Rectangular-to-Circular Waveguide Transitions for High-Power Circular Overmoded Waveguides

Circular overmoded waveguide is being investigated at The Johns Hopkins University Applied Physics Laboratory JHUAPL for low loss, high power microwave transmission near 3.0 GHz. Unfortunately, most microwave rather than overmoded circular waveguide. This problem is usually solved by using metallic waveguide transitions. Design objectives for such transitions include high power carrying capability, low mode conversion, low reflectivity, and low transmission loss. An overview of the theory of waveguide transition operation is presented. It is concluded that a prerequisite for a comprehensive waveguide transition analysis is to solve the uniform waveguide problem for the various cross sections of the transition. A review is included that describes some of the difficulties encountered in developing a computer program package that analyzes uniform waveguides with arbitrary cross sections. A overview is included of important waveguide design issues, several proposed designs, and several different tasks and problem areas one might encounter in a long-term study RRH