Detection of traffic congestion in airborne SAR imagery

Detection of traffic congestion is an important issue both for the transportation research community and everyday life of the motorists. Remote sensing sensors installed on aircrafts or satellites enable information collection for various traffic applications over large areas. Optical systems are already in use but are limited due to their daylight operation and cloud-free conditions requirements. Synthetic aperture radar (SAR) systems seem to be more promising due to their allweather capability. We approach the traffic congestion detection problem with a two-channel SAR airborne sensor flying in along-track (ATI) the motorway by combining various techniques: look processing, channel balancing, coherent difference, e.g. displaced phase center array (DPCA), image processing and incorporation of a priori information such as traffic flow model and road network. The potential of the proposed method is demonstrated with airborne E-SAR data collected during the flight campaign over a highway near Munich.