無線感測網路(Wireless Sensor Network)的存活期取決於感測器的電池電量，由於感測器通常以隨機方式佈建於網路中，且其運作一段時間後剩餘電量可能不一致，若利用傳統的Voronoi Diagram來劃分每個感測器的感測區，則電量小的感測器會為了與鄰居平均分攤感測範圍而很快地耗損其所有的電量。本論文所考慮的感測器其感測範圍為可調式，電量之消耗與感測半徑成平方比例，在這樣的環境下，根據各個感測器的電量不同，發展一具有電量平衡的Weighted Voronoi Diagram，並據此劃分感測器應有的有效感測區域，使電量較大的感測器可以擁有較大的感測半徑，藉以達到電量平衡及全區覆蓋的目的。除了討論1-Coverage的技術外，本論文亦擬將可調感測範圍的技術延伸達到k-Coverage的覆蓋目標。模擬結果顯示，本演算法在1-Coverage之網路存活期的效能上，有明顯的改善，延伸在k-Coverage的技術也有極佳的效能。 Coverage is one of the most important issues in wireless sensor networks (WSNs). Given a randomly deployed WSN, how to achieve the both purposes of maintaining full coverage and maximizing network lifetime has been received much attention in recent years. This paper considers the area coverage problem for a WSN where each sensor has variable sensing radius. A Weighted Voronoi Diagram (WVD) is proposed as a tool for determining the sensing region of each sensor node according the remaining energy in a distributed manner. To maximize the network lifetime, techniques for balancing energy consumption of sensors are further proposed. Simulation results reveal that the proposed energy-balanced coverage mechanism outperforms the existing works in terms of network lifetime.
