Study on the scheme of traffic signal timing for priority vehicles based on navigation system

This paper presents a new signal timing method. The purpose is to make priority vehicles reach their destinations without delay at a signalized intersection. That is, whenever the vehicles reach a signalized intersection, the signal light is always green. In our scheme, signal parameters of intersections can be changed at any time if needed. The subject vehicle uses the Global Positioning System (GPS) to locate its position. According to these data, we can get the vehicle´s position and speed, then calculate the accurate time when the vehicle reaches the next intersection. At that time, if the indication of the signal light is not green, the timing plan must be changed so that the subject vehicle can be given the right of way to move into the intersection