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AUTOMATIC VEHICLE LOCATION TECHNIQUES FOR LAW ENFORCEMENT USE - LAW ENFORCEMENT STANDARDS PROGRAM

NCJ Number
14189
Author(s)
RL FEY
Date Published
1974
Length
42 pages
Annotation
THREE TYPES OF AUTOMATIC VEHICLE LOCATION TECHNIQUES DEAD RECKONING, PROXIMITY, AND RADIOLOCATION - ARE COMPARED FOR LAW ENFORCEMENT APPLICATIONS.
Abstract
IN ORDER TO DISPATCH PATROL CARS EFFICIENTLY, PRECISE KNOWLEDGE OF CAR LOCATION IS NECESSARY. THE EARLIEST CAR LOCATION METHODS SIMPLY ASSIGNED PATROL CARS TO SPECIFIC SECTIONS (OR BEATS) OF THE CITY WITH THE ONLY ASSUMPTION BEING THAT THE CAR WOULD BE FOUND SOMEWHERE WITHIN THE BEAT. CURRENT DISPATCHING METHODS HAVE EVOLVED FROM THIS BEGINNING AND PRESENTLY SEVERAL COMMERCIAL FIRMS ARE DEVELOPING AUTOMATIC VEHICLE LOCATION (AVL) SYSTEMS WHICH EMPLOY COMMUNICATIONS TECHNIQUES. 'DEAD RECKONING' IS A CAR-BORNE POSITION COMPUTATION AND REPORTING SYSTEM. THE 'PROXIMITY' SYSTEM USES PATROL CAR EMITTERS AND CALLBOX SENSORS TO IDENTIFY A VEHICLE WHEN IT PASSES NEAR CERTAIN FIXED LOCATIONS. 'RADIOLOCATION' IS A RADIO DIRECTION-FINDER SYSTEM THAT EMPLOYS METHODS OF TRILATERATION, TRIANGULATION AND NAVIGATION AND RELIES ON MORE THAN ONE FIXED RADIO TERMINAL FOR OPERATION. THE IMPORTANT CHARACTERISTICS, ACCURACY, FREQUENCY SPECTRUM REQUIREMENTS, AND COVERAGE AREA OF EACH TECHNIQUE ARE COMPARED AND DISCUSSED. THE COSTS OF SUCH SYSTEMS ARE ALSO CONSIDERED. AN ANNOTATED BIBLIOGRAPHY IS PROVIDED. (SNI ABSTRACT)