Experimental study of efficiency optimization in a three-cavity gyroklystron amplifier

Author

Park, Gun-Sik ; Granatstein, Victor L. ; Park, S.Y. ; Armstrong, Carter M. ; Ganguly, Achintya K.

Author_Institution

Omega-P Inc., New Haven, CT, USA

Volume

20

Issue

3

fYear

1992

fDate

6/1/1992 12:00:00 AM

Firstpage

224

Lastpage

231

Abstract

An experimental study quantifying the effects of both penultimate cavity tuning and magnetic field profiling on the saturated efficiency of a three-cavity gyroklystron amplifier has been performed at a frequency of 4.5 GHz. As predicted by theory, it is observed that the penultimate cavity detuning in the gyroklystron is in the opposite direction from a conventional klystron for enhanced efficiency operation. This is a result of the opposite energy dependence of the bunching mechanism for the two interactions. Magnetic field profiling has also been shown to have a very strong effect on the amplifier efficiency, both through beam loading effects in detuning the penultimate cavity and through enhanced energy extraction in the output cavity. The measured efficiency of the gyroklystron is observed to improve from 5% to 21% by profiling the magnetic field along the device, and then from 21% to 29% by penultimate cavity detuning with an optimized magnetic field profile

Keywords

cavity resonators; gyrotrons; klystrons; magnetic fields; microwave amplifiers; tuning; 4.5 GHz; 5 to 29 percent; beam loading effects; bunching mechanism; efficiency optimization; enhanced energy extraction; magnetic field profiling; penultimate cavity tuning; saturated efficiency; three-cavity gyroklystron amplifier; Electromagnetic heating; Frequency; Gain; Klystrons; Linear accelerators; Magnetic field measurement; Microwave devices; Power amplifiers; Power generation; Tuning;

fLanguage

English

Journal_Title

Plasma Science, IEEE Transactions on

Publisher

ieee

ISSN

0093-3813

Type

jour

DOI

10.1109/27.142823

Filename

142823