A total highway communications system using F1-F1repeaters

As part of the future improvement of the nation´s highways, the Bureau of Public Roads is planning a two-way communications system. This system will incorporate various sensors to provide for better control and also many safety and convenience services which would be desirable for more efficient use of the highways. A unique radio system confined to highway right-of-way which is economical and has the inherent growth capability which would be required for a nationwide system is outlined. The design concept makes use of recently developed F1-F1repeater techniques which would result in a nationwide system requiring only two radio frequencies, one from the headquarters´ control to the cars or trucks and one from the car to the headquarters. The highly stable roadside frequency is transmitted from the local headquarters´ control point and confined to the highways on an F1-F1repeater system. The car equipment is a transponder unit whose frequency is controlled by the highway system. Automatic location identification of the car signal is provided. Signals can be either voice or digital. For growth and integration with other special services such as car or truck identification, traffic control, route guidance, etc., time-sharing channels can be added to both the highway system and to those cars that require it.