论文部分内容阅读
微型频率选择表面(MEFSS)基于感性表面(金属栅格)与容性表面(间隔的金属环形贴片)之间的耦合机制实现带通滤波功能。采用全波分析矢量模匹配法精确计算了耦合介质的相对介电常数εr、厚度d对MEFSS传输特性的影响:εr由3.5变为2时中心频点高漂2.8GHz,d增加0.4mm时中心频点往低频漂移1.4GHz且透过率降低2.6dB。由此可见,通过控制耦合介质厚度能够实现MEFSS通带开关的功能:当耦合介质厚度增加1mm时通带中心频点透过率降低8.173dB。在覆铜的聚酰亚胺膜上复制光刻制备感性表面、容性表面并分别置于0.2mm、1.2mm厚泡沫板两侧采用自由空间法测试了其传输特性。计算与实验结果均表明:通过控制耦合介质厚度变化能够实现MEFSS通带开关的功能,为实现有源FSS提供一种新的方向。
The MEFSS band-pass filtering is based on the coupling mechanism between the inductive surface (metal grid) and the capacitive surface (spaced metal ring patches). The full-wave analysis vector mode matching method is used to accurately calculate the influence of the relative permittivity εr and the thickness d of the coupling medium on the transmission characteristics of MEFSS: when εr changes from 3.5 to 2, the center frequency is 2.8GHz high and the center of d is 0.4mm The frequency shifts to 1.4GHz and lowers the transmittance by 2.6dB. Thus, the MEFSS passband switching function can be realized by controlling the thickness of the coupling medium: when the coupling medium thickness increases by 1mm, the transmittance of the passband center frequency point decreases by 8.173dB. The transfer properties were measured by free-space method on the copper-clad polyimide film prepared by photolithography to prepare the inductive surface, the capacitive surface and placed on both sides of a 0.2mm, 1.2mm thick foam board respectively. The calculation and experimental results show that the function of MEFSS passband switch can be realized by controlling the variation of the coupling medium thickness, which provides a new direction for the realization of active FSS.