Arrangement in a system including mobile units.

摘要

A system comprises mobile units and virtual beacons/radio beacons (VB). An arrangement determines whether a mobile unit passes an affected beacon. A unit (BLT) extracts a first position information produced by the system for the current virtual beacon. Elements are arranged to determine if the said passage exists or not in dependence on a comparison function with the second position information relating to the position of the mobile and extracted from an external position determining system (EPD). <IMAGE>