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RTM (~90 m) data and Radarsat-1 images of northern Sudan were processed for exploring potential groundwater accumulation sites in the region. Data analysis unveiled three extensive ancient river courses named as Howar, El-Qaab and Arbain. These eastward flowing rivers, which are now partly hidden beneath the sand, are extinct tributaries of the Nile Valley hydro-system. The main channels of these...
This paper examines the calibration performance of the RADARSAT-1 products since spacecraft commissioning in 1996, and briefly reassesses the calibration ground systems and methodologies in the light of the mission's twelve-year calibration experience and data record. Choices made in the design, deployment and implementation of the RADARSAT-1 calibration plan are retrospectively explored in the context...
Environment Canada's Canadian Ice Service (CIS) is responsible for the daily monitoring of Canadian coastal waters for ice and icebergs, and the presence of oil-based pollution. The routine provision of information on floating ice conditions promotes safe and efficient maritime operations and protects Canada's environment by providing reliable and timely information to marine users in Canadian waters...
This paper presents an overview of various detection and estimation algorithms that have been implemented in the RADARSAT-2 MODEX Processor as well as experimental plans for the validation and demonstration of the space-based GMTI mode. Preliminary RADARSAT-2 GMTI results are also presented.
Polarimetric PALSAR system parameters are assessed using data sets collected over various calibration sites. The data collected over the Amazonian forest permits validating the zero Faraday rotation hypotheses near the equator. The analysis of the Amazonian forest data and the response of the corner reflectors deployed during the PALSAR acquisitions lead to the conclusion that the antenna is highly...
Polarization dependence of L-band measurements over the ocean on surface wind is investigated for the incidence angle ranging from 23 to 25 degrees, by using the Phased-Array L-band Synthetic Aperture Radar (PALSAR) onboard the Advanced Land Observing Satellite (ALOS) and MetOp/ASCAT wind vectors. Polarization ratio (VV/HH) shows clear incidence angle and wind speed dependencies. It increases with...
During 2007 a field experiment was conducted with a goal of optimizing microwave soil moisture retrieval algorithms for small to medium deciduous trees. After initial field checkout in Fall 2006, the ComRAD microwave truck instrument system was deployed to a test site with several stands of deciduous paulownia trees. A joint effort of NASA/GSFC and George Washington University, ComRAD consists of...
Archaeological sites vary greatly in terms of type, size, and material composition. They have in common only that they humanly caused perturbations of what would otherwise be a landscape ordered by natural causes. Protocols are presented in this paper for detecting archaeological sites that can be characterized generally as positive as opposed to normative, in the way that these two terms are used...
Here are presented issues about building or urban area high resolution imaging using synthetic aperture radar (SAR). Promises of circular imaging are assessed. Indeed, this acquisition mode, though available only to airborne sensors, has the potential to solve shadow and overlay problem through rotation of the slantrange projecting direction. It has also an intrinsic elevation dependency that would...
While typical remote sensing imaging instruments produce more and more data, what we miss today are reliable tools for automated information extraction form these images. In the following, we propose a so-called Content Map, a novel Earth Observation value adding product. Basically, it comprises several class files and a viewer showing the different classes of land use and objects contained in the...
Compared to conventional optical images, the classification of remote sensing SAR images represents a rather difficult task. As a rule, the various SAR imaging and product options, the high dynamic range of SAR images, and the presence of speckle noise prevent us from obtaining robust classification results. In the following, we try to circumvent these difficulties by proper pre-processing and despeckling...
The ESA Sentinels constitute the first series of operational satellites responding to the Earth observation needs of the EU-ESA Global Monitoring for Environment and Security (GMES) programme. The GMES space component relies on existing and planned space assets as well as on new complementary developments by ESA. This paper describes the Sentinel-1 mission, an imaging synthetic aperture radar (SAR)...
This paper analyses the SAR response of wetland ecosystems under different environmental conditions and at two different frequencies. We exploited the opportunity of observing the same inundation phenomena by two currently available SAR systems, such as ENVISAT ASAR (C band) and ALOS PALSAR (L band). The results obtained for C band are similar to the ones reported previously in the same area. Increasing...
This work investigates the design of an innovative conical scanning Ku-band (13.4 GHz) scatterometer/radiometer for measuring ocean vector winds. The sensor design is based upon actual measurements obtained by the SeaWinds scatterometer and the Advanced Microwave Scanning Radiometer (AMSR), which operated simultaneously on JAXA's Advanced Earth Observing Satellite-II (ADEOS-II) during 2003. This new...
The Advanced Scatterometer, ASCAT, on MetOp-A was launched on 19 October 2006 as the third wind scatterometer currently in space joining up with the ERS-2 and the SeaWinds scatterometers. Scatterometers measure the radar backscatter from wind-generated cm-size gravity-capillary waves and provide high-resolution wind vector fields over the sea with high quality. In this paper we show progress in high...
The ASCAT, launched on board MetOp-A satellite on October 19th 2006, is a C-band scatterometer operating at 5.255 GHz using fan-beam antennae to measure near surface vector wind over the world's ocean. NOAA produces near-real-time ASCAT wind product at 50 and 25 km resolutions. These wind data are validated against global wind field model and satellite observation from QuikSCAT. The results show ASCAT...
This paper reviews main results from recently published papers and recent research being presented at IGARSS 2008. This work starts with developing and validating a global model, MM5/TBSCAT/F(??), that simulates ground-truth and predicts millimeter-wave radiances consistent with those coincidentally observed by AMSU aboard NOAA satellites. Sensitivity studies of the assumptions in the model further...
Ground-penetrating radar (GPR) has become a useful tool in solving different geophysical tasks in environmental geology, glaciology, archaeology, mineral exploration and the detection of near-surface objects. The large variety of handheld GPR devices, even for harsh field conditions, is an effective tool for surveying small areas. A GPR system installed in a helicopter is an effective method to survey...
SAR-ATI algorithms, which have been developed and validated for airborne SAR data, are now being extended to the RADARSAT-2 Moving Object Detection Experiment (MODEX). Starting from a unified geometry model, specific airborne and spaceborne SAR-ATI features are discussed. Some of the very first MODEX results are presented.
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