This letter presents a filtering substrate integrated waveguide slot antenna design with multiple radiation nulls based on a double slot coupling scheme. It consists of a dual-layer cavity resonator, a slot in the first layer, and two coupling slots inserted in the middle layer. The slot in the first layer functions as the antenna radiator. This radiator is etched in the first cavity instead of the last stage of the network, resulting in two radiation nulls. A double slot coupling scheme is employed in the middle layer to not only couple the two-layer cavity resonators but also generate two more radiation nulls. Owing to these radiation nulls, the antenna features high-frequency selectivity as well as out-of-band radiation suppression level. For demonstration, the proposed filtering antenna is implemented and tested. The antenna operates at the center frequency 4.5 GHz with 15.4% (4.2-4.9 GHz) measured bandwidth. The maximum gain within the operating band is 7.5 dBi and four radiation nulls are generated. Better than 21 dB out-of-band radiation rejection level is obtained.

中文翻译：

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采用双槽耦合方案的双层滤波 SIW 槽天线


这封信提出了一种基于双缝隙耦合方案的具有多个辐射零点的滤波基板集成波导缝隙天线设计。它由双层空腔谐振器、第一层的槽和插入中间层的两个耦合槽组成。第一层中的槽用作天线辐射器。该辐射器被蚀刻在第一个腔体中，而不是网络的最后一级，从而产生两个辐射零点。中间层采用双槽耦合方案，不仅耦合两层空腔谐振器，而且还产生两个以上的辐射零点。由于这些辐射零点，天线具有高频选择性以及带外辐射抑制水平。为了进行演示，实施并测试了所提出的滤波天线。该天线的工作中心频率为 4.5 GHz，测量带宽为 15.4% (4.2-4.9 GHz)。工作频段内的最大增益为 7.5 dBi，并生成四个辐射零点。获得优于 21 dB 的带外辐射抑制水平。