSS system on the master satellite, the calibration and synchronization of the satellite time in the entire satellite cluster are realized according to the time of the central management unit and the time generated by the GNSS system. At the same time, only after calibration in the initial stage of satellite orbit injection, the satellite cluster can realize the autonomous management of satellite time during the entire satellite life cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0020] Figure 1 It is a flowchart of a method for autonomous management of on-board time of a satellite cluster provided by an embodiment of the present invention;

[0021] Figure 2 It is a hardware architecture diagram of an electronic device provided by an embodiment of the present invention;

[0022] Figure 3 It is a structural diagram of a device for autonomous management of on-board time of a satellite cluster provided by an embodiment of the present invention. Detailed implementation manners

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0024] Please refer to Figure 1 , an embodiment of the present invention provides a method for autonomous management of on-board time of a satellite cluster, and the method includes:

[0025] Step 100: Obtain the time of the central management unit; wherein, the time of the central management unit is the on-board time of the main satellite;

[0026] Step 102: Correct the on-board time of the main satellite according to the time of the central management unit, the time generated by the GNSS system, and the ground time;

[0027] Step 104: Correct the time of the inter-satellite link processor by using the corrected on-board time of the main satellite and the ground time;

[0028] Step 106: Correct the on-board time of the slave satellite according to the corrected on-board time of the main satellite, the corrected time of the inter-satellite link processor, and the ground time, so as to realize the autonomous management of on-board time of the satellite cluster.

[0029] In the embodiment of the present invention, first, the satellite time of the main satellite is corrected according to the time of the central management unit and the time generated by the GNSS system. Then, the time of the inter-satellite link processor is corrected by using the corrected satellite time of the main satellite and the ground time. Finally, the satellite time of the slave satellite is corrected by using the corrected satellite time of the main satellite, the corrected time of the inter-satellite link processor, and the ground time, so as to realize the autonomous management of the on-board time of the satellite cluster. In this solution, by configuring a GNSS system on the main satellite and according to the time of the central management unit and the time generated by the GNSS system, the time correction and synchronization of the satellites in the entire satellite cluster are realized. At the same time, only after calibration in the initial stage of satellite orbit injection, the satellite cluster can realize the autonomous management of satellite time during the entire satellite life cycle.

[0030] The execution manners of the following described Figure 1 each step are shown.

[0031] For step 100:

[0032] In this embodiment, first, any satellite in the satellite cluster can be designated as the main satellite, and a GNSS system (Global Navigation Satellite System) is configured on the main satellite. The central management unit of the on-board computer of the main satellite detects the satellite time of the main satellite in real time, and compares the satellite time of the main satellite with the time generated by the GNSS system, and realizes the correction of the satellite time of the main satellite through the interaction between the on-board computer of the main satellite and the GNSS system.

[0033] In some embodiments, step 102 may include steps S1 to S5:

[0034] S1. Calculate the time sent from the central management unit to the GNSS system according to the time of the central management unit and the first initial time delay error;

[0035] S2. Calculate the satellite-ground time difference according to the time sent from the central management unit to the GNSS system and the time generated by the CNSS system;

[0036] S3. Determine whether the satellite-ground time difference exceeds the preset range. If so, determine the sum of the satellite-ground time difference and the time of the central management unit as the current satellite time of the main satellite;

[0037] S4. If not, determine the time of the central management unit as the current satellite time of the main satellite;

[0038] S5. Calculate the current first time delay error according to the current satellite time of the main satellite and the ground time, and use the first time delay error as the first initial time delay error to repeat steps S1 to S4 until the satellite time of the main satellite meets the preset requirements, so as to complete the correction of the satellite time of the main satellite.

