Method for realizing synchronization of local clock and system clock based on Beidou time service

Abstract

The invention discloses a method for realizing synchronization of a local clock and a system clock based on Beidou time service, which comprises the following steps that: a Beidou terminal receives a Beidou time service signal, packages time information into a data packet through a preset communication protocol and an interface, and adds a check code and a timestamp; errors and interferences in a data transmission process are processed by adopting error correction coding and digital filtering technologies, so that the data transmission reliability is improved; according to a network topology structure and link quality, an optimal transmission route is dynamically selected, and a multi-path transmission and load balancing technology is adopted, so that the transmission efficiency is improved; the receiving end reorganizes and verifies the received time information data packet, extracts time information and converts the time information into a standard time format; the method comprises the following steps: receiving Beidou time service signals for multiple times, calculating transmission delay and clock skew by utilizing a least square method, and dynamically adjusting local clock parameters by adopting a proportional integral control algorithm and a Kalman filtering algorithm to realize nanosecond time synchronization.

Description

Technical Field

[0001] The present invention relates to the field of information technology, and in particular to a method for realizing synchronization between a local clock and a system clock based on Beidou timing. Background Art

[0002] There are many delay factors in the transmission of Beidou timing signals, including ionospheric delay, tropospheric delay, multipath effect, satellite clock error, receiver clock error, relativistic effect, hardware delay and signal strength attenuation. These delay factors will cause the received timing signal to deviate from the actual time, affecting the accuracy of time synchronization. In order to achieve high-precision time synchronization, these delay factors need to be accurately estimated and compensated.

[0003] However, due to the complexity and dynamic characteristics of various delay factors, it is difficult to directly calculate and compensate for each delay factor. Therefore, the least squares method is used to fit and calculate multiple sets of clock deviation sample data, which becomes an effective solution. However, in practical applications, how to reasonably establish observation equations, set weight matrices, handle outliers, and how to combine fitting results with real-time dynamic adjustment of local clock parameters have become key technical issues that need to be solved. At the same time, how to achieve dynamic compensation and continuous optimization of various transmission delay factors while maintaining high-precision synchronization is also a challenge that needs to be solved urgently. Summary of the invention

[0004] The present invention provides a method for realizing synchronization between a local clock and a system clock based on Beidou timing, which mainly includes:

[0005] The Beidou terminal receives Beidou timing signals, and encapsulates the time information into data packets through preset communication protocols and interfaces, and adds checksums and timestamps. Error correction coding and digital filtering technology are used to deal with errors and interference in the data transmission process to improve data transmission reliability. The optimal transmission route is dynamically selected based on the network topology and link quality, and multi-path transmission and load balancing technology are used to improve transmission efficiency. The receiving end reorganizes and verifies the received time information data packets, extracts the time information and converts it into a standard time format. By receiving Beidou timing signals multiple times, the transmission delay and clock deviation are calculated using the least squares method, and the proportional-integral control algorithm and Kalman filtering algorithm are used to dynamically adjust the local clock parameters to achieve nanosecond time synchronization.

[0006] Furthermore, the processing using error correction coding and digital filtering technology includes: if a data error is detected, requesting retransmission or performing data repair; if interference is detected, adjusting the data transmission frequency or increasing the signal power.

[0007] Furthermore, the dynamic selection of the best transmission route includes: regularly detecting the network status, obtaining parameters such as delay and bandwidth of each node, building a network performance model, and predicting transmission delay and packet loss rate.

[0008] Furthermore, the multi-path transmission and load balancing technology includes: dividing the time information into multiple data blocks and transmitting them in parallel; and dynamically adjusting the data transmission rate through a congestion control algorithm to avoid network congestion.

[0009] Furthermore, the extracting of time information and converting it into a standard time format includes: judging whether the data is complete and accurate by comparing the timestamp and checksum of the data packet; if the data is correct, extracting the time information and converting it into a standard time format.

[0010] Furthermore, the use of least squares method to calculate the transmission delay and clock deviation includes: calculating the transmission delay factors such as ionospheric delay, tropospheric delay, multipath effect, satellite clock error, receiver clock error, relativistic effect, hardware delay and signal strength attenuation according to the received Beidou timing signal, and obtaining the initial clock deviation value.

