Kleine I.,German Research Center for Geosciences |
Rogass C.,German Research Center for Geosciences |
Medeiros P.H.A.,Instituto Federal Do Ceara IFCE |
Meyer Zu Erpen N.,Astrium GEO Information Services |
And 3 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013
The semi-arid Northeast of Brazil is characterized by distinct rainy and dry seasons. The water supply for the local population is based on surface reservoirs in which precipitation is collected. There are more than 150 reservoirs in the 933 km2 Benguê catchment, however, little is known about the temporal dynamics of the water storage in the reservoirs. In this study, we use TerraSAR-X imagery for a year-long monitoring of reservoir surface areas and their seasonal changes. The precise extraction of the reservoir surface areas forms the basis of the monitoring. Therefore, we evaluated the results of a pixel-based threshold classification and a feature-based segmentation (mean shift). The evaluation was based on in-situ GPS measurements and manual digitization. The results of the manual digitization and threshold classification were similar as both tended to underestimate the water surface area in comparison to GPS in-situ data. The mean shift segmentation, however, tended to spread over the shorelines into the surrounding areas. We used the threshold classification for the analysis of 47 TerraSAR-X images. The viewing direction of the TerraSAR-X sensor was also important for the distinction of the entire area of the reservoirs, since geometric effects at the shorelines shaded parts of the water surface area. For the monitoring of the reservoir area with only one viewing direction we derived an empirical geometry correction factor. © 2013 SPIE.
Saur G.,Fraunhofer Institute for Optronics, System Technologies and Image Exploitation |
Estable S.,Airbus |
Zielinski K.,Airbus |
Knabe S.,Astrium GEO Information Services |
And 2 more authors.
OCEANS 2011 IEEE - Spain | Year: 2011
The project DEKO (Detection of artificial objects in sea areas) is integrated in the German DeMarine-Security project and focuses on the detection and classification of ships and offshore artificial objects relying on TerraSAR-X as well as on RapidEye multispectral optical images. The objectives are 1/ the development of reliable detection algorithms and 2/ the definition of effective, customized service concepts. In addition to an earlier publication, we describe in the following paper some selected results of our work. The algorithms for TerraSAR-X have been extended to a processing chain including all needed steps for ship detection and ship signature analysis, with an emphasis on object segmentation. For Rapid Eye imagery, a ship detection algorithm has been developed. Finally, some applications are described: Ship monitoring in the Strait of Dover based on TerraSAR-X StripMap using AIS information for verification, analyzing TerraSAR-X HighResolution scenes of an industrial harbor and finally an example of surveying a wind farm using change detection. © 2011 IEEE.
Koppe W.,Astrium GEO Information Services |
Koppe W.,University of Cologne |
Gnyp M.L.,University of Cologne |
Hennig S.D.,Astrium GEO Information Services |
And 6 more authors.
Photogrammetrie, Fernerkundung, Geoinformation | Year: 2012
This paper illustrates the results obtained in the frame of experimental campaigns carried out on winter wheat fields in the North China Plain from March 2006 to June 2007. Investigations focused on the methodology of estimating biomass on a regional scale with hyperspectral (EO-1 Hyperion) and microwave data (Envisat ASAR). Special importance is drawn to the combined analysis of microwave and optical satellite data for crop monitoring. Since hyperspectral and synthetic aperture radar (SAR) sensors respond to crop characteristics differently, their complementary information content can support the estimation of crop conditions. During the regular field measurements, satellite data from jointing to ripening stages were acquired. Linear regression models between measured surface reflection as well as surface backscatter and wheat's standing biomass were established. For hyperspectral data, the normalized ratio index (NRI) based on 825 nm and 1225 nm wavebands was calculated from 2006 data as input for the regression model. In addition, Envisat ASAR VV polarization data were related to winter wheat crop parameters. Bivariate correlation results from this study indicate that both multi-temporal EO-1 Hyperion as well as Envisat ASAR data provide notable relationships with crop conditions. As expected, linear correlation of hyperspectral data performed slightly better for biomass estimation (R 2 = 0.83) than microwave data (R 2 = 0.75) for the 2006 field survey. Based on the results, hyperspectral Hyperion data seem to be more sensitive to crop conditions. Improvements for crop parameter estimation were achieved by combining hyperspectral indices and microwave backscatter into a multiple regression analysis as a function of crop parameters. Combined analysis was performed for biomass estimation (R 2 = 0.90) with notable improvements in prediction power. © 2012 E. Schweizerbart'sche Ve rlagsbuchhandlung.
