FREQUENCY MULTIPLIED HARMONIC GYROTRON-TRAVELING-WAVE-TUBE AMPLIFIER

Numerical simulations of a W-band two-stage tapered, frequency multipl ied gyrotron-traveling-wave-tube amplifier are reported. Unlike conven tional harmonic gyrodevices, a drive signal at the fundamental harmoni c frequency is injected in the first stage for beam modulation, and am plified output radiation is extracted from the third harmonic cyclotro n resonance interaction. Numerical results show that broadband millime ter wave radiation is obtained with an efficiency of 10%-15%, a gain o f approximately 30 dB, and an instantaneous bandwidth of approximately 10% at a center frequency of 95 GHz for DELTAupsilon(z)/upsilon(z) = 2%.