Analysis and design of radial waveguide E-plane hybrids

This paper presents a computer-aided design of two different types of radial waveguide E-plane 3 dB hybrids utilizing a newly derived magnetic impedance matrix. One is a novel configuration composed of four E-plane waveguides radially coupled to a circular cavity. The other is a modified rat-race circuit consisting of a coaxial cavity and four E-plane waveguides with an impedance transformer. As a result of optimizing the circuit structure and dimensions, a desirable hybrid performance is realized for both types. In addition, computed results by an electromagnetic field simulator are shown to verify this analytical and design method.