Surface impedance implementation of high frequency conductor losses using susceptance element equivalent circuit model and model order reduction

A surface impedance implementation of the skin effect for a finite difference frequency domain solver is discussed. Boundary conditions are modeled as current source elements at the surfaces of conductors of the susceptance element equivalent circuit model for the microwave structure. A Taylor series approximation is used to expand the frequency term in the skin effect model, such that multi-point model order reduction techniques can be used to reduce the problem size. This implementation has been tested against measurement data and other solvers for a bandpass filter.