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LIDAR : une technique prometteuse / Françoise de Blomac in SIG la lettre, n° 83 (janvier 2007)
[article]
Titre : LIDAR : une technique prometteuse Type de document : Article/Communication Auteurs : Françoise de Blomac, Auteur Année de publication : 2007 Article en page(s) : pp 7 - 8 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] capteur actif
[Termes IGN] données bathymétriques
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] données topographiques
[Termes IGN] écho
[Termes IGN] filtrage du bruit
[Termes IGN] géoréférencement direct
[Termes IGN] GPS-INS
[Termes IGN] lasergrammétrie
[Termes IGN] Lidar
[Termes IGN] modèle numérique de terrain
[Termes IGN] plan de vol
[Termes IGN] rayonnement lumineux
[Termes IGN] réflectance végétale
[Termes IGN] semis de points
[Termes IGN] signal laser
[Termes IGN] télémètre laser à balayage
[Termes IGN] télémétrie laser aéroporté
[Termes IGN] végétationRésumé : (Auteur) Même si la France ne compte encore aujourd'hui aucun système de laser aéroporté (aussi appelé LIDAR), plusieurs expériences ont déjà été menées avec cette technique d'acquisition, dans les domaines de la topographie, de la végétation, du littoral ou de la gestion des infrastructures. La technique est prometteuse et permet de voir des détails invisibles avec d'autres méthodes. Va-t-elle pour autant remplacer la photogrammétrie ? Les deux approches sont sans doute plus complémentaires que concurrentes, comme l'ont montré les experts rassemblés à l'atelier REGLIS 2006 organisé par le CEMAGREF et l'IGN à Montpellier en décembre dernier avec le soutien du CNES. Copyright SIG La Lettre Numéro de notice : A2007-002 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28368
in SIG la lettre > n° 83 (janvier 2007) . - pp 7 - 8[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 286-07011 RAB Revue Centre de documentation En réserve L003 Disponible Calibration of the optech ALTM-3100 laser scanner intensity data using brightness targets / E. Ahokas in Revue Française de Photogrammétrie et de Télédétection, n° 182 (Juin 2006)
[article]
Titre : Calibration of the optech ALTM-3100 laser scanner intensity data using brightness targets Type de document : Article/Communication Auteurs : E. Ahokas, Auteur ; S. Kaasalainen, Auteur ; et al., Auteur Année de publication : 2006 Conférence : ISPRS 2006, Commission 1 Symposium, From sensors to imagery 03/07/2006 06/07/2006 Champs-sur-Marne [Paris Marne-la-Vallée] France OA ISPRS Archives Article en page(s) : pp 10 - 16 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] ALTM
[Termes IGN] angle d'incidence
[Termes IGN] angle de visée
[Termes IGN] caméra numérique
[Termes IGN] correction atmosphérique
[Termes IGN] étalonnage en vol
[Termes IGN] étalonnage géométrique
[Termes IGN] étalonnage radiométrique
[Termes IGN] Lidar
[Termes IGN] point d'appui
[Termes IGN] rapport signal sur bruit
[Termes IGN] test de performanceRésumé : (Auteur) In this paper the calibration of Optech ALTM 3100 laser scanner intensity is reported using airborne experiments and known brightness targets. The Finnish Geodetic Institute has had a permanent photogrammetric test field in Sjokulla Kirkkonummi since 1994. This test field contains permanent and transportable test targets for radiometric calibration, permanent ground control points for small, medium and large-scale geometric calibration and also test bar targets for spatial analysis of analogue and digital aerial cameras. Since 2000 LiDAR testing has also been carried out, the latest being Optech ALTM 3100 campaign in 12-14 July 2005. Eight portable brightness targets with nominal reflectance of 5 %, 10 %, 20 %, 25 %, 30 %, 45 %, 50 % and 70 % were in use for LiDAR testing. Flying heights were about 200, 1000 and 3000 m above ground level. Intensity values need to be corrected with respect to range, incidence angle (both BRDF and range correction), atmospheric transmittance, attenuation using dark object addition and transmitted power (because difference in PRF will lead to different transmitter power values). After these corrections, the intensity values were directly relative to target