Method of locating a mobile by a management center and system of location for the implementation of the process

摘要

The method utilises mobile units (10) operating to transmit location data to the control centre at predetermined instants in time. The mobile unit and the control centre determine a tolerance zone. The mobile unit determines its position at the appointed instant in time, and if it is within the tolerance zone transmits a signal to the control centre to confirm it is within the zone expected at that instant in time. If the mobile unit is outside the tolerance zone, but is on the expected route, the mobile unit computes its distance from the expected position and transmits this to the central control station.