An algorithm for simultaneous magnitude and phase approximation of bivariate rational polynomials

摘要

An algorithm is presented for simultaneous magnitude and phase approximation of bivariate rational polynomials. The algorithm is reminiscent of the original differential correction (ODC) algorithm (Barrodale (1972)) for real rational minimax approximation, however the basic iteration of the presented algorithm is not linear but quadratic in the optimization parameters. The stability and the convergence of the algorithm are proven and its application is exemplified.