基于共享孔径技术的低RCS电磁超构表面天线设计  

Low-RCS electromagnetic metasurface antenna based on shared-aperture technique

作　　者：李桐[1] 杨欢欢[1] 李奇[2] 廖嘉伟 高坤 季轲峰 曹祥玉[1] Li Tong;Yang Huan-Huan;Li Qi;Liao Jia-Wei;Gao Kun;Ji Ke-Feng;Cao Xiang-Yu(Information and Navigation College of Air Force Engineering University,Xi’an 710077,China;System Innovation Center of China Academy of Space Technology,Xi’an 710100,China)

机构地区：[1]空军工程大学信息与导航学院,西安710077 [2]中国空间技术研究院系统创新中心,西安710100

出　　处：《物理学报》2024年第12期159-169,共11页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:62371466,62171460,62203464);陕西省自然科学基础研究计划(批准号:2024JC-ZDXM-39,20220104,2020022);空间微波技术国家重点实验室基金(批准号:HTKJ2022KL504004)资助的课题。

摘　　要：提出一种基于共享孔径技术设计低雷达散射截面(radar cross section,RCS)电磁超构表面天线的新方法.该方法首先设计具有低RCS性能的超构表面,然后借鉴共享孔径技术思想,将超构表面和传统天线的辐射结构直接共享口径紧密排列,得到新型低RCS天线结构,并结合电流分析和局部结构修正,优化天线的辐射性能,最终同时实现天线的良好辐射和宽带低RCS性能.为了阐明该方法,基于极化旋转机理设计了一款低RCS超构表面,采用共享孔径思想和电流分析,得到了一款宽带低RCS超构表面天线,详细分析了该天线的工作机理与性能.结果表明:设计的天线在保证较好辐射的同时,实现了超宽带RCS减缩,提出的设计方法摒弃了从天线到低RCS天线的传统设计思路,通过逆向思维,将散射的优化问题转化为辐射的优化问题,不仅实现了天线与超构表面的一体化设计,还显著地降低了低RCS天线优化设计的难度,加速了天线优化进程.In this paper,a novel shared-aperture method of electromagnetic metasurface and antenna is proposed to obtain low radar-cross-section(RCS)performance.In this method,the low-RCS metasurface is first designed,then this metasurface is combined with traditional antenna to obtain novel low-RCS antenna based on sharedaperture technique.Besides,the analysis and corresponding local structure modification are also conducted to ensure that the antenna has good radiation performance while reducing broadband RCS.Using this method,a dual-layer polarization rotation unit cell is first proposed and its broadband working principle is investigated by both theoretical analysis and numerical comparison.Based on this unit cell,a broadband low-RCS metasurface is constructed.Then an initial shared-aperture metasurface antenna is obtained by substituting the middle cells in the metasurface with traditional patch antenna directly.Through careful analysis of surface current in radiation mode,the gain decrease of this metasurface antenna is revealed.On this basis,a finite removal strategy is put forward and some metasurface cells in the antenna are removed by using the electric current analysis.Consequently,an improved shared-aperture metasurface antenna is proposed.This improved antenna works in a frequency range from 6.3 to 7.48 GHz,which is slightly wider than the traditional patch antenna.Its gain is also higher than that of traditional antenna,with a maximum improvement of 1 dB.Meanwhile,the apparent RCS decreases from 6 to 16 GHz for any polarized incident wave,and the reduction peak is larger than 20 dB.Finally,fabrications and measurements are conducted.The measurement results and numerical calculations are in good agreement.The well-behaved radiation performance and broadband low-RCS property of this metasurface antenna verify the effectiveness of the proposed method.Unlike most of reported design methods of low-RCS antennas directly from traditional antennas,the proposed method adopts reverse thinking to transform scattering opt

关 键 词：电磁超构表面 天线 共享孔径技术 低雷达散射截面 

分 类 号：TN823[电子电信—信息与通信工程]