Drawbacks of known methods of location determination are that the location can be determined only when the mobile station is setting up a call and during the call. The invention utilises that characteristic feature of mobile telephone systems that the location of the terminal is always known to the system...http://www.google.fr/patents/US6636742?utm_source=gb-gplus-shareBrevet US6636742 - Tracking of mobile terminal equipment in a mobile communications system
Tracking of mobile terminal equipment in a mobile communications system
