本論文是針對文獻中缺乏完整合成理論之特殊耦合線濾波器，推導出其等效電路，進而從原型電路架構出發，利用符合此等效電路之橢圓及廣義柴比雪夫合成理論，設計符合需求規格之濾波器響應。本研究不同於傳統只計算傳輸零點的方式，它能控制通帶響應情況，由於知曉原型電路及其物理特性，因此能進階設計高階的濾波器，以及提出抑制多餘通帶的方法，分別為抑制直流通帶及第一諧波通帶兩類，藉此增加濾波器之實用性，而在縮減電路面積方面則是運用非對稱或三線耦合結構來取代。本論文並將近幾年其他文獻中之寬頻帶拒濾波器，與本論文討論的Y型耦合線帶拒濾波器與髮夾型帶拒濾波器進行比較，最後以電磁模擬及實作來驗證這些架構與合成理論之正確與實用性。
傳統雙耦合線之等效電路架構，其非輸入輸出埠端通常為開路或是短路情形，但文獻中卻鮮少討論彼此連接之情況，本研究詳加探討這些狀況之等效電路，並比較它們與一般開、短路情況等效電路之差異，將這些電路整理為圖表，當作未來研究的參考。

In recent years, many new coupled-line filters structures have been proposed. However, the complete synthesis procedures and design equations are not well developed. In this thesis, coupled transmission-line models are used to derive the filters' equivalent circuits. They are then synthesized to realize Elliptic and Generalized Chebyshev functions. Therefore, the filters passband response could be well controlled by designers. Therefore, exact synthesis is more effective than only controlling transmission zero positions. Also higher order filters are proposed because equivalent circuits show the possibility. This thesis then discusses the methods for suppression of DC and first spurious passband. Asymmetric and three coupled-line structure are used for size reduction. Finally, the proposed designs are verified by using EM simulations and experiments.
The terminals of two-coupled lines are usually open- or short-circuited except at the input and output ports. These circuits had been well studied. On the other hand, coupled-line sections with extra connection between terminals are seldom discussed in the literatures. In this study, these circuits have been studied. They are compared to other open-and short-circuited coupled line sections. The equivalent circuits are derived for references.

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