Automatic vehicle identification: Tests and applications in the late 1970's

To identify a vehicle uniquely and automatically as it passes on the roadway without requiring any action by the driver, one general approach uses a transponder on the vehicle and an interrogator by the roadside. When the identity is passed from the interrogator to a data system which may have data storage, retrieval, computation, display, and actuation capabilities, various functions such as charging for the use of road or parking facilities, fleet management, and fine grain traffic control become possible. The main purpose is to report recent testing of such systems and consider some probable early applications. At the outset, however, the functional requirements are discussed in more detail, and the background of automatic vehicle identification (AVI) development and testing is briefly reviewed.