冲击波超压测试系统的时基高精度同步

Time Benchmark High Precision Synchronization Method for Shock Wave Overpressure Testing System

针对存储式冲击波超压测试系统时基不能高精度同步的问题,提出一种光纤触发与高精度算法结合的处理方法。利用光纤对不同装置同时发出触发信号,实现多个装置的同步触发;计数频率远大于测试装置的采样频率,对触发时刻和触发后第一个采样时刻之间的时间间隔进行计数;对相邻两个采样点之间进行插值处理,根据计数值N确定测试数据在时间轴上的位置,实现时基的高精度同步。该方法可使得测试系统在12 m布场距离处触发响应时间小于150 ns,测试系统的时间误差为30 ns,测试装置之间的同步误差为20 ns。该方法提高了测试系统的测量精度,可为冲击波传播规律的研究提供依据。

Aiming at the problem that the time benchmark of storage shock wave overpressure measurement system could not be synchronized with high precision,a processing method combining optical fiber trigger and high precision algorithm was proposed.The optical fiber is used to send trigger signals to different devices at the same time,realizing the synchronous trigger of multiple devices.The counting frequency was much larger than the sampling frequency of the test device,and the time interval between the trigger moment and the first sampling moment after the trigger was counted.Interpolation was carried out between two adjacent sampling moments,and the position of test data on the time axis was determined the calculated value N,achieving high-precision synchronization of time benchmark.This method could make the trigger response time of the test system less than 150 ns at 12 m field distance,the time error of the test system was 30 ns,and the synchronization error between the test devices was 20 ns,which improved the measurement accuracy of the test system and provided a basis for the study of shock wave propagation law.