本論文提出一種應用於全金屬背蓋平板通訊裝置的LTE/WWAN天線設計。天線設計首先針對低頻頻帶的部分，引用接地面天線的概念，將一結構簡單且尺寸僅為5 x 4 x 40 mm3的單極天線與一可調式匹配電路結合，可調式匹配電路中包含兩個可變電容，透過可變電容的調整可以控制天線共振模態的操作頻率，而整體匹配電路可以改善天線的操作頻寬以及輻射效率。藉由選擇不同電容值，天線可依據使用者的需求操作於特定頻帶，達成在低頻頻帶 (如698~960 MHz) 多頻操作的目的。接著，再引入雙天線的概念，可在不影響低頻表現的情況下，加入一高頻天線結構，使得本天線設計的低頻頻帶與高頻頻帶可以獨立操作；此高頻天線結構為一單極天線與一短路單極天線所組成，透過將兩單極天線的基頻模態合成，可以在高頻涵蓋1 GHz之頻寬；本天線設計在整體高度僅為5 mm，且最大寬度為5 mm下，可涵蓋698~960 MHz及1710~2690 MHz之LTE/WWAN操作；本天線設計因小型化以及結構簡單的特性可容易的與全金屬背蓋平板裝置整合。

An LTE/WWAN antenna for application in the tablet communication device with full-metal cover is presented. By applying the design concept of ground antenna for the low-band operation, the proposed antenna integrates a tunable matching circuit to a simple monopole radiator of size 5 x 4 x 40 mm3 only. The tunable matching circuit includes two variable capacitors. By tuning the variable capacitors, the frequencies of the resonant modes can be controlled, and the operating bandwidth and radiation efficiency of the antenna can be improved with the aid of the complete matching circuit. By choosing different values of the capacitors, the antenna can achieve multiband operation in the desired lower band of 698~960 MHz. Then, by applying the concept of dual antennas, the proposed antenna further integrates with a high-band antenna structure without affecting the performance in the lower band. In this case, the antenna’s lower band and higher band can be independently controlled. The high-band antenna structure is composed of a monopole antenna and a shorted monopole antenna. The combination of the fundamental modes of the two monopole antennas can cover a bandwidth of 1 GHz in the higher band. The proposed antenna can hence cover the LTE/WWAN operation in the 698~960 MHz and 1710~2690 MHz bands with a height of 5 mm only and a width of 5 mm at most. Owing to the small size and simple structure, the proposed antenna can be embedded in the tablet communication device with full-metal cover easily.

目錄 i
圖次 iii
表次 v

第一章 序論 (Introduction)
1.1 研究動機+1
1.2 文獻導覽+2
1.3 論文提要+3

第二章 全金屬背蓋平板通訊裝置天線應用於LTE700/GSM850/900之操作 (LTE700/GSM850/900 Antenna for the Tablet Communication Device with Full-Metal Cover)
2.1 天線設計與技術原理+6
2.2 模擬結果與匹配電路分析+9
2.3 心得與討論+19

第三章 全金屬背蓋平板通訊裝置之LTE/WWAN天線設計 (LTE/WWAN Antenna for the Tablet Communication Device with Full-Metal Cover)
3.1 天線結構與技術原理+22
3.2 模擬結果與參數分析+25
3.3 心得與討論+32

第四章 全金屬背蓋平板通訊裝置之LTE/WWAN天線實驗與分析 (Experiments and Analyses of LTE/WWAN Antenna for the Tablet Communication Device with Full-Metal Cover)
4.1 天線實驗結果與分析+35
4.2 接地面電流與輻射場型分析+40
4.3 心得與討論+43

第五章 結論 (Conclusions)+45

參考文獻 (References)+48
論文著作表 (Publication List)+52

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