References of "De Rauw, Dominique"
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See detailEmpirical Removal of Tides and Inverse Barometer Effect on DInSAR From Double DInSAR and a Regional Climate Model
Glaude, Quentin ULiege; Amory, Charles ULiege; Berger, Sophie et al

in IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing (2020), 13

Ice shelves—the floating extensions of the Antarctic ice sheet—regulate the Antarctic contribution to sea-level rise by restraining the grounded ice flowing from upstream. Therefore, ice-shelf change (e.g ... [more ▼]

Ice shelves—the floating extensions of the Antarctic ice sheet—regulate the Antarctic contribution to sea-level rise by restraining the grounded ice flowing from upstream. Therefore, ice-shelf change (e.g., ice-shelf thinning) results in accelerated ice discharge into the ocean, which has a direct effect on sea level. Studying ice-shelf velocity allows the monitoring of the ice shelves’ stability and evolution. Differential synthetic aperture radar interferometry (DInSAR) is a common technique from which highly accurate velocity maps can be inferred at high resolution. Because ice shelves are afloat, small sea-level changes—i.e., ocean tides and varying atmospheric pressure (aka inverse barometer effect) lead to vertical displacements. If not accounted for in the interferometric process, these effects will induce a strong bias in the horizontal velocity estimation. In this article, we present an empirical DInSAR correction technique from geophysical models and double DInSAR, with a study on its variance propagation. The method is developed to be used at large coverage on short timescales, essential for the near-continuous monitoring of rapidly changing areas on polar ice sheets. We used Sentinel-1 SAR acquisitions in interferometric wide and extra -wide swath modes. The vertical interferometric bias is estimated using a regional climate model (MAR) and a tide model (CATS2008). The study area is located on the Roi Baudouin Ice Shelf in Dronning Maud Land, East Antarctica. Results show a major decrease (67 m ⋅ a −1 ) in the vertical-induced displacement bias. [less ▲]

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See detailMUZUBI – Advanced phase unwrapping using split-band interferometry
Defrere, Denis ULiege; Radioti, Aikaterini ULiege; De Rauw, Dominique ULiege et al

Scientific conference (2019, November 28)

Absolute phase retrieval is a mandatory pre-requisite for accurate topographic measurements from SAR interferometric data. Because they use the phase of a starting point as a reference level, classical ... [more ▼]

Absolute phase retrieval is a mandatory pre-requisite for accurate topographic measurements from SAR interferometric data. Because they use the phase of a starting point as a reference level, classical phase unwrapping techniques usually fail to connect regions separated by non-coherent areas and require additional corrections to produce continuous phase maps which are consistent with the ground truth. A technique commonly used for that purpose is split-band interferometry, also known as multi chromatic analysis (MCA), which exploits the large range bandwidth of SAR sensors such as TerraSAR-X / TanDEM-X. The idea behind this technique is that the absolute phase is proportional to the intercept and slope of the spectrally-dispersed phase across individual sub-bands. Previous MCA analysis generally focused on the search of carefully-chosen targets, called frequency-persistent scatterers, which are used to estimate the global phase offset of the entire disconnected region. In this study, we take another approach and argue that all pixels in each independently-unwrapped region carry useful information that can be used to improve the precision on the absolute phase. In the context of the MUZUBI project, we have applied this idea to TerraSAR-X / TanDEM-X and SENTINEL images and investigated the effect of sensor bandwidth, mean coherence across the region, and region size on the precision of the computed absolute phase. [less ▲]

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See detailFundamental Limit of Absolute Phase Retrieval with Split-Band Interferometry: Application to TerraSAR-X / TanDEM-X and SENTINEL Images
Defrere, Denis ULiege; Radioti, Aikaterini ULiege; Libert, Ludivine et al

Scientific conference (2019, October 24)

Accurate topographic and deformation measurements from SAR interferometry require to correctly unwrap the phase. However, classical phase unwrapping often fails at connecting different regions separated ... [more ▼]

