基于RSSI的WSN二维对数搜索定位算法

RSSI-based Two-dimensional Logarithmic Search Localization Algorithm for WSN

定位技术是无线传感器网络(WSN)应用的关键技术之一。针对WSN中的定位问题,提出一种基于接收信号强度指示(RSSI)测距的二维对数分布式搜索定位算法。采用改进的RSSI测距模型测量节点之间的距离,利用质心定位算法结果作为搜索起点,设计一种基于最小加权距离误差和的目标函数,对于每个节点通过二维对数搜索的方法,搜索具有最小加权距离误差和的点作为定位位置。仿真实验比较了质心定位算法、不带权值的二维对数搜索定位算法、基于RSSI的二维对数搜索定位算法在不同条件下的定位性能,结果表明基于RSSI的二维对数搜索定位算法的定位精度远优于质心定位算法,相比不带权值的二维对数搜索定位算法约提高了0.02R。

Localization technology is one of key technologies in Wireless Sensor Network（WSN） application. Focusing on the localization problem of WSN, this paper proposes a Received Signal Strength Indicator（RSSI）-based two-dimensional logarithmic search localization algorithm. The algorithm adopts modified RSSI-based ranging model to estimate the distance of nodes, utilizes the results of centroid localization algorithm as search initial point, and employs two-dimensional logarithmic search method whose objective function is to minimize the sum of distance error with improved weighting factors to distributed realize self-localization. Experiments compare the localization performance of centroid localization algorithm, two-dimensional logarithmic search algorithm without weight, and two- dimensional logarithmic search algorithm based on RSSI. Results show that localization precise performance of proposed algorithm is much better than that of centroid algorithm, and improves 0.02R compared with two-dimensional logarithmic search algorithm without weight.