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The upcoming availability of new very high resolution SAR imagery from satellite sensors (e.g. Radarsat-2, TerraSAR-X, COSMOSkymed) has renewed interest in extraction of scene parameters for the characterisation of urban areas. In order to properly face this problem, we have defined a structured and hierarchical research strategy that follows a systematic approach to 3-D building characterisation...
Complex SAR image spectral analysis has been shown to provide interesting information about the scattering media, highlighting differences in behavior between homogeneous areas with a fully-developed speckle and point scatterers potentially presenting a more coherent radar spectral response. In the line of previously published works by other groups dealing with coherent scatterers, we have studied...
The separation of transmitter and receiver makes bistatic SAR (synthetic aperture radar) systems preferable to conventional monostatic systems in several applications. However, this separation also leads to difficulties in image processing and in synchronization of the involved systems. For the upcoming hybrid bistatic SAR experiment with the TerraSAR-X satellite as transmitter and the airborne SAR/GMTI...
In this study, we extended the potential of a Content- Based Image Retrieval (CBIR) system based on Self-Organizing Maps (SOMs), for the analysis of remote sensing data. A database was artificially created by splitting each image to be analyzed into small images (or imagelets). Content-based image retrieval was applied to fully polarimetric airborne SAR data, using a selection of polarimetric features...
This paper presents airborne differential SAR results using a stack of 14 images, which were acquired by the experimental SAR (E-SAR) system of the German Aerospace Center during a time span of only two and a half hours. An advanced differential technique is used to retrieve the error in the digital elevation model and the temporal evolution of the deformation for every coherent pixel in the image...
The objective of this paper is to show the potential of multi-polarized mosaic-images from a MAPSAR (L-band) simulation campaign performed in the Amazon region (test site Tapajos) in order to discriminate land use/land cover classes. An Enhanced-Frost filter was used and the thematic discrimination was done by an algorithm for attribute extraction based on Bhattacharya distance. A comparison was made...
This paper presents the top-level design of an airborne, P-band ice sounding radar under development at the Technical University of Denmark. The ice sounder is intended to provide more information on the electromagnetic properties of the Antarctic ice sheet at P-band. A secondary objective is to test new ice sounding techniques, e.g. polarimetry, synthetic aperture processing, and coherent clutter...
Preliminary analyses of the POLSCAT data acquired from the CLPX-II in winter 2006-2007 are described in this paper. The data showed the response of the Ku-band radar echoes to snowpack changes for various types of background vegetation. We observed about 0.4 dB increase in backscatter for every 1 cm SWE accumulation for sage brush and agricultural fields. The data also showed the impact of surface...
Off-shore detection of tsunami waves is a critical component of an effective tsunami warning system (TWS). Even more critical is the off-shore detection of local tsunamis, namely tsunamis that strike coastal areas within minutes from the triggering quake. In this paper we propose a new concept for tsunami detection. NESTRAD (Near-Space Tsunami Radar) consists of a real aperture radar accommodated...
A high-altitude airborne millimeter-wave radar for atmospheric research is being developed by the National Center for Atmospheric Research. The radar will be mounted on the High-Performance Instrumented Airborne Platform for Environmental Research (HIAPER). We present simulations of the minimum detectable signal, the reflectivity accuracy, the polarimetric purity, and the expected accuracy of cloud...
This paper highlights the potential to measure temperate glacier velocities and surface characteristics by airborne interferometric and polarimetric SAR remote sensing. Indeed, a novel SAR airborne campaign took place in October 2006 over two Alpine glaciers. Simultaneously to the acquisition of repeat pass interferometric, polarimetric and multi-band data, in-situ measurements were carried out to...
A bistatic synthetic aperture radar uses a separated transmitter and receiver flying on different platforms to achieve benefits like exploitation of additional information contained in the bistatic reflectivity of targets, reduced vulnerability for military applications, forward looking SAR imaging or increased RCS. A particular constellation, where the transmitter is in space and the receiver near...
L-band Imaging Scatterometer (LIS), developed at NASA/Goddard Space Flight Center as part of the RadSTAR initiative, is an airborne imaging radar that combines phased array technology and digital beam forming techniques for the measurement of important scientific parameters. The instrument operates at 1.26 GHz, horizontal polarization, and employs a real-time processor capable of synthesizing multiple...
Microwave radiometry at low frequencies (L-band, ~ 1.4 GHz) has been known as an optimal solution for remote- sensing of soil moisture. However, the antenna size required to achieve an appropriate resolution from space has limited the development of spaceborne L-band radiometers. This problem can be addressed by interferometric technology called aperture synthesis. The Soil Moisture and Ocean Salinity...
High resolution imaging of the ocean swell was performed using data collected with the polarimetric millimetre wave synthetic aperture radar MEMPHIS. The data, representative for a region off the south Spanish Atlantic coast in spring, have been evaluated using imaging and non-imaging statistical methods. The influence of high resolution processing on the clutter statistics for the Ka- and the W-band...
The interest in bi- and multistatic radar has been growing over the last years as they offer various advantages. For instance the transmitter and receiver can easily be separated and therefore the survivability can be enhanced by deploying the transmitter further away from the scene. Bistatic radar can provide a cost effective solution as the transmitter and receiver can be built without the cost...
This paper presents the analysis of high resolution millimeter SAR clutter data, measured in a joint Swiss-German flight campaign. The generalized Gaussian function and the Kolmogorov-Smirnov test are considered to test the hypothesis of Gaussian clutter process. 35 GHz and 94 GHz data are compared. The results are presented in the time and wavelet domain, as the wavelet domain is an import transform...
Multichannel radar systems are of choice for ground moving target indication (GMTI) since they allow for a joint space-time processing of the received data that enables an efficient suppression of ground clutter returns. The design of the receiving sensor group is driven by the performance specifications of the intended GMTI modus, which usually requires the sensor array to consist of a few hundred...
Applications of small unmanned aerial vehicles (UAVs) have increased steadily over the past years. Applications are found in Earth observation, reconnaissance, monitoring, and surveillance missions using imaging systems. The big advantage of radar sensors is their all-weather capability. Especially imaging radars possess several benefits over optical systems, as they are not affected by rain, snow,...
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