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Physical limitations on detecting tunnels using underground-focusing spotlight synthetic aperture radar / J. Martinez-Lorenzo in IEEE Transactions on geoscience and remote sensing, vol 49 n° 1 Tome 1 (January 2011)
[article]
Titre : Physical limitations on detecting tunnels using underground-focusing spotlight synthetic aperture radar Type de document : Article/Communication Auteurs : J. Martinez-Lorenzo, Auteur ; C. Rappaport, Auteur ; F. Quivira, Auteur Année de publication : 2011 Conférence : IGARSS 2009, International Geoscience And Remote Sensing Symposium 12/07/2009 17/07/2009 Le Cap Afrique du sud Proceedings IEEE Article en page(s) : pp 65 - 70 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] constante diélectrique
[Termes IGN] détection de partie cachée
[Termes IGN] écho radar
[Termes IGN] forme d'onde
[Termes IGN] image radar moirée
[Termes IGN] propagation du signal
[Termes IGN] réflectance du sol
[Termes IGN] réfraction atmosphérique
[Termes IGN] rugosité du sol
[Termes IGN] sable
[Termes IGN] tunnelRésumé : (Auteur) This paper examines the feasibility of underground-focusing spotlight synthetic aperture radar (UF-SL-SAR) systems for tunnel detection applications. A general formulation is reviewed for generating UF-SL-SAR imaging by using multiple frequencies across a wide band and by focusing in space to subsurface points using well-known ray refraction at the nominal ground surface. A full-wave finite-difference frequency-domain model is used to consider wave propagation in realistic soil with loss- and frequency-dependent dielectric constant and a randomly rough ground surface, both of which serve to obscure and distort the returned tunnel target signal. Imaging results are presented for two representative soil scenarios: dry sand and moist clay loam. Considering the ground surface ray refraction for focusing greatly improves the SAR image relative to conventional SAR focusing at the ground surface. Using UF-SL-SAR, a small shallow tunnel is reasonably imaged for the sand case, despite the roughness of the ground interface. However, for higher conductivity moist clay loam, the clutter from the rough surface overwhelms the significantly attenuated target signal, which must propagate through the lossy intervening soil. It is demonstrated that, despite ideal focusing, the tunnel is successfully imaged only for the sand case. Numéro de notice : A2011-048 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2010.2051952 Date de publication en ligne : 19/08/2010 En ligne : https://doi.org/10.1109/TGRS.2010.2051952 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30829
in IEEE Transactions on geoscience and remote sensing > vol 49 n° 1 Tome 1 (January 2011) . - pp 65 - 70[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2011011A RAB Revue Centre de documentation En réserve L003 Disponible Uncertainty within satellite LiDAR estimations of vegetation and topography / J. Rosette in International Journal of Remote Sensing IJRS, vol 31 n° 5 (March 2010)
[article]
Titre : Uncertainty within satellite LiDAR estimations of vegetation and topography Type de document : Article/Communication Auteurs : J. Rosette, Auteur ; P. North, Auteur ; J. Suarez, Auteur ; S. Los, Auteur Année de publication : 2010 Conférence : Silvilaser 2008, 8th international conference on Lidar applications in forest assessment and inventory 17/09/2008 19/09/2008 Edimbourg Royaume-Uni Proceedings Taylor&Francis Article en page(s) : pp 1325 - 1342 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] altimétrie satellitaire par laser
[Termes IGN] canopée
[Termes IGN] décomposition de Gauss
[Termes IGN] données ICEsat
[Termes IGN] forme d'onde
[Termes IGN] hauteur des arbres
[Termes IGN] modèle de transfert radiatif
[Termes IGN] modèle numérique de surface
[Termes IGN] pente
[Termes IGN] reliefRésumé : (Auteur) This paper demonstrates the ability to identify representative ground elevation and vegetation height estimates within the Ice, Cloud and land Elevation Satellite/Geoscience Laser Altimeter System (ICESat/GLAS) waveforms for an area of mixed vegetation and varied topography. Estimating vegetation height within large-footprint Light Detection and Ranging (LiDAR) waveforms relies on the ability to estimate the uppermost canopy surface (signal beginning) and an elevation representing the ground surface, both of which are influenced by vegetation properties and topographic slope. We examined sources of uncertainty for vegetation height estimation from ICESat/GLAS data using airborne LiDAR data, field measurements and the FLIGHT radiative transfer model. In comparison with an independent 10-m resolution digital terrain model (DTM), a method using Gaussian decomposition of the satellite waveform produced a mean bias of -0.10 m when estimating ground elevation. A second method of estimating vegetation height using waveform extent and a terrain index effectively removed slope as an error source but produced a greater ground surface offset (-0.83 m). The two methods of estimating vegetation height compared well with airborne LiDAR estimates (correlation coefficient (R2) = 0.68, root mean square error (RMSE) = 4.4 m and R2 = 0.61, RMSE = 4.9 m, respectively). However, the complex interplay of the structural and optical properties of the intercepted vegetation and slope requires further understanding. A tool such as FLIGHT provides a useful means to explore the sensitivity of the waveform to both vegetation properties and topographic slope. Numéro de notice : A2010-253 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160903380631 En ligne : https://doi.org/10.1080/01431160903380631 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30447