reflectance. Flight heights of 200 m and 1000 m are suitable for intensity calibration using artificial test targets due to the practical aspects of the calibration (size of the calibrator). With the 3000 m altitude signals with reflectance of less or equal of 10% could not be recorded most probably due to insufficient signal-to-noise ratio. Thus, the test target reflectance should exceed 10% to give a reliable distance measurement from 3000 m altitude. Numéro de notice : A2006-618 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans En ligne : https://www.isprs.org/proceedings/XXXVI/part1/Papers/T03-11.pdf Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28341
in Revue Française de Photogrammétrie et de Télédétection > n° 182 (Juin 2006) . - pp 10 - 16[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 018-06021 RAB Revue Centre de documentation En réserve L003 Disponible Improving the precision and accuracy of geodetic GPS / A. Bilich (2006)
Titre : Improving the precision and accuracy of geodetic GPS : applications to multipath and seismology Type de document : Thèse/HDR Auteurs : A. Bilich, Auteur ; K. Larson, Directeur de thèse Editeur : Boulder [Etats-Unis] : University of Colorado Année de publication : 2006 Importance : 374 p. Format : 21 x 28 cm ISBN/ISSN/EAN : 978-0-542-94205-1 Note générale : Bibliographie
A thesis submitted to the Faculty of the graduate school of the University of Colorado in partial fulfillment of the requirements for the degree of Doctor of philosophy, department of aerospace engineering sciencesLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] égalisation
[Termes IGN] erreur de positionnement
[Termes IGN] filtrage du bruit
[Termes IGN] mesurage de phase
[Termes IGN] mesurage de pseudo-distance
[Termes IGN] positionnement par GPS
[Termes IGN] rapport signal sur bruit
[Termes IGN] réduction
[Termes IGN] séisme
[Termes IGN] sismologie
[Termes IGN] trajet multipleIndex. décimale : THESE Thèses et HDR Résumé : (Auteur) The Global Positioning System (GPS) enables precise and accurate determination of position anywhere on anywhere on the Earth, a boon to the field of geodesy. Although great advances in geodetic GPS positioning precision and accuracy have been made over the last decade, improvements can still be made. This dissertation addresses GPS positioning error from two different directions---understanding and taking advantage of the repeating nature of some errors, or understanding and taking advantage of the relationship between errors in different contemporaneous GPS observables. In the area of high-rate GPS positioning, repeating errors have a substantial impact on the solution. In this dissertation, I study high-rate GPS error reduction using data from the 2002 Denali Fault earthquake. I apply the techniques of modified sidereal filtering and spatial filtering to positions from 25 GPS stations throughout northwestern North America, and I develop improvements to these methods such as data equalization and careful selection of sidereal filtering sites. Substantial reduction in noise magnitude is achieved through proper application of sidereal and spatial filters, and the resulting 'GPS seismograms' show excellent agreement to records from seismometers. Multipath, where GPS signals arrive by more than one path and thereby create a range error, can be understood through the GPS observables. Multipath effects on GPS carrier phase, pseudorange, and signal-to-noise ratio (SNR) measurements are different but linked by the same underlying principles. In this dissertation, I explain multipath effects on the GPS observables and define multipath in terms of conditions specific to geodetic GPS installations and receivers. I develop two approaches to multipath errors, both using SNR measurements---a graphical method for multipath assessment, and a computational method for multipath modeling and carrier phase error reduction. The graphical method shows great promise for understanding spatial and temporal variability in multipath errors, but provides no avenue for removing these errors. The theory behind SNR modeling is robust, but complicated to implement with geodetic GPS measurements of SNR. I discuss the difficulties inherent in SNR modeling and demonstrate how this technique is of limited utility for geodetic GPS even in the most simple of multipath environments. Note de contenu : 1 Introduction
