Helically corrugated waveguide with dielectric lined drift section for a 263 GHz gyro-TWT

Gyro-TWTs with helically corrugated interaction region (HCIR) have shown to be effective for broadband and high-power amplification of signals up to the W-band. In this publication, versions for 263 GHz (G-band) are proposed, which are able to generate above 1 kW of output power with a gain of 30 dB and 50 dB respectively. To avoid self-oscillations, a dielectric lined drift section is introduced and its effect on the interaction investigated. Furthermore, the effect of a non-ideal electron beam on the amplifier gain is examined. It is found that it has a great influence on the bandwidth; its influence on the maximum gain, however, is limited.