复杂环境下的WIFI室内定位算法研究  

Research on WIFI indoor positioning algorithm in complex environment

作　　者：王琦 席志红[1] WANG Qi;XI Zhi-hong(Key Laboratory of Advanced Ship Communication and Information Technology,Ministry of Industry and Information Technology,School of Information and Communication Engineering,Harbin Engineering University,Harbin 150001,China)

机构地区：[1]哈尔滨工程大学信息与通信工程学院先进船舶通信与信息技术工业和信息化部重点实验室,哈尔滨150001

出　　处：《哈尔滨商业大学学报（自然科学版）》2022年第3期275-284,共10页Journal of Harbin University of Commerce：Natural Sciences Edition

基　　金：国家自然科学基金(No.60875025)。

摘　　要：室内定位环境存在各类的因素干扰(教室内人员流动、转角处墙体、多径干扰等),这些因素均会对于WIFI信号强度RSSI造成干扰,最终导致在复杂空间内的NLOS定位误差.对于现有扩展卡尔曼滤波技术进行改进,将实际观测值与预测值作差.同时设置阈值与相应的差值进行比较,以判定定位环境是否为视距/非视距并改进扩展卡尔曼滤波迭代过程.同时对于为了防止判定的不准确,加入路径损耗模型实现对NLOS误差的粗略估计,加入扩展卡尔曼的距离滤波模型做进一步估计,进而以此估计值对定位结果进行改正.利用改进后的扩展卡尔曼滤波算法消除非视距误差和噪声对定位的影响,实现了更准确的室内定位.实验表明,基于自适应卡尔曼滤波的定位方法具有较高的精度.For the indoor positioning environment, there are various types of factor interference: the flow of people in the classroom, the wall at the corner, multi-path interference and other factors, which will cause interference to the WIFI signal strength RSSI, and eventually lead to the NLOS positioning error in the complex space. Therefore, this paper improved the existing extended Kalman filtering technology to make the actual observations different from the measured values. Also set the threshold to compare with the corresponding difference to determine whether the positioning environment was sight/non-line of sight and to improve the extended Kalman filter iteration process. At the same time, in order to prevent the inaccuracy of the judgment, a path loss model was added to achieve a rough estimate of the NLOS error, and the extended Kalman distance filtering model is added to further estimate, and the positioning result was corrected by this estimate. Improved extended Kalman filtering algorithm eliminates the effects of non-line-of-sight errors and noise on positioning, enabling more accurate indoor positioning. Experiments showed that the positioning method based on adaptive Kalman filter has high accuracy.

关 键 词：室内定位 WIFI信号 非视距 扩展卡尔曼滤波 阈值 定位精度 

分 类 号：TN911[电子电信—通信与信息系统]