Analysis of Vehicle Positioning Accuracy Requirements for Communication-Based Cooperative Collision Warning

Abstract

This article describes an analysis of the use of vehicle positioning and wireless communication technologies to implement collision warning systems without using direct ranging sensors. If the positions and velocities of the vehicles can be known to sufficient accuracy and can be communicated to neighboring vehicles, each vehicle can identify whether it is in danger of colliding with any other vehicle. The probability that useful warnings can be provided is calculated as a function of the accuracy of the vehicle position and velocity information that are available (from Differential Global Positioning System (DGPS) and wheel speed sensors, for example). The analyses are reported for forward collision warnings, lane change warnings, and several intersection conflict scenarios. The governing accuracy requirement for all but the intersection scenarios is associated with the need to assign the vehicles to the correct lanes, which requires a standard deviation of positioning accuracy of about 50 cm in order to support reliable and consistent warnings.