Accurate topographic and deformation measurements from SAR interferometry require to correctly unwrap the phase. However, classical phase unwrapping often fails at connecting different regions separated by low coherence. This results in phase jumps, difficult to correct or even detect without proper ground measurements. One solution consists in using the topographic and deformation phase dependence with the wavelength. Using large bandwidth SAR acquisitions such as TerraSAR-X Spotlight images, we can apply split-band interferometry (SBInSAR) in order to produce different interferograms with slightly different center-frequencies. The absolute topographic phase is then proportional to the slope of individuals split-band interferograms. Previous MCA analysis generally focused on the search of carefully-chosen targets, called frequency-persistent scatterers (PSf). If they exist, these PSfs could be used to estimate the global phase offset of the entire disconnected region. Here, we take another approach and argue that all pixels in each independently-unwrapped region carry useful information on the absolute phase. All this information can finally be used to improve the precision on the absolute phase. In the context of the MUZUBI project, we have applied this idea to TerraSAR-X / TanDEM-X, CSK, and SENTINEL images. We investigated the effect of sensor bandwidth, mean coherence across the region, and region size on the precision of the computed absolute phase. The technique is also compared with the results of the SRTM digital elevation model. In the end, we derived the fundamental limits of applicability of split-band interferometry. [less ▲]

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See detailSplit-band SAR Interferometry For Vessel Tracking: Application On Sentinel-1 Data
Kirkove, Murielle ULiege; De Rauw, Dominique ULiege; Orban, Anne ULiege

Poster (2019, May 15)

Most recent Synthetic Aperture Radar (SAR) sensors use wide band signals to achieve metric range resolution. One can take advantage of this wide band to split a single acquisition into sub-bands and ... [more ▼]

Most recent Synthetic Aperture Radar (SAR) sensors use wide band signals to achieve metric range resolution. One can take advantage of this wide band to split a single acquisition into sub-bands and generate several lower-resolution images, centered on slightly different frequencies, performing so a SAR spectral analysis. One application of this process is the vessel detection based on spectral coherence analysis. We present a processing technique of vessel detection using SAR data, combining spectral coherence processing and Constant False Alarm Rate (CFAR) algorithm. The control of open seas areas or marine protected areas (MPAs) is usually performed based on the Automated Identification System (AIS) embarked within most of the vessels. The proposed technique handles a comparison with AIS data allowing to determine the ratio of non-cooperative vessels (or not equipped with AIS) within an area. We performed experiments on SAR data acquired on the Libyan Sea and we compared the results with the ones obtained by the SNAP “Ocean feature” tool, commonly used by the Remote Sensing community. [less ▲]

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See detailOn the characterization of frequency-persistent scatterers in Split-Band Interferometry
Libert, Ludivine ULiege; De Rauw, Dominique ULiege; d'Oreye, Nicolas et al

Conference (2018, July 24)

Split-Band Interferometry (SBInSAR) requires the presence of reliable frequency-persistent scatterers within the studied scene. However, the physical nature of such reflectors is still poorly known. In ... [more ▼]

Split-Band Interferometry (SBInSAR) requires the presence of reliable frequency-persistent scatterers within the studied scene. However, the physical nature of such reflectors is still poorly known. In this work, we perform a temporal analysis over the region of the Virunga Volcanic Province (Democratic Republic of Congo - DRC) and we show that frequency-persistent scatterers are not necessarily stable over time. We study and quantify the effect of the range resolution loss due to the bandwidth degradation in the SBInSAR process. Finally, radiometric information and spectral coherence are used to show that frequency-persistent scatterers cannot be associated to a specific scattering mechanism. [less ▲]

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See detailSplit-Band SAR and Split Band InSAR principle and applications
De Rauw, Dominique ULiege; Kirkove, Murielle ULiege; Libert, Ludivine ULiege et al

Poster (2018, April 19)

Most recent SAR sensors use wide band signals to achieve metric range resolution. One can also take advantage of wide band to split it into sub-bands and generate several lower-resolution images, centered ... [more ▼]

Most recent SAR sensors use wide band signals to achieve metric range resolution. One can also take advantage of wide band to split it into sub-bands and generate several lower-resolution images, centered on slightly different frequencies, from a single acquisition (Bovenga & al. 2014). This process, named Multi Chromatic Analysis (MCA) corresponds to performing a spectral analysis of SAR images. From this spectral analysis, three potential applications are shown. First, this splitting allows performing a spectral analysis of observed scatterers. Spectral coherence is derived by computing the coherence between sub-images issued from a single SAR acquisition. It was shown that in the presence of a random distribution of surface scatterers, spectral coherence is proportional to sub-band intersection of sub-images. This model is fully verified when observing spectral coherence on open seas areas. If the scatterers distribution departs from this distribution, like for manmade structures, spectral coherence may be preserved to a certain degree and allows discriminating vessels from see clutter even in case of high sea state. This property can be used to perform vessel detection (Derauw & al., 2010). Second, Split-Band SAR interferometry (SBInSAR) is also based on this spectral analysis performed on each image of an InSAR pair, yielding a stack of sub-band interferograms. Scatterers keeping a coherent behaviour in each sub- band interferogram show a phase that varies linearly with the carrier frequency, the slope being proportional to the absolute optical path difference. This potentially solves the problems of phase unwrapping on a pixel-per-pixel basis (Libert & al.). Third, unwrapping classically two sub-band interferograms allows getting two phases of a same scene and same ionospheric components. Since these two components behave differently with frequency, SBInSAR allows discriminating both and remove the ionospheric artifacts if presents (Gomba & al. 2016, Furuya & al. 2016). [less ▲]

