Digital Filter Implementation for Removal of Baseline Wander in ECG Signals

Abstract

The Electrocardiogram (ECG) is a non-invasive and graphic representation of electrical activity of the heart. It is the most general investigation of the heart performed by physicians and is extremely useful for the diagnosis of cardiovascular diseases. The acquired ECG signal may have noises such as baseline wander, power line interference, motion artifacts, muscle contraction, instrumentation noise and electrode-contact noise. Thus the ECG signal needs to be pre-processed to remove these noises. The pre-processing techniques such as Finite Impulse Response (FIR) filter and Infinite Impulse Response (IIR) filter are performed in MATLAB environment. Error measures such as mean absolute error, mean square error, signal to noise ratio, peak signal to noise ratio and statistical measures such as entropy, kurtosis, skewness and energy are computed to find the method suitable for removing the baseline wandering of ECG signal. The suitable filter thus obtained is designed using MATLAB FDATool and the code generated is simulated using Xilinx modelsim 6.5e. It is observed from the results that FIR filter performs better in correcting the baseline wandering. Results demonstrate that FDATool in MATLAB platform thus implemented enables to configure the implementation of the filter by transforming the MATLAB code to Very high speed integrated circuit hardware description language (VHDL) code.