基于维纳滤波的50Hz工业干扰去噪方法研究及应用

Research and application of 50Hz interference elimination method based on Wiener filtering

50Hz工业干扰是地震资料中一种常见的噪声，由于它与有效信号的频率范围重叠，影响了地震资料的品质。常规的消除50Hz噪声方法是陷波处理，它在切除噪声的同时，也切除了有效信号。本文研究了一种基于最小平方滤波原理的消除50Hz干扰波算法。它通过设计一个参考正弦道，并通过维纳滤波器来调整该参考道的振幅和相位．从而使其与数据道中的50Hz噪声达到最佳匹配。在时域，用数据道减去参考道，即可达到单频去噪的目的。由于该方法不是在频率域实现，既可准确实现单频去噪，又可避免吉布斯现象的发生，因此有较高的保真度。

50 Hz power interference is a common phenomenonl in seismic data, which is superimposed with the main frequency zone of the effective signal and has an influence on the quality of the data. Conventional processing method for eliminating 50 Hz interference is notch-filtering technique, and it may notch the signal when canceling the noise. In this paper, a digital least-squares filtering algorithm was studied for canceling stationary sinusoidal noise. An analytic sinusoidal trace was generated at the frequency of the interfering noise. A short Wiener least-squares filter is then used to match the amplitude and the phase of the sinusoid with the stationary sinusoidal noise on the data trace. In the time domain, the reference sinusoidal trace is subtracted from the data trace removing the sinusoidal noise with single frequency. This method is not carried out in the frequency domain, which not only removes the noise with single frequency, but also avoids Gibbs＇ s phenomenon, so it has higher fidelity.