室内定位信号强度—距离关系模型构建与分析

The Construction and Analysis of the Indoor Positioning Received Signal Strength Indication-Distance Relationship Model

室内定位的关键技术之一在于室内距离的精确确定。基于WiFi信号强度确定室内距离的技术主要是利用WiFi信号在传播路径中发生衰减的原理实现位置推算。根据室内WiFi信号强度随距离变化这一物理特性,基于对数-距离模型,通过对实测信号强度(RSSI)与距离进行拟合,构建了基于信号强度—距离的室内定位多项式模型,并对其进行精度评定,实现了模型的优化,提高了信号强度转化距离的精确度。结果表明,采用对数-距离模型和对数拟合模型计算距离与真实距离的平均偏差为0.73m和0.56m,新设计的信号强度-距离多项式模型解算结果平均偏差为0.26m,优于之前两种模型,可为相关研究提供参考。

The principle of indoor distance determination using WiFi signal strength indication is based on the reduction of WiFi signal strength in the course of transmission.According to this physical characteristic,based on the logarithmic-distance model,an indoor distance polynomial model has established based on the received signal strength indication（RSSI）and the actual distance fitting analysis.Furthermore,the precision assessment has been carried on,and the optimization of the mode has been realized,with an improvement of the accuracy of indoor distance determination.Results show that,the average deviations between the distances the logarithmic-distance model and logarithm fitting model calculated and the actual distance are 0.73 mand 0.56 m,respectively.The average deviation between the distance calculated by the polynomial model based on signal strength-distance and the actual distance is 0.26 m,which is much better than the results of the former two models.The results can provide reference for similar research.