Author: Dean Korosec
Mentor: Asst. Prof. Dr.  Damjan Zazula
Co mentor: Asst. Prof. Dr. Matjaz Colnaric
Date: Apr. 1993

Off-Line Analysis of One-Dimensional Bioelectrical Signals

Keywords: digital signal processing, cardiology, cardiograph, cardiac infraction, ECG signal, exercise test, complex QRS, personal computer, fast Fourier transform, digital filtering

UDK: 681.32.01

Abstract: We describe some basic facts about electrocardiographic signals, their physiological background, meaning and importance. The way of recording and storing this kind of signals with personal computer is presented. The discrete Fourier transform is introduced as a basic tool for spectral analysis of the finite discrete sequences and the fast Fourier transform as a way for its calculation on digital computers is thoroughly discussed. Some digital filtering techniques with observation of filter spectral characteristics are explained, especially for low pass and band pass digital filters with integer values. Also one of the computer-aided methods for constructing digital filters is described.

Computer program for off-line analysis of electrocardiograhic signals, where these procedures are implemented, is described in the final chapter. Some of the program features are: viewing and browsing of the loaded signal, measuring time intervals and signal amplitudes, zooming in or out, selecting part of the signal, performing filter operation, spectral analysis, calculating the average heart beat, etc. Average heart beat is used for calculating come parameters useful while diagnosing possible heart attack.