ECG Signal Denoising Method Based on Stationary Wavelet Transform with Hyperbolic TangentThreshold Function

In the acquisition process of ECG signals,there are various kinds of noise filled in the ECG signals,which will make the ECG signals become difficult to identify,thus affecting the diagnosis of medical personnel.Denoising the ECG signal is an important part of ECG signal research.This paper adopts the technique based on stationary wavelet transform,aiming at the defects of hard threshold and soft threshold in the denoising process of stationary wavalet transform,a hyperbolic tangent function withvariable parameters(SWTaVHT) is proposed for denoising ECG signals.Moreover,in order to prevent the loss of some high frequency information segments in the process of denoising,the R-peak location information assisted correction method is used to better retain useful signal features.In order to evaluate the effectiveness of SWTaVHT,experiments are conducted on the public database MIT-BIH for a comparative study with existing methods.Experimental results show that the signal-to-noise ratio(SNR),root-mean-square error(RMSE) and percentage root-mean-square difference(PRD) after denoising are better compared to the existing methods.The SWTaVHT denoises the ECG data without changing the amplitude of the original signals,which is better than the existing methods.