Research And Implementation Of Remote Timing Synchronization Technology

With the continuous advancement of science and technology,the exchange between globalization has become more and more frequent,and higher and higher requirements have been placed on the accuracy of remote time synchronization.Nowadays,the long-distance time synchronization methods used to realize the world mainly include wired communication,wireless communication,and satellite communication.At present,with the development of society,the requirements for timing accuracy are getting higher and higher,and traditional timing methods have been difficult to meet the requirements of various parties.Because of its good real-time performance and high timing accuracy,the two-way time comparison system has been widely used this year,and the technology has become more and more mature.This paper is based on the bidirectional time comparison algorithm basis,designing and completing the QPSK communication link.Based on the QPSK communication link,the FPGA program model of the bidirectional time synchronization system is established.This paper first introduces the algorithm principle of the bidirectional time alignment algorithm,and establishes a mathematical model to elaborate its algorithm principle.Then specifically expounded the design of the bidirectional time comparison system,including the design of the overall system,the time frame design of the central station and the external station,the logic design of the framing,and the discussion of the time synchronization interval.The following article describes the principles and design points of the QPSK link,including design filtering,timing synchronization and carrier recovery,scrambling and descrambling,convolutional coding and differential coding,and focuses on the design of all-digital phase-locked loops.Principles and design points.Secondly,this paper completes the design and implementation of other modules on the basis of QPSK link,including time data processing module,framing module,and time compensation module.After implementing the entire bidirectional time synchronization system,a performance measurement was performed.The performance of the QPSK link was first detected,and how the loop was realized under the conditions of larger symbol frequency offset and carrier frequency deviation.Finally,the time synchronization effect of the bidirectional time comparison system is detected,and it takes how much time to lock the seconds pulse within 200 ns.