针对Quasi—UDG模型下无线传感器网络随机部署的拓扑特征,提出了一种非测距基于权重的定位算法EWLS(Enhanced Weighted Least Square).首先,设计出一种节点跳数和距离关系估计的方法,然后依据跳数值与距离关系的概率表达式,给出EWLS定位算法中节点测量距离信息的权重.仿真实验表明,在不同的锚节点密度、Quasi-UDG模型因子和平均邻居节点数的参数下,EWLS算法定位误差较小,同最小均方误差相比,有效地提高了节点定位的精度.
The quasi unit disk graph model of wireless sensor networks is studied in this paper and a new range-free localization method based on the weight is proposed for a scenario that sensor nodes are randomly and independently distributed in a bounded area. Firstly, we give out the relationship between hop counts and distance estimation. Then, based on the relationship expression, we design a new enhanced weighted least square (EWLS) method for localization, and give out the weight for each distance measurement. Simulation results show that. the EWLS performs better than the least square method with less positioning error under different anchor fractions, the factor of Qusai-UDG and the average local neighborhood.