基于最小均方误差算法的光纤振动传感器

Optical Fiber Vibration Sensor Using Least Mean Square Error Algorithm.

作者信息

Wang Yu, Zou Jie, Xu Yuelin, Chen Yu, Liu Xin, Bai Qing, Jin Baoquan

机构信息

College of Physics and Optoelectronics, Key Laboratory of Advanced Transducers and Intelligent Control Systems (Ministry of Education and Shanxi Province), Taiyuan University of Technology, Taiyuan 030024, China.

Science and Technology on Near-Surface Detection Laboratory, Wuxi 214035, China.

出版信息

Sensors (Basel). 2020 Apr 2;20(7):2000. doi: 10.3390/s20072000.

DOI:10.3390/s20072000

PMID:32252485

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7181267/

Abstract

In order to enhance the signal-to-noise ratio (SNR) of a distributed optical fiber vibration sensor based on coherent optical time domain reflectometry (COTDR), a high extinction ratio cascade structure of an acousto-optic modulator and semiconductor optical amplifier is applied. The prior time-frequency analysis and least mean square error algorithm are adopted in the COTDR system for amplitude demodulation and phase demodulation, in order to improve the SNR by noise elimination. The experimental results show that the adaptive filter based on the least mean square error algorithm could realize the extraction of a three-order sinusoidal harmonic signal from strong background noise along the optical fiber and the SNR improvement from 10.4 dB to 42.2 dB. The proposed demodulation algorithm is suitable for the detection of vibration signals with characteristic frequencies in the application of acoustic fault diagnosis for electromechanical devices.

摘要

为了提高基于相干光时域反射仪（COTDR）的分布式光纤振动传感器的信噪比（SNR），采用了声光调制器和半导体光放大器的高消光比级联结构。在COTDR系统中采用先时频分析和最小均方误差算法进行幅度解调与相位解调，以通过噪声消除提高信噪比。实验结果表明，基于最小均方误差算法的自适应滤波器能够从沿光纤的强背景噪声中实现三阶正弦谐波信号的提取，信噪比从10.4 dB提高到42.2 dB。所提出的解调算法适用于机电设备声学故障诊断应用中特征频率振动信号的检测。