最小控制递归平均算法对光纤声音传感系统的降噪作用

Noise Reduction Effect of Minimum Control Recursive Average Algorithm on Optical Fiber Acoustic Sensor System

为了解决恶劣环境下分布式光纤声音传感系统的声音还原问题,搭建了一种基于改进最小控制递归平均(IMCRA)算法的多通道光纤声音传感系统。采用Sagnac和Mach-Zehnder复合光路结构,以单模光纤作为传感单元拾取声音信号,借助光开关实现了多通道信号采集,并通过改进最小控制递归平均算法对声音信号进行降噪、还原及增强处理。实验结果表明:该系统可在长为4km的传感光纤上实现对单音信号和语音信号的多通道扫描拾取,并能够在复杂情况下实现对语音信号信噪比的有效提升,为光纤声音传感系统在恶劣环境下的应用提供了一种新途径。

In order to solve the problem of sound reduction in distributed optical sound sensing system in harsh environment,a multi-channel optical fiber acoustic sensing system based on improved minimum control recursive average(IMCRA) algorithm was established. The composite optical path structure of Sagnac and Mach-Zehnder was built,and the single-mode optical fiber was used as the sensing unit to pick up the sound signal. The multi-channel signal acquisition was realized by the optical switch,and the sound signal was denoised,restored and enhanced by the IMCRA algorithm. The experimental results show that the system can realize multi-channel scanning and picking of single-tone signals and voice signals on the sensing fiber with a length of 4 km,and can effectively improve the signal-to-noise ratio of the voice signal under complicated conditions. A new way for the application of optical fiber acoustic sensing systems is provided in harsh environments.