[0039] In this embodiment, first, the central management unit of the main satellite regularly sends the satellite time to the GNSS system via the bus. Generally speaking, there are time delay errors in the links from software-packaged satellite time to transmission, bus transmission, and GNSS receiver processing. Therefore, the time sent by the central management unit to the GNSS system is:

[0040] t = t sat + △t0

[0041] In the formula, t is the time sent by the central management unit to the GNSS system, t sat is the time of the central management unit, and △t0 is the first initial time delay error; in this embodiment, the first initial time delay error is usually set to 0.

[0042] After the GNSS system receives the satellite time sent by the central management unit, it calculates the satellite-ground time difference based on the time generated by the GNSS system (this time is consistent with the ground time reference) and the time of the central management unit received:

[0043] △t = t GNSS - t

[0044] In the formula, △t is the satellite-ground time difference, t GNSS is the time generated by the GNSS system, and t is the time sent by the central management unit to the GNSS system.

[0045] After that, the GNSS system sends the calculated satellite-ground time difference to the central management unit of the main satellite. The on-board computer of the main satellite judges and verifies the rationality of the satellite-ground time difference. If the satellite-ground time difference does not exceed the pre-set time calibration protection range, the satellite time of the main satellite is corrected using this satellite-ground time difference. At this time, the satellite time of the main satellite is: t' sat = t sat + △t; if the satellite-ground time difference exceeds the pre-set time calibration protection range, this satellite-ground time difference is not used to correct the satellite time of the main satellite. At this time, the satellite time of the main satellite is t' sat = t sat . To ensure the stability of the on-board computer operation, considering that a backup central management unit is usually set, when the primary central management unit fails, in order to smoothly switch the central management unit to the backup central management unit and ensure the accuracy of the main satellite time calibration process, the time calibration protection range is set to two groups in this embodiment: {[-T1, T1], [-T2, T2]}, where [-T1, T1] is the fine threshold, which is used during the long-term operation of the satellite, and [-T2, T2] is the coarse threshold, which is only used once after the central management unit switches to the backup machine.

[0046] In some embodiments, calculating the current first time delay error based on the time of the current central management unit and the ground time includes:

[0047] Obtain the satellite time of the main satellite and the ground time at multiple time measurement points through the telemetry system;

[0048] Calculate the first satellite-ground time difference at each time measurement point respectively according to the difference between the satellite time of the main satellite and the ground time at each time measurement point;

[0049] Determine the average value of the first satellite-ground time differences at multiple time measurement points as the current first time delay error.

[0050] In this embodiment, after the satellite time of the central management unit of the main satellite (i.e., the satellite time of the main satellite) is stable, collect the satellite time of the main satellite at multiple time measurement points and the ground time at multiple time measurement points through the satellite telemetry system, and calculate the difference between the satellite time of the main satellite and the ground time (i.e., the first satellite-ground time difference) delta_T[0], delta_T[1], ……, delta_T[n] at each time measurement point. Then, take the average value delta_T = (delta_T[0] + delta_T[1] + … + delta_T[n]) / n of the first satellite-ground time differences at multiple time measurement points as the current first time delay error, and inject this time delay error into the central management unit of the main satellite to make it replace the first initial time delay error and continue to correct the satellite time of the main satellite until the satellite time of the main satellite meets the preset accuracy requirements.

[0051] When there is no support from the ground measurement and control station, each satellite in the satellite cluster is interconnected through an inter-satellite link to form a space communication network. Therefore, in order to achieve the synchronization of the on-satellite time in the satellite cluster, in this embodiment, first correct the satellite time of the main satellite. After the satellite time of the main satellite meets the preset accuracy requirements, start to correct the time of the inter-satellite link processor in the satellite, and finally correct the satellite time of the slave satellite.

[0052] Regarding step 104:

[0053] In some embodiments, step 104 may include:

[0054] Calculate the time for the central management unit to time the inter-satellite link processor according to the corrected satellite time of the main satellite and the second initial time delay error;

[0055] Determine the timed time as the current time of the inter-satellite link processor;

[0056] Calculate the current second time delay error according to the current time of the inter-satellite link processor and the ground time, and use this second time delay error as the second initial time delay error to repeat the calculation step of the timed time and the determination step of the time of the inter-satellite link processor until the time of the inter-satellite link processor meets the preset requirements to complete the correction of the time of the inter-satellite link processor.

