無線感測網路 (Wireless Sensor Networks) 在各領域上都擁有廣泛的應用，在最近幾年來，已成為一個熱門的討論議題。
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，而使得這些感測器過早耗盡電量讓網路不連通，造成資料產生後無法傳遞至接收器。為了解決這種問題，我們提出一種資料收集方法以中繼跳數為基礎叫做weight based mobile data gathering(WBMDG)，選出一些節點當作rendezvous points(RPs) 給移動接收器收集資料，並且平衡網路負載，使得增加網路壽命。最後，我們將與EEBRHM和SPT-DCA演算法作模擬比較，傳輸半徑、節點數量等的改變，其結果可看出在整體耗能可以有效地降低使延長網路壽命、資料延遲時間。

Data gathering is an important issue in wireless sensor networks. In a Wireless Sensor Networks (WSNs), sensor nodes deliver sensed data back to the sink via multi-hopping. The sensor nodes near the sink will generally consume more battery power than others; consequently, these nodes will quickly drain out their battery energy and shorten the network lifetime of the WSNs. The design of WSNs with mobile sink provides a solution to prolong the network lifetime, which avoids consuming too much battery energy for a specific group of sensor nodes. In this paper, a data gathering approach in WSNs, which is based on the number of relay hops, called weight-based mobile data gathering (WBMDG). In the proposed method, sensor nodes work independently to select several special nodes called rendezvous points (RPs) to the mobile sink. RPs are viewed as temporary points of the mobile sink for data collection, and can be reselected after a definite period. Simulation results show that our algorithm can significantly balance the load of the whole network, decrease data delivery delay, and increase network lifetime over state-of-the-art methods.

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