Spatial and temporal analysis of probe vehicle-based sampling for real-time traffic information system

Using vehicles as probes is a flexible and low-cost way to obtain real-time traffic information. This paper addresses the sampling issues of using probe vehicles for detecting traffic information in a road network. A spatial and temporal analysis model based on signal processing theory is established and used to derive bounds on the sampling period, transmitting period and sample sizes of probe vehicles. We also develop a Traffic & Information-collecting Simulation Platform (TISP), to simulate the traffic flows in a road network and generate probe vehicle data for analysis. The simulation results find that traffic flow has strong correlation in terms of time and space, which is critical to the sampling problem, and the system requires 2% probe penetration to guarantee the information integrity.