AGORA: Adaptive Generation of Orthogonal Rational Approximations for Frequency‐Response Data

ABSTRACT This paper introduces the adaptive generation of orthogonal rational approximations (AGORA) method for rational function approximation of measured or simulated microwave network parameters. The output of AGORA is a state‐space model or a rational function model that is representative of the input data. The generated model can then be used to interpolate the data or to evaluate the data quality. A typical application is the time‐domain signal and power integrity analysis in circuit simulations using the generated model from measured or simulated interconnnects and power distribution networks. AGORA allows estimating the model order for a given error tolerance and does not require any initial estimates or adjustment of hyperparameters.