Estimation of Mobile Trajectory in a Wireless Network: A Basis for User´s Mobility Profiling for Mobile Trajectoy Based Services

A new trend of mobile wireless services based on trajectory of a mobile phone and hence that of a mobile user, called Mobile Trajectory Based Services (MTBS) is emerging. To provision MTBS, a mobile operator needs to determine the trajectories of a mobile user over a period of time (a week for example) and then save them as mobility profile. There are two major challenges in determining the trajectory of a mobile user: 1) Location estimation error 2) Location estimation polling frequency. We propose an adaptive polling method such that the polling is not frequent to overburden the air resources unnecessarily and it is not sparse that leads to an ambiguous and erroneous mobility profile. The polling method includes a new map matching scheme using GIS (Geographical Information System) map. The scheme is based on previous location, map topology and travel time from one intersection to other. So, from erroneous and moderately polled location points with time stamps, we form a spatiotemporal trajectory for a mobile user. A set of such trajectories for all days of the week would form a mobility profile, on which plethora of MTBS could be provisioned.