Real-time Urban Traffic Sensing with GPS Equipped Probe Vehicles

GPS-based Vehicle Probe (GVP) has become an important floating car source in Intelligent Transportation System (ITS) for its efficiency and accuracy. We develop a real time GVP traffic estimation system in Taiwan by collecting the GPS data of commercial fleet and taxi. After filtering out some improper data, the retained GPS data are processed by an incremental map matching method which maps the GPS trajectories to real road map concerning of latency and accuracy. Then, road speed information can be produced by Speed Estimation module. To supply traffic information for public, road speed information are summarized and broadcast through a traffic information website. The experiments show that our system can reach good map matching accuracy and traffic information accuracy. Therefore, reasonable traffic information of freeways and urban areas can be sensed efficiently.