一种产生双频涡旋电磁波的反射型超表面

A Reflective Metasurface for Generating Dual-Band Vortex Electromagnetic Waves

设计了一款双频涡旋电磁波超表面。该超表面由加载传输线的双对称C型环超表面单元构成,通过改变单元内外加载相位延迟线的长度,两个频段都能达到360°的相位覆盖范围,且单元内部耦合较小,可独立控制相位变化。基于此单元,设计了工作在8 GHz和18 GHz的13×13单元的双频反射型超表面。仿真结果表明,设计的超表面在8 GHz和18 GHz处均生成了l=+1模式的OAM涡旋电磁波,在8 GHz增益达到了16.2 dBi,在18 GHz增益达到了21.6 dBi,实现了良好的双频OAM涡旋波束特性。

In this paper,a dual-band vortex electromagnetic wave metasurface is designed.The metasurface consists of a dual-symmetric C-ring unit cell with transmission lines.By varying the length of the phase delay line loaded inside and outside the unit cell,a phase coverage of 360°can be achieved at both frequencies,Moreover,the phase change can be controlled independently with less coupling inside the unit cell.Based on the unit cell,a dual-band reflective metasurface with 13×13 unit cells operating at 8 GHz and 18 GHz is designed.Simulation results show that the designed metasurface generates OAM vortex waves of l=+1mode at both 8 GHz and 18 GHz,with a gain of 16.2 dBi at 8 GHz and 21.6 dBi at 18 GHz,achieving good dual-band OAM vortex beam characteristics.