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arXiv · 2611.07655

A Conformal Transmit-Reflect Array Enabling Multifunctional Bidirectional Beam Switching for Emergency Communication System

Yifei Liu·Fan Qin·Chao Gu·Wenchi Cheng·Steven Gao
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Abstract

This article presents a conformal transmit-reflect array (CTRA) that enables bidirectional multibeam switching through a single metasurface aperture for emergency communication applications. To realize reconfigurable bidirectional beam switching, a transmit-reflect integrated element (TRIE) is developed by combining a polarization-selective transmissive structure with a complementary-symmetric reflective structure. The proposed element enables independent control of the cross-polarized transmission and reflection phases while exhibiting stable performance under oblique incidence. To support practical conformal implementations, a geometrical-optics-based phase compensation method is applied to cylindrical geometries, enabling effective wavefront control across the conformal aperture. By incorporating a polarization-switchable feed array (PSFA), multifunctional beam switching is achieved in the forward, backward, and bidirectional operating modes. The PSFA is configured as a nonuniform curved linear array near the focal region, enabling feed-selective beam switching within $\pm 30^\circ$ in both the $+z$ and $-z$ directions through selective excitation of the corresponding feed elements. The full-wave simulation results agree well with the measurements. The proposed CTRA achieves peak gains of 24.1 and 24.8 dBi in the forward and backward modes, respectively. The maximum aperture efficiencies in the forward and backward operating states are 28.4$\%$ and 33.4$\%$. These results demonstrate the effectiveness and flexibility of the proposed CTRA, making it a promising candidate for adaptive emergency communication systems.

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Yifei Liu, Fan Qin, Chao Gu, Wenchi Cheng, Steven Gao. 2026-11-05. A Conformal Transmit-Reflect Array Enabling Multifunctional Bidirectional Beam Switching for Emergency Communication System. https://arxiv.org/abs/2611.07655

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