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DOE OSTI · 22308928

Adaptive array technique for differential-phase reflectometry in QUEST

Hanada, K.·Zushi, H.·Nagata, K.·Mishra, K.·Itado, T.·Akimoto, R.·Yamamoto, M. K.
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Abstract

A Phased Array Antenna (PAA) was considered as launching and receiving antennae in reflectometry to attain good directivity in its applied microwave range. A well-focused beam was obtained in a launching antenna application, and differential-phase evolution was properly measured by using a metal reflector plate in the proof-of-principle experiment at low power test facilities. Differential-phase evolution was also evaluated by using the PAA in the Q-shu University Experiment with Steady State Spherical Tokamak (QUEST). A beam-forming technique was applied in receiving phased-array antenna measurements. In the QUEST device that should be considered as a large oversized cavity, standing wave effect was significantly observed with perturbed phase evolution. A new approach using derivative of measured field on propagating wavenumber was proposed to eliminate the standing wave effect.

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46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGYANTENNASBEAM PROFILESEVALUATIONMEASURING INSTRUMENTSMICROWAVE RADIATIONREFLECTIONSTANDING WAVESTEST FACILITIESTESTINGTOKAMAK DEVICES

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Hanada, K., Zushi, H., Nagata, K., Mishra, K., Itado, T., Akimoto, R., Yamamoto, M. K.. 2014-11-15. Adaptive array technique for differential-phase reflectometry in QUEST. https://doi.org/10.1063/1.4891710

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