Harmonic adaptive noise canceler for electrocardiography with no power-line reference

Electrocardiograms (ECGs) are of great importance as they provide plenty of information for the cardiologists. Power-line interference is a major source of distortion for ECGs. Notch filters have been proposed to reduce this kind of interference but they cannot track frequency variations and cannot reduce the power-line harmonic distortion. Adaptive canceling techniques have been proposed to track the frequency variations and reduce the harmonic distortion, yet they are dependent on sampling an external power-line reference, increasing the system complexity. In this paper we propose a modified adaptive canceler that can reduce the harmonic power-line interference without the need to sample an external power-line reference. We show that the performance of our canceler is comparable to the idealistic adaptive canceler that is dependent on sampling an external power-line signal.