在網路普及使用的情況下，出現無線頻寬不足的問題。節點傳輸速率降低的同時，也反應出在有限的頻寬上，網路產生壅塞的情形。因此如何有效使用頻寬已經成為許多學者研究的目標。在多種可增進網路效能的技術中，其中的兩種方式分別是使用多重頻道(Multi-Channel)和進行電量控制(Power Control)。本篇論文希望藉由合併此兩種技術，利用空間的切割(多重頻道)和同一空間內並行傳輸(電量控制)，以減少壅塞的情況並增進網路效能。在頻道挑選方面，傳輸對可能面臨，當進行電量控制後，有多個頻道可以使用時，考量傳輸對間相對位置的干擾情況，作為頻道挑選的依據。在論文的最後，透過實驗模擬的結果得知，當此兩種技術合併使用時且透過論文內的頻道挑選機制，可以大大提升網路效能。

The bandwidth resource is a precious resource in wireless ad hoc networks. Many researches have been proposed to increase the utilization of bandwidth by using multi-channel mechanism or power control mechanism. In order to enhance the bandwidth utilization, power control and multi-channel mechanisms are both used in this paper. However, the different power should be used to transmit data on different channels due to the different network environments on each channel. In such a case, how to select a suitable channel to mitigate interference is an important issue. Therefore, this paper proposes a MAC protocol, named SMART MAC protocol, which selects a suitable channel for data transmission. The simulation results show that the proposed protocol can provide better network throughput.

Table of Contents
第1章	緒論	- 1 -
1.1	前言	- 1 -
1.2	研究動機與目標	- 1 -
1.3	研究方法	- 2 -
1.4	論文架構	- 3 -
第2章	IEEE 802.11背景與相關論文之研究	- 4 -
2.1	IEEE 802.11 Standard	- 4 -
2.1.1	作法	- 4 -
2.1.2	優缺點	- 5 -
2.1.3	結論	- 5 -
2.2	Multi-Channel MAC for Ad Hoc Networks: Handling Multi-Channel Hidden Terminals Using A Single Transceiver (MMAC)	- 6 -
2.2.1	作法	- 6 -
2.2.2	優缺點	- 9 -
2.2.3	結論	- 9 -
2.3	POWMAC: A Single-Channel Power-Control Protocol for Throughput Enhancement in Wireless Ad Hoc Networks	- 10 -
2.3.1	作法	- 10 -
2.3.2	優缺點	- 12 -
2.3.3	結論	- 12 -
2.4	A Multi-channel MAC Protocol with Power Control for Multi-hop Mobile Ad Hoc Networks (DCA-PC)	- 13 -
2.4.1	作法	- 13 -
2.4.2	優缺點	- 13 -
2.4.3	結論	- 14 -
第3章	預備知識	- 15 -
第4章	SMART: A Distributed Spatial-aware Multi-channel Assignment with Radio Transmission Power Control MAC Protocol for Multi-channel Wireless Ad Hoc Networks	- 17 -
4.1	SMART MAC Protocol	- 18 -
4.1.1	Network Model	- 18 -
4.1.2	Scheduling Interval	- 20 -
4.1.3	Power Control Strategy	- 21 -
4.1.4	Reduce Channel Wastage	- 24 -
4.1.5	Avoid Excessive Interference	- 25 -
4.1.6	Increase Interference Tolerance	- 26 -
4.1.7	Channel Assignment Policy	- 27 -
第5章	實驗	- 29 -
5.1	比較分析	- 29 -
第6章	結論	- 35 -
Reference	- 36 -
附錄－英文論文	- 39 -

List of Figures
Fig. 1.	電量調整對於環境影響之實驗場景。	- 2 -
Fig. 2.	電量調整對於環境影響。	- 3 -
Fig. 3.	802.11 DCF Mode[11] 。	- 5 -
Fig. 4.	802.11 Power Saving Mode[2] 。	- 6 -
Fig. 5.	MMAC通訊協定架構[2] 。	- 7 -
Fig. 6.	在多重頻道上遺失控制封包。	- 8 -
Fig. 7.	POWMAC通訊協定基本架構。	- 11 -
Fig. 8.	Data Collision and ACK Collision 示意圖。	- 11 -
Fig. 9.	解決遺漏封包的問題。	- 19 -
Fig. 10.	電量控制後產生隱藏節點問題。	- 19 -
Fig. 11.	TPCS Interference Model。	- 21 -
Fig. 12.	Channel Wastage。	- 25 -
Fig. 13.	造成在節點A過多的干擾。	- 26 -
Fig. 14.	過多的 Idle Interval。	- 26 -
Fig. 15.	Nest的使用目的。	- 28 -
Fig. 16.	Active Transmission Stations。	- 31 -
Fig. 17.	封包成功接收的比率。	- 32 -
Fig. 18.	Aggregate Network Throughput。	- 33 -
Fig. 19.	Different Packets Arrival Rate。	- 34 -

List of Tables
Table 1. 實驗相關參數。	- 29 -

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