Parametric Study of Pin-based Gap Waveguide for Millimeter Wave Slow Wave Structures

Gap waveguides have been proposed for the design of slow wave structures (SWS) of travelling wave tubes (TWT) operating at the millimeter wave. In this paper, we consider a SWS based on a metal pin structure and top metal plate to realize the gap waveguide, loaded with a central corrugation for realizing the synchronism condition with the electron beam. Parametric studies are presented to show the impact of variation of certain critical dimensions of the SWS in order to analyze tolerances and optimization for a W-band TWT (87 - 100 GHz).