本論文的研究在於雙頻帶環型濾波器設計的探討，其中包含混附波可調、低損失以及微小化三個觀點。本論文首先研究雙模態以及步階式阻抗共振器。我們分析了雙模態以及步階式阻抗共振器的理論，並計算以及設計雙頻帶上的應用。我們發現適當設計步階式阻抗共振器於環型結構內，可以適當調整混附波響應的頻率位置。然而，在保持通帶的特性為前提下，常用的步階式阻抗共振器並無法有效控制混附波的位置，使其成為第二個通帶。因此，我們提出一種新型的步階式阻抗共振器結構。利用該新型的步階式阻抗共振器結構，除了可以保持雙模態濾波器的特性外，亦可良好控制混附波的位置，成為雙頻帶環型濾波器。
其次，我們從低損失以及微小化的觀點，探討新型的步階式阻抗共振器結構參數，將濾波器特性更進一步改善。在低損失的目標下，我們可以利用共平面波導饋入來改善傳輸損失。在微小化的目標下，我們結合高介電常數微波陶瓷基板，大幅降低濾波器的尺寸。另一方面，我們亦結合低溫共燒陶瓷製程，使其更貼近產業量產的需求。我們詳細地分析與比較所提出的各式濾波器的特性，並且藉由數個濾波器的製作驗證了本論文所闡述的設計方法的正確性。
最後，本論文將雙模態濾波器使用基板整合波導結構，設計K頻帶用之濾波器，其具有低損失以及高選擇性的特性。我們完整地探討不同架構的雙頻帶環型濾波器，包含微帶線餽入以及共平面波導饋入。此外，我們亦提出不同的製程技術來結合，並具體實現。在微波電路設計中，環型共振器扮演了重要的角色，因為它具有無終端效應以及結構簡單的特性。在未來越來越高的操作頻率下，將更被廣為設計。此外，封裝貫孔所引起之電感效應以及寬頻介質共振天線在本論文也被研究與驗證。

This research is about the improved ring resonator filter designs including three aspects of the adjustable spurious, low-loss and miniaturization. This thesis starts from the fundamental studies of dual-mode and stepped-impedance-resonator (SIR) is introduced. The theory of the dual-mode and SIR are analyzed that can be used for calculating and designing the dual-band application. It can found that design the SIR in the ring resonator structure, the position of spurious response can be adjusted properly. However, the conventional SIR can't control the position of spurious response, and keep the passband characteristic, simultaneously. Therefore, a novel SIR structure is proposed in this thesis. It introduces the proposed SIR structure that can keep the characteristic of the dual-mode filter. Besides, the position of spurious response can also be controlled accurately.
In the second part of this thesis, the viewpoint of low-loss and miniaturization are first reviewed. In the viewpoint of low-loss, the coplanar-waveguide (CPW) feeding in input and output (I/O) can be adopted and improved transmission loss. In the viewpoint of miniaturization, the filter combines the high dielectric constant (high- ) ceramic substrate that reduces the resonator size. On the other hand, the filter also combines low-temperature-cofired-ceramic (LTCC) that to enhance the ability of production in large quantity. The characteristics of the proposed filters are analyzed and compared, and all of them have been experimentally verified.
In the last part of this thesis, a K-band dual-mode filter using substrate integrated waveguide (SIW) structure with low-loss and high selectivity is designed. In this thesis, several structures of the filters are discussed, including microstrip and CPW feeding in I/O. In addition, several type of the filter are fabricated on the different substrate, and this concept has been successfully realized. In microwave circuits design, the ring resonator has played an important role. Because of the ring have the characteristic of no fringing field and simple structure. The ring resonator concept in microwave circuits design will more important in the millimeter-wave.

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