介质层中频率选择表面散射特性分析

利用等效电路法分析了一种夹于介质层中的频率选择表面的散射特性。这种频率选择表面是由具有低通高阻选频特性的栅格方回路振子阵列构成。数值计算结果表明,介质夹层频率选择表面结构具有较好的反射和透射谐振频率可调性,并且其频率响应特性随入射波入射角的变化较缓慢。利用这种结构,可以制作低雷达散射截面天线的滤波反射面。

ANALYSIS OF FSS SANDWICHED IN A DIELECTRIC SHEET

The equivalent-circuit model (ECM)has been used to analyze the transmission performance of the frequency-selective surfaces(FSS).If the FSS is electrically free-standing or printed on an electrically thin dielectric substrate,the ECM approach is very efficient and accurate,However,in many actual applications, especially in aero space applications,the FSS is usually inserted in or etched on a thick dielectric sheet.To account for the influence of the di-electric material on the FSS’s frequency response,the simple ECM and a transmission line the-ory are used fo predict the fransmission and reflection characteristics of the FSS, which is com-prised of gridded-square arrays sandwiched in a dielectric sheet illuminated by a plane wave at arbitrary incident angle. It is found from the numerical results that the sandwiched FSS has good frequency-selective performance and insensitive incident angle response.This sandwiched FSScan be used as the refleclor of a small radar cross section(RCS)antenna system.