Lor Chhunheng, Phon Ratanak, Lim Sungjoon
Intelligent Semiconductor Engineering, Chung-Ang University, Heukseok-Dong, Dongjak-Gu, Seoul, 06974 Republic of Korea.
School of Electrical and Electronic Engineering, Chung-Ang University, Heukseok-Dong, Dongjak-Gu, Seoul, 06974 Republic of Korea.
Microsyst Nanoeng. 2024 Mar 21;10:40. doi: 10.1038/s41378-024-00671-y. eCollection 2024.
Polarization conversion and beam scanning metasurfaces are commonly used to reduce polarization mismatch and direct electromagnetic waves in a specific direction to improve the strength of a wireless signal. However, identifying suitable active and mechanically reconfigurable metasurfaces for polarization conversion and beam scanning is a considerable challenge, and the reported metasurfaces have narrow scanning ranges, are expensive, and cannot be independently controlled. In this paper, we propose a reconfigurable transmissive metasurface combined with a scissor and rotation actuator for independently controlling beam scanning and polarization conversion functions. The metasurface is constructed with rotatable unit cells (UCs) that can switch the polarization state between right-handed (RHCP) and left-handed circular polarization (LHCP) by flipping the UCs to reverse their phase variation. Moreover, independent beam scanning is achieved using the scissor actuator to linearly change the distance between the UCs. Numerical and experimental results confirm that the proposed metasurface can perform beam scanning in the range of 28° for both the positive and negative regions of a radiation pattern (RHCP and LHCP beams) at an operational frequency of 10.5 GHz.
极化转换和波束扫描超表面通常用于减少极化失配,并将电磁波引导至特定方向,以提高无线信号的强度。然而,识别适用于极化转换和波束扫描的合适有源和机械可重构超表面是一项相当大的挑战,并且已报道的超表面扫描范围窄、成本高且无法独立控制。在本文中,我们提出了一种结合剪刀式和旋转致动器的可重构透射超表面,用于独立控制波束扫描和极化转换功能。该超表面由可旋转的单元结构(UC)构成,通过翻转UC以反转其相位变化,可在右旋圆极化(RHCP)和左旋圆极化(LHCP)之间切换极化状态。此外,使用剪刀式致动器线性改变UC之间的距离可实现独立的波束扫描。数值和实验结果证实,所提出的超表面在10.5 GHz的工作频率下,对于辐射方向图的正、负区域(RHCP和LHCP波束)均可在28°范围内进行波束扫描。