基于锚圆交点加权质心的无线传感器网络定位算法

Weighted centroid localization algorithm based on intersection of anchor circle for wireless sensor network

针对无线传感器网络节点能量有限,基于距离的定位算法有时并不适用的问题,在研究了未知节点与其无线射程范围内的3个锚节点之间的通信约束和几何关系的基础上,提出了一种基于锚圆交点加权质心的定位算法。该定位算法仅基于网络连通性而不需要测量距离,算法计算量小,节点通信开销小。仿真结果表明,当在100m×100m的区域范围内随机部署100个传感器节点,通信半径为30m、锚节点密度为16%时,相对定位误差为22.7%。

Range-based localization schemes are sometimes not feasible due to hardware cost and resource restriction of sensor nodes.The geometric relationships and communication constraints among unknown node and anchor nodes are studied.A weighted centroid localization algorithm based on intersection of anchor circle is proposed.If there are anchor nodes within the communication range of an unknown node,the unknown node must be inside the triangle constituted by the intersection of the anchor circles.It is assumed that the location estimation of the unknown node is the triangle centroid.To increase the positioning accuracy an improved scheme is proposed.It uses RSSI as weight function and takes the weighted centroid of the triangle as the location estimation of the unknown node.This range-free algorithm is based exclusively on connectivity of sensor networks.The communication and computational loads are small.Simulation results show that the relative localization error is 22.7% when 100 sensor nodes are randomly deployed in 100 m×100 m scenario with 30 m communication range,and the anchor density is 16%.