基于广义互相关技术的马赫泽德振动检测系统

Mach-Zehnder vibration detection system based on generalized cross-correlation technology

针对马赫泽德干涉系统振动事件定位性能有待改进的问题,构建了双路马赫泽德振动检测系统,分析了时延估计振动定位原理,提出了用于双路探测信号时延估计的广义互相关算法,增加了信号频域分析的灵活性和可行性,通过数字滤波减小了系统的定位误差。实验结果表明,系统可以准确检测与定位施加在传感光纤上的方波信号、冲击信号及敲击信号,并在传感距离为940m长的光纤上实现了小于20m的定位误差和可重复的稳定检测。从而为光纤振动传感技术在矿业与工业等领域的推广应用提供了一种新的解决思路。

In view of the problem that the positioning performance of the Mach-Zehnder interference system needs to be improved, a double Mach-Zehnder vibration detection system is constructed, the principle of the time delay estimating vibration location is analyzed, and a generalized cross-correlation algorithm for the time delay estimation of the dual path detection signal is proposed, which increases the flexibility and feasibility of the signal frequency domain analysis. The positioning error of the system is reduced by digital filtering. The experimental results show that the system can detect and locate the square signal, impulse signal and knocking signal on the sensing fiber, and the positioning error of less than 20m and repeatable stability detection can be realized on the sensing fiber of 940m. It provides a new solution for the popularization and application of optical fiber vibration sensing technology in mining and industrial fields.