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See detailOptimum split-band parameters for phase offset retrieval
Libert, Ludivine ULiege; De Rauw, Dominique ULiege; Barbier, Christian ULiege

in IEEE International Geoscience and Remote Sensing Symposium (2017, December 04)

The potential of Split-Band processing to determine the absolute phase of an interferometric pair of SAR images has been demonstrated in previous studies. In this work we propose a new approach based on ... [more ▼]

The potential of Split-Band processing to determine the absolute phase of an interferometric pair of SAR images has been demonstrated in previous studies. In this work we propose a new approach based on the joint use of Split-Band Interferometry and SAR Interferometry for the phase leveling of disconnected regions of an unwrapped interferogram. In this paper a new selector of frequency-persistent scatterers is presented. In order to demonstrate the applicability of the method we propose an artificial disconnection of the regions to validate our results without any ground based measurements. The presented method is tested on TerraSAR-X images acquired with a range bandwidth of 150 MHz over the Nyamuragira volcano in the African region of the Kivu Rift. Several combinations of split parameters are applied and investigated to determine the best configuration for this application. [less ▲]

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See detailDevelopment of an Interferometric Mass Processing Chain for Multitemporal Ground Deformation Measurements
Libert, Ludivine ULiege; De Rauw, Dominique ULiege; d'Oreye, Nicolas

Conference (2017, November 07)

The main goal of the RESIST project is to understand the mechanisms driving volcanic eruptions and landslides in the Kivu region, on the East African Rift. In order to model both volcanic and landslide ... [more ▼]

The main goal of the RESIST project is to understand the mechanisms driving volcanic eruptions and landslides in the Kivu region, on the East African Rift. In order to model both volcanic and landslide processes, it is necessary to measure ground deformations in the region accurately. For this purpose, both ground-based instruments (e.g. GPS network) and spaceborne data (e.g. optical and SAR images) are used. One aspect of the project focuses on Differential SAR Interferometry (DInSAR), which is a technique used to map ground deformations occurring between two SAR images acquired at different times. It is today a well-mastered technique that offers large spatial coverage with a typical temporal sampling of one to several days, depending on the chosen sensor. In the last years, multitemporal approaches based on DInSAR have been developed, like the Small BAseline Subset (SBAS) [1] and Multidimensional Small BAseline Subset (MSBAS) [2] techniques, or the Persistent Scatterers Interferometry (PSI) [3]. In the framework of RESIST, we use MSBAS to perform ground deformations monitoring along time. The Multidimensional Small BAseline Subset (MSBAS) technique produces 2-D time series of ground deformations by integrating data sets of SAR images acquired by different sensors, with different spatial and temporal sampling, resolutions, incidence angles, wavelengths, pass directions and other varying parameters. By combining at least two data sets with overlapping spatial and temporal coverage and an extended range of look angles, the evolution of deformations in the vertical and west-east directions can be computed by the MSBAS approach [2]. The MSBAS software feeds on a large amount of deformation maps, which are produce by DInSAR. Such an amount of data cannot be produced by hand and that is the reason why we developed an automatic interferometric processing chain meant to produce large amounts of products adequate for multitemporal methods like MSBAS. The interferometric processing is supported by the CSL InSAR Suite (CIS) software developed at Centre Spatial de Liège, which presents the advantages to be fully adaptable to the needs of the MSBAS technique and the thematic specificities. Indeed, numerous options (e.g. adaptive filtering, wide swath interferometry) have been added to the CIS software in the framework of the RESIST project. In a first time, we will briefly present the MSBAS approach and its advantages regarding the ground deformation measurements. In the second part of the presentation, we will introduce the mass processing chain step by step and its functionalities. Critical steps of the chain, like the chosen strategy for the interferometric pairs selection, the integration of Sentinel-1 data or the image interpolation approach, will be presented in more details. Finally, preliminary results of an MSBAS processing over the Bukavu area will be presented. REFERENCES: [1] Berardino, P., Fornaro, G., Lanari, R., and Sansosti, E. (2002). A new algorithm for surface deformation monitoring based on small baseline differential SAR interferograms, IEEE Trans. Geosci. Remote Sens., 40, 11, pp. 2375-2383. doi: 10.1109/TGRS.2002.803792. [2] Samsonov, S., and d’Oreye, N. (2012). Multidimensional time series analysis of ground deformation from multiple InSAR data sets applied to Virunga Volcanic Province, Geophysical Journal International, 191, 3, pp. 1095-1108. doi: 10.1111/j.1365-246X.2012.05669.x [3] Ferretti, A., Prati, C., and Rocca, F. (2001). Permanent scatterers in SAR interferometry, IEEE Trans. Geosci. Remote Sens., 39, 1, pp. 8-20. doi: 10.1109/36.898661. [less ▲]

