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Termes IGN > sciences naturelles > physique > optique > optique physique > radiométrie > rayonnement électromagnétique > spectre électromagnétique > bande spectrale
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Sea ice deformation state from Synthetic Aperture Radar Imagery: part 2 Effects of spatial resolution and noise level / W. Dierking in IEEE Transactions on geoscience and remote sensing, vol 46 n° 8 (August 2008)
[article]
Titre : Sea ice deformation state from Synthetic Aperture Radar Imagery: part 2 Effects of spatial resolution and noise level Type de document : Article/Communication Auteurs : W. Dierking, Auteur ; J. Dall, Auteur Année de publication : 2008 Article en page(s) : pp 2197 - 2207 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande C
[Termes IGN] bande L
[Termes IGN] filtrage du bruit
[Termes IGN] glace de mer
[Termes IGN] image aérienne
[Termes IGN] image ALOS-PALSAR
[Termes IGN] image Envisat-ASAR
[Termes IGN] image ERS-SAR
[Termes IGN] image radar
[Termes IGN] pouvoir de résolution géométrique
[Termes IGN] radargrammétrie
[Termes IGN] rapport signal sur bruitRésumé : (Auteur) C- and L-band airborne synthetic aperture radar (SAR) imagery acquired at like- and cross-polarizations over sea ice under winter conditions is examined with the objective to study the discrimination between level ice and ice deformation features. High-resolution low-noise data were analyzed in the first paper. In this second paper, the main topics are the effects of spatial resolution and signal-to-noise ratio. Airborne high-resolution SAR scenes are used to generate a sequence of images with increasingly coarser spatial resolution from 5 to 25 m, keeping the number of looks constant. The signal-to-noise ratio is varied between typical noise levels for airborne imagery and satellite data. Areal fraction of deformed ice and average deformation distance are determined for each image product. At L-band, the retrieved values of the areal fraction get larger as the image resolution is degraded. The areal fraction at C-band remains constant. The retrieved average distance between deformation features increases both at C- and L-bands as the image resolution gets coarser. The influence of noise becomes noticeable if its level is equal or larger than the average intensity backscattered from the level ice. The retrieval of deformation parameters using simulated images that resemble ERS-2 SAR, Envisat ASAR, and ALOS PALSAR data products is discussed. Basic differences between real and simulated ERS-2 SAR images are analyzed. Copyright IEEE Numéro de notice : A2008-398 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2008.917267 En ligne : https://doi.org/10.1109/TGRS.2008.917267 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29487
in IEEE Transactions on geoscience and remote sensing > vol 46 n° 8 (August 2008) . - pp 2197 - 2207[article]Voir aussiRéservation
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Code-barres Cote Support Localisation Section Disponibilité 065-08081 RAB Revue Centre de documentation En réserve L003 Disponible
Titre : On generalized signal waveforms for satellite navigation Type de document : Thèse/HDR Auteurs : José Avila-Rodriguez, Auteur Editeur : Munich : Universität der Bundeswehr Année de publication : 2008 Importance : 438 p. Format : 21 x 30 cm Note générale : bibliographie
Vollständiger Abdruck der bei der Fakultät für Luft- und Raumfahrttechnik der Universität der Bundeswehr München zur Erlangung des akademischen Grades eines Doktor-Ingenieurs (Dr.-Ing.) eingereichten Dissertation / A thesis submitted to the faculty of aerospace engineering in fulfillment of the requirements for the degree of doctor of engineeringLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] bande spectrale
[Termes IGN] forme d'onde
[Termes IGN] modulation de fréquence
[Termes IGN] modulation du signal
[Termes IGN] onde porteuse
