关键词: 无线传感器网络, 层次型网络, 密度分布, 节点布置

Abstract: For large-scale layered wireless sensor networks，the node is closer to the sink，the amount of data need to be transmitted is larger and the energy is consumed faster.So how to distribute the nods is important for the lifetime of the whole networks.This paper investigates energy consumption and density distribution in layered wireless sensor networks and a scheme of deploying sensor nodes is proposed.Compared with the scheme of deploying sensor nodes uniformly，the scheme proposed in this paper can effectively prolong the lifetime of the networks.

Key words: wireless sensor networks, layered networks, density distribution, node deploying scheme