Remotely controlled traffic light system - includes central controller communicating via telephone lines with inductive loop local traffic detectors and light controllers

摘要

The system includes a central control station (PCR) connected by two-wire lines, e.g. telephonse lines, to a number of remote stations (STC1-4). Each remote station is connected to a local unit which is either a light controller or a traffic detector. For example the first station (STC1) is associated only with a traffic light controller (CTE1), while the third station (STC3) is associated with a traffic detector (DT2). Other remote stations may serve both purposes. The central station includes a real time clock, and periodically transmits information to the remote stations. These in turn send back traffic information and information about the operation of lights. Traffic detectors may be electromagnetic loops situated under the road to sense the passage of vehicles.