基于方环结构的柔性透明宽角散射编码超表面设计

Design of Flexible Transparent Wide Angle Scattering Coded Metasurface Based on Square Ring Structure

设计了一种基于氧化铟锡(ITO)电阻膜的2-bit柔性透明编码超表面。该结构采用电磁层-介质层-反射层的三层设计,选用ITO粉末喷涂在柔性透明的聚对苯二甲酸乙二醇酯(PET)上作为电磁层,通过激光雕刻技术将ITO层加工成不同尺寸的方环结构,选用柔性透明的聚氯乙烯(PVC)作为介质基板、金属钢板模拟理想导体(PEC)作为反射层,探究该超表面在金属装备表面的电磁衰减特性,样品测试结果显示在450~740 nm波长范围内超表面的透光率达到50%。通过对10~18 GHz电磁频段内的反射相位研究,得到2-bit编码基本单元,利用棋盘排布和随机算法编码优化两种排列方式进行编码,实现Ku波段衰减10 dB的目标。当入射角发生改变时,该结构能在较宽角度下保持良好的衰减效果,在15 GHz频率斜入射时,编码超表面在小于60°范围内双站雷达散射截面(RCS)衰减仍可达到10 dB。

A 2-bit flexible transparent coded metasurface based on indium tin oxide(ITO)resistance film was designed.A three-layer design of electromagnetic layer,dielectric layer and reflection layer was adopted for the structure.ITO powder was sprayed on the flexible and transparent polyethylene terephthalate(PET)as the electromagnetic layer.The ITO layer was processed into square ring structure with different sizes by laser engraving technology.The flexible and transparent polyvinyl chloride(PVC)was selected as the dielectric substrate,and the steel plate as a simulated perfect electrical conductor(PEC)was selected as the reflector.The electromagnetic attenuation characteristics of the metasurface on the surface of the metal equipment were investigated.The sample test results show that the transmittance of the metasurface reaches 50%in the wavelength range of 450-740 nm.By studying the reflection phase in the electromagnetic frequency range of 10-18 GHz,the 2-bit coding basic unit was obtained.The checkerboard arrangement and random algorithm coding optimization were used to encode.The goal of Ku-band attenuation of 10 dB was achieved.When an incident angle changes,the structure can maintain a good attenuation effect at a wide angle.At an oblique incidence frequency of 15 GHz,the two-station radar cross section(RCS)attenuation of the coded metasurface can still reach 10 dB in the range of less than 60°.