A GENERALIZED EIGENVALUE METHOD FOR FDTD ANALYSES

In this article we apply the generalized eigenvalue method (GEM) to ex tract the complex exponentials from a truncated time record computed b y the finite-difference time-domain (FDTD) code for analyzing microwav e integrated circuits. To obtain accurate scattering parameters withou t further FD TD computations, the truncated FDTD time record is effici ently extended into the future by summing the complex exponentials wit h complex coefficients determined by the least-squares method. Numeric al GEM results with fewer poles are shown to be in good agreement with those obtained by the Prony method with a large number of poles.