本論文提出兩項可應用於金屬機殼智慧型手機之MIMO雙天線及四天線設計，其中第一部分設計包括LTE四天線及WLAN雙天線，第二部份為LTE四天線設計，此兩項設計皆配置於手機短邊，
並利用隔離機制，達成小尺寸高隔離度的MIMO多天線系統。第一部份多天線設計，包含LTE四天線，其中天線一、三可涵蓋LTE低頻824~960 MHz及高頻1710~2690 MHz頻帶，
天線二、四可涵蓋LTE 高頻1710~2690 MHz，而天線二可多涵蓋GPS頻帶，WLAN雙天線五、六可涵蓋WLAN低頻2400~2500 MHz及高頻5000~6000 MHz頻帶。
然而在此一設計中，天線一、二之高頻模態激發時，耦合電流會延著金屬機殼接地面進入兩天線饋入端，增加兩天線高頻頻帶之封包相關係數(ECC)，因此在第二部份之設計中，
在不考慮WLAN頻帶及GPS頻帶操作下，針對LTE四天線進一步設計並優化。此設計利用將天線二環圈天線之短路點設置於兩天線饋入端之間，使結構之一部份可視為隔離支路，
導引兩天線間耦合電流，藉此降低封包相關係數。此設計天線一、三可涵蓋880~960 MHz及1710~2690 MHz頻帶，天線二、四可涵蓋1710~2690 MHz頻帶，
使LTE低高頻分別可應用於2 × 2 MIMO系統及4 ×4 MIMO 系統。

MIMO antennas in the metal-casing smartphone for 2 × 2 and 4 × 4 MIMO operation are presented.
The first design includes four LTE antennas and two WLAN antennas and the second design includes four LTE antennas.
In the two designs, all antennas are disposed at the two short edges of the smartphone. In the first design, Antennas 1 and 3 can cover LTE 824~960/1710~2690 MHz.
Antenna 2 can cover LTE 1710~2690 MHz and GPS operation. Antenna 4 can cover LTE 1710~2690 MHz. Antennas 5 and 6 can cover WLAN 2400~2500/5000~6000 MHz.
However, when Antennas 1 and 2 are excited, a strong coupling between the two antennas occurred in the high band,
which causes a high envelope correlation coefficient (ECC) thereof. Therefore, in the second design,
new four LTE antennas (Antennas 1 and 2 at the top short edge and Antennas 3 and 4 at the bottom short edge) are devised to achieve low ECC and good isolation.
The main feature of the second design is that the radiating metal-frame of Antenna 2 is shorted-circuited to the system ground plane between the two feed ports of Antennas 1 and 2,
so that the shorted metal-frame can also be used to direct the excited surface currents in the system ground plane.
In this case, good isolation and low ECC between two LTE MIMO antennas can be obtained.
In this design, Antennas 1 and 3 can cover LTE 880~960/1710~2690 MHz. Antennas 2 and 4 can cover 1710~2690 MHz.
The four LTE MIMO antennas can be applied in the 2 × 2 LTE low-band MIMO and 4 × 4 LTE high-band MIMO systems.

論文審定書 i
致謝 ii
中文摘要 iii
英文摘要 iv
目錄 v
圖次 vii
表次 x
第一章 序論 (Introduction)
1.1 研究動機 1
1.2 文獻導覽 2
1.3 論文各章節提要 3
第二章 金屬機殼智慧型手機之MIMO多天線設計 (MIMO Antennas in the Metal-Casing Smartphone)
2.1 天線結構介紹及模擬結果分析討論 5
2.2 實驗結果分析及討論 19
2.3 延伸設計 25
2.4 心得與討論 28
第三章 金屬機殼智慧型手機之低耦合LTE MIMO四天線設計 (Four LTE MIMO Antennas with Low Correlation in the Metal-Casing Smartphone)
3.1天線結構及技術原理說明 30
3.2參數分析討論 40
3.3天線之MIMO效能分析 44
3.4延伸設計 48
3.5心得與討論 51
第四章 結論 (Conclusions) 52
參考文獻 (References) 54
著作表 (Publication List) 57

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