Performance Comparison of a Second-order adaptive IIR Notch Filter based on Plain Gradient Algorithm

Abstract

This paper presents performance analysis of a second-order adaptive IIR notch filter with constrained poles and zeros in direct form II structure that is adapted by algorithms of indirect and direct frequency estimations based on plain gradient. In this work, the steady-state bias properties and stability bounds of both algorithms are derived in closed form. The simulated processes are performed in order to verify the analytical results. Furthermore, these results of the proposed filter are also compared with those results of the direct form I adaptive IIR notch filter under the same parameters. It has been revealed that the direct form II structure has given the steady-state performance over the direct form I structure.