MTX/ELF II microwave power measurements and calibration for the 2 GW, 140 GHz, ELF II free-electron laser

Author

Ferguson, S.W. ; Stever, R. ; Throop, A. ; Felker, B. ; Franklin, R.

Author_Institution

Lawrence Livermore Nat. Lab., CA, USA

fYear

1989

fDate

2-6 Oct 1989

Firstpage

145

Abstract

Techniques for measuring the power and frequency of the Electron Laser Facility (ELF)-II free-electron laser (FEL) used for plasma heating experiments on the Microwave Tokamak Experiment (MTX) have been developed. A multichannel 140-GHz receiver capable of measuring FEL power levels from 10 mW to 0.1 μW within an accuracy of ±1 dB and with a 50-dB dynamic range and a 2-ns response time has been designed. By using calibrated attenuators, it is possible to measure power levels from 10 GW to 0.1 μW. The microwave output of the FEL in a microwave load tank is sampled by using WR-8 or WR-28 stub waveguide antennas. Microwave turning mirrors are used to guide the microwave beam down an evacuated beam tube to the MTX. Stub, WR-8, fundamental-mode waveguide antennas are used for beam detection on the microwave turning mirrors

Keywords

calibration; free electron lasers; frequency measurement; fusion reactor ignition; fusion reactor operation; fusion reactor theory and design; laser variables measurement; microwave measurement; plasma diagnostic techniques; plasma radiofrequency heating; plasma toroidal confinement; power measurement; 140 GHz; 2 GW; Electron Laser Facility; MTX/ELF II microwave power measurements; Microwave Tokamak Experiment; WR-28 stub waveguide antennas; WR-8; beam detection; calibrated attenuators; calibration; evacuated beam tube; free-electron laser; fundamental-mode waveguide antennas; microwave beam; microwave load tank; microwave output; microwave turning mirrors; plasma heating experiments; Calibration; Electromagnetic heating; Free electron lasers; Geophysical measurement techniques; Ground penetrating radar; Masers; Microwave antennas; Plasma measurements; Power lasers; Power measurement;

fLanguage

English

Publisher

ieee

Conference_Titel

Fusion Engineering, 1989. Proceedings., IEEE Thirteenth Symposium on

Conference_Location

Knoxville, TN

Type

conf

DOI

10.1109/FUSION.1989.102192

Filename

102192