A method for improving power capability of relativistic backward wave oscillator

This paper analyzes and simulates the RF breakdown in relativistic backward wave oscillator(RBWO). The RF breakdown which occurs on the surface of resonant reflector and slow wave structure(SWS) is induced by field emission. A method is proposed for reducing the surface field intensity, which utilizes cascade feedback reflector and trapezoid SWS with chamfering. The trapezoid SWS is axially lengthened at the minimum radius place for weakening field intensity so that the power capability of RBWO is increased availably. Simulation results indicate that the field intensity reduces from 1 400 to 570 kV/cm on the cascade feedback reflector, and from 1 100 to 780 kV/cm on the trapezoid SWS. Experiment results indicate that the microwave power and the pulse duration increase. A microwave with a p