在無線感測器網路中，針對特定區域利用詢問執行來收集感測器所感測到的資料，或是感測器所偵測到的異常的事件是一件相當重要的功能。然而，部署在感測器網路中的感測器擁有相當有限的電量。因此，如何去找到最少的並可互相連結的感測器節點來涵蓋整個詢問區域是一件相當重要的議題。在本論文中提出一個有效的分散式的協定來尋找部分互相連結的感測器節點來涵蓋詢問區域。在感測器網路中，每一個感測器節點根據自己的優先權值來決定是否要負責偵測詢問區域。一個感測器節點的優先權值主要是由它的剩餘電量或是它在詢問區域內的感測區域大小來決定。我們提出來的協定能夠有效的建立起只包含詢問區域裡負責感測詢問區域的感測器節點並且使他們能相互連結且能快速的回應詢問請求。模擬結果顯示我們提出的協定比其它現存的協定還來的有效率並且花費較少的通訊成本。

In the wireless sensor networks, query execution over a specific geographical region is an essential function for collecting sensed data or detecting unusual event. However, sensor nodes deployed in the sensor networks have limited battery power. Hence, how to find a minimum number of connected sensor nodes that are sufficient to cover the queried region is an important issue in the sensor networks. This paper proposes an efficient distributed protocol to find a subset of connected sensor nodes to cover the queried region. Each sensor node in the sensor network determines whether to sense the queried region according to its priority value, which is determined by the remaining power or sensing area within the queried region. The proposed protocol can efficiently construct a subset of connected sensing nodes and fast response the query request in the sensed region. Simulation results show that the proposed protocol is more efficient and consumes less communication overhead than other existing protocol.

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