一种基于先验信息的WiFi室内定位方法

多种室内定位技术中,基于WiFi的定位在基于位置的服务(location based service,LBS)中有着巨大的应用潜力。提出一种新的室内WiFi定位方法,结合分级定位结构,能够有效利用人员行走模式先验信息。该方法在预备粗定位阶段通过上一时刻的位置推断可能区域,通过信号指纹检测器判断可能区域是否正确,通过再次粗定位阶段重新推算可能区域。在精定位阶段,该方法通过最大后验概率密度方法得到位置估计。利用开源数据集进行实验,证明了所提方法相比传统的3种方法(无先验的最大后验、先验kNN和无先验kNN方法),定位精度分别提高了3%、5%和7%。

WiFi based indoor positioning method using prior information

Among many indoor positioning methods, WiFi based indoor positioning has great potential use in location based Service(LBS) applications. A new WiFi based positioning method is proposed in this paper, which adopts the prior information of user walkingpatterns. The method can also effectively adopt the traditional hierarchical positioning structure. In the pre-coarse positioning phase, themethod can adopt the position estimation from the previous time to define the potential areas. In the signal fingerprint test phase, thepotential areas can be tested to know whether it is right or wrong. If wrong, the second coarse positioning phase is carried out to re-definethe potential areas. Then in the fine positioning phase, the maximum posterior (MAP) based method is adopted to estimate the userposition. The proposed method is tested using an open access dataset, the results have shown that the proposed method can effectivelyadopt prior information and can increase positioning accuracy by 3%, 5% and 7% over the traditional methods ( no prior&MAP,prior&kNN and no prior&kNN) respectively.