Adaptive Normal State-Space Notch Digital Filters Using Gradient-Descent Method.

The major purpose of this paper is to explore an adaptive recursive notch digital filter by employing the normal state-space description of a second-order notch filter with single frequency and applying the gradient-descent method. Another is to analyze the stability and frequency-estimation bias for the gradient-descent iterative algorithm. Finally, a numerical example is presented to demonstrate the validity and effectiveness of the adaptive recursive notch filter and frequency-estimation bias analyses. [ABSTRACT FROM AUTHOR]