In this work, an enhanced 3D frequency selective surface (FSS) patch antenna is proposed for 5G applications. A 23 to 26 GHz patch antenna was first designed before improving its performance by adding a 3 × 5 unit cell two-layer 2D transmission FSS structure. Then, reflective walls were placed on the side edges of the obtained structure in order to focus the incident field towards the main lobe; the aim being to build a 3D FSS structure without requiring the 3D printing technique. The total size of the obtained antenna is of 40 × 40 × 14 mm³. A comparative study was carried out between the performances of the patch antenna, the 2D FSS antenna and the 3D FSS antenna. A good agreement was observed between simulated results and measurements. An improvement of almost 3 and 2 dBi was obtained compared to the 2D FSS case, respectively, in simulated and measured results, while the side lobes in radiation patterns were decreased by more than 4 dBi, which confirms the adequate proposed design in switching to 3D structures.

中文翻译：

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通过使用 3D FSS 结构增强 5G 天线性能

在这项工作中，提出了一种用于 5G 应用的增强型 3D 频率选择表面 (FSS) 贴片天线。首先设计了 23 至 26 GHz 贴片天线，然后通过添加 3 × 5 单位单元两层 2D 传输 FSS 结构来提高其性能。然后，将反射墙放置在所获得结构的侧边缘，以便将入射场聚焦到主瓣；目的是在不需要 3D 打印技术的情况下构建 3D FSS 结构。所得天线的总尺寸为 40 × 40 × 14 mm ³. 对贴片天线、2D FSS天线和3D FSS天线的性能进行了比较研究。在模拟结果和测量之间观察到良好的一致性。在模拟和测量结果中，与 2D FSS 情况相比，分别获得了近 3 和 2 dBi 的改进，而辐射方向图中的旁瓣降低了 4 dBi 以上，这证实了在切换到 3D 时提出的适当设计结构。