Accurate Broadband S Parametrization from Narrowband Data Using the Cauchy Method

Abstract

of the polynomials and their coefficients. With the polynomial coefficients at hand, one can evaluate the parameter at an arThe Method Of Cauchy has been med t' bitrary number of frequency points. extrapolate a desired parameter over a broad range of frequencies using some information about the parameter over a narrower band. The approach is to assume quency, is a ratio of two polynomials. The Problem is to determine the order of the Let us represent the parameter as a ratio PolYnomi& and the coefficients therein. of two polynomials. Hence the parameter This technique also uses the method of (HI, as a function of frequency (s), is 4s) Total Least Squares to solve the resulting matrix equations.