微波段超构表面对电磁波波前的调控研究

文章回顾总结了本课题组近期关于微波段超构表面的研究进展。首先推导了单层超构表面的透射效率极限值,并设计实现了对交叉圆极化电磁波波前的有效人工调控。进一步基于等效滤波器的理论模型,推导了多层超表面的基本结构特性,在此基础上设计了能够分别工作于线极化及圆极化入射波条件下的多层超构透镜,实现了微波涡旋波束的高效激发,以及对正交圆极化的内在对称性进行人为解耦等多重波前调控。经过一系列的仿真分析和实验验证,我们所设计的微波段单层、多层超构表面均可产生符合预期理论设计的调控结果。这些研究进展为电磁波调控器件的平面化提供了有效的理论依据,加快了超构表面在无线通信技术领域的应用和发展。

Microwave Meta-lens for Electromagnetic Wavefront Manipulation

In this paper, recent works on microwave meta-lens for artificially manipulating electromagnetic wavefront are reviewed. Firstly, the limitation of transmission efficiency of single-layer metasurface is theoretically calculated, and the cross-circularly-polarized transmitted wave are utilized to generate versatile functionalities. Furthermore, the basic properties of multi-layer meta-structure are derived from the equivalent filter model in microwave regime. Based on this, meta-lenses for linear and circular electromagnetic wave manipulation are proposed, which can produce vortex beam carrying orbital angular momentum (OAM) with high efficiency and decouple the inherence symmetric restriction orthogonal between circular polarizations. Demonstrated by a series of theoretical simulation and experimental measurements, the proposed meta-lenses can effectively perform the preset functional wavefronts. These schemes provide a promising approach for designing planar equipment, which can be widely applied in wireless communication systems.