Design of Dual-Band High-Power Backward Wave Oscillator using Double Staggered Grating and Pseudospark-Sourced Sheet Beam

We have designed a dual-band backward wave oscillator (BWO) using a double staggered grating (DSG) slow-wave structure (SWS) and a pseudospark-sourced sheet electron beam. In the simulation of the high-frequency characteristics, the DSG SWS has been shown a wide operating band of 72–125 GHz and a high coupling impedance. The complete structure of the BWO consists of 10 DSG SWS units, together with a wideband output structure. In the cold-test simulation of the DSG BWO, the transmission is greater than −7 dB in the band 74–100 GHz, and 109–125 GHz. The hot-test performance of the DSG BWO is analysed by particle-in-cell (PIC) simulation, showing dual-band operation in 75–100 GHz (25-GHz bandwidth) and 108–115 GHz (7-GHz bandwidth), with high output power (max. 162 kW).