FREQUENCY MANAGEMENT FOR VEHICLE COMMAND AND CONTROL

PROPOSED AUTOMATIC VEHICLE LOCATION (AVL) SYSTEMS FOR MONITORING BUS AND TAXI OPERATIONS IN AN URBAN SITUATION ARE DESCRIBED. THE AVL CONCEPT WOULD MONITOR A LARGE NUMBER OF VEHICLES OVER AN EXTENSIVE AREA AT A RAPID CYCLE RATE TO PROVIDE DISPATCHERS AND TRANSIT MANAGERS WITH A CONSTANT PICTURE OF THEIR OPERATIONS IN THE FIELD. THE AVL WOULD ALSO PROVIDE ALMOST INSTANTANEOUS INFORMATION ON SCHEDULING, EMERGENCIES, EQUIPMENT STATUS, AND TRAFFIC CHARACTERISTICS. SUCH INFORMATION WOULD SUBSTANTIALLY IMPROVE DISPATCHING, PRIORITY DYNAMIC ROUTING, MAINTENANCE ALLOCATIONS, AND SERVICE FOR BOTH ROUTED AND RANDOM-ROUTED VEHICLE FLEETS. THE BASIC AVL TECHNIQUES ANALYZED WERE GROUPED INTO THE CATEGORIES OF INERTIAL OR DEAD-RECKONING, SIGNPOST OR PROXIMITY, AND TRILATERATION. PROBLEMS WITH THE CONVENTIONAL RADIO FREQUENCY SPECTRUM SUCH AS OVERCROWDING (DUE TO SIMULTANEOUS TRANSMISSION ON PUBLIC WAVELENGTHS), AREA COVERAGE, AND OBSTACLE PENETRATION ARE DISCUSSED IN DETAIL. AN EQUATION TO MEASURE TRANSMISSION PERFORMANCE AS THE FUNCTION OF POWER OUTPUT, TRANSMITTER AND RECEIVER GAIN, FREE SPACE LOSSES, AND OTHER LOSSES WAS DEVELOPED AND TESTED TO YIELD AN OPTIMUM FREQUENCY FOR AVL OPERATION. IN ADDITION TO SPECTRUM ANALYSIS, SECTIONS ON BANDWIDTH ANALYSIS AND SYSTEM EVALUATION ARE CONTAINED. EIGHT SPECIFIC AVL DESIGNS WERE COMPARED WITH REFERENCE TO MINIMUM PERFORMANCE LEVELS, IMPLEMENTATION REQUIREMENTS, AND SPECIAL ADVANTAGES. /UMTA/

• Supplemental Notes:
  • PROJ NO MD-MTD-4
• Corporate Authors:

  IIT Research Institute

  10 West 35th Street
  Chicago, IL  United States  60616
• Publication Date: 1971-4

Subject/Index Terms

• TRT Terms: Automatic vehicle location; Automatic vehicle monitoring; Bandwidth; Buses; Communication systems; Dispatching; Frequency (Electromagnetism); Location; Monitoring; Radio; Scheduling; Spectrum analysis; Taxicabs; Wavelength
• Uncontrolled Terms: Monitors
• Subject Areas: Highways; Operations and Traffic Management; Public Transportation;

Filing Info

• Accession Number: 00226478
• Record Type: Publication
• Source Agency: Urban Mass Transportation Administration
• Files: TRIS, USDOT
• Created Date: Nov 7 1981 12:00AM