AN ASSESSMENT OF THE ORTHOGONAL AND BIORTHOGONAL DISCRETE WAVELET TRANSFORM BASED DENOISING OF BIOLOGICAL SIGNALS − A STUDY BASED ON ECG

Wavelets transforms are effective mathematical tools useful in compression and denoising of n-D signals. Subjecting a signal to discrete wavelet transforms (DWT) generates approximation and detailed coefficients that are similar to the coefficients generated by passing the signal through lowpass and high pass filters respectively. Multilevel decomposition (filtering) can be carried out which can successively filter the signal at each bandpass. In this work, a normal sinus rhythm ECG signal noised with a sinewave was denoised by DWT using by members of mother wavelets like coiflet, symlet and biorthogonal families. The denoising performance of the wavelets were evaluated by comparing the signal characteristics of the original and the denoised signals.