1.1 Global Positioning System Background
1.2 GPS Observables
1.3 Position Estimation with GIPSY
1.3.1 Satellite Orbits
1.3.2 Earth and Observation Models
1.3.3 Removing Ionospheric Effects
1.3.4 Unmodeled Terms
1.3.5 Position Solution
2 Overview of High-Rate Positioning Research
2.1 Comparision of GPS and Seismologic Measurements
2.2 Previous Work in GPS Seismology
2.3 Case Study: 2002 November 3 Denali Fault Event
2.3.1 Denali Fault earthquake
2.3.2 GPS network and analysis
2.3.3 Error-reduction methodology
3 High-rate GPS Techniques
3.1 Sidereal Filtering
3.1.1 Orbital repeat period
3.1.2 Modified sidereal filtering (MSF) method
3.1.3 Variables in sidereal filtering process
3.2 Additional Data Analysis
3.2.1 Ambiguity resolution
3.2.2 Data editing
3.3 Spatial Filtering
3.3.1 Common-mode errors
3.3.2 Spatial filtering method
3.3.3 Spatial filtering sites
3.3.4 Role of the reference site and filter order
4 High-rate GPS Results and Discussion
4.1 Surface Waves Recorded by GPS
4.2 Positioning Noise
4.2.1 Noise floor of GPS receivers
4.2.2 Generalized noise in GPS positions
4.3 Comparison to Seismic Recordings
4.4 Summary and Conclusions
4.5 Future Work
5 Overview of Multipath Research
5.1 Previous Work
5.2 Research Motivation and Overview
6 Principles of Multipath and SNR
6.1 GPS Receiver Signal Tracking
6.2 Multipath Terminology
6.3 Multipath Effects on GPS Observables
6.3.1 Pseudorange multipath
6.3.2 Carrier phase multipath
6.3.3 Effect of multipath on SNR
6.4 Summary of Multipath Theory
7 Multipath Under Geodetic GPS Conditions
7.1 Multipath Geometry for the Geodetic Case
7.1.1 Multipath geometry and errors
7.1.2 Time-varying behavior of ø and SNR
7.1.3 Multipath geometry and periodicity
7.1.4 Resolvable multipath frequencies
7.1.5 Multipath phasor spin
7.1.6 Direct and multipath amplitudes
7.1.7 Summary
7.2 Geodetic GPS Receivers
7.2.1 Computation and reporting of SNR
7.2.2 Characteristics of geodetic GPS SNR
7.2.3 Correlation of SNR and pseudorange multipath
7.2.4 Conclusions
8 Multipath Assessment for Permanent GPS Stations
8.1 SNR Power Spectral Maps
8.1.1 Spectral power estimates
8.1.2 Representation of gridded spectral power
8.2 Examples of Power Spectral Maps
8.2.1 TASH: tall pillar
8.2.2 MKEA: reflections from angled surfaces
8.2.3 CHUR: variable topography
8.3 Discussion and Future Work
9 Estimation of SNR-based Multipath Corrections
9.1 Direct Signal Amplitude and SNR Due to Multipath
9.2 Signal Conditioning
9.3 Multipath Frequency Estimation Via Sliding-Window Fast Fourier Transform (SWFFT)
9.4 Amplitude and Multipath Phase Estimation Via Adaptive Least Squares (ALS)
9.5 Construction of SNR and Multipath Corrections
9.6 Simulations
10 Phase Multipath Mitigation for GPS Stations
10.1 Salar de Uyuni Experiment
10.1.1 Phase errors
10.1.2 Phase multipath corrections
10.1.3 Effect of corrections on residuals and positions
10.2 TASH/KIT3 Network
10.2.1 SNR data
10.2.2 Phase multipath corrections
10.2.3 Phase errors and corrections
10.3 Discussion and Future Work
11 ConclusionsNuméro de notice : 14325 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse française Note de thèse : Thèse de doctorat : philosophy. department of aerospace engineering sciences : Boulder,University of Colorado : 2006 nature-HAL : Thèse DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=45244 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 14325-01 THESE Livre Centre de documentation Thèses Disponible Result from EO-1 experiment: a comparative study of earth observing-1 Advanced Land Imager (ALI) and Landsat ETM+ data for land cover mapping in the Okavango delta, Botswana / A.L. Neunschwander in International Journal of Remote Sensing IJRS, vol 26 n° 19 (October 2005)
[article]
Titre : Result from EO-1 experiment: a comparative study of earth observing-1 Advanced Land Imager (ALI) and Landsat ETM+ data for land cover mapping in the Okavango delta, Botswana Type de document : Article/Communication Auteurs : A.L. Neunschwander, Auteur ; Melba M. Crawford, Auteur ; S. Ringrose, Auteur Année de publication : 2005 Article en page(s) : pp 4321 - 4337 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse comparative
