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arXiv · 2608.08991

Active Hemispherical Metasurface Transmitarray Antenna for Wide-Angle 3D Beam Steering and Target Tracking

Somayeh Komeylian·Christopher Paolini
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Abstract

A stacked multilayer hemispherical graphene-based transmitarray antenna operating at 250 GHz is developed to achieve wide-angle 3D beam steering. This work presents the first fully automated CST Studio Suite macro for constructing the multilayer hemispherical geometry and configuring 121 independently tunable graphene sectors. Numerical results confirm that the integration of voltage-controlled graphene sectors with FCC gold patches enables wide-angle beam steering, achieving an elevation scanning range of -78{\deg} to 78{\deg} in {\theta} and full 360{\deg} azimuthal coverage while maintaining stable radiation characteristics and broadband impedance matching (|S11| < -10 dB) with a relative bandwidth of 40%. The antenna achieves a directivity range of 11.38 - 14.72 dBi and an SLL range of -6.8 to -9.8 dB across all investigated steering directions. It also maintains high antenna efficiencies from 71% to 80% with a 5% degradation due to imperfections across the entire scanning range, making it a promising candidate in practical moving-target-tracking applications.

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Somayeh Komeylian, Christopher Paolini. 2026-08-10. Active Hemispherical Metasurface Transmitarray Antenna for Wide-Angle 3D Beam Steering and Target Tracking. https://arxiv.org/abs/2608.08991

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