An FR4-based dc to 60 GHz transition from substrate integrated suspended line (SISL) to suspended coplanar waveguide (SCPW) is proposed in this letter. The design is fabricated using standard multilayer printed circuit boards (PCB) technology, and the substrates used are all low-cost FR4. Since the whole structure is in the suspended form, the bandwidth of the transition has been expanded three times when compared with the state of art. By using SISL with double-metal layer and patterned substrate, the loss of the transition is further reduced, and the conductor loss and dielectric loss have been individually analyzed. The results show that the proposed back-to-back transition has an insertion loss of less than 2.7 dB and a return loss of better than 11.4 dB from dc to 60 GHz.

中文翻译：

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基于 FR4 的 DC 至 60 GHz 衬底集成悬浮线到悬浮共面波导过渡

在这封信中提出了一种基于 FR4 的直流到 60 GHz 从衬底集成悬浮线 (SISL) 到悬浮共面波导 (SCPW) 的过渡。该设计采用标准多层印刷电路板 (PCB) 技术制造，所用基板均为低成本 FR4。由于整个结构为悬浮形式，与现有技术相比，过渡带宽扩大了三倍。通过使用具有双金属层和图案化衬底的SISL，进一步降低了过渡损耗，并分别分析了导体损耗和介电损耗。结果表明，所提出的背对背转换的插入损耗小于 2.7 dB，从直流到 60 GHz 的回波损耗优于 11.4 dB。