基于超表面的多频带双极化转换器设计

Design of multiband dual-polarization converter based on metasurface

极化转换器在无线通信、雷达探测等众多工程领域有着广泛的应用,针对当前超宽带、多功能、高效率的应用需求,提出了一种双极化、多频带反射型极化转换器。基于超表面设计,该结构由顶层周期排列金属贴片、介质层和金属底板3部分组成。研究表明,对入射的线极化波,该结构在6.2—6.7 GHz、17.7—19.2 GHz、20.88—21.14 GHz 3个波段内实现极化转换率(polarization conversion ratio,PCR)高于90%的交叉极化转换;在7.12—16.68 GHz、19.47—20.67 GHz两个波段实现轴比(axial ratio,AR)低于3 dB的线圆极化转换。该设计具有结构简单、加工方便、能量损耗低等特点,在电磁波极化调控、微波器件设计等方面具有一定的理论与实用价值。

Polarization converter is widely used in many engineering fields such as wireless communication,radar detection and so on,aiming at the current application requirements of ultra-wideband,multi-function and high-efficiency,a dual-polarized,multi-band reflective polarization converter is proposed.Based on the metasurface,the structure is composed of three parts:metallic patch arranged periodically in top layer,dielectric layer and metallic plate in bottom layer.The research shows that for the incident linear polarization wave,the structure can realize cross-polarization conversion in the three bands of 6.2—6.7 GHz,17.7—19.2 GHz,20.88—21.14 GHz with a polarization conversion ratio(PCR)of over 90.It can realize linear-circular polarization conversion in the two bands of 7.12—16.68 GHz,19.47—20.67 GHz with a axial ratio(AR)of below 3 dB.This design has the characteristics of simple structure,convenient manufacture and low-energy consumption,it has certain theoretical and practical value in electromagnetic wave polarization controlling and microwave device designing and so on.