基于前进跳距期望的异构WSNs非测距定位算法

Expected Hop Progress-Based Range-Free Localization Algorithm in Heterogeneous WSNs

无线传感网络(WSNs,wireless sensor networks)中传感节点的传输范围直接决定节点的通信区域,对定位精度有直接的影响。为此,针对异构WSNs,提出基于前进跳距期望的非测距定位算法。首先,分析传统推导前进跳距期望(EHP,expected lop progress)方法的不足,并证实了EHP值只依赖锚节点的传输范围是不准确的;然后,采用新方法推导了EHP,并结合泰勒级数展开以及加权最小二乘算法估计未知传感节点位置;最后,以降低误差为目的,迭代修正未知传感节点位置的估计值,从而提高定位精度。仿真结果表明,与传统的非测距定位算法相比,提出的算法的定位精度得到有效提升。

In wireless sensor networks（WSNs）,the transmission capability determines directly node communication area,so it effects on localization accuracy.Therefore,for heterogeneous WSNs,the expected hop progress-based range-free localization algorithm is proposed.Firstly,shortage of the traditional method of deducing the EHP（expected hop progress） is analyzed,and it is shown that EHP depends only anchor node transmission capability is not accurate.Then,EHP is deduced by new method,and the position of unknown sensor nodes is estimated by Taylor series expansion and weighted least squares algorithm.Finally,with the purpose of decreasing the errors,the estimated locations of unknown sensor nodes are iteratively corrected.Simulation results show that the accuracy of proposed algorithm is better than the most representative range-free localization algorithms.