小波尺度谱阈值算法在膈肌肌电降噪的应用  

Application of Wavelet Scalogram Threshold Algorithm in Electromyography of Diaphragm Denoising

作　　者：杨智[1] 罗国[1] 范正平[1] 

机构地区：[1]中山大学信息科学与技术学院,广州510006

出　　处：《信号处理》2013年第5期647-655,共9页Journal of Signal Processing

基　　金：国家自然科学基金资助项目(60704045)

摘　　要：为了去除膈肌肌电信号中的心电干扰,提出了一种小波尺度谱阈值的处理方法。首先,对信号进行五尺度的小波分解,并且把小波系数转化为小波尺度谱;其次,针对心电信号在尺度谱上高于周围两边信号的特点,提出尺度谱阈值对心电信号进行滤除;最后,小波尺度谱映射回小波系数,重构小波系数得到降噪后的膈肌肌电信号。对临床采集的膈肌肌电信号进行实验分析,并与小波阈值方法进行对比,结果表明本文方法降低了心电干扰并且保留膈肌肌电信号的特征。A denoising method based on wavelet scalogram threshold was proposed in this paper to remove electrocardio- graphy （ECG） interference. Firstly, electromyography of diaphragm （EMGdi） signal were decomposited by wavelet at the fifth scale, on the other hand, wavelet coefficients were conveyed to wavelet scalogram. Secondly, ECG interference were removed by wavelet scalogram threshold because ECG interference were higher than those signal beside them. Finally, EMGdi signal were gotten by compositing wavelet coefficients after reflecting wavelet scalogram to wavelet coefficients. Comparing the results with the wavelet threshold method, it shows that the proposed method can eliminate the ECG interfer- ence in EMGdi and reserve its signal characteristics effectively.

关 键 词：小波尺度谱 阈值 心电干扰 膈肌肌电信号 

分 类 号：R318.04[医药卫生—生物医学工程]