In this paper, a novel directional filter (DF) is proposed and implemented using substrate integrated waveguide (SIW) technology which exhibits the advantages of compact size and simple structure. The proposed DF is realized by two half mode substrate integrated waveguides (HMSIWs) and two substrate integrated circular cavity (SICC) resonators operating in the TM110 degenerate modes in which an aperture is utilized to realize the coupling between HMSIWs and SICCs. Two slotlines with appropriate dimensions, etched on the top and bottom planes, are utilized in order to control coupling strength between two cascaded SICC resonators. The proposed two-circular cavity SIW DF at 12.3 GHz is designed and fabricated with a normal printed circuit board process. Measured and simulated results indicate that the DF has a 3.25% bandwidth, and the return loss as well as isolation are better than 10.5 and 15 dB, respectively.

中文翻译：

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使用基板集成圆形腔的紧凑型 SIW 定向滤波器

在本文中，提出并使用衬底集成波导（SIW）技术实现了一种新型定向滤波器（DF），该滤波器具有尺寸紧凑和结构简单的优点。所提出的 DF 由两个半模基板集成波导 (HMSIW) 和两个在 TM 中运行的基板集成圆形腔 (SICC) 谐振器实现110利用孔径实现HMSIW和SICC耦合的简并模式。为了控制两个级联 SICC 谐振器之间的耦合强度，利用蚀刻在顶部和底部平面上的两条具有适当尺寸的槽线。所提出的 12.3 GHz 的双圆腔 SIW DF 采用普通印刷电路板工艺设计和制造。测量和仿真结果表明，DF 具有 3.25% 的带宽，回波损耗和隔离度分别优于 10.5 和 15 dB。