Acquisition of traffic status information is the basic problem in Urban Road Traffic Control.The existing road traffic control system which takes focus on processing information in central processing computer results in the pressure of data transmission and processing.And as the deployments of bottom sensors are independent of each other,the system can not form the sensor network to acquire traffic status in whole time-space.In response to these problems,a distributed method of traffic status acquisition based on sensor network is introduced into this paper.Bottom layer adopts fieldbus CAN transmission which is high reliability and easy to form network, while upper layer uses the Ethernet communication which is high-speed and informative.The system consists of access nodes,composite nodes and a central computer.
