提出了一种基于最小定位误差限的Wi-Fi指纹定位接入点位置优化方法.利用费歇尔信息矩阵的特性,分析了定位误差与不同信号强度分布的数学关系.首先,根据信号强度分布特性的不同,将定位目标区域划分为若干子区域;然后,推导出定位目标区域所对应的平均定位误差限;最后,利用模拟退火算法搜索最优接入点位置使得平均定位误差限达到最小.仿真结果表明,此方法可以有效提高Wi-Fi位置指纹定位法的精度.
A new access point placement optimization approach based on lowest positioning error bound in Wi-Fi fingerprint based localization was proposed. Analysis towards the theoretical relationship between positioning error and various signal distributions by using Fisher information matrix was presented. The target environment was divided into several subareas based on signal distributions. And then,the average error bound corresponding to the target environment was derived out. Thirdly,the heuristic simulated annealing algorithm towards the lowest average error bound to optimize access point locations was adopted.Simulation demonstrates that the proposed access point placement optimization approach effectively improves the precision of Wi-Fi fingerprint based localization.