Designing and Implementation of Algorithms on MATLAB for Adaptive Noise Cancellation from ECG Signal

Abstract

The medical monitoring devices are more sensitive for the biomedical signal recording and need more accurate results for every diagnosis. The low frequency signal is destroyed by power line interference of 50 Hz noise, this noise is also source of interference for biomedical signal recording. The frequency of power line interference 50 Hz is nearly equal to the frequency of ECG, so this 50 Hz noise can destroyed the output of ECG signal. One way to remove the noise is to filter the signal with a notch filter at 50 Hz. However, due to slight variations in the power supply to the hospital, the exact frequency of the power supply might (hypothetically) wander between 47 Hz and 53 Hz. A static filter would need to remove all the frequencies between 47 and 53 Hz, which could excessively degrade the quality of the ECG since the heart beat would also likely have frequency components in the rejected range. To circumvent this potential loss of information, an adaptive filter has been used. The adaptive filter would take input both from the patient and from the power supply directly and would thus be able to track the actual frequency of the noise as it fluctuates [2].