[0057] In this embodiment, when calibrating the time of the inter-satellite link processor, the central management unit of the master satellite regularly synchronizes the time of the inter-satellite link processor via the bus. There will be time delay errors in all links from software time packaging to transmission, bus transmission, and receiver processing. Denote the total time delay error in each link as the second time delay error △t1. Then the time t1 for the master satellite to synchronize the time to the inter-satellite link processor is t1 = t sat +△t1; After receiving the time from the master satellite, the inter-satellite link processor calibrates its time with this synchronized time, that is, determines the synchronized time as the time of the inter-satellite link processor.

[0058] Calculating the current second time delay error based on the current time of the inter-satellite link processor and the ground time includes:

[0059] Obtaining the time of the inter-satellite link processor and the ground time at multiple time measurement points through the telemetry system;

[0060] Calculating the second satellite-ground time difference at each time measurement point according to the difference between the time of the inter-satellite link processor and the ground time at each time measurement point;

[0061] Determining the average value of the second satellite-ground time differences at multiple time measurement points as the current second time delay error.

[0062] After the time of the inter-satellite link processor is stable, obtain the time of the inter-satellite link processor and the ground time at multiple time measurement points through the service telemetry system, and calculate the difference between the time of the inter-satellite link processor and the ground time (i.e., the second satellite-ground time difference) delta_T1[0], delta_T1[1], ……, delta_T1[n] at each time measurement point. Then take the average value delta_T1 = (delta_T1[0] + delta_T1[1] + … + delta_T1[n]) / n of the second satellite-ground time differences at multiple time measurement points as the current second time delay error, and inject this time delay error into the inter-satellite link processor to replace the second initial time delay error to continue calibrating the satellite time of the inter-satellite link processor until the time of the inter-satellite link processor meets the preset accuracy requirements.

[0063] In this embodiment, after completing the calibration of the inter-satellite link processing time, it also includes calibrating the time of the payload controller in the satellite cluster. It should be noted that the time calibration method of the payload controller is the same as that of the inter-satellite link processor time.

[0064] Regarding step 106:

[0065] In some embodiments, step 106 may include:

[0066] Calculating the time for the master satellite to synchronize the time to the slave satellite through the inter-satellite link processor according to the calibrated satellite time of the master satellite and the third initial time delay error;

[0067] Determine the star time of the current slave satellite as the time determined by the star-based time service;

[0068] According to the star time of the current slave satellite and the ground time, calculate the current third time delay error, and use this third time delay error as the third initial time delay error to repeatedly execute the calculation step of the time service time of the slave satellite and the determination step of the star time of the slave satellite until the star time of the slave satellite meets the preset requirements to complete the correction of the star time of the slave satellite.

[0069] In this embodiment, the master satellite regularly sends the star time of the master satellite to the slave satellite through the inter-satellite link. There will be time delay errors in all links from software packaging the star time to sending, inter-satellite transmission, and slave satellite receiving end processing. In this embodiment, the distance between the master satellite and the slave satellite is denoted as L, and the total time delay error of other delays except the inter-satellite transmission delay is denoted as △t2. Then the time for the master satellite to perform time service for the slave satellite through the inter-satellite link is:

[0070] t=t sat +△t2+L / c

[0071] In the formula, t sat is the time of the central management unit, △t2 is the third initial time delay error, L is the distance between the master satellite and the slave satellite, and c is the speed of light; after the slave satellite receives the time service time sent by the master satellite, it uses this time service time to correct the star time of the slave satellite, that is, determines this time service time as the star time of the slave satellite.

[0072] It should be noted that in this embodiment, the first initial time delay error △t, the second initial time delay error △t1, and the third initial time delay error △t2 are all 0.

