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Intertidal flats are productive and rapidly changing places. However, these places are facing many environmental challenges related to climate change and human-induced impacts. Topographic change due to sedimentation or erosion in intertidal flats can be the key indicator for recognizing these environmental changes. The intertidal flats usually have small topographic variations (less than 5m) and...
Clutter suppression is a key step for efficient detection of moving targets and accurate estimation of their parameters. Current clutter suppression approaches are available, in the case that clutter echoes of each channel are free of Doppler ambiguity. However, for multichannel high-resolution wide-swath (HRWS) synthetic aperture radar (SAR) system, the received echoes of each channel suffer Doppler...
A targets detection algorithm is proposed for maritime surveillance by single-channel SAR images. It foresees a preliminary prescreening step, carried out using an adaptive threshold algorithm, followed by a discrimination phase, performed by sub-look analysis. The latter discriminates the pixels detected by the former step in three classes, i.e. targets, sea, and azimuth ambiguity. The algorithm...
This paper proposed a method of combining the Modified Normalized Difference Water Index (MNDWI), morphological operators (MOs) and seeded region growing (SRG) to extract waterline information from remote sensing satellite images, and applied this approach to a long period (from 1987 to 2010) Landsat TM dataset to acquire the waterline changes in the coastal wetlands in the Yellow River Delta (YRD)...
In this paper we propose a new extraction scheme for linear arranged targets in polarimetric SAR images based on a contrario theory. In this scheme, to reduce the influence of speckle, firstly a polarimetric whitening filter is applied to combine four images from different channels into a single channel image. Then a Cell-Averaging Constant False Alarm Rate detector with Weibull clutter background...
In this paper, an interferometric synthetic aperture radar phase denoising method which utilizes both local sparsity of wavelet coefficients and nonlocal similarity of grouped blocks, has been proposed. The derived nonlocal wavelet shrinkage use double L1 norm restrictions, which enforce local and nonlocal sparsity constraints by efficient shrinkage operators. This method can take advantage of the...
In order to verify the supplementary effect of radar remote sensing on optical remote sensing in geological applications, an experimental study on the use of fully polarimetric radar data for lithologic classification is carried out. First, the ASTER data are used to classify the lithology, and then the ASTER and RadarSAT-2 data are superimposed on the lithology classification, and the results are...
In this study, we focus on the investigations of oil slicks observed by TerraSAR-X and TanDEM-X operating over the drilling platforms in Forties oil field, the largest one in the North Sea. Previous researches indicate that oil spills observed by consecutive SAR images represent the same leaks, but in this paper, we presented four cases which suggest completely different situations of oil spill variations...
The accumulation and impacts in the ocean of marine debris generated by anthropogenic activities and aggravated by natural disasters are of growing concern, yet our existing data collection systems are rudimentary and cannot answer even fundamental questions. This is partly due to the diversity of the debris and the vastness of the ocean that complicate observations. The magnitude and complexity of...
In this paper we show that hyperspectral imaging systems are able to improve the detection and characterization Hazardous and Noxious Substances (HNS) in the case of marine pollution. We analysed nadir hyperspectral image acquisitions from 0.4 to 12µm corresponding to two different campaigns: (i) HNS release at the surface of a sea water pool; (ii) HNS release in the Mediterranean Sea under real conditions...
Numerical simulation of brightness temperatures of the Advanced Microwave Scanning Radiometer 2 (AMSR2) over the sea ice-open ocean-atmosphere system is fulfilled for non-precipitating conditions using a database of atmospheric meteorological parameter profiles, model profiles of cloud liquid water and published experimental data for sea ice emissivities. The results of numerical experiment show that...
Polar lows (PLs), emerging over the sea ice edge, are studied using multisensor data information, surface analysis maps and reanalysis data. PLs over the Western (the Greenland, the Norwegian and the Barents Seas), and the Eastern (the Chukchi, the East Siberian and the Laptev Seas) parts of the Arctic are considered. It is shown that currently operating satellite instruments, taken separately, cannot...
We calculated Antarctic sea-ice freeboard and thickness for ICESat and ATM campaigns. A Gridded ATM freeboard map of nine IceBridge campaigns in October 2009, 2010, and 2011 is shown in Figure 1.
Ground based interferometric radar (GBIR) is a revolutionary advanced measurement technique for geoscience and engineering geodesy. It is powerful for temporally and spatially dense measurements of highly dynamic target with sub-millimetric accuracy, especially in man-made structures, e.g. buildings, towers, dams and bridges. In this case study, we use a real aperture radar system, the Gamma Portable...
In this paper we present an algorithm for sea ice concentration estimation in the Arctic from C-band dual polarization Sentinel-1A SAR images. The algorithm is based on spatial autocorrelation and utilizes an artificial neural network to map the image information to sea ice concentration. The cross-polarization channel facilitates the improvement of concentration estimates of images with high backscatter...
An experiment to examine the detectability of volcanic ash cover and its thickness by using L-band synthetic aperture radar (SAR) was carried out. Test sites with 0, 10, 20, and 40 cm ash layers were developed. PALSAR-2 and Pi-SAR-L2 observations were carried out several times with and without the ash cover. The PALSAR-2 backscatter coefficients in HH polarization, σHH0, for soil with ash layers are...
The radiometric quality of polarimetric SAR (PolSAR) image is affected by terrain undulations due to 1) the variation of effective scattering area, 2) the variation of scattering mechanisms, and 3) the variation of polarization states. This paper proposed a three-stage terrain correction method of PolSAR data for the impact of above three aspects. PALSAR-2 PolSAR data and LiDAR forest AGB data are...
AfriSAR is an ESA-funded airborne P-band SAR campaign over the African tropical forests of Gabon that is being carried out by ONERA (July 2015) and DLR (February 2016) in support of the development of the geophysical algorithms of the future BIOMASS mission. Multibaseline fully-polarimetric acquisitions have been designed over four test sites in order to further develop and validate algorithms for...
Polarimetric SAR Interferometry (Pol-InSAR) is a SAR remote sensing discipline with unique and powerful applications related to the vertical structure of natural and man-made volume scatterers. The coherent combination of single- or multi-baseline interferograms acquired at different polarisations provides sensitivity to the vertical distribution of scattering processes and allows their characterisation...
This paper proposes a custom convolutional deep belief network for polarimetric synthetic aperture radar (PolSAR) data feature extraction. The proposed architecture stands out through the interesting features it shows, starting with the fact that it is adapted to fully polarimetric SAR data. Then, the multilayer approach allows the stepwise discovery of higher-level features. The convolutional approach...
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