基于平面螺旋结构的极化不敏感超材料吸波体研究

Research on a polarization-insensitive metamaterial absorber based on planar spiral structures

设计了一个基于平面螺旋结构的极化不敏感超材料吸波体。实验测试结果表明,在2.2 GHz处,超材料吸波体的反射率达到了-4.5dB。其总厚度为2.2mm,约为1/62个工作波长,面密度为0.88kg/m2。当金属基板的一条直角边与电场极化方向夹角分别为0,30,45,60和90°时,仍然具有同样低的反射率,超材料吸波体对垂直入射电磁波极化方向是不敏感的。与传统的吸波材料相比,该超材料吸波体实现了轻质、薄型化,且对入射电磁波极化方向不敏感。

Design of a polarization-insensitive metamaterial absorber based on spiral structures was presented.The measured results indicated that the metamaterial absorber demonstrates a reflectance of-4.5dB at2.2GHz.The thickness of the metamaterial absorber was 2.2 mm,about 1/62 of the working wavelength.The areal density was 0.88kg/m2.When the angle between the bottom side of the metal substrate and the field polarization direction were respectively 0,30,45,60 and 90°,the metamaterial absorber showed similar low reflectivity.This metamaterial absorber was lightweight,ultrathin and polarization-insensitive to the incident electromagnetic wave compared with traditional microwave absorbers.