Location based services for next generation wireless mobile networks

We study how wireless network can support location based services (LBS) a to mobile users. WE assume that each mobile is capable of self-geolocation using GPS and indoor geolocation [K. Pahlavan et al., Feb 2002]. The wireless network collects the geolocation information from mobiles and provides this information to application service so that the services can be custom-tailored for each mobile user. The main challenge in wireless network is to keep track of geolocation of mobile users so that the application service can maintain the quality of the service (QoS). In general, the quality of service depends on how often mobile terminals update their geolocation. Since geolocation update requires battery power and radio resource, optimizing the geolocation update frequency is critical. In this paper, we present geolocation update schemes that minimize the update frequency while satisfying the QoS of application service. For case study, we consider location based traffic report service (LBS-TR) and location based navigation service (LBS-NS). In LBS-TR, mobile users who are about to enter heavily jammed highways are informed in a timely manner so that the mobile users can avoid traffic congestion. In LBS-NS, mobile users are provided with navigation instructions that are custom-tailored to the geolocation of the users. The granularity of navigation instruction changes as the user moves from highway to local street and from local street into building complex.