REMOVAL OF BASE-LINE WANDER AND POWER-LINE INTERFERENCE FROM THE ECG BY AN EFFICIENT FIR FILTER WITH A REDUCED NUMBER OF TAPS.

Linear phase filtering is proposed for the removal of base-line wander and power-line frequency components in electrocardiograms. In order to reduce the large number of computations required in the digital filtering, the desired filter spectrum was defined periodically. Making use of the property that the spectrum period is 50 Hz, the spectrum can be 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 is demonstrated by applying the filtering to exercise electrocardiograms.