Alternatives to GPS for Localization Leveraging Smart Phones

In recent years, the proliferation of smart phones has helped the spread of Location Based Services (LBS) with multiple applications (e.g. monitoring, tracking, assisted living, targeted advertising or social networking). For instance, about 10% of all the iPhone applications employ location information and a quarter of all USA wireless phone users have already utilized LBS.

The most powerful countries in the world understand the strategic need for localization (beyond military operations) and are investing heavily in the development of satellite navigation systems (e.g. USA's GPS, Russia's GLONASS, European Union's Galileo, or China's Compass). However, all these satellite-based localization systems fail to deliver accurate information in many urban environments and buildings where the direct visibility to the satellites is lost. In fact, we work and spend most of our time in urban areas or indoors with no coverage at all from these satellite-based systems. Consequently there is a need for location information in these areas. Both industry and academia have recently developed alternative localization systems for indoor environments. Nevertheless, most of the proposed alternatives are dedicated systems requiring the deployment of extra hardware (e.g. systems based on ultrasounds, infrared or RFID technologies).

In this talk we will show that it is feasible to leverage the existing technologies and sensors (different from GPS) embedded within smart phones to obtain precise location information in those areas lacking satellite coverage. We will focus on the possibilities offered by cellular and WiFi technologies, together with accelerometry.