This letter presents a transition from a top layer grounded coplanar waveguide (GCPW) to an inner layer air-filled substrate-integrated waveguide (AFSIW). Such type of transition is crucial for the interconnection of top layer surface-mounted radio-frequency integrated circuits (RFICs), toward the integration of complete microwave and millimeter-wave systems taking advantage of the low-cost and high-performance AFSIW technological platform. To fulfill the new space application needs, the proposed transition has been developed in the satellite downlink Ka-band ranging from 27.5 to 31 GHz. The structure is detailed with design guidance. For experimental evaluation, a back-to-back prototype has been fabricated and measured. In the operating frequency range, the proposed transition achieves a simulated and measured insertion loss (IL) as low as 0.135 ± 0.015 dB and 0.3 ± 0.18 dB, respectively.

中文翻译：

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基板上高性能系统的多层 GCPW 到 AFSIW 过渡

这封信介绍了从顶层接地共面波导 (GCPW) 到内层充气基板集成波导 (AFSIW) 的过渡。这种类型的过渡对于顶层表面贴装射频集成电路 (RFIC) 的互连至关重要，从而利用低成本和高性能的 AFSIW 技术平台集成完整的微波和毫米波系统。为满足新的空间应用需求，已在 27.5 至 31 GHz 的卫星下行链路 Ka 频段开发了拟议的过渡。该结构在设计指导下进行了详细说明。为了进行实验评估，我们制作并测量了一个背靠背原型。在工作频率范围内，所提出的过渡实现了低至 0 的模拟和测量插入损耗 (IL)。