A complete Highway Advisory Information Radio (HAIR) system was developed for audibly conveying traffic advisory and emergency information to the motoring public using a low power, limited coverage roadside transmitter at dedicated frequencies of 530 kHz and 1606 kHz. Types of information conveyed include emergency messages, warning tones indicating the approach of an emergency vehicle advisory messages to alert motorists of anomalies ahead and alternate routes, and trip needs such as information pertaining to gas food and lodging services. A major objective of the program was the development of special automotive receivers permitting the motorist to automatically receive the traffic messages while listening to his favorite AM or FM broadcast station. The radio transmission system utilized audio tone codes to achieve control of the automatic receivers; however, the system also permitted message reception with over 90 percent of existing AM automobile radios. Surveys of commercial automotive AM receivers were made to determine tuning range limits and receiving sensitivities at 530 kHz and 1606 kHz. It was found that the capability of automotive AM radios to receive out-of-band signals depends almost entirely on field strength and not on the limits of tuning range. /FHWA/

  • Availability:
  • Corporate Authors:

    Atlantic Research Corporation

    5390 Cherokee Avenue
    Alexandria, VA  United States  22314
  • Authors:
    • Anderson, R A
    • Robertson, R G
  • Publication Date: 1974-12

Media Info

  • Pagination: 260 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00097931
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • ISBN: T-0094
  • Report/Paper Numbers: FHWA-RD-74- 73 Final Rpt.
  • Contract Numbers: DOT-FH-11-8045
  • Files: TRIS, USDOT
  • Created Date: Oct 18 1975 12:00AM