在無線感測網路 (Wireless Sensor Network)中，感測節點常以多躍代傳的方式將感測資料傳送至 Sink，導致 Sink 附近的感測節點因代傳大量的感測資料而提早耗盡電池的電量，進而縮短網路的生命期。為了解決此電量消耗不平衡的問題，本論文針對一隨機佈建的感測網路，提出一分散式二階段之演算法，以期達到電量平衡的目標。在第一階段中，本論文考量 Sensor 的剩餘電量，建構一電量平衡的資料收集樹狀拓樸，使剩餘電量較高的 Sensor 能執行較多的資料代傳工作，進而達到樹狀拓樸中同層 Sensor 間的電量平衡。在第二階段中，本論文針對 Sensor 之代傳資料量提出一可調式感測範圍的控制技術，以平衡網路拓樸中各層 Sensor 的電量消耗，以期達到剩餘電量平衡及全區覆蓋的雙重目的。最後，模擬結果顯示此電量平衡演算法在多躍資料代傳及可調式感測範圍的環境下皆能有效平衡網路中各 Sensor 之電量，並延長網路生命期。 In the Wireless Sensor Network (WSN), data collection from all sensors to the sink node is usually achieved in a multi-hop transmission manner. This leads to the energy imbalanced problem where sensors closer to the sink exhaust their energy earlier, reducing the network lifetime. This paper proposes a two-phase algorithm aiming at prolonging the network lifetime of a given WSN. The first phase constructs a tree-based topology which takes into consideration the remaining energy and transmission load of each sensor. In the constructed tree topology, sensors with higher remaining energy connect to more children such that energy balancing is achieved for all sensors in the same level of the tree. To balance the lifetime of sensors belonging to different tree levels, the second phase further adjusts the sensing range such that both full coverage and energy balance purposes can be achieved. Simulation results reveal that the proposed energy balancing algorithm outperforms existing works in terms of energy balance and network lifetime.
