Overmoded abrupt transition TE{sub 021} cavities for a 100 MW second harmonic gyroklystron

• Main Authors: Castle, M., Lawson, W., Anderson, J.P., Saraph, G.P., Stattel, M., Hogan, B., Granatstein, V.L., Reiser, M.
• Format: Conference Proceeding
• Language: English
• Subjects: CAVITY RESONATORS; COMPUTER-AIDED DESIGN; ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; HARMONIC GENERATION; MICROWAVE AMPLIFIERS; NUMERICAL ANALYSIS
• ISSN: 0730-9244; 2576-7208

Two overmoded, coaxial, abrupt transition cavities have been designed and are being built and experimentally cold tested at the University of Maryland. They are both designed to operate in the TE{sub 021} mode at 17.136 GHz. They are to be installed in the microwave circuit of a 3-cavity, 100 MW, 1 {micro}s pulse length, coaxial gyroklystron amplifier in the near future. The first cavity will serve as a bunching cavity. It is located near the center of the dielectrically loaded drift region of the gyroklystron. The cavity was designed with a scattering matrix code. After the geometry was selected, simulations with a linear stability code outlined criteria for the cavity`s stable operation. Finally a finite element code that can include lossy dielectric media (HFSS) was used to verify the findings of the scattering matrix code. Experimental cold testing will be completed at the time of presentation, and these results along with the theoretical work will be detailed. The second cavity is an output cavity whose microwave energy is extracted axially from a radial lip. This cavity was designed with the scattering matrix code to have a Q of 320. Further numerical analysis shows this to be stable within experimental current values (up to 800 A). Along with these results, simulations of the circuit operation and current status of the second harmonic experiment will be reported.