因為無線感知網路是由數量眾多且能量受限的感知節點所以組成,有效的能量節約機制就成為了主要探討重點。把感知節點分配到不同的叢集可以有效地使網路的使用時間延長,且利用合作式通訊更可以提升整體網路效能。然而由於不當的叢集領袖位置和合作式中繼節點的挑選機制,即使其他的節點保有充沛的能量,部分感知節點的能量快速耗盡仍然造成了網路壽命的減短。
基於 LEACH 協定,我們提出了一個能量公平性的中繼節點挑選方法來
延長整體網路使用壽命。我們提出的方法和之前的研究有些微的不同,我們提出的中繼節點挑選方法把剩餘能量和通道情況納入考量,並且從別的叢集成員挑選出來而非挑選其他的叢集首領為中繼點。藉由模擬結果我們可以在網路效能和能量使用的公平性上得到更好的成果,最重要的是我們提出的方法比起先前的研究更為有效的提升了整體網路的使用壽命。

Since wireless sensor network consists of numerous energy-constrained sensor nodes, efficient energy consumption mechanism is the key to its success. Deviding sensor nodes
into clusters is an efficient manner to enhance the network lifetime. And cooperative communication can enhance the overall network performance significantly. However,
owing to improper cluster heads’ (CHs) positions and relay selection algorithms, some nodes could exhaust energy quickly and reduce network lifetime even if there is still
much residual energy in other member nodes.
Based on the low-energy adaptive clustering hierarchy model, we propose a fair energy relay allocation (FERAL) method to prolong the lifetime of the wireless sensor network. Different from previous works, the proposed FERAL method takes theresidual energy and channel condition into consideration to select a member node in the other cluster rather than the CH as the relay nodes. Via simulation results, the superior performance in network efficiency and fairness of energy consumption can be proved. Most importantly, the proposed FERAL algorithm also outperforms the previous works in terms of the network lifetime.

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