Design of an Ultra-wide Band Waveguide Transition for the Ex-vessel Transmission Line of ITER Plasma Position Reflectometry
Plasma position reflectometry for ITER requires interfaces between in-vessel and ex-vessel waveguides. An ultra broadband interface (15–75 GHz) was designed between moderately oversized rectangular waveguide (20 × 12 mm), operated in TE01 (i.e., tall waveguide mode), and circular corrugated waveguide, with 88.9-mm internal diameter, propagating HE11. The interface was designed both as a sequence of waveguide components and as a quasi-optical confocal telescope. The design and the simulated performance are described for both concepts. The latter one requires more space but has better performance, and shall be prototyped.
KeywordsPlasma diagnostics Reflectometry Waveguide components Quasi-optical components
We are grateful to an anonymous Referee for useful suggestions.
Work leading to this publication was partially funded by Fusion for Energy under Specific Grant Agreement F4E-FPA-375-SG05. This publication represents only the view of the authors and Fusion for Energy cannot be held responsible for any use that may be made of the information contained herein.
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