幅相同调的吸波-对消雷达散射截面减缩超表面设计  

Absorption and cancellation radar cross-section reduction metasurface design based on phase-and amplitude-control

作　　者：袁方 毛瑞棋 高冕 郑月军 陈强[1] 付云起[1] Yuan Fang;Mao Rui-Qi;Gao Mian;Zheng Yue-Jun;Chen Qiang;Fu Yun-Qi(College of Electronic Science and Technology,National University of Defense Technology,Changsha 410073,China)

机构地区：[1]国防科技大学电子科学学院,长沙410073

出　　处：《物理学报》2022年第8期90-99,共10页Acta Physica Sinica

基　　金：国家自然科学基金青年科学基金(批准号:61801485,61901492,61901493)资助的课题~~。

摘　　要：更宽的工作频带和更低的雷达散射截面(radar cross section,RCS)一直是低可探测领域研究的热点,然而这两者往往难以兼顾.鉴于此,本文提出了一种幅相同调的吸波-对消RCS减缩超表面,通过在宽带范围内同时设计两个单元的反射相位和反射幅度,使目标RCS在空间域和能量域分别获得10 d B以上减缩,从而通过叠加获得20 d B以上的宽带RCS减缩.仿真和实验结果表明,在两种极化下,幅相同调的吸波-对消RCS减缩超表面可以在6.10—12.15 GHz频带范围内获得20 d B以上的RCS减缩效果,同时10 d B减缩带宽为4.3—14.2 GHz.所设计的超表面具有减缩幅度大、减缩频带宽、质量轻、单层结构、极化稳定性好、柔性易共形等优点,有望为低可探测材料研制以及低可探测装备性能提升提供新的技术途径.Wider band and deeper radar cross section(RCS)reduction by lower profile is always a very noticeable subject in stealth material researches.Most of researchers have designed and measured the RCS reduction bandwidth with 10 dB standard,that is,the return energy is reduced by 90%.In this paper we present a dualmechanism method to design a single-layer absorptive metasurface with wideband 20-dB RCS reduction by simultaneously combining the absorption mechanism and the phase cancellation mechanism.Firstly,the impedance condition for 20-dB RCS reduction is theoretically analyzed considering both the absorption and the phase cancellation based on the two unit cells,and the relationship between the surface impedance and the reflection phase/amplitude is revealed.According to these analyses,two unit cells with absorption performance and different reflection phases are designed and utilized to realize the absorptive metasurface.Then,we simulate the plane case and the cylinder case with the designed flexible metasurface and compare them with the counterparts with equal-sized metal.Finally,the sample is fabricated and characterized experimentally to verify the simulated results.Both numerical and experimental results show that the 7-mm-thick single-layer absorptive metasurface features a wideband 20-dB RCS within 6.10–12.15 GHz(66%).Our designed metasurface features wideband,20-dB reduction,polarization insensitivity,light weight and flexible,promising great potential in real-world low-scattering stealth applications.

关 键 词：雷达散射截面减缩超表面 幅相同调 吸波 相位对消 

分 类 号：TN957[电子电信—信号与信息处理]