[Termes IGN] signal GNSSRésumé : (auteur) This thesis provides a comprehensive overview of all current and planned satellite navigation systems, either global or regional, putting special emphasis on their signal structure. Particular attention is paid to the European Global Navigation Satellite System Galileo, under development at the moment. The results of this work can be considered as a significant contribution to the design and development of the Galileo’s Open Service (OS) in the E1 frequency band. The present work provides as main contribution a generally valid theoretical framework with which all current and future navigation signals can be described. Generalized signal waveforms and their corresponding time and spectral characteristics are derived and investigated. Complete families of signals are presented and analyzed regarding their spectral and performance characteristics, underlining their potential for future generations of satellite navigation systems. This thesis proves that the generalized signal waveforms proposed in this work cover any current and other optimized signals that could be proposed in the future. In this sense, it is shown that all current navigation signals can be mathematically described as Multilevel Coded spreading Symbols or, in particular, as Binary Coded Symbols. Using the analytical expressions of the generalized signal model, the corresponding generalized signal waveforms are further studied regarding their Spectral Separation Coefficients (SSCs). This parameter is of great interest in satellite navigation to understand the compatibility between different signals. Generalized formulas for smooth spectra are also derived to calculate the SSCs between any two arbitrary signals. Particular cases of interest are computed following the obtained analytical expressions and by means of simulations with real Pseudo Random Noise (PRN) codes. Results from this comparison show a perfect matching between the predicted analytical results and the numerical computations. Realistic scenarios are carried out to assess the impact of non-ideal PRN codes and navigation data onto the spectral properties that have been derived analytically. Finally, current and new multiplexing schemes are studied in detail together with the feasibility to introduce optimized signal waveforms. Special attention is paid to understand the required changes that are necessary to multiplex non-binary signals. Pros and Cons of the different solutions are discussed and investigated with regard to the application of future signal waveforms. Among these last ones, the Composite Binary Offset Carrier (CBOC) implementation of the Multiplexed Binary Offset Carrier (MBOC) modulation for the Galileo’s Open Service signal in the E1 frequency band deserves an important chapter. In addition, some chapters are dedicated to analyze receiver structures optimized to work with MBOC for both GPS and Galileo. Note de contenu : 1. Introduction
1.1 Objectives of this Thesis
1.2 Contributions of this Thesis
1.3 Thesis Outline
2. Global Navigation Satellite Systems (GNSS)
2.1 GNSS – Thinking global
2.2 Scenes from the Present
2.3 The Global Positioning System (GPS
2.4 Galileo
2.5 GLONASS
2.6 Compass
2.7 Summary on Global Navigation Satellite Systems
2.8 Regional Satellite Navigation Systems
2.9 GNSS Augmentation Systems
2.10 Pseudolites
3. Galileo Baseline Evolution
3.1 Introduction
3.2 Square-Root Raised Cosine (SRRC) Signal waveforms for Galileo ?
3.3 Galileo Baseline of 2002
3.4 The Long Way to the Agreement
3.5 Agreement of 2004: BOC(1,1)+BOCcos(15, 2.5)
3.6 The Way to Today’s Baseline
3.7 MBOC(6,1)
4. GNSS Signal Structure
4.1 GNSS Modulation Schemes
4.2 Multilevel Coded Spreading Symbols (MCS)
4.3 Binary Coded Symbols (BCS)
4.4 Sinusoidal Multilevel Coded Symbol (SMCS) Signals
4.5 Generalized Multilevel Coded Symbols (GMCS)
4.6 CBCS Modulation definition and analysis of performance
4.7 MBOC modulation definition and analysis
4.8 Other Modulation Schemes
5. Spectral Separation Coefficient (SSC)
5.1 Definition
5.2 Derivation of analytical expressions
6. Spectral Separation Coefficients with data and non ideal codes
6.1 Analytical expressions when data is present
6.2 Computation of non-ideal Spectral Separation Coefficients
7. Signal Multiplex Techniques for GNSS
7.1 Introduction
7.2 Multiplexing Schemes
7.3 Linear Modulation (Spatial Combining)
7.4 Majority Signal Voting
7.5 Hard Limiting
7.6 Quadrature Product Sub-carrier Modulation
7.7 Coherent Adaptive Sub-Carrier Modulation (CASM) and Interplex
7.8 Intervoting (Interplex + Majority Voting
7.9 FDMA vs. CDMA
