Abstract: The node localization scheme of wireless sensor networks is essential to many applications，and many have been proposed for static WSN.This paper proposes a range-based algorithm PMAIL（PSO-based Mobile Anchor Incremental Localization），in which nodes are graded according to precision，and those with higher levels are chosen as reference to locate the unknown nodes incrementally.PSO algorithm is used to optimize the function of weighted errors.PMAIL does not specify any particular ranging method，and the mobile anchor could also be a sink node for data-gathering and network management.Simulations show that higher coverage is reached，and location precision increases approximately 9%.

Key words: wireless sensor networks, mobile anchor, localization, Particle Swarm Optimization（PSO）

摘要： 无线传感网节点自定位技术是许多相关应用的前提和基础，目前已提出多种定位算法，但大多用于静态无线传感网。针对使用移动锚节点定位场景提出一种基于测距的算法PMAIL（PSO-based Mobile Anchor Incremental Localization），将节点精度分级，选择高等级参考节点进行增量式定位，同时使用粒子群算法（PSO）求解加权误差方程，得到最优位置估计。算法不局限于特定测距方式，锚节点可同时支持常见的移动sink数据收集和网络管理等功能。仿真表明算法有较高的网络覆盖率，精度提高接近9%。

关键词: 无线传感器网络, 移动锚节点, 定位算法, 粒子群算法