Scalable and accurate indoor positioning on mobile devices

Location-based services (LBS) are an integral part of the mobile ecosystem today, relying on the Global Positioning System (GPS) and other technologies. However, while these technologies have been highly successful at positioning outdoors, they either fail to obtain a fix or do not provide the necessary accuracy indoors. In this paper, we will describe a low-cost high-accuracy indoor positioning system that can run on mobile devices. The system has high-accuracy because it combines several sources of information, thus improving accuracy over using any one of them alone. The cost is low because the sources of information used by the system such as WiFi measurements, inertial sensor data and building maps are readily available for use on a mobile device.