展望新興的「5G」(第五代行動通訊)世代，由於採用更高的頻段，所面臨的空間傳播耗損問題更加嚴峻，自然更需要搭配越來越進步的天線波束成型及指向操控技術，以滿足日趨龐大的資訊傳輸需求。傳統的波束指向操控機制，有其共同性缺點：結構複雜，體積龐大，且自身衰減嚴重、成本效益不佳。因此本論文主要針對如何簡化波束操控方式、降低製作成本，並設計實作可應用於5G中 Sub-6G Hz頻段、兼具操控波束指向功能之MIMO天線，作為研究目標。
本論文研究提出了利用「鏡射理論」及「固定式移相網路」等簡易機制，達成操控合成波束指向目的，有別於以往傳統陣列式天線，需要大量複雜的移相器、分波線路、二極體開關及外接直流偏壓、控制線路方能達成操控場型目的。
在天線本體上，以反射用導體平面為輔助，將原本背向輻射所造成的能量浪費，利用鏡射後與主波束同相累加，提升增益值，達到輻射能量最大運用效益，更藉由調整天線本體與反射導體平面間的距離，便可對應產生特定指向需求之高增益波束；另外輔以巴特勒矩陣易於產生固定相位差特性，即可相互擷取所長，互補所短，獲得波寬收攏、指向明確的多波束指向MIMO天線系統。

Looking forward to the emerging "5G" (5th generation mobile networks) generation, due to the adoption of higher frequency bands, the problem of space propagation loss is much more serious. It is necessary to develop the advanced antenna pattern control and beam-forming technology to fulfill the growing demand for communication needs. The traditional beam steering mechanisms have common shortcomings: the structure is complex, the volume is huge, the attenuation is serious and the cost-effectiveness is not good. Therefore, this thesis focuses on how to simplify the beam steering method, reduce the production cost, and design the MIMO antenna that can be applied to the Sub-6G Hz band in 5G and has the beam steering function as the research target.

This thesis proposes simple mechanisms such as "image theory" and "fixed phase shifting network" to achieve the purpose of manipulating synthetic beam steering. It is different from the traditional array antennas which requires a huge number of expensive phase shifters, complex circuit networks, PIN-diode switches, external DC bias and control circuits so that to achieve the purpose of controlling the beam-forming.

For the dipole antenna main body, it is wasted to radiate backward. With the reflection conductor plane, the reflected beam can accumulate in phase with the main beam to increase the gain, thereby achieving the maximum utilization benefit of the radiant energy, and by adjusting the spacing between the dipole and the reflective conductor plane can change the beam pointing direction. In addition, using the advantages of the Butler matrix network to improve the beam width become more narrow. The study results is to realize a novel beam steerable MIMO antenna system.

第一章 序論 1
1.1 研究背景 1
1.2 文獻導覽 3
1.3 研究方法及目的 3
1.4 內容提要 4
第二章 天線波束指向操控方式探討 7
2.1 前言 7
2.2 陣列式天線輻射場型波束指向原理說明 7
2.3 常見改變相位差方式 12
2.3.1鐵鹽材質移相器 12
2.3.2晶體式移相器 13
2.3.3切換傳輸線式移相器 14
2.3.4頻控陣列天線 15
2.4 本研究所使用波束指向操控方式 18
第三章 利用鏡射理論改變波束方向之天線分析及實作 19
3.1 前言 19
3.2 鏡射理論 19
3.2.1偶極天線垂直懸浮於導體平面分析 22
3.2.1.1不同的距離h所造成的合成波束形狀改變分析 23
3.2.2偶極天線水平懸浮於導體平面分析 25
3.3 以偶極天線搭配鏡射理論實現可控波束之實作 29
3.3.1基本單一偶極天線 29
3.3.2單邊抑制偶極天線對運用於波束指向之設計及實作 31
3.3.2.1模擬及實測波束指向變化 33
3.3.3改良式單邊抑制偶極天線對設計與實作 38
3.3.3.1天線設計說明 38
3.3.3.2調整天線與反射導體平面距離h改變波束指向方法的模擬及實測 40
3.4 利用陣列組合讓指向波束更加收攏變窄 45
3.5 結論 49
第四章 利用巴特勒矩陣移相網路改變波束方向之分析及實作 51
4.1 前言 51
4.2 巴特勒矩陣原理 51
4.2.1傳統巴特勒矩陣 57
4.3 改良式4X4巴特勒矩陣 58
4.3.1槽孔耦合耦合器原理 60
4.4 改良式4x4巴特勒矩陣實作 63
4.5 搭配天線陣列量測場型指向變化 67
4.5.1「具反射導體平面之偶極天線陣列」結合「改良式巴特勒矩陣」後輻射場型量測結果 67
4.5.2巴特勒矩陣結合單邊抑制天線陣列 71
4.5.2.1實作及量測結果 74
4.6 結論 78
第五章 結論與未來研究方向 81
5.1 結論 81
5.2 未來其他研究方向 82
5.2.1布拉斯矩陣 82
5.2.2沃倫韋伯陣列概念 86
參考文獻 (References) 88

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