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arXiv · 2501.15997

Confocal Ellipsoidal Reflectors with Phased Array Vivaldi Antenna Source for Imaging Systems

Mohammad Hossein Koohi Ghamsari·Mahyar Mehri Pashaki·Mehdi Ahmadi-Boroujeni
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Abstract

In this paper, an on-axis dual-reflector confocal ellipsoidal structure is presented for near-field imaging systems. In the proposed structure, the backscattered electromagnetic wave problem, known as the blockage effect, is reduced considerably using an elaborate design of the sub-reflector and precise alignment of the reflectors. The proposed geometry is analyzed, followed by a design example for the stand-off distance of 2 m. The blockage reduction characteristic is verified using ray-tracing simulation. Next, the scanning performance of the structure is investigated utilizing a Vivaldi phased array antenna as the source designed at the central frequency of 28 GHz. The full-wave simulations proved a field-of-view (FoV) of approximately 40 cm. Furthermore, tuning the proposed reflectors configuration standoff distance is examined with a point source. The ray-tracing simulations showed that stand-off distance can be easily changed up to tens of centimeters with just a few centimeters of source point lateral displacement.

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Mohammad Hossein Koohi Ghamsari, Mahyar Mehri Pashaki, Mehdi Ahmadi-Boroujeni. 2025-01-27. Confocal Ellipsoidal Reflectors with Phased Array Vivaldi Antenna Source for Imaging Systems. https://doi.org/10.23919/eucap63536.2025.10999938

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