基于超表面的双频段宽带极化转换器设计

Design of dual and broadband polarization converter based on metasurface

极化转换器在卫星通信、雷达探测等领域具有重要用途,提出一种基于改进工字型贴片结构的双波段宽带超表面极化转换器。引入矩形贴片形成多谐振峰,有效提升了极化转换器的带宽。理论上分析了该超表面的极化转换原理,实验验证了仿真结果。仿真和测试结果表明该超表面在两个频段(4.3~4.8 GHz,7.3~17.1 GHz)内可以高效地将线极化入射波转换为交叉极化的反射波,高频段的相对带宽达到82%,同时在三个谐振点其极化转换效率接近100%。对比现有的极化转换器,具有结构简单、带宽大的优点。

Polarization converter has important applications in satellite communication and radar detection.Here a linear dual and broad band polarization converter was proposed based on improved I-shaped metasurface.The bandwidth of the metasurface could be effectively improved by introducing coupling between the I-shaped and rectangular patch.The mechanism of the polarization conversion by the metasurface was analyzed by theoretical calculation,numerical simulations and experiments,which were all congruent.Full wave simulation and experimental results show that the polarization converter can convert x or y-polarized incident wave to its cross polarized wave in two frequency bands(4.3-4.8 GHz,7.3-17.1 GHz)with conversion efficiency greater than 90%.In addition,the higher frequency band features an ultra-wide relative bandwidth of 82%.The polarization conversion ratio(PCR)at the three electromagnetic resonant points almost approaches 100%.The proposed polarization converter has advantages of simple design and broadband operation in contrast to previously reported approaches.