Study and Preliminary Experiment of 105 GHz Extended Interaction Oscillator with Folded Waveguide

In this paper, a folded waveguide was adopted as the slow wave structure (SWS) of the extended interaction oscillator (EIO). An EIO with frequency 105 GHz was studied in detail, including the dispersion relation and the impedance of the SWS, the starting current varying with the period number, the structure of the window and the electron gun (E-gun), and the PIC simulation of the beam-wave interaction with output power 26~50 W and the corresponding frequency 105.26~105.31 GHz. The machining method of the SWS was investigated for fabricating the SWS and the window as well as the E-gun. The preliminary experiment of cold test and hot test was finished, including the performance of the SWS, the window and the E-gun with current density up to 100A/cm2.