Second-harmonic Ka-band gyro-TWT with axis-encircling electrons

A 30 GHz second-harmonic TE/sub 21/ gyro-TWT amplifier is being constructed at UCD that will be driven by a 70 kV, 3.5 A, v/sub ⊥//v/sub Z/=1.2, Δv/sub Z//v/sub Z/=7%, axis-encircling electron beam from a Northrop Grumman cusp gun. The single-stage amplifier is predicted by a large-signal simulation code to generate 50 kW at 30 GHz with 20% efficiency, 32 dB saturated gain and 3% constant-drive bandwidth.