in International Journal of Remote Sensing IJRS > vol 31 n° 5 (March 2010) . - pp 1325 - 1342[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-2010031 RAB Revue Centre de documentation En réserve L003 Exclu du prêt
Titre : Lidar waveform modeling using a marked point process Type de document : Article/Communication Auteurs : Clément Mallet , Auteur ; Florent Lafarge, Auteur ; Uwe Soergel, Auteur ; Christian Heipke, Auteur ; Frédéric Bretar, Auteur Editeur : New York : Institute of Electrical and Electronics Engineers IEEE Année de publication : 07/11/2009 Conférence : ICIP 2009, 16th IEEE International Conference on Image Processing 07/11/2009 10/11/2009 Le Caire Egypte Proceedings IEEE Importance : 4 p. Format : 21 x 30 cm Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] algorithme du recuit simulé
[Termes IGN] chaîne de Markov
[Termes IGN] données localisées 3D
[Termes IGN] forme d'onde
[Termes IGN] lasergrammétrie
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] milieu urbain
[Termes IGN] processus ponctuel marqué
[Termes IGN] reconstruction du signal
[Termes IGN] semis de points
[Termes IGN] signal laser
[Termes IGN] signal lidarRésumé : (Auteur) Lidar waveforms are 1D signal consisting of a train of echoes where each of them correspond to a scattering target of the Earth surface. Modeling these echoes with the appropriate parametric function is necessary to retrieve physical information about these objects and characterize their properties. This paper presents a marked point process based model to reconstruct a lidar signal in terms of a set of parametric functions. The model takes into account both a data term which measures the coherence between the models and the waveforms, and a regularizing term which introduces physical knowledge on the reconstructed signal. We search for the best configuration of functions by performing a Reversible Jump Markov Chain Monte Carlo sampler coupled with a simulated annealing. Results are finally presented on different kinds of signals in urban areas. Numéro de notice : C2009-048 Affiliation des auteurs : MATIS+Ext (1993-2011) Thématique : IMAGERIE/POSITIONNEMENT Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1109/ICIP.2009.5413380 En ligne : https://doi.org/10.1109/ICIP.2009.5413380 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=64296 Documents numériques
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Lidar waveform modeling ... - pdf auteurAdobe Acrobat PDF Analyse et traitement d'ondes Lidar pour la cartographie et la reconnaissance de formes : application au milieu urbain / Clément Mallet (2008)
Titre : Analyse et traitement d'ondes Lidar pour la cartographie et la reconnaissance de formes : application au milieu urbain Titre original : Lidar waveform analysis and processing for cartography and pattern recognition: application to urban areas Type de document : Article/Communication Auteurs : Clément Mallet , Auteur ; Adrien Chauve , Auteur ; Frédéric Bretar, Auteur Editeur : Orsay, Chambéry : Association Française de l'Intelligence Artificielle AFIA Année de publication : 2008 Conférence : RFIA 2008, 16e conférence Reconnaissance des Formes et Intelligence Artificielle 22/01/2008 25/01/2008 Amiens France Proceedings IEEE Importance : pp 693 - 702 Format : 21 x 30 cm Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] classification dirigée
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] forme d'onde
[Termes IGN] milieu urbain
[Termes IGN] onde électromagnétique
[Termes IGN] reconnaissance de formes
[Termes IGN] segmentation
[Termes IGN] semis de points
[Termes IGN] signal laserRésumé : (Auteur) Toute onde lidar rétrodiffusée par la surface terrestre contient des informations sur les cibles atteintes ayant contribué à la forme de l’onde. Les systèmes lidar capables de numériser l’intégralité des signaux retour sont apparus récemment et permettent le traitement a posteriori de ces profils altimétriques. Nous présentons dans cet article une méthode d’analyse puis de traitement des ondes lidar dans un contexte de cartographie automatique. Tout d’abord, nous montrons que l’analyse fine des ondes permet une densification des nuages de points 3D. Dans un second temps, le traitement a posteriori des signaux conduit à leur modélisation sous forme paramétrique. Nous proposons alors une méthode de reconnaissance de formes appliquée au milieu urbain. Une classification supervisée par Séparateurs à Vaste Marge est ainsi employée pour prendre en compte les caractéristiques des échos extraits lors de la phase de traitement. Les résultats montrent que la segmentation d’une zone urbaine en classes bâti, végétation, sol naturel et sol artificiel est possible à partir des ondes lidar seulement. Numéro de notice : 13576 Affiliation des auteurs : MATIS (1993-2011) Thématique : IMAGERIE Nature : Communication DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=64263 Documents numériques
en open access
13576_art_analyse_ondes_lidar_mallet.pdfAdobe Acrobat PDF
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 Fundamentals of radar signal processing / M. Richards (2005)PermalinkInitial analysis and visualization of waveform laser scanner data / Johanna Töpel (2005)Permalink