DEVELOPMENT OF A SOFTWARE FOR NOISE AND INTERFERENCE ELIMINATION IN ECG SIGNALS

Abstract

In this dissertation, a software for elimination of noise and interference in ECG signal and for the detection of QRS complex has been developed. A comparison of noise sensitivity for the software developed has been done for QRS detection. Linear phase filtering is proposed for the removal of and power line frequency components in electrocardiograms. In order to remove the large number of computations involved in the digital filtering, that are necessary, the desired filter spectrum is defined periodically. Making use of the property that the spectrum period is 50 Hz, the spectrum has been realized with a considerably reduced number of impulse response coefficients. This, in combination with the necessary impulse response symmetry, leads to a reduction in the number of multiplications per output sample by a factor of 10. A suitable impulse response is designed with a pass-band ripple of less than 0.5 dB and a high stop band attenuation. The applicability of proposed filter is demonstrated by applying the filtering to various leads of exercise ECG.