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Measurement of the density of magnetized fusion plasma using microwave reflectometry

Published online by Cambridge University Press:  19 January 2010

Jean-Claude Giacalone ,
Roland Sabot ,
Frédéric Clairet ,
Christine Bottereau  and
Diego Molina
Jean-Claude Giacalone*
Affiliation:
CEA, IRFM, F - 13108 Saint-Paul-lez-Durance, France.
Roland Sabot
Affiliation:
CEA, IRFM, F - 13108 Saint-Paul-lez-Durance, France.
Frédéric Clairet
Affiliation:
CEA, IRFM, F - 13108 Saint-Paul-lez-Durance, France.
Christine Bottereau
Affiliation:
CEA, IRFM, F - 13108 Saint-Paul-lez-Durance, France.
Diego Molina
Affiliation:
CEA, IRFM, F - 13108 Saint-Paul-lez-Durance, France.
*
Corresponding author: J-C Giacalone Email: jean-claude.Giacalone@cea.fr
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Abstract

About 25 years have elapsed since the first measurement by a FW-CW (called fast sweeping) reflectometer of the electronic density in magnetized fusion plasma. Substituting tube sources with solid-state components has resulted in a decrease of the sweeping time from the millisecond to the microsecond range. Based on voltage control oscillators and on active frequency multipliers, four profile reflectometers covering the range 33–155 GHz are in operation on Tore-Supra tokamak. Their originality is the use of one source for the launched and reference signal, although the detection is heterodyne. Indeed, a single side band modulator shifts the launched frequency ahead of frequency multipliers. With a sweeping time comparable to the plasma turbulence characteristic time the density profile is frozen. The density profile is then reliably measured with high radial and temporal resolution.

Keywords

Fusion plasma diagnosticReflectometryFM-CW millimeter radar
Type
Original Article
Information
International Journal of Microwave and Wireless Technologies , Volume 1 , Special Issue 6: 2009 National Microwave Days in France , December 2009 , pp. 505 - 509
Copyright
Copyright © Cambridge University Press and the European Microwave Association 2010

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References

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