臺灣博碩士論文加值系統

本論文提出一個可應用於WiFi及WiMAX操作頻帶的槽孔耦合天線，此天線結構是以單一SMA單饋入的方式，其中饋入線形狀使用倒L形，讓原本只有單一垂直分量的天線產生另一水平分量以達到圓極化的特性；基板上層由兩個相對的L形槽孔組成，使用雙L形槽孔的設計可以達到寬頻的效果，且不需額外的匹配電路就能達到阻抗匹配；槽孔上方堆疊一正方形貼片可以增加天線增益。經由實驗結果得到阻抗頻寬得到19.6％（2.26GHz~2.75GHz），3dB軸比頻寬16％（2.3 GHz-2.7GHz），天線增益 2.3~2.7Ghz均在6dBic以上，最大增益 9.3dBic。

An aperture-coupled patch antenna is presented. The aperture is composed of two L-shaped-like slots and is proximately-fed by an L-shaped-like strip.
The L-shaped-like strip is first coupled to the first slot through its vertical arm , then serially coupled to the second slot through its horizontal arm.
The length of the vertical and horizontal arms of the L-shaped strip are found highly correlated to the axial- ratio bandwidth of the antenna. The center frequency in the return-loss plot of the antenna is also influenced by the two lengths. The optimized antenna has a return-loss bandwidth of 19.6 % (2.26-2.75 GHz) and an axial-ratio bandwidth of 16 % (2.3-2.7 GHz).

誌 謝 i
ABSTRACT ii
中文摘要 iii
目錄 iv
圖目錄 vi
表目錄 vii
第一章 緒論 1
1.1 研究背景及動機 1
1.2 WiFi 802.11簡介 2
1.3 WiMAX 802.16簡介 5
1.4 論文架構 6
第二章 天線理論 7
2.1 反射損失(Return Loss) 7
2.2 天線輸入阻抗(Input Impedance)與電壓駐波比(VSWR) 8
2.3 天線增益(Antenna Gain) 9
2.4 軸比(Axial Ratio) 10
2.5 輻射場形(Radiation Pattern) 10
2.6 圓形極化原理 11
2.7 槽孔耦合天線 13
第三章 天線設計和分析 16
3.1 天線設計架構 16
3.2 L形槽孔耦合天線設計和分析 19
3.2.1 FY長度變化分析 21
3.2.2 LX長度變化分析 23
3.2.3 LY長度變化分析 25
3.3 雙L形槽孔耦合天線設計和分析-垂直饋入 27
3.4 雙L形槽孔耦合天線設計和分析-L形饋入 30
3.4.1 FX FY長度變化分析 31
3.4.2 LX長度變化分析 34
3.4.3 LY1長度變化分析 36
3.4.4 LY2長度變化分析 38
第四章 天線模擬與量測 41
4.1 模擬與量測數據結果比較 41
4.2 電流分佈與輻射場型 45
第五章 結論 53
附錄 54
參考文獻 59

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