分散式無線網路已在許多方面為人類的生活提供了很多便利。在過去之中，分散式無線網路是由人為控制的，但這種方式並不文明以及科學，在分散式無線網路裡，分佈的節點之間能夠保持協調，時間同步扮演著很重要的腳色。時間同步對於分散式無線網路是相當重要的一環，因為在MAC層仰賴準確的時間資訊能夠更有效率的收集資料和節省電力消耗。如果缺乏有效的時間同步演算法，時間同步的錯誤在分散式無線網路中是難以避免的。基本上，時間同步的方法可以分為兩大類: 依據參考節點的時間同步和分散式的時間同步。在依據參考節點的時間同步方法中，非參考點的時間資訊必須向參考點的時間資訊校準。另一方面，在分散式的時間同步方法中，每一個在網路中的節點遵循著相同的分散式演算法而不需要依據參考節點校準時間。
　　在這篇論文中，我們解決了在嵌入式分散式無線網路系統中時間同步的問題。為了應對這個挑戰，在這個環境下我們提出了一個分散式時間同步的協議。為了達到節省電力和時間同步的目的，系統依據了聰明的時間模式設定有效的切割時間序列。

Distributed wireless networks have provided many conveniences for human life in many ways. In traditional, distributed wireless devices are controlled by people, but this is not civilized and scientific. Time synchronization is significant in distributed wireless networks to maintain coordination among distributed network nodes. Global clock synchronization is important to distributed wireless networks that require accurate timing information for data collection and energy conservation in media access control layer protocols. A synchronization error is inevitable in distributed wireless networks, due to be short of effective synchronization algorithms. Basically, clock synchronization can be divided into two types. Legacy solutions are the reference node based clock synchronization solution and the distributed clock synchronization solution. In the reference node based clock synchronization, non-reference nodes tune to the clock information distributed by reference nodes. On the other hand, the distributed clock synchronization, all nodes in the network perform the same distributed algorithm without reference nodes.
In this thesis, we design to solve the time synchronization problems for the embedded distributed wireless devices. To address these challenges, we propose a distributed clock synchronization protocol for this environment. For the purposes of power saving and synchronizing time, the system separates time sequence by using a smart time pattern setting.

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