近年來無線網路的蓬勃發展，日常生活中隨處可見的行動裝置也能夠使用無線網路進行資料的傳輸，使得各種無線設備不斷地推陳出新，因此無線網路的技術也不斷提升、改變。在無線區域網路(Wireless Local Area Networks, WLANs)的範疇當中，可以說使用性非常之高。在IEEE 802.11ac標準中提出了新的技術提升無線網路的傳輸速度，並達到一高速網路的環境。本論文中，主要分析兩個存取點在使用不同頻寬做為傳輸時，根據兩個存取點之間的距離，對彼此之間的傳輸所產生的影響與結果，使用分析數據所產生的參數(碰撞組合、公平競爭組合、Degree數與達成平行傳輸所需要的頻道數量)來進行分群，透過分析參數以及本論文所擬訂的分群機制，可以使得多個存取點得以同時進行傳輸，最後再透過有效的頻道配置方法，達到碰撞避免及平行傳輸。

With the rapid development of wireless networks, the number of channels that can be used in a large number of transmission can be said to be quite small. Therefore, how to use effective channel configuration methods to improve the overall network performance and mitigate data collisions. And further to achieve the purpose of parallel transmission.
This paper investigates the allocation problem in dense deployed IEEE 802.11ac wireless local area networks (WLANs). How to use the effective channel allocation method to improve the network as performance, ease data collision problem, and further achieve the purpose of parallel transmission. In this paper, the main analysis of two access points in the use of different bandwidth as a transmission, according to the distance between two APs, the transmission between each other and the results of the use of analytical data generated. By analyzing the parameters and the grouping mechanism proposed in this paper, multiple access points can be transmitted at the same time.

目錄	
第1章	緒論	1
1.1	前言	1
1.2	研究動機與目的	1
1.3	研究方法	2
1.4	論文架構	2
第2章	背景知識	3
2.1	IEEE 802.11ac 基本介紹	3
2.1.1	頻道捆束技術(Channel bonding)	5
2.1.2	IEEE 802.11ac存取方式	6
2.1.3	IEEE 802.11ac傳輸模式	7
2.1.4	頻道靈敏度(Clear Channel Assessment)	8
2.2	相關文獻	11
第3章	預備知識	13
3.1	問題陳述	13
3.2	相關假設	19
3.3	相關定義	20
第4章	研究方法	21
4.1	基本理念	21
4.2	參數計算與流程演繹	22
4.2.1 參數計算	22
4.2.2 分群流程演繹	25
4.3	分群方法	27
4.3.1 分群的步驟演示	27
4.3.2 分群的運作方式	28
4.4	配置方法	31
第5章	效能分析	33
5.1	模擬場景與參數	33
第6章	結論	39
參考文獻	40
附錄A			43 
圖目錄
圖 1 ISM 2.4GHz band	3
圖 2 ISM 5GHz band 及頻道捆束技術	4
圖 3 IEEE 802.11ac存取方式	6
圖 4 靜態頻道存取模式	7
圖 5 動態頻寬存取模式	8
圖 6 隱藏頻道問題示意圖	11
圖 7 網路拓樸	13
圖 8 頻道配置問題(Channel Allocation Problem)	14
圖 9 單向隱藏頻道問題(Single-Direction Hidden Channel Problem)	15
圖 10 單向隱藏頻道問題(Single-Direction Hidden Channel Problem)	16
圖 11 雙向隱藏頻道問題(Double-Direction Hidden Channel Problem)。	17
圖 12 雙向隱藏頻道問題(Double-Direction Hidden Channel Problem)。	18
圖 13 基本理念	21
圖 14 網路環境	24
圖 15 IEEE 802.11ac密集網路佈建環境圖	27
圖 16 分群步驟	30
圖 17 頻道配置步驟	31
圖 18 頻道配置成果	32
圖 19 五個AP之模擬環境	34
圖 20 五個AP的環境下之網路吞吐量比較(2秒)	34
圖 21 五個AP的環境下之網路吞吐量比較(10秒)	35
圖 22 封包遺失率之比較	36
圖 23 十五個AP之模擬環境	37
圖 24 十五個AP的環境下之網路吞吐量比較	37
圖 25 封包遺失率之比較	38
表目錄
表 一、頻道靈敏度(Clear Channel Assessment)	9
表 二、參數計算	23
表 三、模擬參數	33

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