Computation of x-parameters using multipoint moment expansion

Abstract

Recently X-parameters 1 have been proposed as an extension to the concept of S-parameters in order to create a macromodel that captures nonlinear behavior. In this paper, we develop a relation between the X-parameters and circuit moments. Higher order multidimensional moments are then used to efficiently compute the X-parameters as a piecewise polynomial approximation with respect to input power. The proposed approach is shown to be accurate and CPU efficient compared to the brute force methods.