AAA Algorithm for Rational Transfer Function Approximation With Stable Poles

摘要

Signal and power integrity analysis in time-domain requires suitable models for interconnects and power distribution networks, which are often available only in terms of their frequency responses from electromagnetic simulations or measured data. A rational transfer function approximation of such data allows its integration in circuit simulators. Recently the AAA (adaptive Antoulas-Anderson) algorithm has been introduced for rational function approximation. This letter introduces a modification of that algorithm for fitting in terms of the squared variable (s(2)), called AAA(2) algorithm, for generating rational transfer functions with stable poles from frequency response available from simulated or measured data.