Patent ID: 7142877

Claim:
A system for selectively restricting the radio frequency transmission of a cellular telephone within a defined restricted-communication area, comprising: a transmitter for generating a control signal at an entrance to the restricted-communication area, said transmitter having a broadcast area not being coextensive with the restricted-communication area; the cellular telephone including a subsystem for transmitting a cellular telephone audio signal on a radio-frequency carrier; a receiver subsystem within the cellular phone responsive to said control signal, for generating a restricted-communication signal upon receipt of said control signal and for a predetermined time thereafter; a transmitter-inhibited subsystem responsive to said restricted-communication signal that inhibits said radio-frequency carrier transmission within the restricted-communication area; and an override mechanism within the cellular telephone responsive to a command set over said radio-frequency carrier, wherein the override mechanism can cause the cellular telephone to ignore the restricted communication signal, thereby permitting radio-frequency carrier transmission within the restricted-communication area.