Modified perturbation theory for wideband finite-element model order reduction in eigen-problems

Modified perturbation theory based on high order Taylor series expansion and congruence transformation is applied to the finite-element model order reduction to accelerate the analysis of waveguide eigen-mode problems. The limit of Taylor series by poles is overcome and the bandwidth of a single-point reduced-order model is greatly improved. Without transforming a Taylor series to a Pade rational function, as in an AWE process, this method is more stable and has a wider bandwidth.