基于MEEMD和二代小波阈值的表面肌电信号去噪处理  

Surface electromyogram signal denoising based on MEEMD and second-generation wavelet threshold

作　　者：武壮 王勇[1] 肖飞云 WU Zhuang;WANG Yong;XIAO Feiyun(School of Mechanical Engineering, Hefei University of Technology, Hefei 230009, China)

机构地区：[1]合肥工业大学机械工程学院,安徽合肥230009

出　　处：《合肥工业大学学报（自然科学版）》2021年第7期869-874,908,共7页Journal of Hefei University of Technology：Natural Science

基　　金：国家自然科学基金联合基金资助项目(U1713210)。

摘　　要：表面肌电(surface electromyogram,sEMG)信号能够反映神经肌肉的相关活动信息,被广泛应用于假肢控制、临床医学等领域,而获取干净的sEMG信号是精确地解释和应用信号的先决条件。为了消除混杂在sEMG信号中的噪声,文章提出了一种基于改进的经验模态分解(modified ensemble empirical mode decomposition,MEEMD)与二代小波改进阈值函数相结合的sEMG信号去噪方法。对含噪的sEMG信号进行MEEMD分解,再对高频的本证模态分量(intrinsic mode function,IMF)进行二代小波改进阈值函数去噪,将处理后的高频IMF分量和低频IMF分量以及残余信号进行重构,重构后的信号即为去噪sEMG信号。仿真结果表明,基于MEEMD与二代小波改进阈值函数方法的去噪性能指标高于其他方法;实验结果表明,该方法结合了MEEMD和二代小波的优点,能够很好地消除噪声,且能最大限度地保留信号中的有用信息。Surface electromyogram(sEMG)signal can reflect neuromuscular activity information and is widely used in prosthetic control,clinical medicine and other fields.The acquisition of a clean sEMG signal is a prerequisite for an appropriate interpretation and application of the signal.In order to eliminate noise mixed in the sEMG signal,a sEMG signal denoising method based on modified ensemble empirical mode decomposition(MEEMD)and second-generation wavelet improved threshold function is proposed.Firstly,MEEMD decomposition is performed on the noisy sEMG signal,and then the high-frequency intrinsic mode function(IMF)is denoised by the second-generation wavelet improved threshold function.Finally,the processed high-frequency IMF component and low-frequency IMF component are reconstructed.The reconstructed signal is the denoised sEMG signal.The simulation analysis shows that the denoising performance indicators based on MEEMD and second-generation wavelet improved threshold function method are higher than those of other methods.The experimental results show that the method combines the advantages of MEEMD and second-generation wavelets,can eliminate noise well,and can retain the useful information in the signal to the utmost.

关 键 词：表面肌电(sEMG)信号 去噪 改进的经验模态分解(MEEMD) 二代小波 

分 类 号：TP212.3[自动化与计算机技术—检测技术与自动化装置]