A high efficiency Q-band folded waveguide Traveling-Wave Tube

A Q-band Traveling-Wave Tube was fabricated with folded waveguide (FWG) as its slow wave structure (SWS). The device can deliver 200 Watts power from 43.5 to 45.5 GHz. The electron efficiency is more than 8 % and the total efficiency is more than 25% with one stage depression collector. The test result shows it will be a promising high power millimeter wave source.