次声波法输气管道泄漏检测系统的信号处理

对输气管道泄漏产生的次声波信号进行采集时,受传感器的频域限制,次声波传感器检测到的信号尖端被舍弃,同时自然界中的环境噪声亦对次声波信号产生强烈的干扰。为了降低次声波检测误报率,通过特殊算法对检测信号进行尖端补偿,将真正的泄漏信号与干扰信号快速分离,并选用小波变换的方法对补偿后的信号进行处理,使采集的信号在时域和频域两方面都具有良好的局部特性,且在时频平面的不同位置具有不同的分辨率,对噪声具有更好的抑制作用,同时较精确地提取信号的突变点。通过以上尖端补偿和小波变换信号处理,可以明显地降低误报率和漏报率。

Infrasound wave method-based signal processing of leak detection system of gas pipeline

When the infrasound wave signals from leakage of gas pipelines are collected,signal tips detected by infrasound wave sensors are abandoned due to the frequency domain limit of the sensor,while the ambient noise in the natural world produces a strong interference on the acoustic signal.To reduce false positive rates of infrasound wave detection,it is necessary to make a tip compensation for detection signal through a special algorithm,quickly separate the real leak signals from interference signals,and select the wavelet transform method to process signals after compensation to make collected signals have good local features in time domain and frequency domain and have different resolutions in different position of time-frequency plane,so as to form better inhibitory effect of the noise and more accurately extract signal mutation point.Through the above tip compensation and wavelet transform signal processing,false positive rates and false negative rates can be reduced more thoroughly.