A 35 GHz, high power, wideband, hybrid harmonic-multiplying gyrotron amplifier (Gyrotriotron)

A new triplet gyrotron amplifier, which we call Gyrotriotron, has recently been developed. The device utilizes a 1-2-2 harmonic-multiplying scheme and operates with a short Ku-band gyro-TWT as input stage, a longer Ka-band gyro-TWT as output stage and a multiunit stagger-tuned clustered-cavity (TE mode) as an intermediate stage. A mode converter/filter type of interaction circuit is employed for each stage to minimize spurious mode competitions. In addition to the features of lower magnetic field requirement and lower input frequency, high gain, high efficiency and wide bandwidth are expected for this new gyro-amplifier. A proof-of-principle Gyrotriotron with expected peak power of 500 kW in TE04 mode and 5% bandwidth has been fabricated, and will be soon tested in the Harmonic Gyrotron Lab at the University of Maryland.