Implementation of optimized low pass filter for ECG filtering using verilog

Abstract

Electrocardiogram is a standard method used for the diagnosis of heart related disease. QRS complex plays an important role in Electrocardiogram signal processing since it is the prominent feature of Electrocardiogram signal. One of the important modules in the QRS detection algorithm is filtering. Electrocardiogram signal is processed to filter out unwanted signal through digital filtering. The main objective of this paper is to compare the resource utilization of hardware realization consumed between Direct Form I structure and Direct Form II structure. In this work, Infinite Impulse Response low pass filter to remove high frequency noise is designed with a passband frequency and stopband frequency of 5 and 25 Hz respectively. The designed filter is verified using Matlab Filter Design Analysis tool and realized in hardware using Verilog. Both the results show that the unwanted signals in the raw ECG signal are attenuated through the designed filter. The resource utilization result shows improvement with optimized Direct Form II implementation. The amount of look up tables, flip flop and digital signal processing used with Direct Form II structure shows a reduction to 0.26%, 0.12% and 2.50% respectively compared to 1.17%, 0.20%, 2.92% of utilization with Direct Form I structure.