A simple structured single layered frequency selective surface (FSS) that has unit cell size of 11 × 11 mm², substrate thickness of 0.8 mm only and capable to work in a very widespread band from 0.001 to more than 17 GHz is proposed in this article. The FSS is competent to augment the gain of a UWB monopole antenna by 2 to 3.5 dBi when integrated at the back of antenna. The performances of “antenna‐FSS” structure is evaluated by simulation and experimental measurement where good correlations are obtained. The integrated structure provides wide impedance band (S₁₁ < −10 dB) from 2.82 to 19.94 GHz (more than 150%) with improved broadside radiation and high radiation efficiency profile. The transient and frequency domain characteristics of “antenna‐FSS” composite structure are also evaluated in close proximity of diverse sub‐surfaces such as dry sand, wet sand, wood and concrete where an almost unaltered impedance band profile, linear transfer function response and non‐varying group delay responses are achieved which establishes the applicability of the composite structure in ground penetrating radar for low depth sub‐surface scanning applications.

中文翻译：

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紧凑的单平面超宽带频率选择表面，用于改善天线增益和探地雷达应用

本文提出了一种简单的结构化单层频率选择表面（FSS），它的晶胞尺寸为11×11 mm ²，基板厚度仅为0.8 mm，并且能够在0.001至17 GHz以上的非常宽的频带内工作。当集成在天线背面时，FSS可以将UWB单极天线的增益提高2至3.5 dBi。通过仿真和实验测量来评估“天线-FSS”结构的性能，可以获得良好的相关性。集成结构可提供宽阻抗带（S ₁₁ 在2.82至19.94 GHz（小于150％）时<-10 dB），且宽边辐射得到改善，辐射效率曲线高。还评估了“天线-FSS”复合结构的瞬态和频域特性，这些特性在接近干燥的沙子，湿的沙子，木材和混凝土等不同的次表面附近进行了评估，这些地方几乎没有改变，阻抗带分布，线性传递函数响应和非可以实现不同的群时延响应，从而确定了复合结构在低深度地下扫描应用中的探地雷达中的适用性。