Smartphone-based Pedestrian Localization Algorithm using Phone Camera and Location Coded Targets

With the rapid development of national economy, higher requests have been put forward on indoor and outdoor seamless PNT (positioning navigation and timing) service. Meanwhile, with the popularity of smartphones and the rapid development of MEMS (microelectromechanical system) sensors, researches on smartphone-based high-precision, high-reliability, but low-cost seamless indoor/outdoor navigation method have become the highlighted topics. On the basis of the detailed analysis of smartphone camera's capability, this paper analyzed the method of coded targets aided pedestrian navigation techniques. With digitalized BIM (building information model), this paper proposed an algorithm for fast, precisely and robustly recognizing and matching artificial targets, from which the position and orientation of camera can be deduced and helps to improve the locating performance of smartphone. Laboratory experiments have been carried out to verify the feasibility of this vision-aided method: the locating precision of the proposed algorithm can reach cm level, whose exposure time is 50us and its corresponding process time is about 33ms, which could be of great use for the seamless indoor and outdoor locating with off-the-shelf smartphone.