Orientation-based Wi-Fi positioning on the google Nexus One

While localization systems for indoor areas using the existing wireless local area network (WLAN) infrastructure have recently been proposed, wireless LAN localization approaches suffer from a number of significant drawbacks. To begin with, there is inaccurate position tracking due to the orientation of the mobile device and signal fluctuation. In this paper, we apply an orientation filter and a Newton Trust Region (TR) algorithm to eliminate the noisy location estimation. We implement the localization algorithm on the Nexus One which is a Wi-Fi enabled device with a digital compass. The average error distance is only 1.82m. We achieve 90% precision within 2.45m. The proposed method leads to substantially more accurate and robust localization system.