A novel method for the elimination of power line frequency in ECG signal using hyper shrinkage function

Abstract

This paper proposes a new technique to eliminate the power line frequency from the electrocardiogram (ECG) signal. Donoho and Johnstone (1994) were the first to formalize the wavelet coefficient threshold based shrinkage function for removal of additive noise from deterministic signals. The discrimination between signal and noise is achieved by choosing an orthogonal basis, which efficiently approximates the signal (with few nonzero coefficients). A signal enhancement can thus be obtained by discarding components below a predetermined threshold. In the proposed technique, the shrinkage function is incorporated at the vicinity of power line frequency by selecting the proper subband level. The proposed technique is found to be simple to implement in real-time applications. The computational complexity of the proposed technique is very less compared to any other adaptive techniques. The proposed technique is simulated and tested in MATLAB. The recovered signal is visually pleasant compared with other conventional method.