A Study on 94 GHz Low-Voltage, Low-Current Gyrotron

A theoretical and experimental study on a 94 GHz low-voltage, low-current gyrotron is presented in this paper. In order to obtain stable radiation and make great use of the equipment in the lab, the TE_6,2 mode is selected as the operating mode of the desired gyrotron. The efficiency of the electron beam interaction with RF fields under different conditions has been calculated by a code, which is based on the self-consistent nonlinear theory for gyrotrons. The gyrotron is equipped with a single-stage depressed collector and a quasi-optical mode converter. Then, a gyrotron with optimized parameters has been designed, constructed, and tested. An output power of 23 kW is obtained at an accelerating beam voltage of 31.5 kV, a beam current of 1.8 A, and a collector depression voltage of 7.4 kV, corresponding to an overall efficiency of 53%.