基于变分模态分解的相关能量熵自适应阈值去噪  

Adaptive Threshold Denoising of Relevant Energy Entropy Based on Variational Modal Decomposition

作　　者：刘霞[1] 李文[2] LIU Xia;LI Wen(Institute of Electrical Information,Northeast Petroleum University,Daqing 163318,Heilongjiang;Northeast Petroleum University,Institute of Architectural Engineering,Heilongjiang,163318)

机构地区：[1]东北石油大学电气信息工程学院,黑龙江大庆163318 [2]东北石油大学土木建筑工程学院,黑龙江大庆163318

出　　处：《吉林大学学报（信息科学版）》2019年第5期518-525,共8页Journal of Jilin University（Information Science Edition）

基　　金：黑龙江省自然科学基金资助项目(F201404)

摘　　要：为有效抑制噪声对地震数据的影响,根据地震信号的时频特性,提出了基于变分模态分解的相关能量熵阈值去噪方法。采用变分模态分解算法将地震信号分解为频率由高频到低频且具有一定带宽的模态分量,计算各模态分量与地震信号的规范化相关系数,实现对各模态分量中的有效信息和噪声的定位。将去除有效信息的各模态分量分成若干子区间,分别计算各子区间的噪声能量熵,选取能量熵最大区间的模态分量系数作为该分量的噪声方差获得该分量的阈值,再将经阈值处理后的各模态分量重构得到去噪信号。通过对合成地震模型和实际地震信号进行去噪处理,并与直接去除高频分量的变分模态分解去噪方法进行了对比,结果表明,该方法能在强噪声环境下更有效地提取地震信号中的有效成分,提高信噪比。Seismic signal is a kind of non-stationary signal, which is composed of seismic subwaves with different amplitude and frequency at different propagation times. According to the time-frequency characteristics of seismic signals, a denoising method based on the relevant energy entropy threshold of variational modal decomposition is proposed. The variational modal decomposition algorithm is used to decompose seismic signals into modal components from high frequency to low frequency and a certain bandwidth. The normalized correlation coefficient between the modal components and the seismic signal is calculated. And the effective information and noise in the modal components are located. Each modal component is divided into several sub-ranges, and the noise energy entropy of each sub-interval is calculated separately. The modal component coefficient of the maximum range of energy entropy is selected as the noise variance of the component to obtain the threshold of the component. The synthetic seismic model and the actual seismic signal are de-noised and compared with the variational modal decomposition and de-noising method that directly removes high-frequency components. The results show that this method can effectively extract the active components of seismic signals and improve the signal-to-noise ratio.

关 键 词：变分模态分解 地震信号 能量熵 自适应阈值 去噪 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术] P631.4[自动化与计算机技术—计算机科学与技术]