摘要
针对目前基于相位敏感光时域反射计(Φ-OTDR)的分布式光纤扰动传感系统信噪比较差的问题,提出采用小波阈值降噪法对系统采样信号进行信号处理的前期降噪。分析系统有效信号特征,采用小波阈值降噪法中强制阈值降噪法、软阈值降噪法以及硬阈值降噪法分别对采样信号进行降噪处理,经过比较选择了阈值降噪法作为降噪算法。定量对比降噪前后扰动信号的信噪比,证明采用小波阈值降噪法中硬阈值法处理后的数据在进行后期定位算法时,信噪比提高近一倍。
In order to solve the existing problem of poor SNR in distributed optical fiber disturbance sensing system based on phrase sensitive optical time domain reflectometer （Φ-OTDR） at the present time, wavelet threshold denoising method is given to reduce the noise in systematic sampling signal before other steps in this paper. Through the analysis of the effective signal＇s characteristics of the system and comparison of the different effects produced by mandatory threshold method, soft threshold method and hard threshold method in wavelet threshold denoising method, hard threshold method is chosen to reduce the noise. In the experiment, the SNR of disturbance signal before noise reduction is compared with that of disturbance signal after noise reduction quantitatively, and it proves that after noise reduction of systematic sampling signal using hard threshold method, the SNR is increased nearly twice in the later process of location algorithm.
出处
《现代电子技术》
2012年第17期51-53,共3页
Modern Electronics Technique
关键词
分布式光纤传感
相位敏感光时域反射计
小波降噪
硬阈值法
distributed optical fiber sensing
phase sensitive optical time domain reflectometer
wavelet denoising
hard threshold method
