The feasibility of traffic monitoring with TerraSAR-X - analyses and consequences

This paper analyzes the potential of the upcoming German satellite mission TerraSAR-X to monitor traffic from space. As it is well-known, an object moving with a velocity deviating from the assumptions incorporated in the focusing process will generally appear both displaced and blurred in azimuth direction. To study the impact of these (and related) distortions in focused SAR images, the analytic relations between an arbitrary moving point scatterer and its conjugate in the SAR image have been derived and adapted to the TerraSAR-X specifications. To be able to monitor traffic under these boundary conditions in real-life situations, a specific detection strategy is proposed. This strategy makes use of knowledge derived from external sources, as e.g. GIS and semantic models for traffic flow.