8. Conclusions and Recommendations
8.1 Conclusions
8.2 Recommendations for Future WorkNuméro de notice : 14903 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Note de thèse : PhD : aerospace engineering : Universität der Bundeswehr München : 2008 DOI : sans En ligne : http://athene-forschung.unibw.de/node?id=86167 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76793 Sea-ice deformation state from synthetic aperture radar imagery: Part 1 comparison of C- and L-band and different polarization / W. Dierking in IEEE Transactions on geoscience and remote sensing, vol 45 n° 11 Tome 2 (November 2007)
[article]
Titre : Sea-ice deformation state from synthetic aperture radar imagery: Part 1 comparison of C- and L-band and different polarization Type de document : Article/Communication Auteurs : W. Dierking, Auteur ; J. Dall, Auteur Année de publication : 2007 Article en page(s) : pp 3610 - 3622 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] analyse comparative
[Termes IGN] bande C
[Termes IGN] bande L
[Termes IGN] classification dirigée
[Termes IGN] glace de mer
[Termes IGN] image radar moirée
[Termes IGN] polarimétrie radar
[Termes IGN] polarisationRésumé : (Auteur) In this paper, we present a quantitative comparison of L- and C-band airborne synthetic aperture radar imagery acquired at like- and cross-polarizations over deformed sea ice under winter conditions. The parameters characterizing the deformation state of the ice are determined at both radar bands and at different polarizations. The separation of deformed and level ice is based on a target detection technique. The threshold is set such that image pixels with intensities equal to or larger than the highest 2% of the level-ice intensity distribution are classified as deformed ice, independent of the radar configuration and ice conditions. Optical imagery of sufficient quality for comparison is available only in a very few cases. To characterize the deformation state, the areal fraction of deformation features and the average distance between these features are evaluated. The values obtained for both parameters are very sensitive to the radar frequency. Aeral fractions are larger, and average distances are smaller at L-band than at C-band because of the much higher intensity contrast between the deformed and level ice at L-band. The differences between polarizations at one radar band are smaller but not always negligible. In comparison to optical images, it was observed that deformed-ice areas can be distinguished from level ice over their whole length and exten-sion at L-band, whereas at C-band, often, only prominent parts are visible. Numéro de notice : A2007-508 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2007.903711 En ligne : https://doi.org/10.1109/TGRS.2007.903711 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28871
in IEEE Transactions on geoscience and remote sensing > vol 45 n° 11 Tome 2 (November 2007) . - pp 3610 - 3622[article]Voir aussiRéservation
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Code-barres Cote Support Localisation Section Disponibilité 065-07111B RAB Revue Centre de documentation En réserve L003 Disponible Bright-band detection from radar vertical reflectivity profiles / M.A. Rico-Ramirez in International Journal of Remote Sensing IJRS, vol 28 n°17-18 (September 2007)
[article]
Titre : Bright-band detection from radar vertical reflectivity profiles Type de document : Article/Communication Auteurs : M.A. Rico-Ramirez, Auteur ; I.D. Cluckie, Auteur Année de publication : 2007 Article en page(s) : pp 4013 - 4025 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande spectrale
[Termes IGN] estimation statistique
[Termes IGN] hydrologie
[Termes IGN] image radar
[Termes IGN] luminance lumineuse
[Termes IGN] précipitation
[Termes IGN] réflectance directionnelle
