双层超表面互补增强宽频广角复合吸波体  

Ultrawideband and High Absorption Composite Absorber Enabled by Double Layers of Metasurface Complementary Enhancement Design

作　　者：麻晢乂培 姜超[1,2] 刘妍琼[1,2] 黎嘉乐 MA Zhe-yi-pei;JIANG Chao;LIU Yan-qiong;LI Jia-le(Institute of Powder Metallurgy Research,Central South University,Changsha,Hunan 410083,China;State Key Laboratory of Powder Metallurgy,Changsha,Hunan 410083,China)

机构地区：[1]中南大学粉末冶金研究院,湖南长沙410083 [2]粉末冶金国家重点实验室,湖南长沙410083

出　　处：《电子学报》2024年第8期2668-2678,共11页Acta Electronica Sinica

基　　金：湖湘青年科技创新人才项目(No.2021RC3003);国防科技基础加强计划子课题(No.2022-JCJQ-ZD-01-1)。

摘　　要：本文提出了一种基于双层超表面的多层复合吸波体的设计方法,设计的吸波体包含两层核心超表面功能层、顶层吸收增强蒙皮和数层支撑介质层,两层超表面Ⅰ和Ⅱ的结构单元分别为加载贴片电阻的异形金属片和加载贴片电阻的六边形金属环,蒙皮为玻璃纤维层压板,支撑介质为PMI泡沫.仿真结果表明,反射系数低于-10 dB的吸波频带覆盖范围为2.80~23.64 GHz,低于-20 dB的吸波频带覆盖范围为3.56~22.56 GHz.测试结果表明,反射系数低于-10 dB的频带为2.36~23.87 GHz;-20 dB吸波频带为3.17~23.16 GHz.仿真和测试所得反射系数曲线具有良好的一致性,验证了该设计方法的有效性.仿真和测试结果表明,50°斜入射的-10 dB反射系数频带与垂直入射时基本保持一致,起始和终止频率的偏移量小于0.8 GHz;进一步地,斜入射角为60°时,反射系数低于-10 dB的相对带宽最大可达141.8%,表明本研究所设计的复合吸波体具有宽角域入射稳定特性.此外,本文研究了该复合吸波体宽频广角强吸收的相关机理以及主要结构参数对吸波性能的影响,结果表明顶层蒙皮在超宽带范围内可提升吸波率0.2(1.0代表100%吸波),两层超表面吸波频带的互补增强设计能够明显改善其斜入射角度稳定性.In this study,a design method of multilayer structure composite absorber based on double layers of meta⁃surface is proposed.The designed composite absorber consists of two layers of metasurface,top absorption enhanced skin and several support dielectric slabs.The unit cells of metasurfaceⅠandⅡare separately irregular-shaped metal patches connected by chip resistors and hexagonal metal rings loaded with chip resistors;the top absorption enhanced skin is a fiber⁃glass enforced epoxy laminate;support dielectric slabs adopt PMI foam.The simulation results indicate that the absorption frequency bands with reflection coefficients below-10 dB and-20 dB are 2.80~23.64 GHz and 3.56~22.56 GHz,respec⁃tively.The measurement results show that,the absorption frequency bands with reflection coefficients below-10 dB and-20 dB are 2.36~23.87 GHz and 3.17~23.16 GHz,respectively;the reflection coefficient curves obtained by simulation and test have good consistency,which verifies the effectiveness of the design method.The simulation and test results show that the frequency band of-10 dB reflection coefficient at 50°oblique incidence is basically consistent with that at normal inci⁃dence,while the offset of start and stop frequencies is less than 0.8 GHz;further,the simulation and test results show that when the oblique incidence angle is 60°,the fractional bandwidth of the reflection coefficient below-10 dB is up to 141.8%,which indicates that the composite absorber designed in this study has the incidence stability in a wide angle range.In addition,the mechanism of ultrawideband and high absorption of the structure and the influence of the main structure pa⁃rameters are analyzed;the results demonstrate that the top absorption enhanced skin can improve absorptivity of the whole structure by up to 0.2(1.0 represents 100%absorption),and the complementary enhancement design of the two layers of metasurface absorption frequency bands can improve oblique incidence stability obviously.

关 键 词：吸波体 超表面 多层结构 超宽带 斜入射 

分 类 号：TN001[电子电信—物理电子学] TB34[一般工业技术—材料科学与工程]