Design And Implementation Of Intelligent Control And Monitoring Module In Optical Fiber Time Synchronization System

The demand for high precision time signals in critical areas such as modern communication devices and transportation systems is increasing.Using fiber optic as a transmission medium is an important way to achieve high-precision time synchronization due to its high speed,large bandwidth,low loss,and interference resistance.The commonly used methods for fiber optic time synchronization are round-trip method and two-way comparison.The round-trip method is simple to implement and only requires transmitting round-trip signals in the same fiber.By measuring the loop delay and compensating for the transmission signal delay,the stability of time synchronization can be ensured.The two-way comparison method can reduce the time error caused by external factors and improve the accuracy and reliability of time synchronization.A stable control monitoring module is required for the fiber optic time synchronization system to perform long-term real-time comparisons.For the above situation,this paper designs and implements an intelligent control monitoring module for the fiber time synchronization system.This module completes the algorithm part of the round-trip method and the two-way comparison method in the fiber time synchronization system.An adaptive Kalman filtering time synchronization optimization algorithm is proposed to improve the stability of time synchronization.The specific contents of the paper are as follows:(1)An intelligent control monitoring module was designed and implemented for the fiber time synchronization system,consisting of an instrument interaction program responsible for instrument data acquisition and transmission;A server program was developed for remote data transmission with features such as real-time data display,anomaly warning,and display of machine room temperature records.;The main program for time synchronization was developed,which ultimately achieved the twoway comparison algorithm and the round-trip algorithm.After completing all module designs,software functionality testing was carried out,and experimental verification was performed using the two methods under 1000km laboratory fiber link conditions,successfully achieving local and remote time synchronization.(2)The intelligent control monitoring module was optimized using the adaptive Kalman filtering algorithm.Under the same experimental conditions mentioned above,investigations were conducted on the twoway comparison algorithm and the round-trip algorithm.Traditional Kalman filtering algorithm was used to filter the adjustment quantity,and the filtering effect of the algorithm was observed for different parameters.The experiments showed that the filtering effect was greatly affected by different parameters.When using the two-way comparison method,the standard deviation of the time difference was 49ps,and when using the round-trip method,the standard deviation of the time difference was 92ps.In order to address the issue of poor filtering effect due to fixed parameters in traditional Kalman filtering,an adaptive Kalman filtering algorithm was introduced for experiments,and the effectiveness of this algorithm was observed under the same initial parameter values.The results showed that the adaptive Kalman filtering algorithm could effectively improve the stability of time synchronization under different initial parameter values.When using the two-way comparison method,the standard deviation of the time difference was 47ps,and when using the round-trip method,the standard deviation of the time difference was 86ps.In summary,this paper has completed the intelligent control and monitoring module in the fiber time synchronization system and successfully operated it stably under the laboratory fiber link conditions of 1000 km.The paper introduced the adaptive Kalman filtering algorithm for the time synchronization system,further improving the system’s antiinterference ability and stability.