Within this project, the optimal satellite constellation to collect traffic data is developed. Satellites, sensors, methods and constellations are examined and developed in theoretical approaches.
Radar based picturing methods combined with Moving Target Indication methods (SAR/MTI) (see project TerraSar-X data products for transport research) have the potential to contribute to transport research. A significant conclusion of modern transport research is that traffic is taking place on a spatial level, because traffic networks are always established spatially. Because of this core statement, satellite systems, with their possibilities and advantages to gather wide aerial data, are admitted great chances in transport research.
Non-radar based methods working with technical sensors like video cameras or laser sensors to collect traffic data are widely established. The traffic data is collected solely at a few fixed points. With another concept, the Vehicle Probes method, traffic data is collected via vehicles which float within the traffic-flow. Based on the gathered data, information about the actual traffic status of the appropriate section of road is derived. These concepts do not offer wide aerial collection of transport data. For example the ground-based sensors, which are widely in use in Germany, are less widespread in other European countries.
In contrast to these methods, space borne traffic data collection offers the ability of wide aerial traffic data collection. This is a decisive advantage compared to ground based methods, because the cross-border fleet management could strongly contribute to improve the road network capacity and therefore to an economic and in a final step to an ecological improvement.
By using air borne and space borne methods it is possible to get an overview of the traffic situation. Air borne SAR-sensors for data collection are tested. Yet, a complete traffic monitoring with this method would be quite expensive because of the high logistic complexity. Therefore, space borne methods to collect traffic data which collect data on a wide aerial level are being discussed at present. The results of reference systems like MultiSat WebService have shown that the collection of wide aerial data collection is technically feasible today.
The DLR possesses twenty years of research experience on methods based on radar with synthetic aperture (SAR). With that method it is possible to display objects and the surroundings. Radar offers various advantages compared to optical or infrared-systems like great range, penetration of weather phenomena like clouds, fog, snow or dust and the day and night working ability. Yet, momentarily the SAR technology is not adequate to properly detect vehicles. Within the project TerraSar-X data products for transport research new modes are developed, which can be used for tests concerning transport research.
Project Duration: January 2004 - December 2006, Follow-on projects: ARGOS and VABENE