二代小波变换在肌电信号消噪中的应用

The Application of Second Generation Wavelet Transform in the De-noising of the SEMG

为了更好地消除混杂在表面肌电信号中的噪声，提出了一种基于二代小波变换的表面肌电信号消噪方法。利用提升算法进行表面肌电信号二代小波分解，得到多层的信号高频细节系数，分别运用软、硬阈值进行处理，对滤波后的信号进行小波重构，恢复消噪后的原始信号。通过对加噪正弦信号和真实表面肌电信号的消噪实验，结果表明：二代小波是一种明显优于一代小波的消噪方法，且硬阈值法优于软阈值法。

To eliminate the noise mixed in the surface electromyography, a de-noising method based on second generation wavelet transform is presented. Firstly, high frequency detail coefficients of multilayer signals are obtained by the second wavelet decomposition through lifting algorithm. Then the signals are filtered using soft threshold and hard threshold separately. Finally, the original signal eliminated noise is resumed by reconstructing fdtered detail coefficient. The de- noising experiments of standard noise adding sine signal and real surface electromyography are carried on. The results show that the second generation wavelet de-noising method is better than the first generation one, the hard threshold method is better than the soft threshold method.