A location-based service includes detecting the relative motion of an on-site resource, detecting the absolute position of the on-site resource, and tracking the position of the on-site resource. The position is tracked by deriving a deduced position based on the detected relative motion and adjusting...http://www.google.fr/patents/US7996281?utm_source=gb-gplus-shareBrevet US7996281 - Tiered on-demand location-based tracking service and infrastructure
Tiered on-demand location-based tracking service and infrastructure
