Wi-Fi/MARG/GPS integrated system for seamless mobile positioning

Providing a seamless, ubiquitous and reliable positioning system based on smartphones plays a critical role in increasing pervasive sensing environments and location-based services (LBS). Although the Global Positioning System (GPS) has been widely used in outdoor environments, indoor/outdoor seamless positioning is still a challenge because of the unavailability of GPS in indoor environment. To solve this problem, an advanced integration of Wi-Fi, MARG (magnetic, angular rate, and gravity sensors) and GPS is presented in this paper. In order to merge there heterogenous but complementary technologies on smarphones, an adaptive integration structure based on Kalman Filter (KF) and Particle Filter (PF) is proposed. Besides, experiments have been carried out in real indoor/outdoor environment to evaluate performance of proposed system. Experimental results indicate a remarkable performance improvement by using the proposed integrated system.