Multimode Analysis of Planar Circulators by Boundary Element Method

A combination of the equivalent waveguide model for outgoing planar transmission lines and the boundary element method, using Green's function approach is used. multimode performances(VSWR, Insertion loss, Isolation) for planar circulators can be evaluated from the multimode S-parameters which are calculated with good accuracy from the simple identification in the system of equations given by the boundary element method.