A gigawatt Ka-band relativistic backward-wave oscillator with an internal resonant output

The millimeter wave (such as Ka-band) relativistic backward wave oscillator (RBWO) operating at gigawatt power is contemporary pivotal due to the high vulnerability of vacuum breakdown in compact device size. This paper proposes an internal resonant output structure inside a coaxial RBWO, to reduce the maximum field intensity in the slow-wave structure. With optimization on size parameters in simulation, the maximum field intensity of the device is reduced by over half while the total output power is maintained. Simulation results show the proposed device can deliver 1 GW output at 39.85 GHz. This research presents a promising avenue toward achieving high-power millimeter-wave generators.