摘要: | 在戰場中,無線感測網路能夠協助偵測目標物以及收集資料。然 而,當目標物及資料收集者都具有移動能力時,對於此感測網路的設 計及建置是頗具挑戰的。 目前有不少的研究報告都著重於討論多個移動的資料收集者,這 些研究中所使用的協定都需要知道資料收集者的位置及使用過多的廣 播訊息,加速了感測節點能量的消耗。為了解決此類型的問題,我們 提出了一個架構,稱為 Dynamic Overlay Construction (DOC),目的 在於收集無線感測網路中的資料。 在這個架構當中,我們擷取了網格狀網路及樹狀網路的優點,讓 資料的傳遞更有效率。再者,這兩個機制能夠作為調整整個網路的負 載平衡。網格狀網路能夠讓資料的傳遞任務能夠更加平衡;而樹狀網 路則依據網格狀網路所調整的網格大小,進而平衡每一個網格內的傳 輸負載。再加上將實現合併查詢的資料,減少每一個查詢的回應時間 以及網路使用量。 從模擬的結果中,了解到 DOC 這個架構對於解決感測網路中面 臨多個移動的收集者進行資料的收集任務所造成的問題是個不錯的架 構,而對於多個移動的目標物的資料收集而言,此架構是相當良好的。; In battlefields, the wireless sensor network can be used to detect targets and to collect data. However, the mobility of targets and sinks creates challenges for the design and implementation of the system. While there are research proposals capable of handling multiple mobile sinks, these protocols either assume the knowledge of locations of sinks or create too many flooding messages, leading to a fast battery drain. To deal with this issue, we propose a framework, called Dynamic Overlay Construction (DOC), for data collection in wireless sensor net- works. In our framework, we take the structure advantages of both grid and tree to route queries and to deliver data efficiently. In addition, two mechanisms are introduced to balance the load in the network. The first one helps to distribute the tasks more evenly; and the second one adjusts the size of grids to balance the traffic load in each grid. Lastly, an improved query aggregation is proposed to reduce the query response time and the traffic associated with each query. The simulation results show that DOC outperforms the better known data collection solutions for wireless sensor networks with multiple mo- bile sinks but the best known data collection solutions with multiple mobile targets. |