A wideband 140 GHz, 1 kW confocal gyro-traveling wave amplifier

The experimental results of a zero-drive stable, short pulse 140 GHz gyro-traveling wave amplifier are presented. The amplifier has achieved a linear gain of 34 dB, a saturated bandwidth of over 1.5 GHz, and an output power of over 820 W peak at a beam voltage of 38 kV, beam current of 2.7 A, and beam pitch factor of 0.6. The gyro-TWT operates in the HE(0,6) mode of a quasi-optical confocal waveguide.