Model Order Reduction for Systems with Non-Rational Transfer Function Arising in Computational Electromagnetics

We consider model order reduction of a system described by a non-rational transfer function. The systems under consideration result from the discretization of electromagnetic systems with surface losses [1]. In this problem, the frequency parameters appears nonlinearly. We interpret the nonlinear functions containing s as parameters of the systems and apply parametric model order reduction (PMOR) to the system. Since the parameters are functions of the frequency s, they are coupled to each other. Nevertheless, PMOR treats them as individual parameters. We review existing PMOR methods, and discuss their applicability to the problem considered here. Based on our findings, we propose an optimized method for the parametric system considered in this paper. We report on numerical experiments performed with the optimized method applied to real-life data.