Abstract
An in-situ alignment system for beam waveguides based on an interferometric direction-finding antenna was investigated numerically and experimentally. The system consists of a reflector with four off-central positioned waveguide couplers in two directions. By nulling the difference of the power signals as well as the mixing signal from each coupler pair, spatial and angular alignments of a beam impinging on the mirror can be performed.
In this paper, the characteristics of such a mirror are presented, and the design of a prototype intended for use in an ECH transmission line at LHD is described. Low-power as well as high-power tests at a frequency of 82.7 GHz were carried out, and the results are discussed. The device shows a high performance in agreement with theory.
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Kasparek, W., Idei, H., Kubo, S. et al. Beam Waveguide Reflector with Integrated Direction-Finding Antenna for In-Situ Alignment. International Journal of Infrared and Millimeter Waves 24, 451–472 (2003). https://doi.org/10.1023/A:1022468412389
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DOI: https://doi.org/10.1023/A:1022468412389