臺灣博碩士論文加值系統

把很複雜的共振腔問題當成近似傳輸線來看，而得到簡化的解析公式，就是所謂ETL(Equivalent Transmission Line)方法。ㄧ般標準機殼尺寸之主模態頻率約為數百MHz，對於CPU動輒數GHz的頻率，比主模態更高階的模態是需要考慮的。多數論文中，只討論單一槽孔問題，不符合實際上機殻的陣列槽孔排列，故本文提出了適用陣列槽孔的ETL方法及高階模態修方法。由於通常陣列槽孔不會在金屬板的中間，故又提出了可修正位置偏移量的ETL方法。
基於工業設計及美觀的考量，本文就各種可能的槽孔排列形狀，就如何適用ETL的處理方法做出討論，最後再提出如何提高遮蔽率的方法。
利用屬於全波模擬的FDTD(Finite-Difference Time Domain)方法去模擬共振腔的結構是沒效率的。傳統ETL方法雖比全波模擬快，但卻有位準不精確及不能得到高階模態的缺點，本文將提出改善方法，期望能達成準確及縮短計算時間的目的。

Using analytical formula to estimate a complex problem of cavity based on a transmission line approach is called the ETL (Equivalent Transmission Line) method .
Operating frequency of dominant mode of standard case is several hundreds of megahertz that is lower than frequency of CPU, higher-order mode must be considered . Several papers always discuss a single aperture that does not correspond to practical array of apertures of case .Array of apertures can be estimated using analytical formula and higher-order mode can be considered in this paper .Usually array of apertures is not placed at the center of metallic plate, we can modify the analytical formula to get ETL of shifted array of apertures.
To consider industrial design and esthetics, many possible shape of array of apertures are discussed by adapting to the ETL method .The problem of how to improve the shielding effectiveness of array of apertures is treated in the latter half of this thesis.
The FDTD (Finite-Difference Time Domain) method is a full-wave analytical algorithm and is not efficient for analyzing cavity. Advantage of ETL is that it is faster than full-wave analytical algorithm .However, traditional ETL can not get accurate level of shielding effectiveness without higher-order modes. Thus improved ways are introduced in the paper to simulate practical array of apertures to reach the result of good agreement and short computing time.

目錄...............................................................Ι
圖表目錄..........................................................III
第一章 序論.........................................................1
1.1 概述.........................................................1
1.2 論文大綱.....................................................3
第二章 等效傳輸線方法(ETL)的介紹....................................4
2.1 ETL推導......................................................4
2.2 ETL方法模擬驗證.............................................10
第三章 陣列槽孔ETL方法的介紹及模擬................................13
3.1 陣列槽孔ETL方法的介紹......................................13
3.2 陣列槽孔ETL方法之模擬驗證..................................16
3.3 模態及位準改善..............................................19
3.4 加入模態及位準修正之ETL方法模擬驗證........................21
3.5 FDTD與ETL運算時間討論......................................25
3.6 電場在不同極化方向的討論....................................27
第四章 非中心陣列槽孔ETL方法之修正及模擬..........................31
4.1 偏移陣列槽孔之修正分量......................................31
4.2 偏移陣列槽孔之模擬驗證......................................34
4.3 多個陣列槽孔之阻抗修正......................................40
4.4 多個陣列槽孔之模擬驗證......................................41
第五章 運用ETL模擬奇特排列之陣列槽孔..............................47
5.1 奇特排列陣列槽孔之處理方法..................................47
5.2 運用ETL快速模擬飛鏢形之陣列槽孔............................62
第六章 提高陣列槽孔遮蔽率之討論....................................65
6.1 陣列槽孔4分之1切割偏移....................................65
6.2 相同總面積之遮蔽率比較......................................67
第七章 結論........................................................70
參考文獻...........................................................71

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