Bias Removal in Equation Error Adaptive IIR Notch Filter with Constrained Poles and Zeros

A new equation-error based gradient algorithm, which is derived from standard PG (plain gradient) algorithm, is proposed for a second-order adaptive IIR notch filter with constrained poles and zeros. The proposed technique employs the technique of minimizing an unconstrained error function to remove the bias in an estimated coefficient. It is demonstrated that the suggested method gives unbiased IIR system parameter estimation