A submillimeter-wave gyroklystron: Theory and design

New elements of the theory and a preliminary design for a pulse/continuous- wave 360-GHz gyroklystron are presented. Issues germane to very high-freque ncy operation of gyroklystron amplifiers, including drive power and limits on cavity Q, are discussed. A specific two cavity design is described, That device had a gain of 33 dB and a beam extraction power of 1 kW with an ele ctronic efficiency of 8% and a power output of 700 W after taking into acco unt Ohmic losses. To produce fast-rising pulses, the beam velocity ratio wa s varied via the modulating anode of a magnetron injection gun, A design fo r an electron gun through which reduction of the output signal by -50 dB wa s achieved by a 400-V modulation is given. The input coupler, cavities, ele ctron gun, collector, output coupling optics and collector are described. I n addition, issues concerning the fabrication of the high precision, simila r to2-mm diameter cavities are discussed.