在ZigBee WSNs(wireless sensor networks)的研究中，不少學者偏向於路由(routing)研究、定位系統(locating)研究及實作自動化系統(automation)，鮮少有學者專注研究網路的自我修復或者網路的重新組織等相關議題。ZigBee為一種無線短距離低速率傳輸技術，網路中的節點在傳送資料時，若經過多個節點來路由此資料，所造成的延遲時間將會變多，而大部分的學者皆以修改路由機制的方式來改善這類型的問題，在此，本文是以平衡網路階層的方式進行處理，主要是藉由剛加入網路中的路由器進行搜尋1-hop內的網路，判斷網路階層相差2以上的節點則需要進行重整機制。雖然，ZigBee Alliance的規範中明確的說明了網路的自我組織，其處理程序只針對一開始建立網路時所實行，並非針對整個網路的維護作重組機制。本文將對此提出一個可以減少整體性hop數，這相當於是減少了傳輸延遲時間的方法，主要針對一般網路節點佈置先後順序所導致的不平衡樹狀拓樸的情況，所實行的重新組織動作。模擬結果發現本文所提出的方法確實能改善效能，並且藉由不同的環境參數，能夠產生不一樣的改善能力，而本文在100x100公尺的環境下所得到最佳改善效能為無線範圍半徑10公尺的條件下。

Most research on the area of ZigBee WSNs (wireless sensor networks) focuses on routing, locating, and self-automation system implementation. Other relevant topics such as network self-healing or reorganization are critical yet rarely studied. ZigBee is a low-distance and low-rate wireless transmission mechanism. More delay time is caused when a given data routes through too many nodes during transmission. Most research solves this problem by repairing the routing mechanism. Yet, this thesis proposes to apply the concept of balancing the whole network to counter this problem. When a new router joins a network, it searches through the whole one-hop network and network reorganization is performed if the level difference is 2 or above in the network. Although network self-organization is stated in ZigBee Alliance, it is performed only at the time when a ZigBee network is originally constructed. The reorganization does not apply to the maintenance of already-constructed networks. The main concept of the proposed approach is to reduce the overall number of hops during data transmission, which consequently reduces the overall data transmission time. This approach is particularly effective for those networks that have been updated by outgoing and incoming router nodes and have therefore become unbalanced network structure. The simulated experiments conducted in this thesis have shown the network performance has been well improved by the proposed approach.

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