High-precision time correction method for spacecraft equipment

Abstract

The invention discloses a high-precision time calibration method for spacecraft equipment, which comprises the following steps: step 1, after equipment needing high-precision time service is powered on and runs, the equipment performs accumulated self-punctuality according to an initial moment and an internal crystal oscillator, and updates whole-second time information and intra-second time information of maintenance time of the equipment; 2, the time service upper computer sends ETR second pulse signals strictly aligned with the whole second moment and whole second time information of the time code of the current second to the equipment in a fixed period per second; and step 3, the equipment completes local time updating according to the ETR pulse per second signal sent by the time service upper computer and the whole second time information of the current beat time code, and keeps synchronization with the time of the time service upper computer. The method is easy to implement, can overcome the defect that when a time service upper computer hard pulse ETR signal and time information serve as a time correction method in the prior art, time correction fails due to the fact that an upper computer signal breaks down, effectively reduces the risk of system function failure, and remarkably improves reliability and safety of spacecraft equipment time synchronization.

Description

Technical Field

[0001] This invention relates to the field of spaceborne equipment technology, and in particular to a high-precision time calibration method for spacecraft equipment. Background Technology

[0002] The existing technology 1 is a satellite time synchronization system, which includes a time transmission part, a time transmission part and a time receiving part. It achieves satellite time synchronization by calculating the precise time of the navigation signal output by the onboard navigation receiver and the navigation time synchronization method of the whole second pulse signal. However, it does not propose a time synchronization method and strategy for any specific device.

[0003] Existing technology 2 is a general time synchronization test device and method for automated time synchronization testing of cross-type spaceborne navigation receivers. It is mainly used for automated high-precision time synchronization testing, but does not propose a time synchronization method and strategy for any specific device.

[0004] Existing technology three is a high-precision GPS whole-second pulse time synchronizer for spacecraft. It uses hardware latching technology to replace the traditional software interrupt method to record the time of the pulse signal corresponding to the timer, which improves the accuracy and stability of time synchronization using GPS whole-second pulses. However, it does not propose a time synchronization method or strategy for any specific device.

[0005] The method provided by this invention is simple to implement and can overcome the shortcomings of traditional time synchronization methods that fail when the time synchronization host computer signal malfunctions. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies, this invention provides a high-precision time synchronization method for spacecraft equipment, which effectively reduces the risk of system malfunction and significantly improves the reliability and safety of time synchronization for spacecraft equipment.

[0007] To achieve the aforementioned objectives of the invention, the technical solution adopted to solve its technical problems is as follows: A high-precision time calibration method for spacecraft equipment includes the following steps: Step 1: After the equipment is powered on and running, the equipment accumulates self-keeping time based on the initial time and the internal crystal oscillator, and completes the update of the whole second time information and the time information within the second of the equipment's own maintenance time; Step 2: The timing host computer sends an ETR second pulse signal and the current time code integer second information to the device once per second at a fixed period; Step 3: The device updates its local time based on the ETR second pulse signal sent by the time synchronization host computer and the current time code whole second time information, and keeps synchronized with the time of the time synchronization host computer.

[0008] Furthermore, in step 1, the high-precision time information for equipment maintenance includes whole-second information and time information within seconds, with the count within seconds accumulating to a whole second and then incrementing the whole-second information by 1.

[0009] Furthermore, in step 2, the time synchronization center, as a high-precision time reference source, typically uses a GPS or BD navigation receiver as the time reference source, and can output a second pulse signal that is strictly aligned with the whole second time as well as absolute time code information.

[0010] Step 3 includes the following: Step 31: When a time synchronization command containing whole second time information is received from the host computer, the whole second information is stored in the device's internal register, and the device continues to wait for the next ETR second pulse signal sent by the host computer. If multiple time synchronization commands are received during this period, the whole second information received in the latest command is updated in the register, and the process proceeds to step 32. Step 32: When the ETR second pulse signal sent by the timing host computer is received, the whole second time stored in the register last time is increased by 1 second as the current new maintenance whole second information for timekeeping. The second count is cleared and restarted, and the system continues to wait for the time code whole second time information sent by the timing host computer, and then proceeds to step 31. Steps 31 and 32 are not sequential; they are triggered in the order of the received times and are continuously repeated to update the time.

