A review of the applications of SAR polarimetry and polarimetric interferometry - an ESA funded study

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An adaptive solution for the detection of small and slowly-moving targets in highly ambiguous radar context

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ESTIMATION OF THE VERTICAL STRUCTURE OF A TROPICAL FOREST USING BASIS FUNCTIONS AND PARAMETRIC SAR TOMOGRAPHY

International audienceSAR tomography represents a unique way to characterize forested areas from their 3-D density of reflectivity. As shown by numerous studies, coherent 2-D SAR images with intermediate horizontal resolution may be processed through spectral analysis techniques in order to focus 3-D cubes of reflectivity, and to provide an electromagnetic description of forets which is generally sufficient to estimates its main features, such as underlying ground topography, tree height and above-ground biomass. Nevertheless, a refined analysis of the vertical structure of a forest is usually highly limited by the vertical resolution and by the presence of side-lobes and focusing artifacts whose separation from the actual response may be problematic. As shown in this paper, direct deconvolution of the vertical impulse response using high-resolution techniques is an underdetermined inverse problem with an infinite number of plausible solutions. The use of basis functions, such as those proposed by Aguilera et al. [1], as well as a set of signal properties likely to be well adapted to the reflectivity of forested areas, allows to drastically reduce the size of the solution domain. This paper iuses an efficient iterative technique to estimate the intrinsic vertical reflectivity profile of forest measured at L and P band

C-Band 2×2 MIMO multi-carrier tomographic radar for complex environment volumetric imaging

International audienceIn this paper, we present a C-Band 2 ×2 MIMO Multi-Carrier Radar system that has been realised at the IETR laboratory and a new modulation technique that permits to avoid the use of switches. To validate this system, measurements have been done with two trihedral corner reflectors lying on a grass field, using our system and a VNA. We have processed the acquired data using the Back Projection Algorithm (BPA). VNA and MIMO-MCR give similar results with a vertical resolution of 0.37 [email protected] m ground range and a vertical ambiguity of 0.74 [email protected] m ground range. Therefore, the system is fully operational. © 2018 IEEE

Adaptive processing for spaceborne monitoring of forests using SAR tomography

This paper proposes different processing techniques for the polarimetric 3-D imaging of forested areas using multibaseline interferometric SAR data, acquired in TanDEM configuration from spaceborne SAR sensors. TanDEM-like acquisition modes, based on the simultaneous measurement of interferometric pairs, represent a high-potential alternative for the tomographic imaging of scenes with rapidly decorrelating scattering features using a spaceborne SAR. Unlike coventional tomographic processing, this correlation tomography requires specific processing techniques to estimate the covariance matrix from single-pass InSAR pairs that are uncorrelated one from another. These techniques are proposed in this paper and their potential for boreal forest characterization are evaluated in the frame of the preparation of the SAOCOM CS mission using ESA’s BIOSAR II campaigna data sets acquired at L band by the DLR ESAR sensor