On the theory of frequency-quadrupling gyroklystrons

In this paper, frequency-quadrupling three-cavity gyroklystrons with successive frequency-doubling in each stage are considered. First, it is shown that such device operating in the W band at the TE4,2-mode can deliver up to 30kW output power in the regime of stable amplification with the density of Ohmic losses acceptable for continuous-wave (cw) operation. The corresponding efficiency is in the range of 17%–20%. Then, the device is scaled to 0.5THz frequency and optimized for operation at the TE4,5-mode. At this frequency, the frequency-quadrupling gyroklystron driven by the 60kV electron beam with the beam current less than 1 A can deliver up to 1kW power with acceptable Ohmic losses. The corresponding efficiency is in the range of 1%–2%.