基于最小均方误差选择参考节点的RSS测距定位算法  

Mean square error choice of the reference node based RSS Ranging Localization Algorithm

作　　者：蔺莉[1] 汤震[1] 

机构地区：[1]黄淮学院信息工程学院,河南驻马店463000

出　　处：《激光杂志》2015年第4期174-178,共5页Laser Journal

基　　金：河南省科技攻关计划项目(编号:122102210430)

摘　　要：无线传感网中的多类应用均需要准确的定位算法。为了降低定位成本,减少能量消耗,常采用基于接收信号强度RSS(Received Signal Strength)测距,并建立相应的方程,再利用线性最小二乘LLS(Linear Least Squares)法求解节点的位置,将此定位算法记为RSS+LLS算法。RSS+LLS算法随机选择参考节点,这有损定位精度,同时,LLS算法并没有考虑每个测距值的误差,这些不足降低算法的定位性能。为此,提出基于RSS+LLS的优化算法,记为RSS+WLS+OPT算法。该算法先通过RSS测距,并基于最小均方误差原则选择参考节点,从而提高定位精度,同时,给每个测距值引入权重系数,采用基于协方差矩阵的加权最小二乘法WLS(Weighted Least Squares)求解节点位置,进而降低了测量误差对定位精度的影响。仿真结果表明,与RSS+LLS相比,提出的RSS+WLS+OPT算法的定位精度提高了约2米,并没有增加计算时间,降低对测距误差的敏感性。In the wireless sensor networks,location based applications require an accurate localization algorithm.To locate sensors at a low cost,the received signal strength(RSS)based linear least squares(LLS)localization is favored by many researchers,which is marked as RSS+LLS.RSS positioning does not require any additional hardware on the sensors and does not consume extra power.A low complexity solution to RSS localization is the linear least squares(LLS)method.In this paper,to improve the performance of RSS+LLS,optimal of RSS+LLS is proposed,which is marked as RSS+LLS+OPT.First,a weighted least squares(WLS)algorithm is proposed,which considerably improves the location estimation accuracy.Second,reference anchor optimization using a technique based on the minimization of the theoretical mean square error is also proposed to further improve performance of LLS and WLS algorithms.Simulation results show that the proposed RSS+LLS+OPT improve performance in terms of location estimation accuracy with about 2m and without increasing computation time,compared with RSS+LLS.

关 键 词：接收信号强度 线性最小二乘 加权最小二乘 参考节点 定位 

分 类 号：TP212.9[自动化与计算机技术—检测技术与自动化装置] TN929.5[自动化与计算机技术—控制科学与工程]