In this paper, equivalent circuit models are first presented for characterizing the CPW SSPPs with etched slot. The asymptotic frequency and dispersion are investigated based on the theoretical model. And the analyses reveal that both the asymptotic frequency and dispersion curve can be manipulated by changing the inductance brought by the etched slots and the capacitance of the loaded capacitors. To validate the propagation performance, the proposed SSPP structure was fabricated and tested. The experimental results are consistent with the theoretical analysis, indicating that the designed SSPP structure possesses excellent low-pass filtering characteristics. Compared with traditional SSPP structures, the proposed structure exhibits a much narrower transversal width and does not require mode-conversion structures.
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