Lee Kanghyeok, Hong Ha Young, Lee Wonwoo, Jo Semin, Park Hong Soo, Yang Junhyuk, Park Changkun, Lee Hojin, Hong Sun K
Department of Information Communication Convergence Technology, Soongsil University, Seoul, 0678, Korea.
School of Electronic Engineering, Soongsil University, Seoul, 0678, Korea.
Sci Rep. 2022 Jul 14;12(1):12015. doi: 10.1038/s41598-022-16037-1.
A broadband metasurface flat lens is proposed as a polarization-independent wideband superstrate for wave focusing and gain enhancement at Ka-band. The proposed metasurface structure consists of four metal layers and is designed with diagonally symmetric unit cells to accommodate both the vertical and horizontal polarizations. The focusing ability of the proposed metasurface flat lens is validated via simulation and measurement, where normally incident plane waves are shown to be enhanced by up to 11 dB as a result of wave focusing. Also, the radiation gain enhancement due to the proposed metasurface flat lens is demonstrated via simulation and measurement, where a gain enhancement of up to 10.5 dB is achieved. The results show that the proposed structure maintains the wave focusing and gain enhancement characteristics over a bandwidth of 28-32 GHz. Furthermore, to demonstrate the utility of the proposed metasurface for circular polarization (CP), the gain enhancement of a CP patch antenna as a result of implementing the proposed metasurface as a superstrate is demonstrated via simulation and measurement. It is shown that the proposed metasurface superstrate provides a CP gain enhancement of nearly 10 dB.
提出了一种宽带超颖表面平板透镜，作为一种在Ka波段用于波聚焦和增益增强的与偏振无关的宽带覆盖层。所提出的超颖表面结构由四个金属层组成，并采用对角对称的单元结构进行设计，以兼顾垂直极化和水平极化。通过仿真和测量验证了所提出的超颖表面平板透镜的聚焦能力，其中，由于波聚焦，垂直入射的平面波被增强了高达11dB。此外，通过仿真和测量证明了所提出的超颖表面平板透镜带来的辐射增益增强，实现了高达10.5dB的增益增强。结果表明，所提出的结构在28-32GHz带宽内保持了波聚焦和增益增强特性。此外，为了证明所提出的超颖表面对圆极化（CP）的效用，通过仿真和测量展示了将所提出的超颖表面作为覆盖层应用于CP贴片天线时带来的增益增强。结果表明，所提出的超颖表面覆盖层提供了近10dB的CP增益增强。
