Signal Offset Optimization in Coordinated Signal Control System Based on Cointegration Theory

Coordinated signal control can effectively ease urban traffic congestion, because which can improve the continuity of traffic flow movement and reduce delay. Real-time green light starting time setting is the key for practical engineering application of coordinated signal control system. Signal offset between adjacent intersections determines green light starting time. But traditional traffic control systems assuming signal offset being one or several fixed numbers can´t express the volatility and random of traffic flow movement. In order to increase the benefit of coordinated signal control, this paper adopts the nonlinear cointegration theory and model in economics to optimize signal offset based on a series of strict applicability tests with the practical data in Shanghai. The comparative results with actual statistical data are encouraging, the maximum reduction of travel time and delay are up to 38.12% and 45.65%.