[0011] Furthermore, the method of calculating the transmission delay and clock deviation using the least squares method also includes: performing fitting calculations on multiple groups of clock deviation sample data, establishing observation equations and setting weight matrices, and solving normal equations to obtain time deviation estimates; performing parameter significance tests and goodness of fit evaluations on the fitting results through residual calculations and variance-covariance matrix estimation, eliminating outliers and optimizing the fitting model.

[0012] Furthermore, the proportional-integral control algorithm and the Kalman filter algorithm are used to dynamically adjust the local clock parameters, including: according to the optimized time deviation estimate, the proportional-integral control algorithm is used to dynamically adjust the frequency and phase parameters of the local clock to compensate for various transmission delay factors; and the deviation between the local clock and the Beidou timing signal is recalculated using the adjusted clock parameters to determine whether the nanosecond synchronization accuracy requirement is met.

[0013] Furthermore, the use of proportional-integral control algorithm and Kalman filtering algorithm to dynamically adjust local clock parameters also includes: if the synchronization accuracy requirement is not met, repeatedly executing fitting calculation processes such as observation equation establishment, weight matrix setting, and normal equation solving until the local clock and Beidou timing signal are synchronized with high precision.

[0014] Furthermore, the implementation of nanosecond time synchronization also includes: calculating a precise clock offset based on the synchronized local clock to compensate for transmission delay factors such as ionospheric delay and tropospheric delay; by continuously monitoring the deviation between the Beidou timing signal and the local clock, dynamically adjusting fitting parameters such as the observation equation and weight matrix to maintain a nanosecond high-precision time synchronization state.

[0015] The technical solution provided by the embodiment of the present invention may have the following beneficial effects:

[0016] The present invention provides a method for realizing synchronization between a local clock and a system clock based on Beidou timing. By receiving Beidou timing signals, a preset communication protocol is adopted to encapsulate time information into a data packet and add a check code and a timestamp. Error correction coding and digital filtering technology are adopted to process errors and interferences in the transmission process. In order to optimize the transmission path, the best route is dynamically selected according to the network topology structure, and multi-path transmission and load balancing technology are adopted to improve efficiency. The check data packet is reorganized at the receiving end, and the time information is extracted and converted into a standard format. By calculating the transmission delay and clock deviation, the local clock parameters are dynamically adjusted by using a proportional integral control algorithm. The least square method is used to fit multiple groups of clock deviation samples, establish an observation equation and solve the normal equation to obtain a time deviation estimate. Various delay factors are compensated according to the estimated value to achieve nanosecond-level high-precision time synchronization. The present invention can effectively solve the error accumulation problem in the Beidou timing signal transmission and local clock synchronization process, and significantly improve the time synchronization accuracy and stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The present invention is a flow chart of realizing synchronization between a local clock and a system clock based on Beidou timing.

[0018] Figure 2 It is a schematic diagram of realizing synchronization between a local clock and a system clock based on Beidou timing according to the present invention.

[0019] Figure 3 It is another schematic diagram of realizing synchronization between a local clock and a system clock based on Beidou timing according to the present invention.

[0020] Figure 4 It is another schematic diagram of realizing synchronization between a local clock and a system clock based on Beidou timing according to the present invention.

[0021] Figure 5 It is another schematic diagram of realizing synchronization between a local clock and a system clock based on Beidou timing according to the present invention.

[0022] Figure 6 It is another schematic diagram of realizing synchronization between a local clock and a system clock based on Beidou timing according to the present invention.

[0023] Figure 7 It is another schematic diagram of realizing synchronization between a local clock and a system clock based on Beidou timing according to the present invention.

[0024] Figure 8 It is another schematic diagram of realizing synchronization between a local clock and a system clock based on Beidou timing according to the present invention.

[0025] Fig. 9 It is another schematic diagram of realizing synchronization between a local clock and a system clock based on Beidou timing according to the present invention.

[0026] Fig.10 It is another schematic diagram of realizing synchronization between a local clock and a system clock based on Beidou timing according to the present invention.

