Denoising ECG by a New Wavelet Threshold Function

Electrocardiogram (ECG) signal is an important physiological signal which contains cardiac information and is the basis to diagnosis cardiac related diseases. The advantages of wavelet analysis are illustrated by results from denoising the ECG signals for its highly versatility. In this paper, an improved threshold function, erf function, is proposed to overcome the deficiency of the classic soft and hard thresholds. The performance is evaluated on not only four benchmark signals but also actual ECG signals. The proposed threshold function for wavelet yields the best SNR improvement among commonly used wavelet threshold functions on the MIT-BIH arrhythmia database.