Frequency hopping millimeter-wave reflectometry in ASDEX upgrade

Journal Article · Sun Oct 15 04:00:00 EDT 2006 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.2235206· OSTI ID:20861281

Cupido, L; Graca, S; Conway, G D; Manso, M; Serra, F ^[1]

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1. Centro de Fusao Nuclear (CFN), Associacao EURATOM/IST, Instituto Superior Tecnico, Avenida Rovisco Pais, P-1049-001 Lisbon (Portugal)

Millimeter-wave reflectometers for performing density fluctuations have traditionally used either tunable fixed frequency (heterodyne and homodyne) systems or multichannel fixed frequency arrangements. Only recently novel systems were brought into operation with the ability to hop from one frequency to another over a large bandwidth, during each plasma discharge, while retaining the quality of fixed frequency phase locked sources. The new broadband fast hopping millimeter-wave reflectometer incorporates frequency synthesizers for both plasma signal and local oscillators, and the receivers are heterodyne producing full phase/amplitude outputs. Two identical systems were recently installed in (ASDEX upgrade tokamak - IPP-MPG Germany) covering the Q band (33-50 GHz) and the V band (50-75 GHz). In the present article the system is described and the particular implementation on ASDEX, using monostatic antenna system, is presented showing the possibility of correlation studies in fully optimized antenna scenarios. With both Q and V channels in operation it was possible to devise several operation schemes that are described here and a result showing the radial localization of magnetohydrodynamic activity is also presented.

• OSTI ID: 20861281
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 10 Vol. 77; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ANTENNAS
ASDEX TOKAMAK
FLUCTUATIONS
GHZ RANGE 01-100
MAGNETOHYDRODYNAMICS
OPERATION
PLASMA
PLASMA CONFINEMENT
PLASMA DENSITY
PLASMA DIAGNOSTICS
SIGNALS