Abstract: In order to solve the “hot spot” problem in multi-hop routing protocol of wireless sensor networks, an Energy Optimized Uneven Clustering Routing protocol （EOUCR） is proposed after researching on EEUC. In this routing protocol, three parameters, i.e., the candidate cluster head’s residual energy, its neighbor’s average residual energy and the distance of the candidate cluster head to SINK, are considered in the cluster formation phase. Meanwhile, EOUCR partitions all nodes into clusters of unequal size, and takes energy consumption into account while calculating competitive radius. In this way, the cluster head rotation frequency can be reduced when cluster is in “hot spot”, and the network loading is balanced. Furthermore, a unique root node is introduced. This root node communicates with the SINK node solely in clustering multi-hop routing. Other cluster heads communicate with the root node through the relay node or directly. Thus, the “hot spot” problem near the SINK node can be solved effectively through EOUCR by overcoming EEUC’s  deficiency of larger and unbalanced energy consumption. Simulation results show that EOUCR can more efficiently save energy of nodes, balance the energy dissipation of all nodes, and prolong the network lifetime.

Key words: Wireless Sensor Networks（WSNs）, multi-hop routing, uneven clustering, hot spot, root node

摘要： 为解决无线传感器网络多跳路由协议的“热区”问题，基于对EEUC协议的分析，提出了一种能量优化的WSNs非均匀分簇路由协议EOUCR（Energy Optimized Uneven Clustering Routing protocol）。该协议在簇形成阶段以候选簇头的剩余能量、其邻居节点的平均剩余能量和该候选簇头与SINK节点的距离作为竞选簇头的参数，且簇头竞争半径的选取考虑了成簇能耗，在此基础上形成了不同几何尺寸的簇，可减少“热区”内簇的簇头轮换次数，均衡网络负载。EOUCR在簇间多跳路由通信中引入了唯一与SINK节点通信的根节点，其他簇头则通过中继节点或直接与根节点通信，克服了EEUC能耗大且不均衡的不足，从而有效地解决临近SINK节点的“热区”问题。仿真实验结果表明，EOUCR能够更有效地节约节点能量、均衡网络能耗、延长网络生存周期。

关键词: 无线传感器网络, 多跳路由, 非均匀分簇, 热区, 根节点