06011973 is referenced by 301 patents and cites 18 patents.

The present invention provides a method and apparatus for restricting operation of a cellular telephone to well delineated geographical areas. The cellular telephone is equipped with a location device for ascertaining the current geographical location of the cellular telephone. The ascertained geographical location is compared with information pertaining to the allowability of operation of cellular telephones in various geographical locations. A determination is made as to whether the cellular telephone is allowed to operate in its current geographical location. The cellular telephone accordingly enables or disables transmitting by the transceiver of the cellular telephone.

Title
Method and apparatus for restricting operation of cellular telephones to well delineated geographical areas
Application Number
8/759997
Publication Number
6011973
Application Date
December 5, 1996
Publication Date
January 4, 2000
Inventor
Vladimir Alperovich
Dallas
TX, US
Eric Valentine
Plano
TX, US
Agent
Jenkens & Gilchrist P C
Assignee
Ericsson
NC, US
IPC
H04Q 7/00
View Original Source