中文摘要：

在基于无线局域网定位问题中，采样点间距、接入点的个数以及环境的干扰是影响定位平均误差的重要因素，但是对于这些参数的选取目前还没有系统的指导，主要根据经验来确定。提出了一个表示定位平均误差的数学模型，形式化地全面概括了定位问题中的关键因素。基于该模型，分析了采样点间距，接入点个数和环境与定位平均误差之间的关系。仿真结果表明采样点间距取1米即可满足定位的要求，选择多于3个接入点的定位对于弥补环境干扰，减小定位误差有显著的作用。

英文摘要：

In WLAN-based location estimation problem, the grid spacing, the number of access points, and the interference of environment are key factors for average error of location estimation, however, there isn＇t a general strategy on how to determine these parameters. They are mostly determined by experience. A mathematical model of average error of localization was proposed, which formally described the key factors for errors in WLAN-based location estimation. Based on the model, the relationship between the average error and these factors was analyzed. Simulation results show that it satisfies to localize users with a grid spacing of one meter and using more than three access points can remarkably reduce the average error of location estimation and alleviate the environmental interference.