An efficient method for estimation of power line interference in ECG

In this paper we present a computationally efficient method for frequency estimation of power line interference (PLI) present in an ECG signal. Accurate estimation of PLI frequency leads to its effective removal from ECG signal. Using an intelligent frequency search approach, we achieve a high resolution estimate of PLI frequency with minimal discrete Fourier transform evaluations. Computational complexity of proposed algorithm is much reduced as compared to Fast Fourier Transform (FFT). The proposed approach is equally effective in non-stationary environment, where PLI frequency drifts with time.