volume | PIER Journals

Abstract

Field structures of waveguide Y-junction circulators containing irregular shaped ferrite material, such as Y-junction with partial-height cylinder/triangle ferrite posts and metal step impedance transformer, Y-junction with a ferrite sphere, and dual higher order modes circulator, which are classified as different junction resonance modes, are depicted to illustrate the circulating process. The analysis method used is a combination of the mode expansion method and finite element method, which is based on the weak form of Helmholtz equation. Calculated results (return loss, insertion loss and isolation) of these structures are shown and compared respectively to those in literatures. Consistencies have been observed.

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Dr. H. Wu

Dr. Wen-Bin Dou