[0027] Fig.11 It is another schematic diagram of realizing synchronization between a local clock and a system clock based on Beidou timing according to the present invention. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below in conjunction with the drawings in the embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this specification, not all of the embodiments. Based on the embodiments in this specification, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this specification.

[0029] like Figure 1-Figure 11 As shown, the embodiment of realizing synchronization between the local clock and the system clock based on Beidou timing may specifically include:

[0030] S101. After receiving the Beidou timing signal, the Beidou terminal encapsulates the time information into a data packet through a preset communication protocol and communication interface, and adds a checksum and timestamp to ensure the integrity and real-time nature of the data.

[0031] S102: Error correction coding and digital filtering are used to improve the reliability of data transmission in response to possible errors and interferences during data transmission. If a data error is detected, a retransmission or data repair is requested; if interference is detected, the data transmission frequency is adjusted or the signal power is increased.

[0032] S103. In order to optimize the data transmission path, the best transmission route is dynamically selected according to the network topology and link quality. By regularly detecting the network status, the delay, bandwidth and other parameters of each node are obtained, and a network performance model is constructed to predict the transmission delay and packet loss rate.

[0033] S104. Based on the network performance model, multi-path transmission and load balancing technology are used to divide the time information into multiple data blocks for parallel transmission to improve transmission efficiency and reliability. At the same time, the data transmission rate is dynamically adjusted through the congestion control algorithm to avoid network congestion.

[0034] S105, at the receiving end, the received time information data packet is reorganized and verified, and the data is judged to be complete and accurate by comparing the timestamp and the verification code of the data packet. If the data is correct, the time information is extracted and converted into a standard time format.

[0035] S106: In order to synchronize the local clock with the system clock, it is necessary to calculate the transmission delay of the Beidou timing signal and the deviation of the local clock. The transmission delay and clock deviation are calculated by receiving the Beidou timing signal multiple times, recording the receiving timestamp, and using the least squares method to fit.

[0036] S107. According to the calculated transmission delay and clock deviation, adjust the time and frequency of the local clock to synchronize it with the Beidou system time. Use the proportional integral control algorithm to dynamically adjust the clock parameters, gradually reduce the synchronization error, and finally achieve nanosecond-level synchronization accuracy. At the same time, use the Kalman filter algorithm to filter out clock noise and interference and improve synchronization stability.

[0037] S108. According to the received Beidou timing signal, calculate the transmission delay factors such as ionospheric delay, tropospheric delay, multipath effect, satellite clock error, receiver clock error, relativistic effect, hardware delay and signal strength attenuation to obtain the initial clock deviation value.

[0038] S109, using the least square method to perform fitting calculations on multiple groups of clock deviation sample data, establishing an observation equation and setting a weight matrix, and solving the normal equation to obtain a time deviation estimate.

[0039] S1010. Perform parameter significance test and goodness of fit evaluation on the fitting results through residual calculation and variance-covariance matrix estimation, remove outliers and optimize the fitting model.

[0040] S1011. Based on the optimized time deviation estimate, a proportional-integral control algorithm is used to dynamically adjust the frequency and phase parameters of the local clock to compensate for various transmission delay factors.

[0041] S1012. Recalculate the deviation between the local clock and the Beidou timing signal using the adjusted clock parameters to determine whether the nanosecond synchronization accuracy requirement is met.

[0042] S1013. If the synchronization accuracy requirement is not met, the fitting calculation processes such as observation equation establishment, weight matrix setting, and normal equation solution are repeated until the local clock and the Beidou timing signal are synchronized with high precision.

[0043] S1014. Calculate an accurate clock offset based on the synchronized local clock to compensate for transmission delay factors such as ionospheric delay and tropospheric delay.

[0044] S1015. By continuously monitoring the deviation between the Beidou timing signal and the local clock, the fitting parameters such as the observation equation and weight matrix are dynamically adjusted to maintain a high-precision time synchronization state at the nanosecond level.

