介質共振器天線(DRA)比起傳統微帶天線有許多吸引人的特性，像是尺寸小、低姿態、輕、容易激發，在高頻段擁有高輻射效率。隨著DRA受到越來越多的注目，理論分析已經不足以滿足人們對於分析介質共振器的需求。
因而許多研究人員以數值分析的方法，如時域有限差分法(FDTD)、動差法(MoM)、有限元素法(FEM)等方法來分析模擬介質共振器天線。本論文說明比較了FDTD與MoM在模擬DRA上的差異性，並以FDTD去模擬分析各種不同結構的DRA。
對於DRA設計方面，本文以理論近似公式求得DRA尺寸的概略值，並以FDTD做精確的分析，最後本文實際去設計一個工作在5.8GHz的DRA，並以一種L形微帶線來增大DRA的阻抗頻寬。由以上的研究希望能建立出快速且準確的一套程序來求得DRA的共振頻率、工作頻寬與遠場場形圖，以縮短工程師設計DRA的時間。

Dielectric resonator antennas(DRAs) offer some attractive characteristics over conventional microstrip antennas, such as small size, low profile, light weight, ease of excitation, and high radiation efficiency at higher frequency bands. Since DRAs attract more and more attention, theoretical analysis have been insufficient to simulate various configurations of dielectric resonator antennas.
Therefore some researchers introduce numerical methods to analyze DRAs, such as Finite Difference Time Domain (FDTD) method, Method of Moment (MoM), Finite Element Method (FEM). In this author, we apply two kinds of methods, including FDTD and MoM, to analysis DRA and compare the results applied these two methods. Then we simulate various configurations of dielectric resonator antennas using FDTD method.
About designing the DRA construction, in this author we applied an equivalent approach to solve approximate dimensions of DRAs, and then we obtain accurate dimensions using FDTD method. In this author，a DRA work at 5.8GHz have been proposed, then we using a L-shaped patch to increase impedance bandwidth. Above all, we hope to built a fast and accurate procedure to solve the resonant frequency, bandwidth, and far field pattern of DRAs. And to supply the engineer to reduce time consume in design DRAs.

目錄

第一章 序論
1.1 研究動機與目的...........................................................................................1
1.2 論文大綱.......................................................................................................4
第二章 介質共振器天線
2.1 介質共振器發展簡介...................................................................................5
2.2 介質共振器天線簡介...................................................................................7
2.3 介質共振器天線的參數.............................................................................12
2.3.1 天線參數....................................................................................12
2.3.2 介質共振器參數........................................................................13
2.3.3 介質共振器的介電常數............................................................14
2.3.4 介質共振器的品質因子............................................................15
2.3.5 共振頻率溫度係數……............................................................16
2.4 介質共振器天線的特性.............................................................................17
第三章 數值分析方法
3.1 介紹.............................................................................................................20
3.2 時域有限差分法.........................................................................................20
3.2.1 FDTD公式推導........................................................................21
3.2.2 Courant穩定準則......................................................................25
3.2.3 阻抗性電壓源與電阻模擬........................................................26
3.2.4 吸收邊界條件............................................................................28
3.2.5 細導線修正公式........................................................................29
3.2.6 近遠場轉換................................................................................31
3.2.7 FDTD曲狀介質結構的處理....................................................33
3.3 動差法.........................................................................................................36
3.4 有限時域差分法與動差法的比較.............................................................39
第四章 運用FDTD模擬介質共振器天線
4.1 矩形介質共振器天線.................................................................................44
4.1.1 微帶線饋入的矩形介質共振器天線........................................44
4.1.2 微帶線貼面饋入的矩形共振器天線........................................47
4.2 圓柱形介質共振器天線.............................................................................48
4.3 半球形介質共振器天線.............................................................................51
4.4 實做量測矩形介質共振器天線.................................................................54
4.5 槽孔耦合….................................................................................................58
4.6 同軸探針耦合….........................................................................................59
4.7 介質損耗與接地面尺寸效應….................................................................61
4.8 介質共振器與饋入結構之間的耦合.........................................................64
第五章 介質共振器天線之設計
5.1 半球形介質共振器天線.............................................................................67
5.2 圓柱形介質共振器天線.............................................................................69
5.3 矩形介質共振器天線….............................................................................71
5.4 介質共振器天線設技實例.........................................................................74
5.5 寬頻化的介質共振器天線.........................................................................75
第六章 結論............................................................................................................78

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