NCJ Number
39902
Date Published
1975
Length
4 pages
Annotation
ARTICLE DESCRIBES RADIO POSITIONING SYSTEMS FOR LOCATING AND KEEPING TRACK OF VEHICLES.
Abstract
CONTROLLERS OF PUBLIC SERVICE AND UTILITY VEHICLES OFTEN FIND IT NECESSARY TO KNOW WHERE THEIR VEHICLES ARE ON THE ROAD. RADIO METHODS AVAILABLE TO LOCATE THEM ARE SUBJECT TO COMPLEX AND CONFLICTING REQUIREMENTS OF ACCURACY, INFORMATION RATE, AND RADIO SPECTRUM UTILIZATION. RADIO POSITIONING SYSTEMS ARE GENERALLY BASED ON THE MEASUREMENT OF DISTANCES FROM FIXED TRANSMITTING STATIONS, AND JUDGE THE TIME DIFFERENCES BETWEEN THE ARRIVALS OF THE SIGNALS FROM THE VARIOUS STATIONS. THE ARTICLE BRIEFLY DISCUSSES THE BENEFIT OF VHF AND UHF RADIO IDENTIFICATION SYSTEMS AND RADIO TRANSMITTING FREQUENCIES. VIDEO DISPLAY SYSTEMS AND RADIO TELEPHONE SYSTEMS ARE ALSO COVERED, ALONG WITH CONTROL CENTER EQUIPMENT....BS