双M-Z型光纤振动传感器分级互相关定位方法

Hierarchical cross-correlation location method for dual M-Z optical fiber vibration sensors

为提高双马赫-曾德尔(M-Z)干涉型分布式光纤传感器对振动事件的定位速度,提出了一种分级互相关定位方法。首先,对双向干涉信号降采样,通过互相关运算进行初步定位;然后,原始干涉信号在初步定位结果附近进行局部互相关以获得振动事件的精确位置。实验结果表明:和传统互相关方法相比,该方法在保证定位精度的前提下,能够缩短双M-Z干涉型光纤振动传感器的定位时间,提高定位效率。

In order to improve the speed of locating vibration events with dual Mach-Zehnder(M-Z)interferometer-based distributed optical fiber sensors,a hierarchical cross-correlation location method is proposed.Firstly,the bidirectional interference signals are down-sampled,and the initial event location is obtained by cross-correlation operation.Then,the local cross-correlation of the original interference signals is carried out according to the initial location result and the final location of the vibration event is determined.The experimental results show that,compared with the traditional cross-correlation method,this method can shorten the positioning time and improve the positioning efficiency of the dual M-Z interferometric fiber vibration sensor on the premise of ensuring the positioning accuracy.