[0011] Furthermore, if the timing instruction for sending the time code whole second information from the timing host computer fails, but the ETR second pulse signal is normal, then at the arrival time of the ETR pulse, if it is detected that the whole second information was not stored in the device's internal register in the previous second, the count of the current maintenance time within seconds is determined. Based on whether the current count of the second within seconds is greater than 0.5 seconds, it is determined whether to add 1 second to the current whole second moment of maintenance.

[0012] Furthermore, when the device receives the ETR second pulse and the local maintenance time count within seconds is greater than 0.5 seconds, the current maintenance time is incremented by 1 second, and the count within seconds is reset to zero and restarted. When the device receives the ETR second pulse, the local maintenance time count within seconds is less than 0.5 seconds. The current maintenance time in whole seconds remains unchanged, and the count within seconds is reset to zero and starts counting again.

[0013] Furthermore, if the timing instruction sent by the timing host computer is for whole second time information, but the ETR second pulse fails (i.e., the device does not receive the ETR second pulse sent by the timing host computer), then the operation of changing the whole second time in the device's internal register will not be changed. Instead, the device will accumulate and self-maintain time according to its internal clock to complete the time maintenance and update.

[0014] By employing the above technical solutions, this invention has the following advantages and positive effects compared with the prior art: In this invention, the spacecraft equipment receives a hard pulse ETR pulse signal and the current time code integer second information sent by a high-precision time synchronization host computer for time synchronization. The hard pulse ETR pulse signal sent by the host computer is strictly aligned with the host computer's integer second time. The integer second time code information sent by the host computer arrives later than the ETR second pulse due to communication delay. The equipment's own maintenance time includes integer second counting and intra-second counting. Receiving the hard pulse ETR pulse signal is used to align the equipment's and the host computer's integer second times, while receiving the integer second time code is used to maintain time synchronization with the host computer's time information.

[0015] This invention provides a high-precision time synchronization method for spacecraft equipment. It comprehensively considers the time synchronization and maintenance of the equipment's own time system when the second pulse signal and time code information from the host computer are valid or invalid, effectively ensuring the accuracy of the equipment's own maintenance time. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 This is a flowchart illustrating a high-precision time calibration method for spacecraft equipment according to the present invention. Detailed Implementation

[0017] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] like Figure 1 As shown, this embodiment discloses a high-precision time calibration method for spacecraft equipment, including the following steps: Step 1: After the equipment is powered on and running, the equipment accumulates self-keeping time based on the initial time and the internal crystal oscillator, and completes the update of the whole second time information and the time information within the second of the equipment's own maintenance time. At this time, no time information has been received yet. Step 2: The timing host computer sends an ETR second pulse signal (ETR1, ETR2, ETR3, ...) and the current capture time code integer second time information (T0, T1, T2, ...) to the device once per second at a fixed period. Step 3: The device updates its local time based on the ETR second pulse signal sent by the time synchronization host computer and the current time code whole second time information, and keeps synchronized with the time of the time synchronization host computer.

[0019] Furthermore, step 3 includes the following: Step 31: When a time synchronization instruction containing the whole second time information T0 is received from the time synchronization host computer, the whole second information T0 is stored in the device's internal register, and the device continues to wait for the next ETR second pulse signal; if multiple time synchronization instructions are received during this period, the whole second information received in the latest instruction is updated in the register, and the process proceeds to step 32. Step 32: When the ETR second pulse signal sent by the timing host computer is received, the whole second time stored in the register last time is added by 1 second as the current new maintenance whole second information, i.e., T0+1s, for timekeeping. The second count is cleared and recounted, and the system continues to wait for the time code whole second time information sent by the timing host computer, and then proceeds to step 31. Steps 31 and 32 are not sequential; they are triggered in the order of the received times and are continuously repeated to complete the update of the local maintenance time.

[0020] In step 3, if the timing instruction for sending the time code whole second time information sent by the timing host computer fails, but the ETR second pulse signal is normal, then at the time the ETR pulse arrives, if it is detected that the whole second information was not stored in the device's internal register in the previous second, then the count of the current maintenance time within seconds is determined. Based on whether the current count of the second is greater than 0.5 seconds, it is determined whether to add 1 second to the current maintenance whole second time.

