Effects of Deformation of Main Reflector of Double Reflector Spherical Antenna on Its Aperture Field - ROT-54/2.6 Antenna Case
DOI:
https://doi.org/10.26636/jtit.2026.2.2528Keywords:
antenna, radio-optical telescope, ROT-54/2.6, terrestrial laser scanningAbstract
The aim of this study is to model the impact of main reflector deformations in a double-reflector spherical antenna system on the phase distribution of the electromagnetic field across the aperture and the associated gain loss. The study focuses on the antenna of the ROT-54/2.6 radio-optical telescope (Herouni radio telescope) - a spherical double-reflector system with a fixed primary reflector with a 54 m diameter, composed of 3738 panels. An analytical model is developed to evaluate phase distortions induced by deviations from the spherical geometry. The model computes local phase shifts across the aperture and predicts gain degradation using Ruze's formula which relates the RMS surface error to efficiency losses. This approach is important for pre-alignment procedures and functional restoration of the antenna, enabling geometry corrections prior to full-scale observations. Based on terrestrial laser scanning (TLS) data, the methodology allows for a quantitative assessment of structural phase errors and corresponding gain degradation, confirming its suitability for practical diagnostics of large reflector systems.
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Copyright (c) 2026 Arevik Sargsyan, Narek Hambardzumyan
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