基于RSSI的无线传感器网络节点自身定位算法

A RSSI-Based Self-Localization Algorithm for Wireless Sensor Networks

节点自身定位是无线传感器网络的基础性问题之一.提出了一种基于接收信号强度指示(RSSI)的节点自身定位算法.该算法利用RSSI值估算网络中所有可通信节点间距离的相对大小,得到网络中各节点位置之间的几何约束关系,并以此为约束条件,以锚节点质心和未知节点质心之间的距离最小为目标,将定位问题转化为非线性最优化问题.实验结果显示,当锚节点分布在网络边缘时,该算法可以达到较好的定位效果.

Self-localization is one of the basic problems in wireless sensor networks. Presented in this paper is a RSSI-based self-localization algorithm. First, the received signal strength indications (RSSI) are used to estimate the relative distances of the communicatable paired nodes. Then these relative distances are modeled as a set of square constraints. And the distance between the centroid of anchors and that of the unknown nodes is regarded as the minimize object. Finally, estimations of the unknown node positions are obtained by the global solution of a non-linear optimization problem with these constraints. Experiment results show that the algorithm performs well in localization accuracy when with anchors at the fringe of the networks.