近年來，發展多頻道媒體存取協定已受到極大的關注與討論，並被認為是開發頻寬利用率最有效的方法。在發展多頻道通訊協定時所遭遇的最大挑戰便是主機會面問題(Rendezvous Problem)與多頻道隱藏主機節點問題(Multi-Channel Hidden Terminal Problem)。在過去的研究中，為會面問題，使所有主機在一相同的窄頻會面，造成同時段其它頻道的頻寬利用率降低。本論文提出一多頻道MAC協定，以階梯式的頻道模型及Home Channel概念，不但解決多頻道的主機會面與多頻道隱藏主機節點問題，並將會面的主機平均打散在各個頻道與時間，充份利用頻寬資源以增加網路吞吐量。實驗顯示，本論文所提出的協定可有效增加頻寬利用率，並提昇網路效能。

Multi-channel MAC protocols aim to exploit frequency resources for increasing the overall throughput of wireless Ad-Hoc networks. The most common challenge for developing the multi-channel MAC protocols is the well-known rendezvous problem. In literature, some studies assumed that each device equips with one additional antenna, staying on the control channel for negotiating the channel for data exchange. However, the hardware cost has been increased. Some other works ask all devices participating in ATIM window of a predefined channel, competing for the reservation of data slots for data exchange. However, the bandwidth utilization is low since the ATIM window of all channels other than the predefined channel are not used. This paper presents an Advanced Stepwise Multi-channel MAC Protocols, called ASMC-MAC, for the Wireless Ad Hoc Networks. The proposed ASMC-MAC is developed based upon single antenna and applies stepwise channel model with home channel concept to exploit the multi-channel bandwidth resource. Performance results reveal that the proposed ASMC-MAC outperforms existing multi-channel MAC protocols in terms of network throughput, packet collision ratio, packet delay time, packet discarding, and fairness index.

目錄
圖目錄	VI
表目錄	VII
第一章、	簡介	1
第二章、	相關研究	5
第三章、	環境假設與問題描述	8
3.1	環境假設	8
3.2	問題描述	8
第四章、	Channel Model and Frame Structure	13
4.1	The Stepwise Channel Model	13
4.2	The Frame Structure	15
第五章、	The Proposed ASMC-MAC Protocol	17
5.1	Rendezvous in Stepwise Channel Model	17
5.2	Control Period Design	18
A.	Receiver Declaration Window (RDW)	18
B.	Negotiation Window (NW)	22
5.3	Data Period Design	28
第六章、	實驗模擬及結果	31
6.1	Simulation Environment	31
6.2	Simulation Results	32
第七章、	結論	45
參考文獻	46
附錄-英文論文	48

圖目錄
圖 (1) The proposed stepwise channel model.	15
圖 (2) The frame structure of the ASMC-MAC.	16
圖 (3) The scheduling confliction of control period.	19
圖 (4) To avoid the scheduling confliction control period.	22
圖 (5) The scheduling confliction of data period.	25
圖 (6) Channel switching during Data Period.	28
圖 (7) To avoid the scheduling confliction control period.	29
圖 (8) 3個頻道時，主機數量對網路吞吐量的影響。	34
圖 (9) 6個頻道時，主機數量對網路吞吐量的影響。	35
圖 (10) 不同頻道數的環境下，主機數量對網路吞吐量的影響。	37
圖 (11) 模擬場景中主機佈建的設定分為兩種情境。	38
圖 (12) 場景中主機均勻佈建對網路吞吐量的影響。	39
圖 (13) 場景中主機集中佈建對網路吞吐量的影響。	41
圖 (14) 不同的頻道數與packet arrival rate對Packet Delay的影響。	42
圖 (15) Control/Data 比例與頻道數的改變對網路吞吐量的影響。	43
圖 (16) 是否處理CPSC問題與DPSC問題對於網路吞吐量的影響。	44

表目錄
Table I. 符號表	8
Table II. 實驗參數	32

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