[Termes IGN] réflectivitéRésumé : (Auteur) The use of quantitative scanning weather radar for precipitation measurements is a vital element of modern hydrology and limits the development of all distributed models of catchment behaviour. The presence of the so-called bright band (or melting layer) contaminates the quantitative precipitation estimates and has delayed the widespread take-up of radar-based precipitation estimates in operational models. The study of the Vertical Reflectivity Profile (VRP) of precipitation is important in order to develop algorithms to correct scanning weather radar measurements for the variation of the VRP at long ranges. Therefore, this paper presents an algorithm to detect the extent of the bright band using high-resolution VRP's. The boundaries of the bright band are identified by a new algorithm which utilizes a rotational coordinate system for identifying the upper and lower parts of the bright band. This overcomes some of the difficulties experienced when using the gradient of the reflectivity in conventional bright-band detection algorithms. The reflectivities above, within, and below the bright band are then used to construct idealized VRP's to correct scanning weather radar measurements. Copyright Taylor & Francis Numéro de notice : A2007-405 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160601047797 En ligne : https://doi.org/10.1080/01431160601047797 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28768
in International Journal of Remote Sensing IJRS > vol 28 n°17-18 (September 2007) . - pp 4013 - 4025[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 080-07101 RAB Revue Centre de documentation En réserve L003 Disponible PALSAR data without ground control points / Penggen Cheng in Geoinformatics, vol 10 n° 6 (01/09/2007)
[article]
Titre : PALSAR data without ground control points Type de document : Article/Communication Auteurs : Penggen Cheng, Auteur Année de publication : 2007 Article en page(s) : pp 36 - 38 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande L
[Termes IGN] géoréférencement direct
[Termes IGN] image ALOS
[Termes IGN] image ALOS-PALSAR
[Termes IGN] image radar
[Termes IGN] mosaïquage d'images
[Termes IGN] orthophotoplan numérique
[Termes IGN] orthorectification
[Termes IGN] point d'appui
[Termes IGN] radargrammétrieRésumé : (Auteur) Imagine a fully automated, highly reliable system to produce high-accuracy orthos and mosaics of radar data all over the world. Time-sensitive applications such as oil spills flood monitoring can now access high-accuracy radar orthos as soon as data is available. These applications and more are now possible with the successful operation of the ALOS satellite. Copyright GEOinformatics Numéro de notice : A2007-417 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28780
in Geoinformatics > vol 10 n° 6 (01/09/2007) . - pp 36 - 38[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 262-07061 SL Revue Centre de documentation Revues en salle Disponible Dual-frequency altimeter signal from Envisat on the Amery ice-shelf / Pascal Lacroix in Remote sensing of environment, vol 109 n° 3 (15 August 2007)PermalinkSentinel-1, the radar mission for GMES operational land and sea services / E. Attema in ESA bulletin, n° 131 (August 2007)PermalinkSentinel-2, the optical high-resolution mission for GMES operational services / P. Martimort in ESA bulletin, n° 131 (August 2007)PermalinkUrban radiation balance of two coastal cities in a hot and dry environment / C.M. Frey in International Journal of Remote Sensing IJRS, vol 28 n°11-12 (June 2007)PermalinkActive forest monitoring in Uttaranchal state, India using multi-temporal DMSP-OLS and MODIS data / T.R. Kiranchand in International Journal of Remote Sensing IJRS, vol 28 n° 10 (May 2007)PermalinkQuality assessment of SRTM C- and X-band interferometric data: Implications for the retrieval of vegetation canopy height / W.S. Walker in Remote sensing of environment, vol 106 n° 4 (28/02/2007)PermalinkExtraction of spectral channels from hyperspectral images for classification purposes / S.B. Serpico in IEEE Transactions on geoscience and remote sensing, vol 45 n° 2 (February 2007)PermalinkEvaluating NDVI-based emissivities of MODIS bands 31 and 32 using emissivities derived by day/night LST algorithm / M. Momeni in Remote sensing of environment, vol 106 n° 2 (30/01/2007)PermalinkComparison of L- and X-band PolSAR data for characterization of polarization orientation angle shift induced by man-made structure / K. Iribe (2007)PermalinkContinuum removed band depth analysis for detecting the effects of natural gas, methane and ethane reflectance / M.F. Noomen in Remote sensing of environment, vol 105 n° 3 (15/12/2006)Permalink