Design and Performance Analysis of Cascade Digital Filter for ECG Signal Processing

Abstract

The present paper is based on study carried out with an objective of denoising and improving the quality of an ECG signal. In the study four sets of filters were used which are High pass FIR Filter, Adaptive Filter, Notch Filter and Low pass IIR Filter. High pass FIR Filter was designed by different windowing techniques in which Blackman technique was found more effective, Adaptive Filter was designed by LMS and NLMS algorithms in which NLMS algorithm was found to be more suitable and low pass IIR filter was designed by using various approximation methods in which Elliptic approximation method was found more potent. Comparisons of physical parameters like signal to noise ratio and power spectral density has been done by observing the signal before and after applying filter. All these high performance filters were cascaded along with notch filter. Results were compared with the existing papers and our results of experiment showed high SNR improvement after filtering as 7.75dB and low PSD minimization as -35.21 dB/Hz.