Harnessing Wireless LAN Communication for Scalable Indoor Localization and Tracking

Localization of people is an integral aspect of mobile computing research that has been investigated primarily on the basis of radio or sound sensor technologies such as Bluetooth, WLAN or ultrasound. Due to the physical behavior of these carrier technologies in different environments, a principal distinction between outdoor and indoor localization has evolved. As an outstanding example of applied localization technologies, the Global Positioning System demonstrates the feasibility of a client-based solution to the outdoor localization problem on a global scale. For indoor spaces on the other hand, no convincing counterpart has emerged so far. The problem of localizing people indoors is still considered a matter of intense research. Basically, two approaches exist for determining the user’s location indoors. The client-based variant assumes that sensor functionality is integrated in the mobile device of the user. The infrastructure-based solution uses sensors embedded in the environment. Recently, client-based WLAN localization has been the prevalent choice of technology for both mobile application research and the consumer market mainly because of the high availability of WLAN communication hardware.