3694579 is referenced by 29 patents and cites 4 patents.

A digital communications system which can be used for emergency reporting having a transmitting unit which sends out information signals identifying the transmitting unit and identifying the type of emergency. A relay station located within the area receives and stores the signal and in response thereto electronically dials a predetermined telephone number to a data center, transmits an encoded signal identifying the station and then relays the information sent from the transmitting unit. Assistance or corrective action may then be provided by dispatch from the data center.

Title
Emergency reporting digital communications system
Application Number
05/169,737
Publication Number
3694579
Application Date
August 6, 1971
Publication Date
September 26, 1972
Inventor
McMurray Peter H
IPC
H04m 11/04
H04M 11/04
G08B 27/00
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