臺灣博碩士論文加值系統

近年來無線通訊追求更高的傳輸速率已滿足使用者傳輸與下載資料之需求，已經有研究將多輸入多輸出天線應用在無線傳輸系統上可以增加無線通道的傳輸速率和可靠性，但是在MIMO天線的耦合會影響無線通道的傳輸速率，傳統上兩天線間距離在半波長以上會有較小的耦合，因此將MIMO天線整合在體積較小行動通訊上，將造成天線相互耦合嚴重的問題。

本論文中第一部分設計WLAN/WiMAX天線包含了WLAN的2.4GHz (2.4-2.48GHz)以及WiMAX的2.5GHz (2.5-2.7GHz)；3.5GHz (3.4-3.7GHz)，並且在接地面利用倒U型槽孔及omega型槽孔來降低MIMO天線耦合，其結果在MIMO天線的耦合在所操作頻段都在-20dB以下，第二部分以平面天線做設計並且設計在WLAN/WiMAX包含了WLAN的2.4GHz (2.4-2.48GHz)、5.2/5.8GHz (5.15-5.35GHz/5.725-5.825GHz)以及WiMAX的2.5GHz (2.5-2.7GHz)、3.5GHz (3.4-3.7GHz)；5.5 GHz (5.25-5.85 GHz)，在MIMO天線的耦合在所操作頻段都在-20dB以下。

In recent year, wireless communications systems require transmission of higher and higher data rates to foster various multimedia services. The multiple-input multiple-output (MIMO) antennas system has been studied to increase wireless channel capacity and reliability. The mutual coupling of MIMO antennas affects the capacity of the wireless channel. Traditionally, the minimal mutual coupling distance between antenna elements needs to be at least one half wavelength. When MIMO antenna system is used in miniature mobile device, the problem of mutual coupling becomes even more serious.

In the first part of this thesis we propose a WLAN/WiMAX antenna that can be operated in 2.4 GHz (2.4–2.48 GHz) WLAN band; 2.5 GHz (2.5–2.7 GHz) and 3.5 GHz (3.4–3.7 GHz) WiMAX band. We use the inverted U slot band notch and omega slot band notch to reduce the mutual coupling in MIMO antennas. Our design is able to reduce the mutual coupling to be less than –20 dB in all interested bands. In the second part, we propose a planar WLAN/WiMAX antenna that can be operated in 2.4 GHz (2.4–2.48 GHz), 5.2/5.8GHz (5.15-5.35GHz/5.725-5.825GHz) WLAN band; 2.5 GHz (2.5–2.7 GHz), 3.5 GHz (3.4–3.7 GHz) and 5.5 GHz (5.25-5.85 GHz) WiMAX band and mutual coupling of MIMO antenna is less than –20 dB in all interested bands.

目錄
致謝........................................................................................................................................I
摘要(中文)...........................................................................................................................III
摘要(英文)...........................................................................................................................IV
目錄.......................................................................................................................................V
圖表目錄............................................................................................................................VII
第一章 序論.......................................................................................................................1
1.1 研究動機.......................................................................................................1
1.2 研究方法.......................................................................................................2
1.3 論文大綱.......................................................................................................2
第二章 基本天線理論和簡介.........................................................................................3
2.1 偶極天線.......................................................................................................4
2.2 單極天線.......................................................................................................5
2.3 倒L天線.......................................................................................................7
2.4 倒F天線.......................................................................................................8
第三章 設計WLAN/WiMAX雙頻天線在行動接收端..............................................9
3.1 WLAN/WiMAX簡介................................................................................9
3.2 行動通訊接收端WLAN/WiMAX雙頻天線設計.................................10
3.2.1 設計概念與探討.............................................................................10
3.2.2 WLAN/WiMAX雙頻天線參數對S11探討...............................13
3.3 WLAN/WiMAX雙頻天線實作結果........................................................15
第四章 設計低耦合WLAN/WiMAX天線在PDA應用於MIMO系統.................17
4.1多輸入多輸出(MIMO)系統簡介..............................................................17
4.2 天線間互耦對於MIMO之影響..............................................................18
4.3 設計WLAN/WiMAX天線在PDA之MIMO應用.............................19
4.3.1 設計概念與探討.............................................................................19
4.4 WLAN/WiMAX天線在PDA之MIMO實作結果............................22
4.5 利用倒U型槽孔降低MIMO天線耦合.................................................24
4.5.1 概述..................................................................................................24
4.5.2 設計概念與探討.............................................................................24
4.6 倒U型槽孔WLAN/WiMAX-MIMO天線實作結果............................32
4.7利用Omega型槽孔降低MIMO天線耦合......................................................35
4.7.1設計概念與探討..............................................................................35
第五章 設計低耦合WLAN/WiMAX三頻MIMO天線...........................................38
5.1 行動通訊(PDA) WLAN/WiMAX天線設計概述..................................38
5.2 雙寬頻WLAN/WiMAX天線設計概念與探討.....................................38
5.3 WLAN/WiMAX三頻天線設計概念與探討...........................................42
5.4 WLAN/WiMAX三頻天線之實作結果...................................................45
5.5 WLAN/WiMAX三頻MIMO天線設計概念與探討............................50
5.6 WLAN/WiMAX三頻MIMO天線之實作結果.....................................54
第六章 結論...................................................................................................................62
參考文獻.........................................................................................................................63

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