Project of a third harmonic W-band gyroamplifier

In this paper we present design of a broadband third-harmonic operating gyro-amplifier with helically corrugated interaction circuit. An analysis of stability of the gyro-TWT with respect to parasitic wave-beam interactions has been performed and the range of parameters at which the gyro-TWT is zero-drive stable is found. According to 3D simulations, the amplifier yields a 6% amplification bandwidth with the maximum output power/gain of 80 kW / 25 dB for a 10-A, 70-kV electron beam.