A novel adaptive IIR notch filter for frequency estimation and tracking

In this paper, a variable step size adaptive IIR notch filter is proposed to solve the problems of estimating and tracking the frequency of sinusoidal signal polluted by broad band noise. The bias removal technique is employed in the adaptive procedure to reduce the estimation bias in the implementation of the filter, and mathematical analysis is also used to discuss the estimation bias and MSE. Simulation results prove that the proposed filter is an effective method to estimate and track the frequency.