改变Y孔单元排列方式对FSS极化稳定性的影响

以Y孔为基本图形单元,通过改变传统的单元排列方式,设计了一种极化稳定的频率选择表面(FSS)。利用模式匹配法进行了理论分析,得出频率与传输系数曲线。采用镀膜和光刻技术分别制备了Y孔单元传统和改进排列方式的FSS实验样件,在微波暗室中,对不同极化方式的电磁波在30°入射时进行测试,得到的实验曲线与理论仿真曲线基本一致。数值分析和实验结果均表明:当入射波的极化方式改变时,传统排列方式的FSS频率响应特性会发生明显改变,中心频率处的传输损耗增加-1.09 dB;但改进排列方式的FSS仅增大-0.25 dB。改进的FSS结构能在单一频率下产生谐振并具有很好的极化稳定性,为入射波源极化方式未知情况下的应用提供了设计思路。

Influence on polarization independence of frequency selective surface by altering Y slot element arrangement

A novel polarization-independent Frequency Selective Surface(FSS) is designed by altering traditional Y slot element arrangement. Based on the modal matching method, the frequency response of this structure is analyzed to obtain the plot of frequency versus transmission coefficient. With coating technology and lithography, the FSS samples of conventional and improved arrangement are made respectively. The tests under different polarized waves at 30° incidence angle are given in the microwave darkroom. The measured curve shows good agreement with the simulated curve. Both of the numerical analysis and experiment results show that the response of FSS with the conventional arrangement is changed very distinctly with the source polarization, the increase of transmission loss is -1.09 dB; but with the modified structure, the increase is only -0.25 dB. The improved Y element array can be resonant at a single frequency and has good polarization independency. It provides a new design method for that the polarization situation of a source is completely unpredictable.