本論文主要係使用步階阻抗共振器研製雙頻帶微波部份網狀式及全網狀式帶通濾波器和雙頻帶平衡式及平衡至單端帶通濾波器。其電路設計概念、實現方式及量測模擬結果皆於本論文中詳細討論。
本論文首先探討步階阻抗共振器的原理，並依設計步驟，針對設計參數的決定、外部品質因數的萃取及共振器之間的耦合係數萃取，分別詳細探討，最終實現並量測之。在設計雙頻帶濾波器上，皆使用兩分開共振耦合路徑提升通帶之選擇性。網狀式濾波器的結構著重於電路縮小化的程度；平衡式濾波器則著重於實現雙頻帶通之效果。
由模擬及實驗結果可知，部份網狀式及全網狀式雙頻濾波器具有電路縮小化之效果。雖使用為數眾多之金屬貫孔，但其穿透損耗並未明顯增加。平衡式雙頻濾波器雖如預期具有雙頻帶效果，但反射係數、穿透係數及共模抑制效果欠佳，其原因及改善方式將在本論文中探討。

In this thesis, the stepped-impedance resonator (SIR) technique is mainly need to develop the partial net-type and full net-type dual-band microwave bandpass filters. Moreover, it is also applied to implement balanced and balanced-to-single-ended dual-band microwave bandpass filters. The detailed circuit design concept, implementation, and verification are presented in the thesis.
Firstly, the principles of the stepped-impedance resonator are described. Followed by the design procedures, determination of parameters, and extraction of external quality factor and coupling coefficient between the resonators, the filters are realized and measured. In design of the dual-band bandpass filters, two resonance coupling paths are employed to improve the sharpness of the passband. The net-type filters focus on the circuit miniaturization, while the balanced filters focus on realization of the dual passbands.
Based on the simulated and measured results of this thesis, partial net-type and full net-type dual-band filters can obtain the significant circuit size reduction. Although a number of vias are adopted in the circuit design, it does not lead to the increase of the insertion loss. The developed balanced filters successfully achieve two specified passband. However, the reflection coefficient, transmission coefficient, and common -mode suppression are not as good as expected. The reasons and the improvement methods will be discussed in the thesis.

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