無線感測網路(Wireless Sensor Network ,WSN)的感測節點電量相當有限，因此要如何佈署這些節點並設計有效的路由演算法來延長整體的網路壽命是相當重要的研究議題。在相關研究中，LEACH路由演算法在每一回合隨機選擇叢集頭並重新建立叢集，容易造成額外的電量消耗，且無法維持最佳傳輸距離的問題。本研究參考LEACH叢集式網路的概念，提出了叢集分配演算法，它以高密度優先的方式來分配節點以形成固定叢集，以具有較多的節點來分擔叢集頭的電量消耗；接著使用高能量優先法選擇叢集頭來平均消耗叢集中感測節點的電量；再加入睡眠模式以及資料聚集的方法以節省節點的耗電量。本研究使用以上的方法來解決LEACH的電量消耗問題以延長感測節點的壽命。由於在基地台周圍的感測節點的資料接收量大，所以耗電量也相對較高，因此本研究提出使用密度比例分配法來增加基地台周圍的節點數以分擔其高資料量的負擔，而研究結果發現此方法可以有效提升整體感測網路的壽命。

The electric power of sensor nodes is limited in a wireless sensor network, and therefore how to distribute these nodes and design an efficient routing algorithm to extend the life of the whole network is a very important research topic. In the related research such as LEACH routing algorithm, clusters are formed by randomly selecting cluster heads to form clusters, which may cause unnecessary power consumption and the inability to maintain optimal transmission distance. Based on the concept of LEACH cluster-based network, this study proposed a cluster allocation algorithm, which uses the high-density first method to form fixed clusters, and then uses the high-energy-first method to choose cluster head to average out the power consumption in each sensor node; the sleeping mode and data aggregation scheme are also utilized to save the electric power to extend the life of sensor nodes. In this study, the clusters are established by finding the areas of higher node density, so there are more nodes in a cluster to share the work load of cluster head. This study uses the above methods to solve the problem of power consumption in LEACH to extend its lifetime. Since the sensor nodes around the base station need to transmit a large amount of data, they will also consume more electric power. Therefore, this study proposed the uneven density distribution method to increase in the number of nodes around the base station. The objective is to share the work load of sensor nodes when transmitting a large amount of data around the base station, and the simulation result shows that it can efficiently improve the lifetime of the overall sensor network.

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