本論文提出應用於智慧型手機之兩正交混合型LTE MIMO天線設計。兩天線(一個開槽孔天線和一個倒F形天線) 彼此為正交配置。其中開槽孔天線是由具有不同長度且互相平行配置於智慧型手機底側的兩個開槽孔所組成。此開槽孔天線是做為LTE/WWAN的主天線，可以操作在698～960 MHz和1710～2690 MHz。而倒F形天線總長度為90 mm且沿著接地面的一側邊配置，並可以放置於智慧型手機的顯示面板及機殼之間的1 mm的窄淨空區間內。此側邊天線可以涵蓋824～960 MHz和1710～2690 MHz的LTE操作頻寬，例如頻帶5、8、10、25和40。由於兩天線為正交方式排列，封包相關係數可以小於0.07。遍歷通道容量在訊雜比為20 dB時可以達到大約9.3～10.7 bps/Hz。本論文會針對MIMO天線的結構和操作機制做詳細的說明，實作成品及數據也會一併討論，同時也會針對加入顯示面板及使用者的手對MIMO特性的影響進行分析。

Two orthogonal hybrid antennas for the LTE MIMO operation in the smartphone are presented. The two antennas (one open-slot antenna and one inverted-F antenna) are disposed orthogonally to each other. The open-slot antenna comprises two open slots of different lengths and is disposed parallel and close to the bottom edge of the smartphone. The open-slot antenna operates in the 698~960 MHz and 1710~2690 MHz bands as a main antenna for the LTE/WWAN operation. The inverted-F antenna has a total length of 90 mm and is disposed along one side edge of the device ground plane. The inverted-F antenna can fit in a narrow ground clearance of 1 mm between the display panel and the casing of the smartphone. The side-edge antenna is able to cover the frequency ranges of 824~960 MHz and 1710~2690 MHz for the LTE operation such as in band 5, 8, 10, 25, and 40. Owing to the orthogonal alignment of the two antennas, good envelope correlation coefficients of less than 0.07 are obtained. The ergodic channel capacity is calculated to reach about 9.3~10.7 bps/Hz at 20-dB signal-to-noise ratio. Details of the MIMO antenna structure and its operating principle are described. Experimental results of the fabricated prototype are presented and discussed. Effects of the display panel and user’s hand on the MIMO performance are also analyzed.

論文審定書 + i
論文公開授權書 ii
Thesis Authorization Letter + iii
Acknowledgements + v
內頁 + vi
中文摘要 + vii
English Abstract + viii
Table of Contents + ix
List of Figures + xi
List of Tables + xiv
List of Abbreviations + xv
Chapter I Introduction + 1
1.1 Background and Motivation + 1
1.2 Literature Review + 5
1.3 Thesis Organization + 7
Chapter II Orthogonal Hybrid LTE MIMO Antennas for the Smartphone + 9
2.1 Structures of the Two Hybrid Antennas + 9
2.2 Operating Principle of the Two Hybrid Antennas + 12
2.3 ECC and Channel Capacity of the Two Hybrid Antennas + 18
Chapter III Experimental Results and Discussion + 23
3.1 Experimental Setup + 23
3.2 Experimental Results + 24
3.3 MIMO Performance + 28
Chapter IV Effects of Display Panel and User’s Hand on the MIMO Performance + 31
4.1 Display Panel Effects + 31
4.2 User’s Hand Effects + 34
Chapter V Conclusions + 45
References + 47

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