在本論文中，對窗片(windows)依照所需求的頻帶進行模擬跟分析計算。並且在分析計算的過程中，加入模式分析(Modal analysis)來處理因為半徑不連續而被激發出來的其他模式。一開始先以Maxwell’s equation先求出圓形波導管的一組正交的本徵解，再計算於半徑不連續的地方，利用模式的正交特性求出其他被激發的模式的振幅。再經由線性代數的概念延伸到多個不連續半徑的狀況，好用來對windows進行計算。並且與在不考慮模式效應下，以阻抗匹配的概念所計算的結果進行比較，以及探討在不同的狀況下，反射相對應於頻率的改變。在結果上，由於我們是採取週期性的結構，所以我們隨著頻率是有週期性的變化，產生在高頻段的部分仍有通帶的存在。

In this paper, we get the windows by simulation with calculation. We used the Maxwell’s equation to get the eigenmodes. And modal analysis is applied to calculate the amplitudes of those excited waveguide modes in radius discontinuity problem. We will get the amplitude of other modes by orthogonalities of waveguide eigenmodes. We extend the result to multi-discontinuity case by use linear algebra technique. We used to analyze windows and periodic structure. And compare the results of the calculation to the concept of impedance matching of mode effect are not considered, and investigates the result of different situations. On the results, we take periodic structure, so we are cyclical changes with frequency. We can get some pass bands in high frequency.

摘要.................................................... i
Abstract............................................... ii
致謝................................................... iii
第一章 緒論.............................................. 1
1.1 window簡介.......................................... 1
1.2 論文概述............................................. 3
第二章 理論推導........................................... 4
2.1波導管基本模式推導......................................4
2.1.1 波導管的特徵模式.....................................4
2.1.2 圓柱形波導管的推導................................... 7
2.2單一個半徑不連續的模式分析................................9
2.3多重的半徑不連續邊界的模式分析.................... ........15
2.3.1左右皆有入射.........................................15
2.3.2 雙邊界問題..........................................17
2.3.3 多重邊界問題........................................21
2.4微波電路的概念..........................................24
第三章 應用例子與計算結果....................................25
3.0 Window..............................................25
3.1Window - 簡介.........................................25
3.1-1 Window – 採用此結構的原因............................26
3.2Window – Mathematica模擬結果...........................27
3.3Window – 單片窗和三片窗的比較............................29
3.4Window – 考慮加工會產生的問題............................31
3.4-1 Window – 相對電容率的變化............................31
3.4-2 Window – 長度上的變化................................32
3.5 Window – 收斂度測試...................................34
3.6Window – 計算結果比較...................................37
第四章 結論...............................................39
附錄A....................................................41
附錄B....................................................44
附錄C....................................................48
參考文獻..................................................55

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