ANALYSIS AND DESIGN OF A NOVEL NONCONTACTING WAVE-GUIDE BACKSHORT

A new noncontacting waveguide backshort has recently been developed for millimeter- and submillimeter-wave frequencies, The design consists of a metal bar with rectangular holes cut into it, which is covered with a dielectric layer to form a snug fit with the broadwalls of a waveguide. It is mechanically rugged and can be readily fabricated for frequencies from 1-1000 GHz, This paper presents a technique for the theoretical characterization of the backshort, using an approach that combines the mode-matching method and a set of coupled space-domain integral equations. The convergence characteristics of the analysis are included, along with a set of general design guidelines.