Periodogram is a graph showing the power spectrum density (PSD) of a signal, having power by frequency (dB/Hz) in y-axis and frequency (Hz) in x-axis. In other words it shows the corresponding power of the frequency components of the signal. Abnormalities in electrocardiograms (ECGs) show different frequency components in their power spectrum density. In this paper power spectrum density of the QRS complexes has been obtained from normal as well as diseased ECGs to compare the differences between their frequency components. QRS complexes are chosen because it shows distinct differences for different heart diseases. This process can be an effective way to identify abnormalities in ECGs.

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periodogram power spectrum density electrocardiograms QRS complexes