Verification Of Traffic Information Using Advancd Radar Satellites

Abstract

Modern traffic information systems base on several sources of raw data like from induction loops, cameras, floating cars, cell phones, call-ins from drivers and traffic models. Typically, they provide maps with annotated road segments, indicating the average speed and travel time or they feed the information directly into the navigation system of the cars. The verification of such large traffic maps is very difficult; because “ground truth” activities which make use of cameras or floating data are man-power intensive and they can only deliver point-like measurements. In this paper we introduce a satellite based system which can overcome these problems. We report from a joint IFSTTAR / DLR test campaign which has been conducted in May 2010. Test sites near Paris, Lyon and Marseille have been observed by the German radar satellite TerraSAR-X several times and the traffic maps generated from these snapshots from space can be compared with results from the in-situ measurements. We report from a first comparison which has been performed on the motorway A50 east of Marseille. Furthermore, the paper provides a brief summary of the satellite based traffic acquisition and processing chain which has been developed at the German Aerospace Center DLR.