在飞行器隐身的研究中,如何有效地降低其表面雷达散射截面(RCS)是重点和研究热点.提出结构性吸收概念,利用如光带隙电磁结晶结构、高阻抗结构等周期性结构的带隙特性和阻抗特性,在物体表面设置单层或多层周期性结构,并通过在类似高阻抗表面的周期性金属单元表面铺设有源器件-变容二极管控制周期性结构的性能,从而实现对入射电磁波的吸收和对表面波的抑制,有效降低了机身表面的RCS.仿真实验证明采用单层或双层有源周期性结构表面,在周期性结构带隙频带内,可以将RCS减缩到3~14dB,并在多层结构理想化优化条件下,达到缩减RCS 20dB以上,并且可以通过电控方法控制减缩RCS的频带范围.
How to reduce Radar Cross Section(RCS) of aircraft's surface effectively is important and key issue at the field of research of aircraft steal.Structural absorb is proposed in this paper,using the periodical surface's character of band gap and impedance transition of electromagnetic crystal structure such as Photonic band gap and high impedance surface(HIS) and so on,to put single or multilayer periodical structure on the surface of the shell of aircraft,and to put the Varactor Diode onto the approximate HIS to join each cell of metal on top layer to realize the electronic control for periodical structure,will establish the active periodical structure.This structure could realize absorbing the exotic electromagnetic wave and restrain surface wave on it.The result of above process is reducing the RCS of the surface of aircraft effectively.The simulation test prove that this method and technology could reduce RCS 3~14 dB at working frequency band by using single or double layer active periodical structure,and reduce RCS 20 dB with the ideal condition of multilayer structure,and the working frequency band could be changed and controlled by electronic method also.