Design of an Input Coupler for an X-Band Traveling Wave Tube Amplifier

The University of New Mexico is working on developing a multi-stream Traveling Wave Tube (TWT) amplifier. One of the first steps to be taken during the design of a TWT amplifier is to design an input coupler to couple power from a High Power Microwave (HPM) source to the slow wave structure of the amplifier. In order to aid in the development of a TWT which operates in X-Band, multiple options for input couplers have been designed for use in a greater TWT project at the University of New Mexico. The primary tasks to be addressed with these input coupler designs are: converting HPM in the TE10 propagating mode in a rectangular waveguide to that of a TM01mode in circular waveguide, and ensuring that this coupling can occur for a sufficient bandwidth for the application. This oral presentation will describe progress-to-date on this effort.