Design of a Microfabricated Planar Slow Wave Structure for a 0.22-THz TWT for Communication, Imaging and Remote Sensing

Abstract

ABSTRACTA microfabricated planar 0.22 THz TWT is being investigated as a high power, broadband amplifier for ultra-broadband wireless communication, imaging and remote sensing. Planar staggered double-vane-loaded rectangular waveguide slow wave structure (SDV-SWS) is selected for the 0.22 THz TWT because of its wide bandwidth, high impedance and low loss, easy fabrication using MEMS technologies with high precision and surface finish, and inherent compatibility for operation with sheet electron beam. A simplified approach is presented for determining initial design parameters of the SDV-SWS of wide bandwidth and high impedance. The initial design parameters of the SDV-SWS are used for analytically determining the dispersion and the impedance characteristics of the structure which are found comparable with the simulated characteristics by the 3D e.m. field simulator CST code. The SDV-SWS is designed for a planar 0.22 THz TWT with a sheet beam of beam voltage 20 kV and beam current 100 mA. In-house developed large signal analysis code (SUNRAY-p) is used to analyse RF performance of the planar TWT over the band. The RF performance of the 0.22 THz TWT as determined using SUNRAY-p code is found comparable with the simulated results by the CST code over the frequency band.