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Analysis of L-band polarimetric SAR data has not been extensively carried out for undulating, heterogeneous and fragmented landscapes, where classification can become quite challenging. This paper reports results of a study on the pixel-by- pixel unsupervised classification of very-high resolution polarimetric images by self-organizing neural networks.
It is a challenging problem to automatically register the SAR and optical satellite images in remote sensing applications. In this paper, a novel intensity based multiscale registration method using steerable Simoncelli filters is proposed to register JERS-1 SAR and ASTER images. The mutual information is used as the similarity measure, and a hybrid search technique is used to do the parameter optimization...
This contribution addresses the utilization of near field 3D-SAR imaging algorithms applied to radar data from an ultra wideband (UWB) ground penetrating radar (GPR) system. The measured data were collected at the test field of the multi sensor mine signature (MsMs) group at the European Joint Research Centre (JRC) in Ispra/IT. The layout of this test field was designed for the more difficult problem...
The paper focuses on the multiple roles and advantages of the use of remotely sensed, especially COSMO/SkyMed, imagery in the context of flooding-event prevention and management, describing a support system for civil protection from floods and some of the image processing and analysis techniques involved in.
The aim of this work is to present a process to enhance the image feature of the surface signature produce by the SAR sensor of the convective chimney discovered in March 2001 in the Greenland Sea. The procedure developed to extract the feature is described and some examples of the results of this study are presented and discussed.
Ship signatures in synthetic aperture radar (SAR) imagery have been matched to Automatic Identification System (AIS) data to yield a large database of known ships for ship signature analysis. This paper focuses on ship radar cross section and ship length derived from the ship signature length. Cross- polarization is an attractive option for ship detection.
A new empirical algorithm-CWAVE [1] was developed at the German aerospace center (DLR). A global dataset of two years (September 1998 to December 2000) of ERS SAR data was reprocessed to more than one million SAR imagettes. Met ocean parameters like significant ocean wave height (Hs), wind speed (U10) and mean wave period (Tm-10) are derived from the SAR images using the CWAVE algorithm [1]. The results...
In this paper, we investigate a case-based reasoning (CBR) method for the classification of multi-temporal SAR images with the aid of ancillary information. Our scheme for the problem of multi-temporal SAR images classification comprises four main steps, including SAR image processing, construction of case library, case-based classification and post- classification processing. During the construction...
Oil-spill detection from radar imagery is complicated task in Estonian coastal sea where look-alikes caused by ice, upwelling events, cyanobacterial blooms may occur. We compared SAR image with the MODIS optical imagery and look-alikes caused by upwelling event and cyanobacterial bloom were detected from images of August 7, 2007. Analysis of MODIS imagery from years 2000-2006 showed that during the...
Multi-Dimensional (MultiD) SAR imaging is a modern technique, based on coherent SAR data combination, aimed to space (full-3D) and space deformation-velocity (4D) analysis. It extends the concept of SAR interferometry and differential interferometry and offers new options for the analysis and monitoring of ground scenes. With this regard, we discuss the current status and the results obtained by processing...
This paper deals with the exploitation of dielectric properties of saline deposits for the detection and mapping of moisture in arid regions on both Earth and Mars. We then present a simulation and experimental study in order to assess the effect of salinity on the permittivity of geological materials and therefore on the radar backscattering coefficient in the [1-7 GHz] frequency range. Dielectric...
The possible contribution of bistatic radar measurements to estimate bare soil moisture and vegetation biomass is investigated by a simulation study based on well established electromagnetic models (both coherent and incoherent components). The best system configuration, in terms of observation directions, polarisations and frequency has been singled out by predicting the retrieval accuracy. This...
The Canadian Space Agency's Hurricane Watch program monitors tropical cyclones worldwide and acquires RADARSAT-1 Synthetic Aperture Radar imagery to provide experimental datasets to the scientific research community interested in surface wind field studies. The current HW archives spans from 1999 to 2006 and contain a variety of tropical cyclones from around the world. The images show various storm...
In this presentation, the polarization ratios were calculated from AIRSAR polarimetric SAR data and ENVISAT ASAR dual-polarization data; and their empirical CC parameters which depend on incidence angle were obtained. Five C band HH polarization RADARSAT-1 SAR images are used to validate these polarization ratios and we found that the empirical parameter alpha = 0.5 is superior to other possible parameter...
In this paper we present a variational method for synthetic aperture radar (SAR) speckle removal. Variational method is a newly developed technique for the removal of SAR's multiplicative noise. For an image, we could define an energy functional. The energy evolves as the original image changes, and the minimum energy corresponds to the speckle reduced result. Partial differential equation (PDE) technique...
Common efficient SAR processing algorithms are based on nominal operational conditions. Unfortunately, due to atmospheric turbulences and maneuvering errors, these conditions are often violated in real SAR systems. Hence, a crucial problem in most airborne SAR systems is the compensation of motion errors; if not corrected, the image quality will considerably degrade. A first-order motion compensation...
Bistatic SAR systems are an emerging research field. In which context, the Universitat Politecnica de Catalunya is developing a ground based bistatic system using ESAs ENVISAT and ERS-2 as transmitters. In this paper we characterize the bistatic interferometric phase and the different sources of decorrelation. We will also present a bistatic interferometric simulator which is able to generate realistic...
Joint Time Frequency Analysis (JTFA) is a powerful analysis tool in SAR image processing. At the heart of this process are the Time-Frequency Representations (TFR's) such as the Wigner-Ville distribution (WVD), which is difficult to use because of its large cross-product terms. The pseudo-WV TFR reduces the cross terms by smoothing the integration defining the WV transform. The Time-Frequency Distribution...
Phased array antennas play an important role in many radar applications and their use has increased during recent years in space-based remote sensing applications. Their success is mainly due to high agility in reconfiguring pattern, quick steering capability along both elevation and azimuth axis, easy packaging on spacecraft, low sensitivity to T/R module failures, high achievable directivities....
In the framework of the COSMO-SkyMed mission1, Space Engineering has designed and manufactured four Active Calibrators (AC). An AC has a twofold function: ldr re-radiating the received radar signal with the required Radar Cross Section (RCS) and polarisation; ldr acquiring the received Synthetic Aperture Radar (SAR) pulses amplitude for successive elaboration. The AC will be used as a tool of the...
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