基于小波信息熵的分布式振动传感系统的扰动评价方法

A Method for Evaluating the Disturbance in Distributed Vibration Sensor Based on Wavelet Information Entropy

针对基于相敏型光时域反射计(OTDR)的振动传感系统所使用的平均算法、差分算法不能有效实现对扰动的识别定位问题,提出了一种结合小波分析理论和信息熵理论的处理算法,以实现系统对外界扰动的准确评价。在深入分析系统所得信号特征及小波信息熵处理方法特点的基础上,探讨了窗长、步长对评价算法的影响,并使用加权算法对该评价算法进一步优化。实验表明,本方法可以区别噪声信号和扰动信号,实现对外界扰动事件的快速准确识别并精确定位扰动发生的位置,对系统的实际应用有重要意义。

A processing algorithm combined with wavelet analysis and information entropy theory is proposed to settle the problem of average and difference methods′ not being effective enough to evaluate the vibration events in phase-sensitive optical time-domain reflectometer （OTDR） vibration sensing system. Based on a well-developed discussion on the features of acquired signal and wavelet information entropy method, the effect the length of window and step on processing result is revealed. Meanwhile, an adoption of weighting algorithm is proposed for further optimization. Experiments prove that this method performs well in distinguishing noise from disturbance, and can recognize exterior interference in a rapid, accurate way as well as pinpoint the interference location, which can enhance the performance of phase-sensitive OTDR system.