[0073] In some embodiments, the slave satellite time and the ground time at multiple time measurement points are obtained through the ground measurement and control station;

[0074] According to the difference between the slave satellite time and the ground time at each time measurement point, calculate the third satellite-ground time difference at each time measurement point respectively;

[0075] Determine the average value of the third satellite-ground time differences at multiple time measurement points as the current third time delay error.

[0076] When the satellite time of the slave satellite is stabilized, the satellite time of the slave satellite and the ground time at multiple time measurement points are obtained through the ground TT&C station, and the difference between the satellite time of the slave satellite and the ground time at each time measurement point (i.e., the third satellite-ground time difference) delta_T2[0], delta_T2[1], ……, delta_T2[n] is calculated. Then, the average value delta_T2 = (delta_T2[0] + delta_T2[1] + … + delta_T2[n]) / n of the second satellite-ground time differences at multiple time measurement points is taken as the current third time delay error, and this time delay error is injected into the slave satellite to replace the third initial time delay error and continue to correct the satellite time of the slave satellite until the time of the slave satellite meets the preset accuracy requirements.

[0077] In the embodiment of the present invention, any satellite in the specified satellite cluster is designated as the master satellite, and a GNSS system is configured on the master satellite. The transmission and sending of information between the central management unit of the master satellite and the GNSS system are used to correct the satellite time of the master satellite, and then time is provided to other on-board units that require precise time (such as the inter-satellite link processor or the payload controller). After the time of the master satellite and the inter-satellite link processor is unified, the correction of the satellite time of the slave satellite is started. The master satellite sends the satellite time to the slave satellite through the inter-satellite link, and the slave satellite corrects the satellite time after receiving the time correction data, thereby realizing the synchronization of the satellite time in the satellite cluster.

[0078] In summary, in this embodiment, after calibrating the satellite time of the satellite cluster once by using the ground TT&C station in the initial stage of satellite orbit injection, during the life cycle of the satellite cluster, without the support of the TT&C station, the satellite can independently manage and synchronize the time of the master satellite and the slave satellite on board.

[0079] As Figure 2 、 Figure 3 shown, the embodiment of the present invention provides an on-board autonomous management device for satellite cluster satellite time. The device embodiment can be implemented through software, or through hardware or a combination of software and hardware. From a hardware perspective, as Figure 2 shown, it is a hardware architecture diagram of an electronic device where the on-board autonomous management device for satellite cluster satellite time provided by the embodiment of the present invention is located. In addition to Figure 2 the shown processor, memory, network interface, and non-volatile memory, the electronic device where the device is located in the embodiment usually may also include other hardware, such as a forwarding chip responsible for processing packets, etc. Taking software implementation as an example, as Figure 3 shown, as a logically meaningful device, it is formed by the CPU of its corresponding electronic device reading the computer program in the non-volatile memory into the memory and running.

[0080] As Figure 3As shown in the figure, an autonomous management device for on-board time of a satellite cluster provided in this embodiment includes:

[0081] An acquisition unit 301, configured to acquire the time of the central management unit; wherein, the time of the central management unit is the on-board time of the main satellite;

[0082] A first correction unit 302, configured to correct the on-board time of the main satellite according to the time of the central management unit, the time generated by the GNSS system, and the ground time;

[0083] A second correction unit 303, configured to correct the time of the inter-satellite link processor by using the corrected on-board time of the main satellite and the ground time;

[0084] A third correction unit 304, configured to correct the on-board time of the slave satellite according to the corrected on-board time of the main satellite, the corrected time of the inter-satellite link processor, and the ground time, so as to realize the autonomous management of the on-board time of the satellite cluster.

[0085] In the embodiment, the acquisition unit 301 can be used to execute step 100 in the above method embodiment, the first correction unit 302 can be used to execute step 102 in the above method embodiment, the second correction unit 303 can be used to execute step 104 in the above method embodiment, and the third correction unit 304 can be used to execute step 106 in the above method embodiment.

