| 摘要 |
A system is provided for enhancing the reliability of rescue services by providing a 911 back-up system in which the termination of an emergency call is sensed followed by dialing the telephone number of a predetermined dispatch office (30), with the dispatch office (30) providing a call back to the nearest PSAP (28) to ascertain whether or not rescue is on the way. In one embodiment for cellular phone applications, termination of the emergency call is sensed by detecting the call-in-progress flag (20) available on the phone's bus. In another embodiment, the originating phone (10) transmits the telephone number of the originating phone to permit personnel at the dispatch office (30) to call the originating phone back to ascertain the nature of the problem and if dispatched help has arrived.
|
