Investigation of a Megawatt-Class Gyro-TWT Based on Rectangular Dielectric-Loaded Circuit

In this paper, a gyrotron traveling wave tube (gyro-Twt) based on a rectangular dielectric-loaded circuit (RDLC) is investigated and analyzed to generate the megawatt-class output power. The novel RDLC with a large aspect ratio can effectively decrease the current density of electrons due to the operating frequency of TE
01
mode is only determined by the narrow side. A Ka-band RDLC with an aspect ratio of 6.95 is designed, and the pulsed operation results indicate that the device driven by a 60 kV, 50 A electron beam can produce a maximum pulsed peak power of 1.13 MW, corresponding to an efficiency of
$\sim \mathbf{37}.\mathbf{7}\%$
, a saturated gain of 51.5 dB at 34 GHz. The 3 dB bandwidth is 4.5 GHz, and more than 1 MW output power is achieved in 33.5-36 GHz. The design provides a possible approach for developing gyro-TWTs with megawatt-class output power.