[0086] In an embodiment of the present invention, the first correction unit 302 is configured to perform the following operations:

[0087] S1. Calculate the time sent from the central management unit to the GNSS system according to the time of the central management unit and the first initial time delay error;

[0088] S2. Calculate the satellite-ground time difference according to the time sent from the central management unit to the GNSS system and the time generated by the CNSS system;

[0089] S3. Determine whether the satellite-ground time difference exceeds a preset range. If so, determine the sum of the satellite-ground time difference and the time of the central management unit as the current on-board time of the main satellite;

[0090] S4. If not, determine the time of the central management unit as the current on-board time of the main satellite;

[0091] S5. Calculate the current first time delay error according to the current on-board time of the main satellite and the ground time, and use this first time delay error as the first initial time delay error to repeat steps S1 to S4 until the on-board time of the main satellite meets the preset requirements, so as to complete the correction of the on-board time of the main satellite.

[0092] In an embodiment of the present invention, the time sent by the central management unit to the GNSS system is calculated by the following formula:

[0093] t = t sat + △t0

[0094] where t is the time sent by the central management unit to the GNSS system, t sat is the time of the central management unit, and △t0 is the first initial time delay error.

[0095] In an embodiment of the present invention, the space - to - ground time difference is calculated by the following formula:

[0096] △t = t GNSS - t

[0097] where △t is the space - to - ground time difference, t GNSS is the time generated by the GNSS system, and t is the time sent by the central management unit to the GNSS system.

[0098] In an embodiment of the present invention, in the first correction unit 302:

[0099] Obtain the satellite time and ground time of the main satellite at multiple time measurement points through the telemetry system;

[0100] Calculate the first space - to - ground time difference at each time measurement point according to the difference between the satellite time and the ground time of the main satellite at each time measurement point;

[0101] Determine the average value of the first space - to - ground time differences at multiple time measurement points as the current first time delay error.

[0102] In an embodiment of the present invention, the second correction unit 303 is used to perform the following operations:

[0103] Calculate the time for the central management unit to time - transfer to the inter - satellite link processor according to the satellite time of the corrected main satellite and the second initial time delay error;

[0104] Determine the time of the time - transfer as the current time of the inter - satellite link processor;

[0105] Calculate the current second time delay error according to the current time of the inter - satellite link processor and the ground time, and use this second time delay error as the second initial time delay error to repeat the calculation step of the time - transfer time and the determination step of the time of the inter - satellite link processor until the time of the inter - satellite link processor meets the preset requirements to complete the correction of the time of the inter - satellite link processor.

[0106] In an embodiment of the present invention, in the second correction unit 303,

[0107] Obtain the time of the inter-satellite link processor and the ground time at multiple time measurement points through the telemetry system;

[0108] According to the difference between the time of the inter-satellite link processor and the ground time at each time measurement point, calculate the second satellite-ground time difference at each time measurement point respectively;

[0109] Determine the average value of the second satellite-ground time differences at multiple time measurement points as the current second time delay error.

[0110] In an embodiment of the present invention, in the third correction unit 304,

[0111] Calculate the time when the master satellite transmits time to the slave satellite through the inter-satellite link processor according to the satellite time of the master satellite after correction and the third initial time delay error;

[0112] Determine the time when the slave satellite is time-transmitted as the current satellite time of the slave satellite;

[0113] According to the satellite time and the ground time of the current slave satellite, calculate the current third time delay error, and use this third time delay error as the third initial time delay error to repeat the calculation step of the time when the slave satellite is time-transmitted and the determination step of the satellite time of the slave satellite until the satellite time of the slave satellite meets the preset requirements, so as to complete the correction of the satellite time of the slave satellite.

[0114] In an embodiment of the present invention, in the third correction unit 304,

[0115] Obtain the time of the slave satellite and the ground time at multiple time measurement points through the ground measurement and control station;

[0116] According to the difference between the time of the slave satellite and the ground time at each time measurement point, calculate the third satellite-ground time difference at each time measurement point respectively;

[0117] Determine the average value of the third satellite-ground time differences at multiple time measurement points as the current third time delay error.

