Gap waveguide (GW) technology, taking advantage of contactless electromagnetic band-gap (EBG) structures, solves the contact issue of conventional rectangular waveguides and provides a reliable method for packaging with planar circuits. Herein, a slow wave GW (SW-GW) structure with bandpass filtering functionality is presented. Utilizing the low-frequency cutoff characteristic of the GW and band-stop effect of the quasi-periodic transverse corrugations inside the GW, the lower and upper stopbands of the SW-GW can be easily achieved and reconfigured for different bandwidth requirements. The relationship between the dispersion diagram and the filtering characteristics, including the pass and stop bandwidths and group delay (GD), is studied to provide a simple but effective design guideline. The presented SW-GW reduces the design and implementation difficulties of conventional filters, especially wideband filters. A prototype operating at 24–30 GHz is designed and manufactured to validate the idea, and a good agreement is achieved between the measurement and simulation results.

中文翻译：

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具有带通滤波功能的慢波隙波导

间隙波导（GW）技术利用非接触式电磁带隙（EBG）结构，解决了传统矩形波导的接触问题，为平面电路封装提供了可靠的方法。本文提出了一种具有带通滤波功能的慢波 GW (SW-GW) 结构。利用GW的低频截止特性和GW内部的准周期横向波纹的带阻效应，SW-GW的上下阻带可以很容易地实现和重新配置以满足不同的带宽要求。研究了色散图和滤波特性之间的关系，包括通过和停止带宽以及群延迟 (GD)，以提供简单但有效的设计指南。所提出的 SW-GW 降低了传统滤波器，尤其是宽带滤波器的设计和实现难度。设计和制造了一个工作在 24-30 GHz 的原型来验证这个想法，并且在测量和仿真结果之间取得了很好的一致性。