DUAL SITE SUPERVISION FOR CONTROL CHANNEL CELLULAR RADIO USED IN A FIRE ALARM REPORTING SYSTEM

摘要

Dual site supervision is provided for a control channel cellular radio for afire alarm reporting system that uses logic that causes a control channelcellular transceiver to operate in a nonstandard manner and to use a differentand second cellular base station or site that the unit would not normallyselect operating pursuant to a standard cell phone software module. The logiccauses the control channel cellular transceiver to monitor and test throughmore than one cell base station or site, thereby meeting the dualcommunication path supervision requirement for UL listed communicationssystems for stand alone fire alarm reporting systems. The available cellularcontrol channels are first scanned, and the signal strength of each cellularcontrol channel is measured. Then the cellular control channel with thestrongest signal strength and the cellular control channel with the secondstrongest signal strength which are verified as being available for theassigned carrier are selected to report the status of the fire alarm system. Acellular radio message on the status of the fire alarm system is transmittedover the cellular control channel with the strongest signal strength, or ifunavailable over the cellular control channel with the second strongest signalstrength.