膈肌肌电信号中心电干扰去除技术的一种方法

本文基于小波信号分解与重建理论和自适应滤波技术相结合的方法,以去除膈肌肌电信号中的心电干扰. 首先,采用小波分解把肌电信号中包含心电干扰的低频段分离出来,这部分信号经过自适应滤波处理后压低膈肌肌电信号,突出心电信号,然后从肌电信号中减去通过自适应滤波得到的心电噪声,再与处理后的细节进行小波的信号重建,得到心电干扰较少的EMGdi信号. 通过对真实的临床医学数据处理,并与常用的高通滤波方法作比较,结果表明,本文所提方法的输出信号的信噪比明显提高,对比处理前后信号的功率谱发现处理后的信号的频谱明显向高频移动,表明该方法取得了较好的去噪效果.

A Method to Remove ECG Disturb in EMGdi Signal

In order to remove electrocardiograph(ECG)interference in electromyography of diaphragm(EMGdi)signal,a cancellation technique with a combination of wavelet decomposition and reconstruction and adaptive filtering is presented in this paper. Firstly,the low frequency components of EMGdi signal containing ECG are separated out by wavelet decomposition. Secondly,the low frequency components obtained are filtered by the adaptive filter in order to lower the EMGdi and highlight the ECG. Then the ECG noise obtained by filtering is removed from the EMGdi signal. Finally,the EMGdi signal with less ECG interference is obtained by wavelet reconstruction. By comparing the results of real clinical signal with those of simple high-pass filtering,it shows that Signal-to-Noise Ratio and power spectrum had distinctly improved.