In this Letter, a compact and high-performance ultra-wideband (UWB) bandpass filter based on half-mode substrate integrated waveguide (HMSIW) is proposed. A novel slow-wave structure with lowpass characteristics is developed and loaded on the HMSIW to obtain the UWB frequency response and realise size-reduction. Moreover, two rectangular slots are etched on the transition structures of the microstrip-to-HMSIW to obtain a good UWB impedance matching. As a verification, a prototype is designed, simulated, fabricated and measured. Good agreements can be observed between simulated and measured performances.

中文翻译：

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基于 HMSIW 的紧凑型高性能 UWB 带通滤波器

在这封信中，提出了一种基于半模衬底集成波导 (HMSIW) 的紧凑型高性能超宽带 (UWB) 带通滤波器。开发了一种具有低通特性的新型慢波结构并将其加载到 HMSIW 上，以获得 UWB 频率响应并实现尺寸减小。此外，在微带到HMSIW的过渡结构上蚀刻了两个矩形槽以获得良好的UWB阻抗匹配。作为验证，原型被设计、模拟、制造和测量。在模拟性能和测量性能之间可以观察到良好的一致性。