EMD端点效应抑制的一种实用方法

根据工程上常见的非平稳随机信号可预测性差、波形不规则等特点,在研究和总结现有端点延拓方法的基础上,提出了一种实用的端点效应抑制方法——极值平移法。该方法以信号端点及其附近极值的特征作为延拓依据,分别在信号两端各添加2个极大值点和2个极小值点,以此达到抑制端点发散的目的。仿真信号和实测响应的分解结果表明,该方法计算效率高,可有效减轻端点效应对经验模态分解(EMD)结果的影响。

Practical Method to Restrain the End Effect of EMD

In view of the facts that the random signals obtained in engineering usually have poor predictability and irregular wave shape,and based on studying the existing technique to extend end points,a practical method to restrain the end effect,i.e.extrema shift method,is proposed.According to the features of end points and the extrema near the end,four shifted extrema are added to each end of the signal respectively,with the purpose of restrain the end points from divergence.Decomposition results of simulation signal and measured response indicate that the proposed method possesses high calculation efficiency,and can relief the influence of end effect remarkably.