稀疏节点下APIT算法的一种改进

APIT定位算法对硬件要求不高,定位较精确,易于实现,被广泛应用于无线传感器网络定位系统,但存在因锚节点稀疏而带来的定位精度低的问题;对APIT算法进行了深入分析,通过引进新的算法(设置一个计数器比较判内判外的次数,然后比较其权重提高判别的准确率;或者利用计数器计算跳数最后用三边测量法估算位置)对其在节点稀疏环境下边缘地区无法定位的问题进行改进,并从节点比例方面比较了两种算法的定位精度和覆盖范围;在1000m*1000m范围内设置160个未知节点与80个锚节点并逐次改变锚节点个数进行仿真定位;结果表明,在锚节点稀疏情况下,改进的APIT算法定位精度和覆盖率均远高于传统APIT算法。

An Improved APIT Algorithm in Sparse Node Environment

Range-free localization algorithm in APIT has Low hardware requirements and has a high accuracy,which is very easy to implement and is widely used in wireless sensor network positioning systems,but there is a low accuracy when anchor is sparse distribution.This paper analyzes APIT algorithm,and improves its edge node cannot be located in sparse node environment by a new algorithm(to set within a sub-counter compared the number of outside contractors and then compare their weight to improve the accuracy of identification,or to count jumped several and then estimate location with Trilateral measure).The performances of these two algorithms included positioning accuracy and coverage are compared in terms of different anchor ratios.We have set within the 160 unknown nodes and 80 anchor nodes In 1000m * 1000m areas and change the number of anchor nodes successively to simulate its positioning.Simulation experimental results show that both accuracy and coverage of improved APIT algorithm is much higher than traditional APIT algorithm.