NCJ Number
57722
Date Published
1976
Length
5 pages
Annotation
THIS PAPER PROVIDES A DESCRIPTION OF THE GUIDED INTRUSION DETECTION AND RANGING (GUIDAR) SYSTEM, WHICH IS SAID TO BE CAPABLE OF DETERMINING THE LOCATION OF ANY PERSON ATTEMPTING TO CROSS A RESTRICTED PERIMETER.
Abstract
THIS SECURITY TECHNIQUE BASED ON THE PRINCIPLE OF GUIDED RADAR, WAS DEVELOPED UNDER CONTRACT FOR THE CANADIAN PENITENTIARY SERVICE. A PAIR OF SO-CALLED LEAKY COAXIAL CABLES, SEPARATED BY SEVERAL FEET, ARE LAID AROUND THE PROTECTED AREA AND ACT AS THE SENSING ELEMENT. A PULSE OF ENERGY PROPAGATING DOWN ONE OF THE CABLES INDUCES A TRAVELING ELECTROMAGNETIC FIELD EXTERNAL TO THE CABLE. AN OBSTACLE IN THE VICINITY OF THE CABLE PERTURBS THIS FIELD AND THE RESULTANT REFLECTION INDUCED INTO THE SECOND CABLE IS USED TO DETERMINE THE OBJECT'S LOCATION. THE RETURN SIGNAL IS PROCESSED BY SPECIALIZED DIGITAL HARDWARE, INCLUDING A HIGH SPEED MICROPROCESSOR, IN A MANNER WHICH TAKES ADVANTAGE OF THE ELECTROMAGNETIC CHARACTERISTICS OF THE CABLES. THE EVENTUAL OUTPUT IS PROVIDED TO THE OPERATOR VIA AN AUDIBLE ALARM AND A MIMIC LOAD DISPLAY COMPRISING ONE LIGHT EMITTING DIODE PER HUNDRED FEET OF PERIMETER. A NUMBER OF PROTOTYPES OF THE SYSTEM HAVE BEEN TESTED AT QUEEN'S UNIVERSITY, KINGSTON, ONTARIO AND AT COMPUTING DEVICES COMPANY, OTTAWA UNDER FULL ENVIRONMENTAL CONTROL. RESULTS OBTAINED TO DATE INDICATE THAT THE FOLLOWING DESIGN OBJECTIVES HAVE BEEN MET: (1) INDEPENDENCE OF SITE TOPOLOGY, (2) ALL WEATHER CAPABILITY, (3) LOW FALSE ALARM RATE (1 PER 48 HOURS), AND HIGH DETECTION PROBABILITY (99.5 PER CENT). SYSTEM DESIGN FIGURES AND EXPLANATIONS ARE PROVIDED, AND REFERENCES ARE FURNISHED. (AUTHOR ABSTRACT MODIFIED--MHP)