为了实现海底光缆故障的检测与定位,采用环形M-Z(Mach-Zehnder)干涉结构建立分布式光缆检测系统,利用两路干涉输出的时间差实现定位功能。阐述了该分布式光缆检测系统的组成及工作原理。使用Optisystem软件进行仿真分析,验证系统可行性。利用互相关时延估计法直接在时域上对信号进行处理获得定位结果。理论分析和测试结果表明,该系统能够快速、有效地实现扰动事件的检测与定位,平均定位误差最大为16.5 m。

In order to measure and locate the trouble point of submarine fiber optic cables, a distributed fiber optic cable detecting system based on dual M-Z(Mach-Zehnder) interferometer is discussed. Realize disturbance localization by detecting the time delay of two interference output signals. In this paper, the composition and working principle of the distributed fiber optic cable detecting system is summarized. Optisystem software is used to simulate the system and analyze the feasibility of the system. Cross-correlation algorithm is used to deal with the interference signals in time domain directly to realize position. The experimental result shows that this distributed fiber optic cable detecting system based on the dual M-Z interferometer can achieve disturbance detection and mean position accuracy is 16.5 m. Simulation as well as experimental results are presented to corroborate the theory.