Metropolitan expressway, since its service starting in 1962, has extended to the length of 270km in total as of 2002, conveying 1.16 million vehicles a day. It has introduced a traffic control system to increase the processing capacity and enhance the service to drivers. The system is located in three areas: West Tokyo area, East Tokyo area and Kanagawa area to collect, process and indicate the expressway traffic condition. Among which, Kanagawa area traffic control system was introduced in 1989 and its present processing capacity had reached its limit due to data increase caused by the complexity of information provided and opening of new routes. Thus, it was decided that the Kanagawa area system be enhanced with introduction of additional functions.
Abstract