极薄宽角度平面超材料吸波体仿真与实验验证

Simulation and experiment demonstration of an ultra-thin wide-angle planar metamaterial absorber

仿真和实验验证了厚度极薄的平面结构超材料吸波体,该吸波体采用加载交指电容的耶路撒冷十字结构,通过增加单元间的耦合电容显著降低了其工作频率.测试结果表明,该超材料吸波体在1.58 GHz,吸收率峰值为88.48%,其厚度为2 mm,约为1/95工作波长,吸波体的单元尺寸为11 mm,约为1/17工作波长.此外,通过金属通孔将耶路撒冷十字结构与金属底板相连接,使其对斜入射横电和横磁极化电磁波具有宽角度吸收特性,在60时依然具有较高的吸收率,且吸收峰频率几乎不发生偏移,从而使其更具实用价值.

In this paper, we present the simulation and experimental validation of an ultra-thin planar metamaterial absorber, which is composed of Jerusalem crosses loaded by interdigital capacitors. By increasing the coupling capacitance between adjacent unit cells, we are able to significantly lower the operating frequency of the absorber. The measured results indicate that the metamaterial absorber achieves a peak absorption of 88.48%at 1.58 GHz. The total thickness and the unit cell size of the absorber are 2 mm and 11 mm, which are approximately 1/95 and 1/17 of the working wavelength, respectively. Additionally, the Jerusalem crosses and the metallic ground plane are connected by vias, which makes the metamaterial absorber achieve wide-angle absorption for both transverse electric and transverse magnetic polarizations electromagnetic wave. The absorptivity is still large even at the incident angle of 60？, and the frequency of the absorption peak almost has no deviation, which makes the absorber more practical.