In this paper, an advanced technique for the generation of deformation maps using SAR (Synthetic Aperture Radar) data is presented. The algorithm estimates the linear and non-linear components of the displacement, the error of the Digital Elevation Model (DEM) used to cancel the topographic terms, and the atmospheric artifacts from a reduced set of low spatial resolution interferograms. The pixel candidates are selected from those presenting a good coherence level in the whole set of interferograms and the resulting non-uniform mesh tessellated with the Delaunay triangulation to establish connections among them. The linear component of movement and DEM error are estimated adjusting a linear model to the data only on the connections. Later on, this information, once unwrapped to retrieve the absolute values, is used to calculate the non-linear component of movement and atmospheric artifacts with alternate filtering techniques in both temporal and spatial domains. The method presents high flexibility with respect the required number of images and the baselines length. However, better results are obtained with large datasets of short baseline interferograms. The technique has been tested with ERS SAR data from an area of Catalonia (Spain) and validated with on-field precise leveling measurements.
This paper presents a numerical tool able to generate realistic SAR images from accurate vessel models for a given orbital sensor. Its capability to extract high resolution radar signatures converts this SAR simulator in a useful tool for vessel classification studies and, furthermore, to define a future constellation of SAR sensors bound for carry on an automatic vessel monitoring system. This SAR simulator has low computational requirements as it is based on high
frequency electromagnetic calculations making feasible to run it in a simple PC. In this paper, the main scheme of the simulator and its capability to consider the vessel velocity and the ocean waves, which can produce an important distorting effect in the final SAR images, will be presented as well as some validation results and particular aspects of vessel modeling. Finally, some examples of radar signatures of precise fishing vessel models are exposed.