A short-range RF network deployed at a site larger than the coverage area of a single short-range RF transceiver includes a plurality of short-range RF transceivers deployed with overlapping coverage areas and accessible through a gateway, and accommodates terminal devices to establish communication...http://www.google.es/patents/US6954443?utm_source=gb-gplus-sharePatente US6954443 - Short range RF network with roaming terminals
