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The stable point network (SPN) is a persistent scatterer interferometric technique developed by ALTAMIRA INFORMATION in 2001. The technique makes use of both ERS SAR and/or ASAR differential phase measurements to generate long term terrain movement and precise height maps with the same resolution as the original SAR images. The algorithm is capable to use all the available phase information even in...
A new approach for speckle reduction in SAR images based on the stationary wavelet transform is proposed. Noisy wavelet coefficients are reduced via a shrinkage function that depends on a statistical modeling of the normalized wavelet coefficient probability density functions. Consistencies between coefficients across scales and space are also reinforced using consistency rules. The approach is particularly...
In this paper, an algorithm for unsupervised detection of linear structures, in particular, the geological lineament and shoreline, as seen in Synthetic Aperture Radar (SAR) satellite images is proposed. Methodologies to extract linear features consist of three stages. First, the refined local statistics filter is used to remove the speckle noise on the raw image. The likelihood ratio edge detector...
In remote sensing applications the monitoring of urban areas by means of SAR sensors has been grown to a valuable and indispensable tool. Whereas SAR imaging with a spatial resolution down to one meter is widespread, a resolution down to 10 cm and below is offered only by a very few SAR sensors worldwide. In this contribution the potential of high resolution and very high resolution radar imaging...
With the advent of new, more widely available very high resolution (VHR) SAR and optical sensor satellite constellations, the issue of jointly exploiting the corresponding imaging data in the best possible way naturally arises. Our ultimate goal is the pixel-level fusion of these modalities and their visualization in a 3D context, i.e. draped over terrain data, itself obtained from interferometric...
The main aim of this paper was to explore the potential of SAR data, in combination with optical remote sensing data, in identifying inland fresh water wetland from crop, especially rice paddy. The test area is a part of Hongze Lake, the fourth biggest fresh water lake in China. It is one of important wetlands for migratory birds in China. Due to unreasonable exploitation of wetland resources, the...
The SRAL SAR radar altimeter is the core instrument of the topography mission carried on board the Sentinel-3 satellite which is planned to be launched in 2012. A detailed overview of this instrument is given in this paper in terms of architecture, functions, modes and performances.
This paper introduces an interferometric imaging altimeter system designed for both ocean and land observations. This sensor combines the functions of interferometric radar altimeter and SAR together and is aimed to provide centimeter- level accuracy of topography for ocean and meter-level accuracy of topography for land. With the interferometry technique, a wide swath of 80 km is achieved, and with...
A methodology for change detection of artificial features using multitemporal series of SAR data is presented. The methodology uses time averaging of data from ERS-2 and Envisat yielding improved radiometric quality which highly improves the photointerpretability. The methodology is tested in several scenarios in the context of security applications when data needs to be gathered during cloudy season...
Synthetic aperture radar (SAR) provides a promising method for offshore wind field estimation, particularly in the context of important for offshore wind farm development. This paper introduces an iterative maximum aposteriori probability (MAP) method for combining meteorological model output with synthetic aperture radar for offshore wind field estimation. The MAP approach is demonstrated for 40...
A 6-parameter frequency spectrum with two peaks and a cos-2s type spreading function is used to simulate the mixed waves. The spaceborne and airborne synthetic aperture radar (SAR) image cross spectra of mixed waves in different significant wave height, wave length, wave direction and wave component are then calculated by using Engen's nonlinear transformation formula. Analysis based on above simulation...
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 improved ground resolution of state-of-the-art synthetic aperture radar (SAR) sensors suggests utilizing SAR data for the analysis of urban areas. Even in the case of InSAR, for building recognition usually the analysis is triggered mainly from features detected in the magnitude images. However, considering InSAR data significant phase profiles in range direction at building locations are observable...
In February 2007 the German TerraSAR-X satellite will be launched and the TerraSAR-X mission will enter its approximately 5 months commissioning phase. At that time, the challenging developments on both sides, the advanced high- resolution multi-mode SAR instrument on the one hand and the corresponding sophisticated TerraSAR-X ground segment on the other hand will prove correct interaction and functioning...
TerraSAR-X is Germany's first national remote sensing satellite being implemented in a public-private partnership between the German Aerospace Centre (DLR) and EADS Astrium GmbH, with a significant financial contribution from the industrial partner. This radar satellite, which is to be launched in June 2007 will supply high-quality radar data for purposes of scientific observation of the Earth for...
Currently the European satellites ERS-2 and ENVISAT are flying on the same orbit with a time separation of 30 minutes. In this presentation pairs of the respective synthetic aperture radar data are analyzed with respect to different atmospheric and oceanic processes. The presented results were obtained in the framework of the ESA AO project COTAR. The tandem configuration exists since the launch of...
Land surface process modelling might be limited due to lack of reliable model input data. Key surface variables as land cover information or soil moisture conditions have been proven to be observable by remote sensing systems. The integration of remote sensing data into land surface process models might therefore help to improve their simulations results. Longer wavelength SAR data has a higher sensitivity...
A concept for classifying multisensor data sets, consisting of multispectral and SAR imagery is introduced. Each data source is separately classified by a support vector machine (SVM). In a decision fusion the outputs of the preliminary SVMs are used to determine the final class memberships. This fusion is performed by another SVM as well as two common voting schemes. The results are compared with...
Radar backscattered signals over the ocean are dampened in extremely high winds, which leads to a wind speed ambiguity problem during the process of wind retrieval from synthetic aperture radar (SAR). This problem was firstly studied by Shen et al. (2007), where we proposed a wind speed ambiguity removal scheme for the two wind speed solutions that may exist for any given normalized radar cross section...
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