Design and Cold Test on the Slow Wave Structure of a Wide-Voltage Tuned and High-Power Extended Interaction Oscillator in W-Band

In order to obtain continuously tunable high-power output in
$W$
-band, the slow wave structure (SWS) of a wide tuned and high-power extended interaction oscillator (EIO) was designed and studied in this article. The structure of the designed circuit was described while the operating characteristics were analyzed. The SWS not only has high power output capability but also operates near standing waves with a wide electronic tuning range. The EIO can operate over an electronic tuning range of 1.36 GHz in ensuring the output power no less than 1.6 kW, where the maximum output power over 4.5 kW is obtained at 43.8 kV and 2 A from the simulation. The wide tuning range and the high output power are achieved by increasing the number of periods with offsetting the coupling hole and beam voltage and current in order to match with high impedance modes near to
$2\pi $
. The SWS was processed and cold tested, and its S-parameter distribution was close to the simulation result. The designed 94-GHz extended interaction oscillation can be effectively used to generate wide tuned and high-power microwave radiation sources in
$W$
-band.