基于SWT和双变量阈值函数的ECG信号去噪

摘要

针对心电信号易受到肌电噪声、工频噪声、基线漂移、电极接触噪声以及环境噪声等的干扰, 提出一种基于平稳小波变换和双变量阈值函数的ECG信号去噪方法.通过对ECG信号进行多层平稳小波变换, 依据噪声在不同分解层的特点, 对变换后的细节系数采用不同的阈值去噪方案.这种方法可避免信号重构后的丢失, 能较好地保留原始信号的完整性, 在提高信号信噪比的同时降低均方误差.通过对MIT-BIH数据库的实测数据进行仿真实验分析, 验证了所提算法的有效性.%An ECG signal denoising method based on stationary wavelet transform and bivariate threshold function was proposed, since the ECG signal is easily subjected to electromyography noise, power frequency noise, baseline drift, electrode contact noise and ambient noise.Multi-layer stationary wavelet transform was used for ECG signals, and different threshold de-noising schemes were used for the transformed detail coefficients obtained according to the characteristics of the noise in different decomposition layers.The method can avoid the loss of signal reconstruction, preserve the integrity of the original signal better, and improve the signal to noise ratio of the signal while reducing the mean square error.Through simulation experiments on the measured data of MIT-BIH database, the validity of the proposed method is verified.