本論文提出應用於終端裝置之低姿勢背部接地面連體開槽孔天線設計，低姿勢天線的定義為天線高度在1 mm (約為3300 MHz的0.011λ)以內，因此能整合於終端裝置之介質機殼，不會額外增加介質機殼的厚度。第一個設計為涵蓋3300 ~ 4200 MHz之5G低姿勢接地共面波導饋入連體開槽孔MIMO四天線設計，為了簡化四天線結構，結合開槽孔天線加寬之閉口端，使四個開槽孔天線為連體結構。第二個設計為整合低姿勢帶線饋入連體開槽孔及短路平板天線形成寬頻WLAN MIMO四天線設計，四天線設計於完整接地面，利用帶線耦合激發開槽孔天線模態及槽孔兩側之一的短路平板天線模態，整合開槽孔與短路平板天線涵蓋5150 ~ 5875 MHz，再將第二個設計為基礎延伸開發六天線與八天線設計，詳細的天線設計原理將在本論文中作說明。

In this dissertation, the low-profile ground-backed conjoined open-slot antennas for future terminal devices are presented. The antennas are very low profile with only 1 mm in height (about 0.011λ at 3300 MHz) or less, thus it can be integrated within the casing of the devices without occupying inner volume therein. Four open-slot antennas are end-widened and conjoined to achieve wide bandwidth yet compact size. The first design is fed using the grounded coplanar waveguide (GCPW) to achieve a wideband operation for 4 × 4 fifth-generation (5G) multi-input multi-output (MIMO) operation in the smartphone in 3300 ~ 4200 MHz. The second design is fed using the stripline and can generate additional shorted-patch antenna mode to cover wide bandwidth. The stripline-fed ground-backed conjoined open-slot antennas can cover 5150 ~ 5875 MHz for 4 × 4 wireless local area network (WLAN) MIMO operation. For practical applications, the second design can be directly attached to the ground plane of display panel of the mobile device, such as the laptop computer. In order to have more antennas for larger MIMO configuration, the design of stripline-fed ground-backed conjoined open-slot antennas for 4 × 4 MIMO operation are extended for 6 × 6 and 8 × 8 MIMO operations. Higher channel capacities can therefore be obtained. Details of the proposed designs are presented.

論文審定書 i
論文公開授權書 ii
Acknowledgements iv
內頁 vi
中文摘要 vii
English Abstract viii
Table of Contents ix
List of Figures xi
List of Tables xviii
Chapter 1 Introduction 1
1.1 Background and Motivation 1
1.2 Literature Review 3
1.3 Dissertation Organization 13
Chapter 2 Grounded Coplanar Waveguide-Fed Wideband Conjoined Open-Slot Antennas for 4 × 4 5G MIMO Operation in 3300 ~ 4200 MHz 17
2.1 Antenna Structures and Operating Principles 17
2.2 Experimental Results 27
2.3 Integration Study within the Dielectric Back Cover 31
2.4 User’s Hand Effects 36
2.5 4 × 4 MIMO Measurement Study 39
2.6 Extended Study 45

Chapter 3 Stripline-Fed Conjoined Open-Slot Antennas for On-Metal Application with 4 × 4 WLAN MIMO Operation in 5150 ~ 5875 MHz 49
3.1 Antenna Structures and Operating Principles 50
3.2 MIMO Performance Analysis 60
3.3 Extended Study 62
Chapter 4 Stripline-Fed Conjoined Open-Slot Antennas for On-Metal Application with 6 × 6 and 8 × 8 WLAN MIMO Operation in 5150 ~ 5875 MHz 68
4.1 Six-Antenna Structure for 6 × 6 WLAN MIMO Operation in 5150 ~ 5875 MHz 68
4.2 Eight-Antenna Structure for 8 × 8 WLAN MIMO Operation in 5150 ~ 5875 MHz 74
4.3 Experimental Results 79
4.4 MIMO Performance Analysis 82
Chapter 5 Conclusions 86
References 89
Publication List 94

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