INTERSPEECH 2011

In the present paper, a method is proposed for adaptive estimation and tracking of roots of timevarying, complex, and univariate polynomials, e.g. ztransform polynomials that arise from finite signal sequences. The objective with the method is to alleviate the computational burden induced by factorization. The estimation is done by solving a set of linear equations; the number of equations equals the order of the polynomial. To avoid potential drifting of the estimations, it is proposed to verify with AberthEhrlich's factorization method at given intervals.
A numerical experiment supplements theory by estimating roots of timevarying polynomials of different order. As a function of order, the proposed method has a lower run time than LindseyFox and computing eigenvalues of companion matrices. The estimations are quite accurate, but tend to drift slightly in response to increasing coefficient perturbation lengths.
Bibliographic reference. Pedersen, C. F. / Andersen, Ove / Dalsgaard, Paul (2011): "Adaptive estimation of zeros of timevarying ztransforms", In INTERSPEECH2011, 173176.