在這篇論文裡描述了如何增加空腔耦合之寬頻微帶線垂直轉接之頻寬的方法。經由改變耦合槽孔結構以及微帶線残段結構，可以使得比例頻寬增加大約30%左右。其優點除了提供更多的頻寬之外，比起一般傳統中具有共同特徵所使用矩形槽孔耦合與四分之ㄧ波長微帶線残段的結構，這種改變耦合槽孔與微帶線残段的設計方法所能得到的好處就是，可以減少耦合槽孔與微帶線残段在縱向尺寸的長度。這樣的特性對於一個需要高元件密度之微波電路而言將頗有助益。有限元素分析法將用來執行本論文內所需要的數值模擬，主要是基於這種數值方法在立體結構上的精確度。此外，亦會探討使用矩形空腔耦合以及圓柱空腔耦合的垂直轉接。這些模擬結果均將以實驗量測的方法來應證其正確與否。在這裡所描述的設計將會呈現出較為寬頻與低介入損失的垂直轉接。

Techniques to increase the bandwidth of broad-band cavity-coupled microstrip vertical transitions are described in this thesis. By varying the configurations of coupling slots and tuning stubs of the vertical transitions, a more than 30% increase in bandwidth can be achieved. Besides the advantage of offering more bandwidth, another common feature of these designs is the size reduction in the longitudinal direction of the coupling slots and the tuning stubs in comparison with the rectangular coupling slots and the quarter-wavelength microstrip tuning stubs employed by the conventional designs. This characteristic is critical for modern microwave circuit designs requiring high density in circuit elements. The finite-element method was chosen to perform the required simulations for the proposed designs because of its accuracy for the structures described in this thesis. Both rectangular and circular cavity-coupled vertical transitions are under investigation. The validity of the simulation results has been assessed by measured data obtained from experiments. It demonstrates that the designs presented here can provide vary wide-band and low-insertion-loss vertical transitions.

誌謝 i
中文摘要 ii
英文摘要 iii
目錄 iv
圖目錄 vi
表目錄 ix
第一章 緒論 1
1.1 動機與目標 1
1.2 章節概要 3

第二章 空腔耦合架構與分析 5
2.1 結構與設計 5
2.2 選擇數值計算法 9
2.3 頻譜解析 11
2.4 量測與校正 14
2.5 影響空腔耦合的參數 18

第三章 現有空腔結構設計 21
3.1 矩形空腔 21
3.2 圓柱空腔 27
3.3 最佳空腔的選擇 31

第四章 增加頻寬的槽孔設計 33
4.1 蝶形領結槽孔 33
4.1.1 矩形空腔、蝶形領結槽孔的設計 34
4.1.2 圓形空腔、蝶形領結槽孔的設計 38
4.2 扭曲H形槽孔 40
4.2.1 矩形空腔、H形槽孔的設計 41
4.2.2 圓形空腔、H形槽孔的設計 43
4.3 交錯矩形槽孔 45
4.4 最佳槽孔的選擇 47

第五章 設計微帶線殘段增加頻寬 50
5.1 步階狀殘段 50
5.2 放射狀殘段 54
5.3 最佳殘段的選擇 57

第六章 結論 60

參考文獻 63

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