A Ku-band radial transit time oscillator with high-power capacity

In order to improve the power capacity of a high-power microwave (HPM) generator, a Ku-band radial transit time oscillator (RTTO) with a trapezoidal resonator is designed. Compared with the traditional RTTO, both the modulation cavity and the extraction cavity are trapezoidal, which can modulate the electron beam more effectively. At the same time, the conductor tips on both sides of the cavity are farther, which helps to avoid the enhancement of the local electric field at the conductor tip, so as to reduce the risk of radio frequency (RF) breakdown. In particle-in-cell (PIC) simulation, the proposed Ku-band RTTO can output HPMs with the power of 1.66 GW and the frequency of 14.33 GHz, and the working efficiency is 41%. The maximum radial electric field intensity in the extraction cavity is 0.76 MV cm(-1), lower than the RF breakdown threshold of metallic materials, which can effectively improve the power capacity of the device.