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See detailSplit-Band Interferometry-Assisted Phase Unwrapping for the Phase Ambiguities Correction
Libert, Ludivine ULiege; De Rauw, Dominique ULiege; d'Oreye, Nicolas et al

in Remote Sensing (2017), 9(9),

Split-Band Interferometry (SBInSAR) exploits the large range bandwidth of the new generation of synthetic aperture radar (SAR) sensors to process images at subrange bandwidth. Its application to an ... [more ▼]

Split-Band Interferometry (SBInSAR) exploits the large range bandwidth of the new generation of synthetic aperture radar (SAR) sensors to process images at subrange bandwidth. Its application to an interferometric pair leads to several lower resolution interferograms of the same scene with slightly shifted central frequencies. When SBInSAR is applied to frequency-persistent scatterers, the linear trend of the phase through the stack of interferograms can be used to perform absolute and spatially independent phase unwrapping. While the height computation has been the main concern of studies on SBInSAR so far, we propose instead to use it to assist conventional phase unwrapping. During phase unwrapping, phase ambiguities are introduced when parts of the interferogram are separately unwrapped. The proposed method reduces the phase ambiguities so that the phase can be connected between separately unwrapped regions. The approach is tested on a pair of TerraSAR-X spotlight images of Copahue volcano, Argentina. In this framework, we propose two new criteria for the frequency-persistent scatterers detection, based respectively on the standard deviation of the slope of the linear regression and on the phase variance stability, and we compare them to the multifrequency phase error. Both new criteria appear to be more suited to our approach than the multifrequency phase error. We validate the SBInSAR-assisted phase unwrapping method by artificially splitting a continuous phase region into disconnected subzones. Despite the decorrelation and the steep topography affecting the volcanic test region, the expected phase ambiguities are successfully recovered whatever the chosen criterion to detect the frequency-persistent scatterers. Comparing the aspect ratio of the distributions of the computed phase ambiguities, the analysis shows that the phase variance stability is the most efficient criterion to select stable targets and the slope standard deviation gives satisfactory results. [less ▲]

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See detailThe Split-Band Interferometry Approach to Determine the Phase Unwrapping Offset
Libert, Ludivine ULiege; De Rauw, Dominique ULiege; d'Oreye, Nicolas et al

Poster (2017, June)

This poster presents an approach based on the Split-Band Interferometry to solve the ambiguities introduced during the phase unwrapping of separate regions.

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See detailA step-by-step recipe of band-spli3ng technique for isola8on of ionospheric signal in L-band InSAR data
Furuya, Masato; Suzuki, Takato; De Rauw, Dominique ULiege

Poster (2016, December 15)

Ionospheric signals are widely regarded as nuisance in low- frequency InSAR data, and thus a variety of correction techniques have been proposed. Although band-splitng of range spectrum has been shown to ... [more ▼]

Ionospheric signals are widely regarded as nuisance in low- frequency InSAR data, and thus a variety of correction techniques have been proposed. Although band-splitng of range spectrum has been shown to be effectve (Brcic et al., 2010; Rosen et al., 2010; Gomba et al., 2015), the band- spliting technique seems to have not been widely used. Whereas this would be partly because the impacts of ionosphere on InSAR data are not necessarily serious, we consider that this could be also because the details of the technique have not been reproducibly shown. Here we show our step-by-step recipe of the band-spliting technique, and demonstrate two case studies that reveal the effectiveness of the technique. [less ▲]