[0118] It can be understood that the structure schematically shown in the embodiments of the present invention does not constitute a specific limitation on an on-satellite time autonomous management device for a satellite cluster. In other embodiments of the present invention, an on-satellite time autonomous management device for a satellite cluster may include more or fewer components than those shown in the figure, or combine certain components, or split certain components, or have different component arrangements. The components shown in the figure can be implemented in hardware, software, or a combination of software and hardware.

[0119] Regarding the information interaction, execution process, etc. between the various modules in the above device, since they are based on the same concept as the method embodiments of the present invention, the specific content can be referred to the description in the method embodiments of the present invention, and will not be elaborated here.

[0120] An embodiment of the present invention further provides an electronic device, including a memory and a processor. A computer program is stored in the memory. When the processor executes the computer program, an autonomous management method for on-board time of a satellite cluster in any embodiment of the present invention is implemented.

[0121] An embodiment of the present invention further provides a computer-readable storage medium. A computer program is stored on the computer-readable storage medium. When the computer program is executed by a processor, the processor is caused to execute an autonomous management method for on-board time of a satellite cluster in any embodiment of the present invention.

[0122] Specifically, a system or device equipped with a storage medium can be provided. A software program code for implementing the functions in any one of the above embodiments is stored on the storage medium, and the computer (or CPU or MPU) of the system or device reads and executes the program code stored in the storage medium.

[0123] In this case, the program code read from the storage medium itself can implement the functions in any one of the above embodiments. Therefore, the program code and the storage medium storing the program code constitute a part of the present invention.

[0124] Embodiments of the storage medium for providing the program code include floppy disks, hard disks, magneto-optical disks, optical disks (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), magnetic tapes, non-volatile memory cards, and ROMs. Optionally, the program code can be downloaded from a server computer via a communication network.

[0125] In addition, it should be clear that not only can the functions in any one of the above embodiments be implemented by executing the program code read by the computer, but also by causing an operating system or the like operating on the computer based on the instructions of the program code to complete part or all of the actual operations.

[0126] In addition, it can be understood that the program code read from the storage medium is written into the memory provided in the expansion board inserted into the computer or the memory provided in the expansion module connected to the computer, and then based on the instructions of the program code, the CPU or the like installed on the expansion board or the expansion module is caused to execute part and all of the actual operations, thereby implementing the functions in any one of the above embodiments.

[0127] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising said element.

[0128] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An autonomous management method for on-board time of a satellite cluster, characterized in that, Including: Obtaining the time of the central management unit; wherein, the time of the central management unit is the satellite time of the main satellite; Calibrating the satellite time of the main satellite according to the time of the central management unit, the time generated by the GNSS system, and the ground time, including: S1. Calculating the time sent from the central management unit to the GNSS system according to the time of the central management unit and the first initial time-delay error; S2. Calculating the satellite-ground time difference according to the time sent from the central management unit to the GNSS system and the time generated by the CNSS system; S3. Judging whether the satellite-ground time difference exceeds the preset range. If so, determining the sum of the satellite-ground time difference and the time of the central management unit as the current satellite time of the main satellite; S4. If not, determining the time of the central management unit as the current satellite time of the main satellite; S5. Calculating the current first time-delay error according to the current satellite time of the main satellite and the ground time, and using this first time-delay error as the first initial time-delay error to repeat steps S1 to S4 until the satellite time of the main satellite meets the preset requirements to complete the calibration of the satellite time of the main satellite; Calibrating the time of the inter-satellite link processor by using the calibrated satellite time of the main satellite and the ground time, including: Calculating the time for the central management unit to time the inter-satellite link processor according to the calibrated satellite time of the main satellite and the second initial time-delay error; Determining the timing time as the current time of the inter-satellite link processor; Calculating the current second time-delay error according to the current time of the inter-satellite link processor and the ground time, and using this second time-delay error as the second initial time-delay error to repeat the calculation step of the timing time and the determination step of the time of the inter-satellite link processor until the time of the inter-satellite link processor meets the preset requirements to complete the calibration of the time of the inter-satellite link processor; Calibrating the satellite time of the slave satellite according to the calibrated satellite time of the main satellite, the calibrated time of the inter-satellite link processor, and the ground time to realize the autonomous management of the on-board time of the satellite cluster.

