摘要
提出了一种具有宽带雷达散射截面缩减特性的1 bit编码超表面。该超表面由两种单元组成:"0"单元和"1"单元,其反射相位差在很宽的频段范围内接近180?。通过对这两种基本单元的空间排布进行编码设计,使入射电磁波发生漫反射,可以实现雷达散射截面的缩减。全波仿真结果表明,在垂直入射的情况下,相对于同尺寸的金属板,该超表面可在10-20.5GHz的宽频段内基本实现10 d B以上雷达散射截面缩减,最大缩减量达到20.8 d B。该超表面具有低剖面、重量轻、频带宽等特点,因而在隐身新技术和新材料方面具有很大的应用潜力。
In this paper, a novel 1 bit coding metasurface is proposed and applied to broadband radar cross section(RCS) reduction. The metasurface is composed of "0" and "1" elements. The reflection phase difference of the two elements is about 180 ? in broad frequency band. By designing the coding sequences of the coding metasurface, broadband RCS reduction is obtained as a result of the diffuse reflection. Full-wave simulation results show that the RCS reduction more than 10 d B for coding metasurface can be achieved in a wide frequency range from 10-20.5 GHz with respect to the equal-sized PEC ground plane at normal incidence. The maximum reduction is 20.8 d B. The proposed metasurface has the advantages of low profile, light weight and broad band, which shows great potential applications in novel stealth technologies and materials.
引文
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