Digitization of electrocardiogram (ECG) signals using delta-sigma modulation

This paper discusses an over-sampling technique, namely delta-sigma modulation, with special attention paid to its application in digitizing electrophysiological signals such as ECG. Using simple circuitry consisting of operational amplifiers and flip-flop, the delta-sigma modulation system can be implemented. The original signal can be reconstructed by simply applying the digital bit stream through a low-pass filter. The output signal resembles the original signal as shown experimentally. Therefore, the results show the feasibility of this method of digitizing ECG signals with simple circuitry in both digitizing and reconstructing ends.