JOUR~AL OF APPROXIMATION THEORY 71, 239-251 (1992) Asymptotics for Zeros of Szeg6 Polynomials Associated with Trigonometric Polynomial Signals
نویسندگان
چکیده
The study of Wiener-Levinson digital filters leads to certain classes of polynomials orthogonal on the unit circle (Szego polynomials). Here we present theorems that show that the unknown frequencies in a periodic discrete time signal can be determined from the limiting behavior (as N -+ co) of the zeros of fixed degree Szego polynomials that are orthogonal with respect to a distribution defined from N successive samples of the signal. This proves an essential part of a conjecture due to Jones, Njastad, and Saff concerning the frequency analysis problem. :
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