Design and development of Ku-band 140W space TWT

A Ku-band 140 W space TWT of gain (>55 dB), electronic efficiency (>24%), collector efficiency (>75%), overall efficiency (>55%), I/M components (<-12 dBc) for frequency 10.9-11.7 GHz has been designed and developed for satellite communication system. This paper presents critical design issues and approach related to different assemblies like electron gun, PPM focusing, helix SWS, input & output couplers, and 4-stage depressed collector in order to meet the stringent requirement of space TWTs.