摘要
在采用肌电信号进行颈肩肌肉疲劳特性分析中,为提高非平稳表面肌电信号(surface electromyography,SEMG)的信噪比,抑制传统强制去噪时在信号奇异点处产生的伪吉布斯(Gibbs)现象,采用平移不变(translation invariance,TI)小波新阈值去噪的方法对肌电信号进行去噪。实验表明,该方法在保留颈肩肌电信号主要特征的前提下,与传统强制去噪方法比较,信号的信噪比(signal-noise ratio,SNR)提高了7倍,均方根误差(root mean square error)降低为原来的四分之一,故该方法更适合在充分保留肌电信号细节特征的前提下,去除颈肩肌电信号中的白噪声和50 Hz工频谐波干扰。
In order to improve the signal-to-noise ratio of non-stationary surface electromyography(SEMG),which is susceptible to noise interference,the Gibbs phenomenon is deduced at the singularity of the signal at the traditional hard threshold denoising.The new threshold denoising method was used to denoise the electromyography(EMG)signal by the translation invariance(T I)wavelet.The experimental results show that the proposed method improves the signal-to-noise ratio of the signal by 7 times compared with the traditional soft threshold denoising method,and reduces the root mean square(R M S)error with the traditional hard threshold denoising method 4 times;So the method is more suitable to fully retain the details of the characteristics of EMG signal under the premise of removing the neck and shoulder EMG in the white noise and 50 Hz frequency interference.
作者
李琰
隋修武
LI Yan;SUI Xiuwu(Tianjin Key Laboratory of Advanced Mechatronics Equipment Technology,School of Mechanical Engineering,Tianjin Polytechnic University,Tianjin 300387,China)
出处
《生物医学工程研究》
2018年第1期52-55,共4页
Journal Of Biomedical Engineering Research
关键词
肌电信号
小波阈值去噪
平移不变性
去噪
信噪比
Surface electromyography
Wavelet threshold denoising
Translation invariance
Denoising
Signal noise ratio
