无线传感器网络中基于RSSI的质心定位算法研究

摘要

无线传感器网络中，由于传统质心算法普遍存在信标节点分布不均与中心化问题，导致定位误差相对较大。针对这些问题，提出了基于RSSI的改进算法。在APIT的基础上，改进算法依靠未知节点接收到不同信标节点的RSSI数值，判断其周围是否存在最佳三角形，若存在则利用最佳三角形进行定位；若不存在则选出一个距其较近的三角形，利用移动信标节点的办法来缩小此三角形的范围进行定位。Matlab平台仿真结果表明，与传统质心算法相比，改进算法减少了定位误差，节点定位精度有所提高。%In wireless sensor network,due to the widespread problems of beacons nodes' uneven distribution and centraliza⁃tion,traditional centroid algorithm has relatively large positioning error. In order to solve these problems,an improved algorithm based on RSSI is proposed. On the basis of APIT,the improved algorithm uses the received signal strength from different bea⁃con nodes to determine whether the surrounding of a unknown node exists the best triangle. If does,the improved algorithm would use the best triangle to locate. If not,the improved algorithm would select a triangle which is closer to the unknown node and use the method of moving beacon node to narrow range of the triangle to locate. The results of Matlab simulation shows that, compared with the traditional centroid algorithm,the improved algorithm can reduce the positioning error and improve the posi⁃tioning accuracy of nodes.