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Smart Sensor Systems for Outdoor Intrusion Detection (From Proceedings, 1988 Carnahan Conference on Security Technology: Electronic Crime Countermeasures, P 45-49, 1988, R. William De Vore, ed., -- See NCJ-117849)

NCJ Number
J K Lynn
Date Published
5 pages
A major improvement in outdoor perimeter security system probability of detection and reduction in false alarm rate and nuisance alarm rate may be obtained by analyzing the indications immediately preceding an event which might be interpreted as an intrusion.
Existing systems go into alarm after crossing a threshold. Very slow changes, which accumulate until the threshold is reached, may be assessed falsely as an intrusion. The ability to "look into the past" on a real-time basis adds a new dimension to alarm reporting and monitoring. This is done by converting analog data to digital data and storing it in serial form in memory. Since this stored data may be accessed and transmitted in reverse order, the immediate pre-trigger event history would be available for alarm decision making. 2 figures, 4 references. (Author abstract modified)