Analysis of Junction Circulators for Microwave Integrated Circuits

Junction circulators with ferrite and dielectric layers parallel to the junction plane are analyzed using a two-dimensional mode matching technique. The theory holds for arbitrary transverse field distributions of the coupling transmission lines. Thus microstrip circulators and fin-line or slot line circulators can be treated without major modifications. Results are shown for a microstrip circulator with a ferrite disk below the substrate.