Design of Digital IIR Filter for Noise Reduction in ECG Signal

Abstract

Electrocardiogram (ECG) signal has been widely used in cardiac pathology to detect heart disease. A digital infinite-impulse response (IIR) filter design is proposed in this paper. This includes an implementation and evaluation of butter worth low pass infinite impulse response filter method to remove high frequency noise and for this filter is applied to noisy ECG data sample and original sample are taken as reference signal. The suggested method considers the magnitude response for choosing the cutoff frequency and the FFT spectrum estimate response to find the lowest filter order. The structure and the coefficients of the digital IIR filter are designed using FDA tool in MATLAB. The filter output's average power before and after filtration are calculated using FFT and for simulation of this filter, the hardware is designed using micro controller At mega 16 A. For hardware designing the samples taken are record no. 108 and record no. 119 (taken from MIT-BIH database, ML II signal). Here samples are taken from MIT-BIH arrhythmia database (mitdb) ML II are used.