Pole-zero computation in microwave circuits using multipoint Pade approximation - Circuits and Systems I: Fundamental Theory and Applications, IEEE Transactions on

AbstructA new method is proposed for dominant polezero (or pole-residue) analysis of large linear microwave circuits containing both lumped and distributed elements. The method is based on a multipoint Pad6 approximation. It finds a reducedorder rational s-domain transfer function using a data set obtained by solving the circuit at only a few frequency points. We propose two techniques in order to obtain the coefficients of the transfer function from the data set. The proposed method provides a more efficient computation of both transient and frequency domain responses than conventional simulators and more accurate results than the techniques based on single-point PadC approximation such as asymptotic waveform evaluation.