基于超构表面的高效宽带交叉极化转换器设计

Design of High-Efficiency Wideband Cross Polarization Convertor Based on Metasurface

基于近年来利用超构表面在调控电磁波极化状态方面的热度,应用超构表面设计了一种适用于微波频段的新型极化转换器,可以在比较宽的带宽内,将入射的线极化波高效地转换为其交叉极化的反射波,在四个频点附近转换效率甚至达到100%。在整个工作频带内,仿真和测试结果基本吻合,仿真得到极化转换效率高于90%,频带宽度为7.88-20.70 GHz,相对带宽达到了89.7%。理论上给出了极化转换器的设计原理,仿真确定了转换器谐振点的位置,分析了极化转换器工作的物理原理,实验验证了极化转换器的效果。所设计的极化转换超构表面在极化选择控制方面有重要应用。

The polarization state has turned into a hot issue to manipulate polarization state of electromagnetic wave by utilizing a metasurface recently. Under this circumstance,a new-type polarization convertor based on metasurface has been designed in microwave band. The proposed polarization convertor can convert a linearly polarized incident wave into its cross polarized reflective wave in a broad band and keep high efficiency,with the polarization conversion ratio even achieving100% at four different frequencies. The simulated and measured results agree well with each other in the entire frequency band. The simulated bandwidth of polarization conversion ratio over 90% is from 7.88 GHz to 20.70 GHz,with the relative bandwidth up to 89.7%. The principle of designing a polarization convertor is given theoretically. Then the resonant frequencies are determined and the physical mechanism of the polarization convertor is analyzed through simulation. Finally,the polarization convertor is fabricated and measured to verify the whole work. The proposed metasurface is potential in the application of selecting and controlling polarization state in microwave region.