Schlund M.,Astrium GEO Information Services |
Schlund M.,Friedrich - Schiller University of Jena |
von Poncet F.,Astrium GEO Information Services |
Hoekman D.H.,Wageningen University |
And 2 more authors.
Remote Sensing of Environment | Year: 2014
Deforestation and forest degradation are one of the important sources for human induced carbon dioxide emissions and their rates are highest in tropical forests. For man-kind, it is of great importance to track land-use conversions like deforestation, e.g. for sustainable forest management and land use planning, for carbon balancing and to support the implementation of international initiatives like REDD. + (Reducing Emissions from Deforestation and Degradation). SAR (synthetic aperture radar) sensors are suitable to reliably and frequently monitor tropical forests due to their weather independence. The TanDEM-X mission (which is mainly aimed to create a unique global high resolution digital elevation model) currently operates two X-band SAR satellites, acquiring interferometric SAR data for the Earth's entire land surface multiple times. The operational mission provides interferometric data as well as mono- and bistatic scattering coefficients. These datasets are homogenous, globally consistent and are acquired in high spatial resolution. Hence, they may offer a unique basic dataset which could be useful in land cover monitoring.Based on first datasets available from the TanDEM-X mission, the main goal of this research is to investigate the information content of TanDEM-X data for mapping forests and other land cover classes in a tropical peatland area. More specifically, the study explores the utility of bistatic features for distinguishing between open and closed forest canopies, which is of relevance in the context of deforestation and forest degradation monitoring. To assess the predominant information content of TanDEM-X data, the importance of information derived from the bistatic system is compared against the monostatic case, usually available from SAR systems. The usefulness of the TanDEM-X mission data, i.e. scattering coefficients, derived textural information and interferometric coherence is investigated via a feature selection process. The resulting optimal feature sets representing a monostatic and a bistatic SAR dataset were used in a subsequent classification to assess the added value of the bistatic TanDEM-X features in the separability of land cover classes. The results obtained indicated that especially the interferometric coherence significantly improved the separability of thematic classes compared to a dataset of monostatic acquisition. The bistatic coherence was mainly governed by volume decorrelation of forest canopy constituents and carries information about the canopy structure which is related to canopy cover. In contrast, the bistatic scattering coefficient had no significant contribution to class separability. The classification with coherence and textural information outperformed the classification with the monostatic scattering coefficient and texture by more than 10% and achieved an overall accuracy of 85%. These results indicate that TanDEM-X can serve as a valuable and consistent source for mapping and monitoring tropical forests. © 2013 Elsevier Inc.
Gabriel-Robez C.,Astrium GEO Information Services
32nd Asian Conference on Remote Sensing 2011, ACRS 2011 | Year: 2011
With four new optical imaging satellites to launch over the next three years, Astrium GEO-Information Services is gearing up to bring its customers the best that space technology has to offer, ensuring continuity of service up to 2023. The Pléiades twins are very-high-resolution satellites delivering 50-cm ortho color products as a standard. The other two are SPOT 6 and 7, designed to extend SPOT 5's success to the 1.5-m product family. Phased on the same orbit, the constellation will enjoy unprecedented reactivity, with intra-day revisit capacity anywhere on the Earth. Multiple tasking plans per day result in an unrivalled optimization of data collection: unforeseen weather changes, as well as last-minute requests, can be taken into account for a first-class level of service. Furthermore, the upcoming constellation enjoys an unheard-of commercial availability. SPOT 6 and 7 are perfectly suited for any kind of application requiring broad coverage (60-km swath at nadir), whereas Pléiades affords the largest swath in the sub-metric market (20 km at nadir), ensuring all users maximized coverage as well as easier data processing and handling. All satellites are equipped with CMGs for state-of-the-art agility, enabling more simultaneous requests to be satisfied on the same pass. With an effective acquisition capacity reaching more than 6 million square kilometers per day for the four-satellite constellation, Astrium GEO-Information Services is more than ever committed to delivering data. The consecutive launches of Pléiades 1 & 2 and SPOT 6 & 7 signal a paradigm shift for Astrium GEO-Information Services. Ready to enter the very-high-resolution market, the company is enhancing its role as a multisensor distributor operating a coherent, optimized multi-resolution constellation to serve applications such as defense, civil protection, hazard management, urban or national mapping, agriculture, and network and infrastructure management.