[0045] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for synchronizing a local clock with a system clock based on Beidou timing, characterized in that: include: The Beidou terminal receives the Beidou timing signal, and encapsulates the time information into a data packet through the preset communication protocol and interface, adding a checksum and timestamp; Error correction coding and digital filtering technology are used to deal with errors and interference during data transmission to improve data transmission reliability; Dynamically select the best transmission route based on network topology and link quality, and use multi-path transmission and load balancing technology to improve transmission efficiency; The receiving end reassembles and verifies the received time information data packets, extracts the time information and converts it into a standard time format; By receiving Beidou timing signals multiple times, the least squares method is used to calculate the transmission delay and clock deviation, and the proportional integral control algorithm and Kalman filter algorithm are used to dynamically adjust the local clock parameters to achieve nanosecond time synchronization.

2. The method for realizing synchronization between a local clock and a system clock based on Beidou timing as claimed in claim 1, characterized in that: Processing using error correction coding and digital filtering techniques, including: If a data error is detected, a retransmission or data repair is requested; If interference is detected, the data transmission frequency is adjusted or the signal power is increased.

3. The method for realizing synchronization between a local clock and a system clock based on Beidou timing as claimed in claim 1, characterized in that: Dynamically select the best transmission route, including: By regularly detecting the network status, obtaining the delay, bandwidth and other parameters of each node, building a network performance model, and predicting the transmission delay and packet loss rate.

4. The method for realizing synchronization between a local clock and a system clock based on Beidou timing as claimed in claim 1, characterized in that: Adopt multi-path transmission and load balancing technology, including: Split the time information into multiple data blocks and transmit them in parallel; Through the congestion control algorithm, the data sending rate is dynamically adjusted to avoid network congestion.

5. The method for realizing synchronization between a local clock and a system clock based on Beidou timing as claimed in claim 1, characterized in that: Extract time information and convert to standard time formats, including: By comparing the timestamp and checksum of the data packet, determine whether the data is complete and accurate; If the data is correct, the time information is extracted and converted into a standard time format.

6. The method for realizing synchronization between a local clock and a system clock based on Beidou timing as claimed in claim 1, characterized in that: Calculate propagation delay and clock skew using the least squares method, including: According to the received Beidou timing signal, the transmission delay factors such as ionospheric delay, tropospheric delay, multipath effect, satellite clock error, receiver clock error, relativistic effect, hardware delay and signal strength attenuation are calculated to obtain the initial clock deviation value.

7. The method for synchronizing a local clock with a system clock based on Beidou timing as claimed in claim 6, characterized in that: Calculates propagation delay and clock skew using the least squares method, also includes: Perform fitting calculations on multiple groups of clock deviation sample data, establish observation equations and set weight matrices, and solve normal equations to obtain time deviation estimates; Through residual calculation and variance-covariance matrix estimation, the fitting results were tested for parameter significance and goodness of fit, outliers were removed and the fitting model was optimized.

8. The method for synchronizing a local clock with a system clock based on Beidou timing as claimed in claim 1, characterized in that: Proportional-integral control algorithm and Kalman filter algorithm are used to dynamically adjust local clock parameters, including: According to the optimized time deviation estimate, the proportional integral control algorithm is used to dynamically adjust the frequency and phase parameters of the local clock to compensate for various transmission delay factors; Use the adjusted clock parameters to recalculate the deviation between the local clock and the Beidou timing signal to determine whether the nanosecond synchronization accuracy requirement is met.

9. The method for synchronizing a local clock with a system clock based on Beidou timing as claimed in claim 8, characterized in that: Proportional-integral control algorithm and Kalman filter algorithm are used to dynamically adjust local clock parameters, including: If the synchronization accuracy requirement is not met, the fitting calculation process such as establishing the observation equation, setting the weight matrix, solving the normal equation, etc. is repeated until the local clock and the Beidou timing signal are synchronized with high precision.

10. The method for synchronizing a local clock with a system clock based on Beidou timing as claimed in claim 1, characterized in that: Achieve nanosecond time synchronization, also includes: Based on the synchronized local clock, the precise clock offset is calculated to compensate for transmission delay factors such as ionospheric delay and tropospheric delay. By continuously monitoring the deviation between the Beidou timing signal and the local clock, the fitting parameters such as the observation equation and weight matrix are dynamically adjusted to maintain a high-precision time synchronization state at the nanosecond level.

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