Millimeter-wave high gain crossed-field amplifier

A millimeter-wave tube using a dual-slot anode circuit was tested under two different average output levels at a frequency of 34 GHz. The tube was operated with an output of 15.5 kW peak power, 140 W average power with a gain of 10 dB, and at 4 kW peak. 200 W average power at a gain of 8 dB. The enhance the RF gain levels of the device and to provide RF isolation, an RF circuit, introduced into the cathode, is contemplated. Basically, the RF drive power is applied directly to the cathode surface region where it is most effective in electron spoke formation. With the RF input fed to a delay line circuit on the cathode, RF gain of 28 dB has been achieved at S-band with no deterioration in power output or DC-to-RF conversion efficiency.<>