In this letter, a wideband coaxial to air-filled waveguide transition is proposed, which has been realized by the substrate integrated waveguide (SIW) technology. The present design incorporates several air-filled vias of varying hole diameter to efficiently match the impedance over a wide operating bandwidth in the dominant TE10 mode, hence replacing the need for dielectric taper or larger footprint. A transition prototype has been designed and tested to validate the results. The measured return loss is better than 15 dB and insertion loss of 1 ± 0.1 dB over the band of interest (9.5–15 GHz), hence portraying a near-octave bandwidth from the proposed design.

中文翻译：

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具有近倍频程带宽的同轴到充气基板集成波导过渡

在这封信中，提出了一种宽带同轴到充气波导的过渡，该过渡已通过衬底集成波导 (SIW) 技术实现。本设计结合了几个不同孔径的充气过孔，以在主要的 TE10 模式下有效匹配宽工作带宽内的阻抗，从而取代了对介质锥度或更大尺寸的需求。已经设计并测试了过渡原型以验证结果。测得的回波损耗优于 15 dB，在感兴趣的频带（9.5-15 GHz）上的插入损耗为 1 ± 0.1 dB，因此描绘了所提议设计的近倍频程带宽。