為了滿足現今手機需要大量傳輸資料，本論文提出可應用於金屬機殼手機之多天線設計。第一個設計為應用於LTE/WLAN金屬機殼手機之MIMO多天線設計，設計環境為2 mm淨空區且上下短邊框各有兩個斷縫，總共區隔出六個天線，Ant1和Ant3為LTE LB/MB/HB的倒F形天線，涵蓋703～803 MHz/1710～2690 MHz，Ant2為涵蓋GPS、LTE MB/HB的半環圈天線，而Ant4為涵蓋LTE MB/HB的半環圈天線，以上四個天線共可應用於LTE LB 2 x 2 MIMO操作以及LTE MB/HB 4 x 4 MIMO操作，Ant5和Ant6為WLAN半環圈天線可形成WLAN 2 x 2 MIMO系統，但在此多天線架構下，同個短邊框的兩個LTE MB/HB MIMO天線，因為接地面短邊的長度對應到1.9 GHz半波長，表面電流會經由接地面短邊進入另一天線饋入端，所以兩天線在1.71～2.2 GHz有封包相關係數(Envelope Correlation Coefficient)過高的問題。所以第二個設計移除六天線中的WLAN天線，優先設計可降低封包相關係數，並可應用於金屬機殼手機之寬頻自我解耦合LTE MIMO天線，此設計的短邊框有三斷縫，以分隔出兩個天線的輻射部且與長側邊框分離，上短邊框兩天線為Ant1和Ant2，下短邊框兩天為Ant3及Ant4，Ant1及Ant3為涵蓋LTE LB/MB/HB的環圈天線，Ant2及Ant4為涵蓋LTE MB/HB的倒F形天線，而利用此天線本身的結構來達到寬頻解耦合的效果，Ant2及Ant4的倒F形天線短路端置於同短邊框兩天線之間，可用於導引接地面短邊的表面電流，使得兩天線在接地面短邊的電流較不互相干擾，改善雙天線的隔離度以及降低封包相關係數，使得封包相關係數在1.71～2.69 GHz可達0.2以下，使此四天線在1710～2690 MHz可應用在4 x 4 LTE MB/HB MIMO系統，增加通道容量，提高傳輸速率，並且兩低頻天線則可應用在2 x 2 LTE LB MIMO系統。

This thesis presents two designs of MIMO antennas for increasing the data transmission rate in the metal-casing smartphone. The first design is on the multiple frame antennas for the LTE/WLAN MIMO operation, which includes six antennas and is disposed in the 2-mm metal clearance at the top and bottom edges of the smartphone. The six antennas include a half-loop frame antenna for GPS/LTE M/HB (Ant2), a half-loop frame antenna for LTE M/HB (Ant4), two inverted-F antennas for LTE L/M/HB (Ant1, Ant3), and two half-loop frame antennas for WLAN (Ant5, Ant6). Ant1, Ant2, and Ant5 are disposed at the top edges. Ant3, Ant4, and Ant6 are disposed at the bottom edges. The top and bottom edges have similar designs. Ant1/3 and Ant5/6 can be applied for the 2 × 2 LTE LB MIMO and 2 × 2 WLAN MIMO, respectively. Furthermore, the 4 × 4 LTE M/HB MIMO can also be obtained by applying Ant1, Ant2, Ant3 and Ant4. However, the aforementioned design has high ECC values in 1.71～2.2 GHz for the 4 × 4 LTE M/HB MIMO operation. In order to resolve this problem, self-decoupled wideband antennas for the LTE MIMO operation is presented as the second design. This design includes four antennas disposed in the 2-mm metal clearance at the top and bottom edges of the smartphone. A loop frame antenna for the LTE L/M/HB (Ant1) and an inverted-F frame antenna for the LTE M/HB (Ant2) are disposed at the top and bottom edges respectively. In the proposed design, the excited surface currents on the ground plane can be directed to the frame section of Ant2, which makes the ECC of two antennas in the LTE M/HB significantly improved. Moreover, Ant1 and Ant3 can be applied in the 2 × 2 LTE LB MIMO operation. Ant1 to Ant4 can be applied in the 4 × 4 LTE M/HB MIMO operation.

論文審定書 i
致謝 ii
中文摘要 iii
英文摘要 iv
目錄 v
圖次 vi
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 應用於LTE/WLAN金屬機殼手機之MIMO多天線設計 (Multiple Frame Antennas for the LTE/WLAN MIMO Operation in the Metal-Casing Smartphone)
2.1 天線結構介紹及操作機制 5
2.2 天線模擬及實驗量測數據 16
2.3 延伸設計 22
2.4 心得與討論 26
第三章 應用於LTE金屬機殼手機之自我寬頻解耦合MIMO天線設計
(Self-Decoupled Wideband Antennas for LTE MIMO Operation in the Metal-Casing Smartphone)
3.1天線結構及操作機制 28
3.2 MIMO效能分析 36
3.3心得與討論 38
第四章 結論 (Conclusions) 47
參考文獻 (References) 49

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