W-band millimeter-wave back-scattering system for high wavenumber turbulence measurements in LHD
نویسندگان
چکیده
A 90 GHz W-band millimeter-wave back-scattering system is designed and installed for measuring electron scale turbulence (k??s ? 40). metal lens relay antenna used in-vessel beam focusing, a diameter of less than 40 mm achieved in the plasma core region. This can be steered at an angle 159° ± 6°, which almost covers radius. The estimated size scattering volume ?105 edge 135 core, respectively. 60 m corrugated waveguide to achieve low transmission loss ?8 dB. heterodyne detection circuits with probing power modulation distinguish scattered signal from background noise.
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ژورنال
عنوان ژورنال: Review of Scientific Instruments
سال: 2021
ISSN: ['1089-7623', '1527-2400', '0034-6748']
DOI: https://doi.org/10.1063/5.0043474