[0021] Furthermore, when the device receives the ETR second pulse and the local maintenance time count within seconds is greater than 0.5 seconds, the current maintenance time is incremented by 1 second, and the count within seconds is reset to zero and restarted. When the device receives the ETR second pulse, the local maintenance time count within seconds is less than 0.5 seconds. The current maintenance time in whole seconds remains unchanged, and the count within seconds is reset to zero and starts counting again.

[0022] In step 3, if the timing instruction for the whole second time information sent by the timing host computer fails due to an ETR second pulse failure (i.e., the device does not receive the ETR second pulse sent by the timing host computer), the operation of not changing the whole second time in the device's internal register will not be performed. Instead, the device will accumulate and self-maintain time according to its internal clock to complete the time maintenance and update.

[0023] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A high-precision time calibration method for spacecraft equipment, characterized in that, Includes the following steps: Step 1: After the equipment requiring high-precision time synchronization is powered on and running, the equipment accumulates its own time based on the initial time and the internal crystal oscillator, and completes the update of the whole second time information and the time information within the second of the equipment's own maintenance time; Step 2: The timing host computer sends an ETR second pulse signal, which is strictly aligned with the whole second, and the current time code whole second time information to the device once per second at a fixed period; Step 3: The device updates its local time based on the ETR second pulse signal sent by the time synchronization host computer and the current time code whole second time information, and keeps synchronized with the time of the time synchronization host computer.

2. The high-precision time calibration method for spacecraft equipment according to claim 1, characterized in that, In step 1, the high-precision time information for equipment maintenance includes whole-second information and time information within seconds, with the count within seconds accumulating to a whole second, and the whole-second information is incremented by 1.

3. The high-precision time calibration method for spacecraft equipment according to claim 1, characterized in that, In step 2, the time center serves as a high-precision time reference source, typically using a GPS or BD navigation receiver as the time reference source. It can output second pulse signals that are strictly aligned with whole-second times and absolute time code information.

4. The high-precision time calibration method for spacecraft equipment according to claim 1, characterized in that, Step 3 includes the following: Step 31: When a time synchronization command containing whole second time information is received from the host computer, the whole second information is stored in the device's internal register, and the device continues to wait for the next ETR second pulse signal sent by the host computer. If multiple time synchronization commands are received during this period, the whole second information received from the latest command is updated in the register, and the process proceeds to step 32. Step 32: When the ETR second pulse signal sent by the timing host computer is received, the whole second time stored in the register last time is increased by 1 second as the current new maintenance whole second information for timekeeping. The second count is cleared and restarted, and the system continues to wait for the time code whole second time information sent by the timing host computer, and then proceeds to step 31. Steps 31 and 32 are not sequential; they are triggered in the order of the received times and are continuously repeated to update the time.

5. The high-precision time calibration method for spacecraft equipment according to claim 4, characterized in that, If the timing instruction for sending the time code to the host computer is faulty, but the ETR second pulse signal is normal, then at the arrival time of the ETR pulse, if it is detected that the previous second did not perform the operation of storing the whole second information into the device's internal register, then the count of the current maintenance time within seconds is determined. Based on whether the current count of the second within seconds is greater than 0.5 seconds, it is determined whether to add 1 second to the current maintenance time.

6. The high-precision time calibration method for spacecraft equipment according to claim 5, characterized in that, When the device receives the ETR second pulse and the local maintenance time count within seconds is greater than 0.5 seconds, the current maintenance time is incremented by 1 second, and the count within seconds is reset to zero and restarted. When the device receives the ETR second pulse, the local maintenance time count within seconds is less than 0.5 seconds. The current maintenance time in whole seconds remains unchanged, and the count within seconds is reset to zero and starts counting again.

7. A high-precision time calibration method for spacecraft equipment according to claim 6, characterized in that, If the timing instruction sent by the host computer is for whole-second time information, but the ETR second pulse fails (i.e., the device does not receive the ETR second pulse sent by the host computer), then the device will not change the whole-second time in its internal register. Instead, the device will accumulate and self-regulate the time according to its internal clock to complete the time maintenance and update.

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