A State-Space Approach and Its Estimation Bias Analysis for Adaptive Notch Digital Filters with Constrained Poles and Zeros

摘要

This paper deals with a state-space approach for adaptivesecond-order IIR notch digital filters with constrained poles and zeros. Asimplified iterative algorithm is derived from the gradient-descent methodto minimize the mean-squared output of an adaptive notch digital filter.Then, stability and parameter-estimation bias are analyzed for the simplifiediterative algorithm. A numerical example is presented to demonstrate thevalidity and effectiveness of the proposed adaptive state-space notch digitalfilter and parameter-estimation bias analysis.