ABSTRACT In this article, substrate integrated waveguide (SIW) filter with compact size and wide out-of-band rejection is designed for 5G (sub-6 GHz) applications. To achieve the proposed filter responses, D-shaped resonators oriented face-to-face are etched out on the top layer of SIW. Due to the resonators loading, the filter provides a passband below the cut-off frequency of SIW. This decrease in the operating frequency of the filter allows us to achieve size miniaturization. To enhance the frequency responses, a double-stage SIW filter is proposed and investigated. The equivalent electrical-circuits are developed to validate the transmission responses. To support our claim, single- and double-stage SIW filters are designed, fabricated and tested. The filter prototypes achieve size miniaturization, low insertion loss and wide out-of-band responses. The measured responses are very similar to the full-wave simulation responses.

中文翻译：

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使用 D 形谐振器的小型化 SIW 滤波器，具有适用于 5G 应用的宽带外抑制

摘要 在本文中，具有紧凑尺寸和宽带外抑制的衬底集成波导 (SIW) 滤波器专为 5G（低于 6 GHz）应用而设计。为了实现所提出的滤波器响应，在 SIW 的顶层蚀刻出面对面的 D 形谐振器。由于谐振器负载，滤波器提供低于 SIW 截止频率的通带。滤波器工作频率的这种降低使我们能够实现尺寸小型化。为了增强频率响应，提出并研究了双级 SIW 滤波器。开发等效电路以验证传输响应。为了支持我们的主张，我们设计、制造和测试了单级和双级 SIW 滤波器。滤波器原型实现尺寸小型化，低插入损耗和宽带外响应。测得的响应与全波模拟响应非常相似。