The differential interferometry PSI is based on the identification of targets exhibiting good phase stability PS. These targets are available in urban areas, but less available in non-urban areas. For this purpose, the statistically homogeneous pixels DS, permit to this technique to be extended for the non-urban areas. Knowing that homogeneous areas are favourable for a development of the speckle noise, an adaptive filtering is applied to these areas without compromising the phase stability of PS. In this context, we propose in this paper a PS and DS selection strategy based on two steps: first, the PS are selected and isolated using coherence maps, which will allow us to exclude theme from filtering operation. In the second step, the DS selection is processed. This approach has been tested on SAR images acquired by sensors ERS1/2 corresponding to the area of Haoud el Barkaoui, Ouargla in Algeria.
Target geolocation in radar images is becoming more crucial with the advent of high-resolution sensors and the variety of acquisition modes. Each image acquisition system produces specific geometric distortions in its raw images and consequently the geometry of these images does not correspond to the terrain or to a specific map projection of end-users. The geometric distortions vary according to different factors such as the acquisition system (the platform, the sensor and other measuring instruments), as well as the observed surface (problem of earth model, effects of its rotation and the problems inherent to the relief [8]). Nevertheless, it is possible to make general categorizations of these distortions. For RADARSAT 2, image acquisition can be achieved in a wide range of viewing directions [6], and at different resolutions, which implies different geometric distortions, specific to each type of acquisition mode. We also have to take into account the range nonlinearities caused by both the height of target regions and the side-looking acquisition mode of SAR images. We propose a georeferencing process for RADARSAT 2 images, using image metadata. Three levels of treatment were achieved: extracting and restructuring the orbital data from the header file; global modelling of the random distortions to achieve georeferencing, and finally rectifying the range position error caused by elevation in the slant range plane. The process was tested on a set of image data acquired by the RADARSAT2 satellite in both quadri and bipolarisation, covering an area of the capital "Algiers" (Algeria).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.