在通訊越來越發達的時代，網路已經成為人們生活中的一個重要的部分，隨著通訊的發達及多樣化，除了舊有的網路及電話之外，漸漸發展出無線通訊的應用與技術，無線感測網路便是其中一項，然而無線感測網路中的感測器皆由電池來供應電源，為了可以延長各感測節點存活時間以便收集更多資訊，無線感測網路中電量消耗也就成為一個非常重要的研究議題。
在這篇論文中，我們利用叢集(Cluster)與感測節點擁有多個發射功率(multi power-level)兩個觀念，提出一個用於無線感測網路的通訊協定:PADCP(Power-Aware Dynamic Clustering Protocol for Wireless Sensor Network)，藉由每一個單一感測節點擁有五個不同的發射功率：Level-1 (5m)、Level-2 (18m)、Level-3 (50m)、Level-4 (68m)、Level-5 (120m)，可以依照節點疏密度形成不同大小的叢集(Cluster)。依照節點的剩餘電量、移動速度以及叢集中傳送資料所耗費的平均電量來挑選出適當的叢集閘道(Cluster-head)。各叢集閘道之間也會依照距離的不同而有不同的傳輸功率，而非叢集閘道之節點可依照自己與叢集閘道的距離選擇最小的傳輸功率。由最後的模擬實驗中，PADCP在能源的管理方面確實比其他協定優秀，藉由降低能源的消耗，進而延長無線感測網路的存活時間。而PADCP除了能源的管理之外也注重網路傳輸的效能，在節省能源的同時仍然可以使封包傳遞的成功率維持一定的水準。
關鍵字：無線感測網路、叢集、發射功率、叢集閘道

The energy consumption is the most important issue in the wireless sensor network. In order to extend the lifetime of the wireless sensor network, clustering technique is considered as an effective way to achieve the power conservation, network scalability and load balance. In this paper, we present PADCP (Power-Aware Dynamic Cluster Protocol) which is low energy clustering network architecture to increase the network lifetime and to improve the performance of transceiver by adding several adaptive schemes: dynamic cluster range, dynamic transmission power, and cluster-heads re-election. Besides, our PADCP also improves the load balance when the sensor nodes are non-uniform dispersion. In addition, the mobility of the sensors is also taken into consideration in this paper. The experimental result proves that our proposed method is effective in saving power and load balance.
Keyword:Wireless sensor network, Clustering, Lifetime

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