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See detailA TOPSAR Processor based on the Omega-K Algorithm: Evaluation with Sentinel-1 Data
Kirkove, Murielle ULiege; Orban, Anne ULiege; De Rauw, Dominique ULiege et al

in A TOPSAR Processor based on the Omega-K Algorithm: Evaluation with Sentinel-1 Data (2016, June)

This paper presents a processor for the TOPS (Terrain Observation by Progressive Scans) imaging mode. TOPS signals have two characteristics that make the use of Stripmap SAR processors inconvenient, i.e ... [more ▼]

This paper presents a processor for the TOPS (Terrain Observation by Progressive Scans) imaging mode. TOPS signals have two characteristics that make the use of Stripmap SAR processors inconvenient, i.e., azimuth frequency and azimuth time foldings. This paper describes a processor based on the Omega-K (Ω-k) algorithm, combined with pre-processing by frequency unfolding and post-processing by time unfolding. Raw data acquired by Sentinel-1 have been used to assess the quality of image reconstruction [less ▲]

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See detailThe RESIST Project: a Study of Geohazards in the Kivu Basin Region using ground- and space borne Techniques
Libert, Ludivine ULiege; d'Oreye, Nicolas; Kervyn, François et al

Poster (2015, September)

Presentation of the goals and means of the RESIST project

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See detailSplit-Band Interferometric SAR Processing Using TanDEM-X Data
De Rauw, Dominique ULiege; Kervyn, François; d'Oreye, Nicolas et al

in ESA SP-731 (2015, March)

Most recent SAR sensors use wide band signals to achieve metric range resolution. One can also take advantage of wide band to split it into sub-bands and generate several lower-resolution images, centered ... [more ▼]

Most recent SAR sensors use wide band signals to achieve metric range resolution. One can also take advantage of wide band to split it into sub-bands and generate several lower-resolution images, centered on slightly different frequencies, from a single acquisition. This process, named Multi Chromatic Analysis (MCA) corresponds to performing a spectral analysis of SAR images. Split-Band SAR interferometry (SBInSAR) is based on spectral analysis performed on each image of an InSAR pair, yielding a stack of sub-band interferograms. Scatterers keeping a coherent behaviour in each sub-band interferogram show a phase that varies linearly with the carrier frequency, the slope being proportional to the absolute optical path difference. This potentially solves the problems of phase unwrapping on a pixel-per-pixel basis. In this paper, we present an SBInSAR processor and its application using TanDEM-X data over the Nyiragongo volcano. [less ▲]

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See detailSpectral coherence applied to vessel tracking
De Rauw, Dominique ULiege; Barbier, Christian ULiege

in Radar, IEEE International Conference (2014, October)

Multi-Chromatic or spectral Analysis (MCA) of SAR images consists in splitting wide band SAR signals into sub-bands to generate several lower resolution images from a single acquisition. This splitting ... [more ▼]

Multi-Chromatic or spectral Analysis (MCA) of SAR images consists in splitting wide band SAR signals into sub-bands to generate several lower resolution images from a single acquisition. This splitting allows performing a spectral analysis of observed scatterers. Spectral coherence is derived by computing the coherence between sub-images issued from a single SAR acquisition. It was shown that in the presence of a random distribution of surface scatterers, spectral coherence is proportional to sub-band intersection of sub-images. This model is fully verified when observing spectral coherence on open seas areas. If the scatterers distribution departs from this distribution, like for manmade structures, spectral coherence may be preserved to a certain degree. We investigated the spectral coherence to perform vessel detection on a sea background by using spotlight images acquired on the Venice Lagoon. Sea background tends to lead to very low spectral coherence while this latter is preserved on the targeted vessels, even for very small ones. A first analysis shows that all vessels observable in intensity images are easily detected in the spectral coherence images which can be used as a complementary information channel to constrain vessel detection. [less ▲]

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See detailMulti-Chromatic Analysis of SAR Images for Coherent Target Detection
Bovenga, Fabio; Barbier, Christian ULiege; De Rauw, Dominique ULiege et al

in Remote Sensing (2014), 6

This work investigates the possibility of performing target analysis through the Multi-Chromatic Analysis (MCA), a technique that basically explores the information content of sub-band images obtained by ... [more ▼]

