本論文提出新式二維週期性合成傳輸線，使之具有準-TEM模態傳播，並可利用其電路單元結構之對稱方正特性，於系統有限空間中作任意之佈局。該二維週期性合成傳輸線係以簡易集總元件等效均勻傳輸線之特性，可實現大範圍之特徵阻抗與電氣長度，並以任意曲折繞線之方式使其具備高度電路微小化之能力。本論文將詳盡討論此合成傳輸線之設計原理、等效電路模型、以模擬與量測結果。
利用該合成傳輸線，本論文首先完成微型化枝幹耦合器、鼠競耦合器與威爾京森分波器；若與傳統設計相較，其電路縮小能力分別為80%、94%與83%，且同時具有與傳統設計相仿之良好電氣響應，本文並有表列以彰顯其電路特性與傳統設計之比較。
其次，本文利用二維合成傳輸線及多層板結構，實現微型化3-dB寬面方向耦合器。內文將探討奇偶模態之電路分析、模擬及量測結果，並提供奇偶模態之特徵阻抗及耦合量的設計圖表。此方向耦合器可經由調整二維合成傳輸線之電感及電容結構進行耦合量之控制。本文對耦合器之電路響應亦有深入探討與列表比較。與傳統設計相較，該寬面方向耦合器具有可觀縮短耦合長度之能力與良好的電氣響應。
最後，本論文成功利用二維合成傳輸線，設計微型化共模濾波器，其週期性之蕈狀結構係利用多層板實現。該創新設計可抑制共模雜訊低於15 dB，頻寬範圍為1.83 GHz ~ 3.68 GHz，且於頻寬範圍內亦具有良好之阻抗匹配。本論文亦提供完整之設計流程與表列比較，作為未來任意規格設計之依據。

A novel two-dimensional periodic synthesized transmission line, supporting quasi-TEM mode propagation, is proposed and investigated in this thesis. Benefitting from the square footprint and symmetrical structure of the proposed unit cell, the two-dimensional synthesized line exhibits extraordinary flexibility in layout arrangement within a limited space.
The proposed synthesized line is implemented by simple quasi-lumped elements, and is capable of providing a wide range of characteristic impedance and electrical length. The design concept, equivalent circuit model, and experimental results are carefully investigated and discussed.
By utilizing the proposed two-dimensional synthesized line, miniaturized branch-line coupler, rat-race coupler, and Wilkinson power divider are developed with not only a substantial miniaturization ratio but comparable circuit performances. The details of the proposed designs are tabulated and compared with the state-of-the-art designs in the literature.
A miniaturized 3-dB broadside coupled-line coupler is also realized on multilayer process using the two-dimensional synthesized line. Design graphs using even/-odd mode analysis are provided, which indicate that the coupling coefficient can be easily controlled by adjusting the lumped inductors and capacitors in the synthesized line. When compared with a conventional one, the proposed coupler features good performances and significant reduction in coupling length.
Finally, a miniaturized multilayer common-mode filter is also developed using the two-dimensional synthesized line along with the mushroom structure. It, outperforming the reported designs in terms of the occupied size, operates from 1.83 to 3.68 GHz with a common-mode rejection level of at least 15 dB.

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