基于Hermite插值的小波模极大值重构滤波的肌电信号消噪方法

Hermite Interpolation-Based Wavelet Transform Modulus Maxima Reconstruction Algorithm's Application to EMG De-noising

为了消除混杂在肌电信号中的噪声,该文提出了基于Hermite插值的小波模极大值重构滤波的肌电信号消噪方法。该方法先对肌电信号进行小波分解;其次,根据小波系数的奇异性,利用信号与噪声模极大值在小波尺度上的不同变化特性,分离出信号与噪声;再次,用Hermite插值法重构小波系数;最后从重构的小波系数恢复成去噪后的信号。实验结果表明,Hermite插值的小波模极大值重构能有效地去除噪声,提高信噪比,且保留了肌电信号的细节信息,为肌电信号的特征提取和模式识别创造了良好的条件。

In order to eliminate the noise mixed in EMG signal, a Hermite interpolation- based wavelet transform modulus maxima reconstruction algorithm is proposed. The obtained EMG signal is decomposed using the wavelet transform; the singularity and different properties of the signal and noise of the wavelet coefficient modulus under the different scales of wavelet transformation are used to separate the signal and noise; then the wavelet coefficients are reconstructed using Hermite interpolation; Finally, the de-noised signal is got by the wavelet reconstructed algorithm. Experiments show that, the method has good performance in removing noise, improving the signal-to-noise ratio and reserving the detailed information, which brings in favorable conditions to feature extraction and pattern recognition of EMG.