f-x域CEEMD与Cadzow滤波相结合去除地震随机噪声

Removal of random seismic noise by combining CEEMD and Cadzow filtering in f-x domain

针对当前f-x域CEEMD分频去噪容易损失倾斜有效信号及Cadzow滤波法秩的大小难以选择等问题,研究了一种f-x域CEEMD结合Cadzow滤波的去噪方法。对原始含噪剖面应用f-x域CEEMD分频处理,利用其在保留水平同相轴方面的优势,将原始剖面分割为水平同相轴剖面和倾斜同相轴剖面。利用Cadzow滤波法通过保留较大的秩和较小的秩分别对水平和倾斜剖面做进一步降噪处理,恢复有效信号,将二者相加得到最终降噪剖面。该方法能恢复在f-x域CEEMD分频去噪中损失的倾斜同相轴,且能优化在应用Cadzow滤波法去噪时对秩大小的选择。数值计算结果证明了该方法的有效性。

In view of the problems that the CEEMD frequency division denoising in thef-x domain is easy to lose the tilted effective signal and the rank of the Cadzow filtering method is difficult to choose, a new denoising method based on the combination of the CEEMD and Cadzow filtering in f-x domain is developed. Firstly, the original noise-containing profile is divided into horizontal event profile and inclined event profile by the CEEMD frequency division processing inf-x domain. Secondly, the Cadzow filtering method is used to further reduce the noise of the horizontal and inclined profiles by retaining a large rank and a smaller rank respectively to restore the effective signal. Finally, the final noise reduction profile is obtained by adding the two together. The inclined event lost in the CEEMD frequency division denoising inf-x domain could be restored and the selection of the rank size in the application of the Cadzow filtering to the denoising could be optimized by this method. The numerical results show that the method is effective .