無線感測網路 (Wireless Sensor Networks) 由於在各領域上都擁有廣泛的應用，在近年來，已成為一個熱門的討論議題。在其眾多應用當中，又以軍事、醫療、動態追蹤、家庭應用等最為人所熟知。由於感測器受限於電量、通訊範圍、記憶體容量、及運算能力等，設計一套資料蒐集的演算法時就需要同時考量感測器的傳播次數、資料延遲時間、網路的壽命等。
在資料收集的問題當中，傳統的靜態接收器會導致其周圍的感測器電量消耗較高，而使得這些感測器較早沒電讓網路不連通，造成資料產生後無法傳遞至接收器。為了解決這個問題，使用移動式接收器便能使得網路耗能更平衡。我們提出了DMRT(Data collection with Mobile sink using weighted Root rendezvous Tree)演算法。利用現有的connected dominating set (CDS) 演算法，組成一個骨架，在其之上建立一棵樹，利用此架構搭配移動式接收器來收集資料。
最後，我們將與常見的演算法作模擬比較，當事件數量、溝通半徑、接收器移動速度等的改變，其結果可看出在整體耗能、資料延遲時間與網路壽命，本篇所提出之演算法皆能勝過目前的演算法。

Data collection is an important issue in wireless sensor networks. A mobile sink can balance network load; however, mobile sinks introduce challenges related to uncertain movement direction and speed. In this paper, we propose the data collection that takes advantage of a virtual backbone based on a connected dominating set and a rendezvous tree. In the proposed method, sensor nodes work independently to construct a path to the mobile sink without expensive GPS devices. Simulation results show that our algorithm can significantly reduce control packets, decrease data delivery delay, and increase network lifetime over state-of-the-art methods.

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