A Study On Remote Dial-up Green-wave Traffic Signal Control System

Traffic control is one of the key factors to urban development. Adapting to the present circumstances of the traffic control in Tianjin city and applying the new control technology, this thesis illustrates how to build up long-distanced green wave traffic signal control system (LGWTSCS) in realizing green wave coordinate control for main artery.In the first part of this thesis the present circumstances and existing problems of the traffic signal control in Tianjin are analyzed. In terms of the analytical results, design of the LGWTSCS, make systematical analysis of the architecture, function, complement process and the information structure of the LGWTSCS are put forward. In addition, the database design solution is also given. The LGWTSCS is composed of central controller and intersection controller. Based on Microsoft SQL Server database and adopting the mode of client/ server(C/ S), the software system of central controller is mainly divided into four subsystem: database system, traffic management information system, communication system and geography information system (GIS).The intersection controller is based on STD bus structure, its processor adopting MSC-89C51 monolithic computers of the INTEL company. Then, a two-way offset-adjusting Algorithm for green wave traffic signal control is proposed, which can shorten the transition time and high ten the performance of controller.At last, we present the performances and results of the application of LGWTSCS in several intersections of Tianjin, which indicate that this system can reduce the frequency of car stopping and raise the speed of motor-vehicle and the capacity for more traffic on the main arteries.