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DOE OSTI · 1619613

Metasurface-based ultra-lightweight high-gain off-axis flat parabolic reflectarray for microwave beam collimation/focusing

Silva, Sinhara R.·Rahman, Abdur·de Melo Kort-Kamp, Wilton·Rushton, Jeremiah J.·Singleton, John·Taylor, Antoinette J.·Dalvit, Diego A. R.·Chen, Hou-Tong·Azad, Abul K.
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Abstract

Abstract Ultra-lightweight deployable antennas with high-gain are pivotal communication components for small satellites, which are intrinsically constrained in size, weight, and power. In this work, we design and demonstrate metasurface-based ultra-lightweight flat off-axis reflectarrays for microwave beam collimation and focusing, similar to a parabolic dish-antenna. Our ultra-thin reflectarrays employ resonators of variable sizes to cover the full 2 π phase range, and are arranged on the metasurface to realize a two-dimensional parabolic focusing phase distribution. We demonstrate a 30° off-axis focusing reflector that exhibits a measured gain of 27.5 dB at the central operating frequency of 11.8 GHz and a 3 dB directionality < $$\pm $$ ± 1.6°. Furthermore, we carry out full-wave simulations of the reflectarray, showing high gain of the beam focusing/collimation functionality, in good agreement with measurements. The demonstrated reflectarrays will enable low-cost, lightweight, and high-gain deployable transceivers for small-satellite platforms.

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42 ENGINEERINGengineeringmaterials sciencephysicsreflectarray, metasurfaces

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Silva, Sinhara R., Rahman, Abdur, de Melo Kort-Kamp, Wilton, Rushton, Jeremiah J., Singleton, John, Taylor, Antoinette J., Dalvit, Diego A. R., Chen, Hou-Tong, Azad, Abul K.. 2019-12-12. Metasurface-based ultra-lightweight high-gain off-axis flat parabolic reflectarray for microwave beam collimation/focusing. https://doi.org/10.1038/s41598-019-55221-8

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