改进的RSSI测距和定位算法

分析了RSSI(received signal strength indicator)测距的原理及环境对RSSI的影响。论述了高斯模型校正算法,该算法中因含有与环境相关的路径散逸指数而产生较大测距误差。针对这一问题,提出了基于锚节点的高斯校正算法,该算法以锚节点对之间的已知距离和测量的RSSI值为参考,对由被测RSSI值得到的距离进行校正,消除了路径散逸指数,并用网络连通信息和RSSI联合定位。仿真结果证明:采用锚节点的高斯校正算法进行定位不受环境影响,不同环境下最大定位波动为0.11%,定位误差显著减小,可应用到实际的无线传感器网络的定位系统中。

Improved algorithm of ranging and locating based on RSSI

This paper analyzed he theory of distance measurement based on RSSI and the influence of environment on RSSI. It discussed the improved Gauss model algorithm, and introduced larger ranging error due to environmental path dispersion index . In order to solve this problem, it proposed a improved Gauss algorithm based on anchor nodes. In this algorithm, it used the known distance and measured RSSI between anchornodes to correct the distance by being measured RSSI value, and eliminated path dispersion index. then it used both network connectivity information and RSSI to locate. Simulation result shows that location error of anchor node-gauss algorithm is independ on environment, the most fluctuation of localization is 0. 11% in different enviroment, and location errors are also decreased significantly. So this algorithm can be used in real location system for wireless sensor networks.