2. The method according to claim 1, wherein The time sent from the central management unit to the GNSS system is calculated by the following formula: t = t sat + Δt0 where t is the time sent from the central management unit to the GNSS system, t sat is the time of the central management unit, and △t0 is the first initial delay error; and / or The satellite-ground time difference is calculated by the following formula: △t = t GNSS -t where Δt is the time difference between the satellite and the ground, t GNSS is the time generated by the GNSS system, and t is the time sent from the central management unit to the GNSS system.

3. The method according to claim 1, wherein Calculating the current first time-delay error according to the current satellite time of the main satellite and the ground time includes: Obtaining the satellite time of the main satellite and the ground time at multiple time measurement points through the telemetry system; Calculating the first satellite-ground time difference at each time measurement point respectively according to the difference between the satellite time of the main satellite and the ground time at each time measurement point; Determining the average value of the first satellite-ground time differences at multiple time measurement points as the current first time-delay error.

4. The method according to claim 1, characterized in that Calculating the current second time-delay error according to the current time of the inter-satellite link processor and the ground time includes: Obtaining the time of the inter-satellite link processor and the ground time at multiple time measurement points through the telemetry system; Calculating the second satellite-ground time difference at each time measurement point respectively according to the difference between the time of the inter-satellite link processor and the ground time at each time measurement point; Determining the average value of the second satellite-ground time differences at multiple time measurement points as the current second time-delay error.

5. The method according to claim 1, wherein Calibrating the satellite time of the slave satellite according to the calibrated satellite time of the main satellite, the calibrated time of the inter-satellite link processor, and the ground time includes: Calculate the time when the master satellite transmits time to the slave satellite through the inter-satellite link processor according to the star time of the master satellite after calibration and the third initial time delay error; Determine the time when the slave satellite is time-synchronized as the current star time of the slave satellite; Calculate the current third time delay error according to the star time of the current slave satellite and the ground time, and use this third time delay error as the third initial time delay error to repeatedly execute the calculation step of the time when the slave satellite is time-synchronized and the determination step of the star time of the slave satellite until the star time of the slave satellite meets the preset requirements to complete the calibration of the star time of the slave satellite; and / or Obtain the slave satellite time and ground time at multiple time measurement points through the ground TT&C station; Calculate the third satellite-ground time difference at each time measurement point according to the difference between the slave satellite time and the ground time at each time measurement point; Determine the average value of the third satellite-ground time differences at multiple time measurement points as the current third time delay error.

6. An on-satellite time autonomous management device for a satellite cluster, which is used to implement the method described in any one of claims 1 to 5, and is characterized in that, Comprising: An acquisition unit for acquiring the time of the central management unit; wherein, the time of the central management unit is the star time of the master satellite; A first calibration unit for calibrating the star time of the master satellite according to the time of the central management unit, the time generated by the GNSS system, and the ground time; A second calibration unit for calibrating the time of the inter-satellite link processor by using the star time of the master satellite after calibration and the ground time; A third calibration unit for calibrating the star time of the slave satellite according to the star time of the master satellite after calibration, the time of the inter-satellite link processor after calibration, and the ground time to realize the autonomous management of the on-board time of the satellite cluster.

7. An electronic device, comprising a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the method according to any one of claims 1-5 is implemented.

8. A computer-readable storage medium, on which a computer program is stored, and when the computer program is executed in a computer, the computer is made to execute the method according to any one of claims 1-5.

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