中图分类号：TN92 文献标志码：A DOI: 10.16157/j.issn.0258-7998.233941 中文引用格式： 唐杰，黄铭，林建喜，等. 基于WiFi信号的室内外联合定位技术研究[J]. 电子技术应用，2024，50(1)：113-119. 英文引用格式： Tang Jie，Huang Ming，Lin Jianxi，et al. Research on indoor and outdoor joint positioning technology based on WiFi signal[J]. Application of Electronic Technique，2024，50(1)：113-119.
Research on indoor and outdoor joint positioning technology based on WiFi signal
1.School of Information Science and Engineering， Yunnan University， Kunming 650091， China； 2.Radio Monitoring Center of Yunnan Province， Kunming 650228， China
Abstract： The current indoor and outdoor joint positioning technology based on GPS and WiFi achieves high positioning accuracy. However, this type of method needs to process signals of two different scenarios in the transition area, and there are problems such as difficulty in smooth switching between areas, and lack of effective data association. In response to the above problems, this paper associates the physical space location information with WiFi information to establish an indoor and outdoor joint positioning map model based on WiFi signals, and uses the Jaccard similarity algorithm for indoor and outdoor judgment and one-time positioning. In order to increase the positioning accuracy of WiFi, this paper uses cubic spline interpolation to expand the WiFi fingerprint library, and uses the weighted K-nearest neighbor algorithm for secondary precise positioning.
Key words : WiFi positioning；graph model；similarity；secondary positioning；visualization
引言
基于WiFi信号定位主要应用于室内场景，最近已有许多学者开始研究基于WiFi基础设施的无GPS室外定位服务[1]。与超宽带定位技术、蓝牙定位技术和惯性导航技术等比较，基于WiFi位置指纹定位技术无需额外添加其他设备，且部署简单、成本较低、定位范围广、精度较高[2]。因此，基于WiFi技术实现定位是一个较好的选择。当前解决室内外联合定位问题技术的大多是卫星定位系统与室内定位组合技术，而且主要是针对在室内外过渡区域平滑切换定位方法问题，文献[3]提出了坐标标定法，使得室内外坐标达到一致。在过渡区域中使用越区切换方法，实现基于北斗和超宽带的室内外联合高精度定位。城市环境或园区内卫星信号较差，但是已经大量部署WiFi网络，文献[4]设计了一种基于WiFi信号的室外人员定位系统，通过动态选取k个锚节点建立定位模型，并且改进接收信号强度指示(Received Signal Strength Indicator, RSSI)测距方法以提高定位精度。文献[5]设计了基于WiFi信号的园区定位与导航系统,提供了园区内高精度定位服务。针对定位延迟问题，文献[6]提出了分级定位方案，首先通过汉明距离确定多个子区域，再在子区域内通过k近邻算法进行精定位。基于位置指纹的定位精度与其采集的指纹密度有关，通过空间插值法对其他位置的定位信息进行扩充可以提高定位精度，而且能够降低前期数据采集工作量[7]。最近有研究者从室内位置信息与定位信息融合角度出发进行定位研究[8-9]，提出了基于知识图谱WiFi定位方法，侧重于有效整合室内WiFi数据和空间环境特征信息。
