Multiple cellular telephones, each having a unique ESN, share the same cellular telephone number (MIN). Data records at the MSC are modified to reflect the parent and extension cellular telephones configuration. Incoming calls are delivered to all telephones sharing a MIN simultaneously, sequentially,...http://www.google.fr/patents/US6393275?utm_source=gb-gplus-shareBrevet US6393275 - Cellular extension service using single line and multiple cellular telephone sets
Cellular extension service using single line and multiple cellular telephone ...
