Patent ID: 8391826

Claim:
A Reverse 911 Alarm System for transmitting an alarm indication to individuals served by at least one cellular communication network, each of said cellular communication networks serving an associated plurality of cellular communication devices, each of said cellular communication devices being capable of generating a human sensible output to warn individuals who use said cellular communication devices of a hazard condition, comprising: an alarm controller, responsive to receipt of alarm data indicative of the presence of a hazard condition, for generating at least one alarm indication; a hazard coverage area determination means for dynamically defining a coverage area indicative of a geographical extent of the hazard condition, including a list of cell sites that provide cellular service to the coverage area indicative of the geographical extent of the hazard condition; a hazard alarm distribution control means for transmitting the alarm indication to cell site controllers which are associated with the cell sites in the list of cell sites having a communication coverage corresponding to the geographical extent of said hazard condition; cellular communication device identification means, operational in each of the cell site controllers which are associated with the cell sites in the list of cell sites, for identifying all cellular communication devices which are active in the cell site; and a cellular multicast means, operational in the cell site controllers which are associated with the cell sites in the list of cell sites, for concurrently transmitting the alarm indications via a single multicast to a plurality of the identified cellular communication devices to generate human sensible output to warn individuals who use said cellular communication devices of the hazard condition.