This work investigates the possibility of performing target analysis through the Multi-Chromatic Analysis (MCA), a technique that basically explores the information content of sub-band images obtained by processing portions of the range spectrum of a synthetic aperture radar (SAR) image. According to the behavior of the SAR signal at the different sub-bands, MCA allows target classification. Two strategies have been experimented by processing TerraSAR-X images acquired over the Venice Lagoon, Italy: one exploiting the phase of interferometric sub-band pairs, the other using the spectral coherence derived by computing the coherence between sub-band images of a single SAR acquisition. The first approach introduces the concept of frequency-persistent scatterers (FPS), which is complementary to that of the time-persistent scatterers (PS). FPS and PS populations have been derived and analyzed to evaluate the respective characteristics and the physical nature of the targets. Spectral coherence analysis has been applied to vessel detection, according to the property that, in presence of a random distribution of surface scatterers, as for open sea surfaces, spectral coherence is expected to be proportional to sub-band intersection, while in presence of manmade structures it is preserved anyhow. First results show that spectral coherence is well preserved even for very small vessels, and can be used as a complementary information channel to constrain vessel detection in addition to classical Constant False Alarm Rate techniques based on the sole intensity channel. [less ▲]

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See detailStudy of a Passive Companion Micro-Satellite to the SAOCOM-1B Satellite of Argentina, for Bistatic and Interferometric SAR Applications
Barbier, Christian ULiege; De Rauw, Dominique ULiege; Orban, Anne ULiege et al

in Spie (Ed.) Proceedings SPIE Remote Sensing Conference 9241 Sensors, Systems, and Next-Generation Satellites (2014, September)

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See detailDetermining Tree Height by Polarimetric SAR Interferometry: Methodology
Orban, Anne ULiege; Barbier, Christian ULiege; De Rauw, Dominique ULiege

Poster (2012, September)

This poster presents the development of tools for extraction of tree height estimates from SARAT data using polarimetric SAR interferometry (PolInSAR) techniques: theoretical and practical expertise in ... [more ▼]

This poster presents the development of tools for extraction of tree height estimates from SARAT data using polarimetric SAR interferometry (PolInSAR) techniques: theoretical and practical expertise in canopy height extraction using advanced PolInSAR techniques, PolInSAR tool tailored to SAOCOM and SARAT specificities allowing these estimates to be made, and finally PolInSAR products and canopy height estimates over the test site of interest. [less ▲]

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See detailWide band SAR sub-band splitting and inter-band coherence measurements
De Rauw, Dominique ULiege; Orban, Anne ULiege; Barbier, Christian ULiege

in Remote Sensing Letters (2010), 1(3), 133-140

Range resolution of SAR images is determined by transmitted radar signal bandwidth. Most recent SAR sensors use wide band signals in order to achieve metric range resolution, whereas metric azimuth ... [more ▼]

Range resolution of SAR images is determined by transmitted radar signal bandwidth. Most recent SAR sensors use wide band signals in order to achieve metric range resolution, whereas metric azimuth resolution can be achieved in spotlight mode. As an example, ENVISAT ASAR sensor uses a 15-MHz bandwidth chirp whereas TerraSAR-X spotlight mode uses signals having a 150-MHz bandwidth leading to a potentially 10 times higher resolution. One can also take advantage of wide band to split the full band into sub-bands and generate several lower resolution images from a single acquisition, each being centred on slightly different frequencies. These sub-images can then be used in a classical interferometric process to measure inter-band coherence of a given scene. This inter-band coherence reveals scatterers keeping a stable-phase behaviour along with frequency shift. A simple coherence model derived from Zebker model for randomly distributed surface scatterers is proposed. Examples are presented, showing that scatterers can have a behaviour that deviates from the model, leading to a new information channel. [less ▲]

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See detailAlignement et optimisation d'un simulateur solaire d'une configuration de 1SC à une configuration à 10SC.
De Rauw, Dominique ULiege; Mazy, Emmanuel ULiege; Stockman, Yvan ULiege et al

Conference (2009, November 18)

Ce papier décrit les tâches réalisées dans le cadre d’un projet de modification du simulateur solaire de l’ESA afin de l’adapter et le faire passer d’une configuration où le flux est de une constante ... [more ▼]

Ce papier décrit les tâches réalisées dans le cadre d’un projet de modification du simulateur solaire de l’ESA afin de l’adapter et le faire passer d’une configuration où le flux est de une constante solaire vers une configuration à 10 constantes solaires. Nous exposons les tâches réalisées par le Centre Spatial de Liège en ce qui concerne la modélisation et la simulation des configurations ainsi que les éléments mis au point pour l’alignement des miroirs du simulateur solaire et pour la mesure d’uniformité de flux. [less ▲]

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