Self tuned SSRLS filter for online tracking and removal of power Line Interference from Electrocardiogram

Power-Line Interference (PLI) may seriously distort the ECG (Electrocardiogram) signal rendering the ECG analysis inaccurate. Various types of Notch filtering and adaptive cancellation schemes have been used to eliminate PLI interference from ECG. In this paper we propose an enhanced adaptive noise canceller (ANC) based on State Space Recursive Least Square (SSRLS) for elimination of PLI. SSRLS algorithm is a state space model-dependent recursive algorithm characterized by fast rate of convergence and hence exhibits excellent tracking performance. State-space formulation of noise model enables SSRLS filter to be implemented in an instinctive manner in comparison to other approaches. The proposed method is very effective for online tracking of PLI without requiring a reference noise source. The proposed method can also be employed to filter out the PLI even when corrupted ECG signal has low signal-to-noise ratio (SNR).