A high-efficiency V-band radial-line backward wave oscillator with unilateral slow wave structures

In this paper, we propose a high-efficiency V-band radial-line oscillator (BWO), which consists of dual-cavity reflector, unilateral radial slow wave structures (SWSs) and output structure. It operates in TM02 mode to achieve high power capacity. The unilateral SWSs in the novel device have two advantages as follow: One is that fabrication of unilateral SWSs is much easier than that of traditional bilateral SWSs. The other is that the unilateral SWSs have high interaction efficiency with electron beam, which can produce high-efficiency output power. In particle-in-cell simulation results, high power microwaves with a frequency of 63.767 GHz are obtained and the power efficiency is approximately 30% when the diode voltage is 237 kV, beam current is 4.25 kA, and radial magnetic field is 1.7 T