In this paper, a triple-band bandpass filter using a multi-mode half-mode substrate integrated waveguide (HMSIW) cavity is presented. In this design, back-to-back connected half-mode defected ground structure (DGS) is loaded into the HMSIW cavity, which generates the first passband. The first four modes of HMSIW cavity are TM110, TM120, TM310, and TM320. They have been used to generate second and third passbands. The slot line perturbation is used to shift the modes close to each other. Here, TM110 and TM120 constitute second passband, and TM310 and TM320 give third passband. Moreover, the notch band is designed using embedded open-circuited stub to improve the attenuation between the second and third passbands. The proposed filter is designed and fabricated on RT/Duroid 5880 substrate with a thickness of 0.508 mm. The measured results are in line with simulated ones for each of the passbands, and the center frequencies are 6.28, 13, and 19.12 GHz.

中文翻译：

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使用多模 HMSIW 腔和半模 DGS 的紧凑型三频带带通滤波器

在本文中，提出了一种使用多模半模基板集成波导 (HMSIW) 腔的三波段带通滤波器。在此设计中，背靠背连接的半模缺陷接地结构 (DGS) 被加载到 HMSIW 腔中，从而产生第一个通带。HMSIW腔的前四种模式是TM值110,TM值120,TM值310， 和TM值320. 它们已被用于生成第二和第三通带。槽线扰动用于移动模式彼此接近。这里，TM值110和TM值120构成第二通带，并且TM值310和TM值320给第三个通带。此外，陷波带采用嵌入式开路短截线设计，以改善第二通带和第三通带之间的衰减。所提出的过滤器是在厚度为 0.508 mm 的 RT/Duroid 5880 基板上设计和制造的。测量结果与每个通带的模拟结果一致，中心频率分别为 6.28、13 和 19.12 GHz。