管道泄漏检测中的噪声自适应抑制

Adaptive noise suppression in pipeline leak detection

在供水管道泄漏检测中,干扰和环境噪声直接影响到泄漏检测的有效性和漏点定位的精度,因此有必要对检测信号进行噪声抑制,增强检测信号的信噪比,以保证可靠检测和准确定位。提出一种根据不同带宽信号与噪声自相关长度的差异,利用线性增强器和预测器分别自适应抑制检测信号中的窄带噪声和宽带噪声的方法。该方法不需要任何先验知识就可以自适应抑制与有用信号带宽不同的噪声,处理后数据的信噪比较处理前平均提高4 dB以上,对实际的泄漏检测信号处理后,使得定位误差平均减小0.3 m以上,并且降低了误检率。

In pipeline leak detection, interference and environment noise directly influence the effectiveness of leak detection and the accuracy of leakage location. the SNR of leak detection signals for ensuring It is essential to suppress noises in leak detection s reliable detection and accurate location. According ignals and improve to the fact that the autocorrelation lengths vary with the bandwidths of signals and noises, this paper proposes a new adaptive noise suppression method, which uses adaptive linear enhancer and predictor to suppress narrow band and wide band noises, respectively. In this method, no priori-knowledge is necessary for adaptively suppressing the noise that has different bandwidth with useful signals. After the proposed processing, the signal-to-noise ratios of the data are improved by more than 4 dB. After processing the actual leak detection signals, the leak location errors are reduced by more than 0.3 m in average; and the fault detection rate is also reduced.