In this article, a novel structure is proposed for the realization of cavity section in the printed gap waveguide (PGW) technology. For the proof of the concept, a multilayer cavity-backed slot antenna element is designed and fabricated so that its performance can be compared to the devices in the literature made by printed circuit board (PCB) technology and also by metal parts using the CNC machine. The proposed structure benefits from the advantages of efficient, low cost, simplified fabrication process, lightweight, and high aperture efficiency compared to common cavity-backed antennas. To manage the available space, the feed is connected to the antenna cavity from the underneath using a coupling aperture. The proposed configuration simplifies the integration of accessory devices in antenna arrays, such as feed networks, phase shifters, and amplifiers. Also, the separation of feed network from the radiation slot section prevents any unwanted radiation. Using the mode analysis, four slots were implemented in the proposed cavity to achieve four equivalent magnetic surface currents with identical phase and magnitude. The antenna operating frequency is 16 GHz, the realized antenna radiation and aperture efficiencies are over 92% and 81.6%, respectively, and its achieved gain is 12 dBi.

中文翻译：

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高效的 2×2 印刷电路带隙背腔缝隙天线

在本文中，提出了一种新颖的结构来实现印刷间隙波导 (PGW) 技术中的腔体部分。为了证明这一概念，我们设计并制造了一个多层背腔缝隙天线元件，使其性能可以与文献中使用印刷电路板 (PCB) 技术以及使用 CNC 机器制造的金属部件制造的设备进行比较. 与普通背腔天线相比，所提出的结构受益于高效、低成本、简化的制造工艺、重量轻和高孔径效率的优点。为了管理可用空间，馈源使用耦合孔径从下方连接到天线腔。建议的配置简化了天线阵列中附件设备的集成，例如馈电网络、移相器、和放大器。此外，馈电网络与辐射槽部分的分离可防止任何不需要的辐射。使用模式分析，在建议的腔体中实现了四个槽，以实现具有相同相位和幅度的四个等效磁表面电流。天线工作频率为16 GHz，实现的天线辐射效率和孔径效率分别超过92%和81.6%，实现的增益为12 dBi。