Tinel C.,French National Center for Space Studies |
Fontannaz D.,French National Center for Space Studies |
Montfort B.,Astrium GEO Information Services |
De Boissezon H.,French National Center for Space Studies
International Geoscience and Remote Sensing Symposium (IGARSS) | Year: 2013
This Pléiades system is made of two 'small satellites' (mass of one ton) offering a spatial resolution at nadir of 0.7 meters and a field of view of 20 kilometers. © 2013 IEEE.
Agnew M.,Paradigm |
Renouard L.,Astrium Geo Information Services |
30th AIAA International Communications Satellite System Conference (ICSSC), 2012 | Year: 2012
The European Data Relay System (EDRS), known as ‘SpaceDataHighway’, uses two GEO satellites as data relay nodes. The system will provide a near-real-time telecommunication service between spacecraft &/or high altitude airborne platforms (HAPs) and the ground. Key benefits of the system include: Extended platform communications range Beyond Line of Sight (BLOS), Interception of all orbits, Higher data rates resulting in >50Tb per day data relay traffic capacity from just one GEO node. Services such as sensor data relay at up to 1800Mbps (using laser intersatellite links), high speed tasking at 1Mbps (close-loop) and platform/sensor telemetry at 1-10Mbps result in the world's first commercial Data Relay & Tasking service to LEO & HAP platforms. In addition, the system will enable near real-time services with very low data latency (in minutes, rather than hours). Furthermore, new services are enabled by the SpaceDataHighway eg. 'Confirmed Delivery'… The future extension of the system with two further nodes will provide complete global coverage and long-term system redundancy beyond 2030. © 2012 by the authors. Published by FGM Events LLC and distributed by AIAA with permission. All other rights reserved.
Lang O.,Astrium GEO Information Services |
Lumsdon P.,Astrium GEO Information Services
International Geoscience and Remote Sensing Symposium (IGARSS) | Year: 2011
Satellite image mosaics are commonly used for large-scale mapping purposes. Perpetual cloud cover may prohibit the mapping with electro-optical satellite imagery within a reasonable time interval, e.g. in tropical areas. In these cases, the additional use of SAR data can help to complement the image of the earth surface, as cloud-independent spaceborne SAR data has been proven to be a valuable thematic and topographic mapping source . An effective way to realize an integrated image mosaic is the colorization of high-resolution SAR imagery by applying statistical filters and the adaptation of these false colors with respect to an optical reference. The creation of SAR images with a land-cover related color scheme has been shown before . But generally, the resulting images have no relationship to the color impression of an optical scene. The motivation of the technique described in this paper is • to create automatically colour classified products directly from single polarized SAR images • to create seamless mosaics from colored SAR images • to mosaic colored SAR images with electro-optical imagery © 2011 IEEE.
Dick J.,Astrium GEO Information Services
GEO: connexion | Year: 2013
Cloud and big data offer the next stage in the geospatial data revolution. Across nearly every industry, big data has emerged as both opportunity and challenge, and the geospatial sector is no exception. Indeed, as the number, variety, and sophistication of earth-imaging satellites orbiting the globe intensifies, the quantity, complexity, and applicability of the data they send back to Earth will only grow. But if big data represents the geospatial industry's aggregate potential for revolutionizing the way such industries look at the world, it is through the cloud that this transformation will actually take place. For it is in the cloud that these enormous repositories of data can not only be properly managed and stored but also processed and mined for the kinds of operational intelligence that is of tangible, mission critical value to organizations.
Gaoxiang H.,Airbus |
Bignone F.,Astrium geo information services
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives | Year: 2012
A totally new automatic workflow mechanism, named Second generation Mosaic module, based on the well-known Pixel Factory system, will be introduced here, which enables existing digital orthoimages and mosaics to be quickly updated. The process extracts all required parameters from the reference database to be able to perform automatic bundle adjustment and radiometric adaptation.In this paper, two examples for both satellite data and aerial data processed based on this mechanism will be presented here and discussed. Finally, the cost reduction will also be analysed according to the real mapping updating project.In a final statement, this paper will present an integrated solution named second generation mosaic module based on the well-known Pixel Factory system which is completely dedicated to fast processing of photogrammetric products Thanks to this integrated hardware and software solution, it is even possible to manage large data volume quickly in order to have precise map updating information as soon as possible after acquisition.