EHGFs方向可控滤波压制地震勘探随机噪声

Seismic Random Noise Attenuation Based on EHGFs Steerable Filters

为有效提取地震信号同相轴信息,解决以哈密特-高斯函数(HGFs:Hemite-Gauss Functions)为核函数的方向可控滤波器因无方向性而导致同相轴被降频的问题,引入以拉伸哈密特-高斯函数(EHGFs:Elongated Hemite-Gauss Functions)为核的方向可控滤波去噪方法。该方法考虑有效信号与随机噪声在方向性上的差异,通过近似拟合方法构造EHGFs方向可控滤波器,借助EHGFs具有明确的方向性,滤波时沿着轴向进行滤波,提高线性度,减少平滑作用,取得方向滤波数据后再根据数据局部数字特征进行数据重组,达到去噪效果。实验结果表明,该方法具有明显压制随机噪声、恢复有效信号的效果。

Aiming at effectively extracting the event information of seismic signal and solving the issues that the Hemite-Gauss steerable filters have an intrinsic limit which the same amount of smoothing is made in all directions due to the isotropic Gaussian factor, the EHGFs （Elongated Hemite-Gauss Functions） are proposed. This method considers that the desired signal is different from random noise in direction characteristic, generate EHGFs steerable filters by the approximate fitting, which can improve the linearity of the signal and filter along the event to get directional filtered data with less smoothing effect. Then we reconstruct the data on the basis of the digital local features to denoise. Experiment results indicate that this method can significantly suppress random noise and keep the useful signal in seismic processing.