CIRCUIT ASPECTS OF THE NRL/INDUSTRIAL 94 GHz GYROKLYSTRON AMPLIFIER

Abstract

Abstract A wide bandwidth, high average power W-band gyroklystron amplifier is currently under cooperative development by NRL, Litton Electron Devices, and Communication and Power Industries. The amplifier circuit is comprised of 4 stagger-tuned cavities operating in the fundamental TE 011 circular cavity mode. The input coupler is the first cavity of the circuit and must exhibit reasonable coupling strength between the TE 10 mode in rectangular waveguide and the desired TE 011 circular cavity mode over a better than 600 MHz bandwidth centered at 93.4 GHz, with high TE 01 mode purity. A single WR-8 rectangular waveguide drives a combined coaxial/cylindrical cavity system. The coaxial cavity resonating in the TE 411 mode is tightly coupled to the cylindrical cavity, excited to resonate in the TE 011 mode. The rf magnetic field couples the cavities through 4 azimuthally spaced apertures