Design study of an energy-recirculating G-band self-driving folded waveguide traveling-wave tube

We present a design study on a self-driving folded waveguide traveling-wave tube (FWTWT). This device is an energy-recirculating hybrid vacuum tube which has a G-band FWTWT and a folded waveguide (FWG) structure backward-wave oscillator (BWO) as a self-driving source for the FWTWT. The microfabrication of the proposed circuit has been tried using a computer numerical control (CNC) machine and a super-drill. The detailed circuit simulations based on the analytic equations were compared with the CST Studios™ results, and demonstrated considerably good agreement to each other.