[Termes IGN] Botswana
[Termes IGN] carte d'occupation du sol
[Termes IGN] delta
[Termes IGN] géomorphologie locale
[Termes IGN] image EO1-ALI
[Termes IGN] image Landsat-ETM+
[Termes IGN] inondation
[Termes IGN] rapport signal sur bruitRésumé : (Auteur) The Earth Observing-1 (EO-1) satellite acquired a sequence of data in 2001 and 2002 that highlighted the annual flooding of the lower Okavango Delta. The data were collected as part of the calibration/validation programme for the Advanced Land Imager (ALI) sensor on the NASA EO-1 satellite. The primary purpose of this study was to compare the capability of ALI to that of Landsat ETM + for large-scale mapping applications in the Okavango Delta. While the extent and inaccessibility of many areas of the Delta make application of remote sensing attractive, the availability of data with adequate spatial and spectral resolution has limited the characterization of the complex patterns of land cover and geomorphology in the Delta. Initial analysis of the ALI data via supervised classification clearly showed macro-flood features, delineation of downstream channel flow areas, and lateral-downstream inundation of the floodplain. These patterns and the proportions of flooding of the channel compared to that of the floodplain (impoundment) varied annually, from the wetter seasonal swamps through the drier seasonal and occasional swamps. Consistently higher classification accuracies achieved using ALI data relative to ETM + data are attributed to the higher signal-to-noise ratio and the increased dynamic range of the ALI data. Numéro de notice : A2005-444 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160500112759 En ligne : https://doi.org/10.1080/01431160500112759 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27580
in International Journal of Remote Sensing IJRS > vol 26 n° 19 (October 2005) . - pp 4321 - 4337[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-05191 RAB Revue Centre de documentation En réserve L003 Exclu du prêt SPOT-4 Vegetation multi-temporal compositing for land cover change studies over tropical regions / João M.B. Carreiras in International Journal of Remote Sensing IJRS, vol 26 n° 7 (April 2005)
[article]
Titre : SPOT-4 Vegetation multi-temporal compositing for land cover change studies over tropical regions Type de document : Article/Communication Auteurs : João M.B. Carreiras, Auteur ; J.M.C. Pereira, Auteur Année de publication : 2005 Article en page(s) : pp 1323 - 1346 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse en composantes principales
[Termes IGN] autocorrélation spatiale
[Termes IGN] cohérence des données
[Termes IGN] détection de changement
[Termes IGN] filtrage du bruit
[Termes IGN] forêt tropicale
[Termes IGN] image multitemporelle
[Termes IGN] image optique
[Termes IGN] image SPOT-Végétation
[Termes IGN] Mato Grosso
[Termes IGN] nébulosité
[Termes IGN] rapport signal sur bruit
[Termes IGN] Soil Adjusted Vegetation Index
[Termes IGN] surveillance agricole
[Termes IGN] utilisation du sol
[Termes IGN] zone intertropicaleRésumé : (Auteur) Multi-temporal compositing of SPOT-4 VEGETATION imagery over tropical regions was tested to produce spatially coherent monthly composite images with reduced cloud contamination, for the year 2000. Monthly composite images generated from daily images (S1 product, 1-km) encompassing different land cover. types of the state of Mato Grosso, Brazil, were evaluated in terms of cloud contamination and spatial consistency. A new multi-temporal compositing algorithm was tested which uses different criteria for vegetated and non-vegetated or sparsely vegetated land cover types. Furthermore, a principal components transformation that rescales the noise in the image-Maximum Noise Fraction (MNF)- was applied to a multi-temporal dataset of monthly composite images and tested as a method of additional signal-to-noise ratio improvement. The back-transformed dataset using the first 12 MNF eigenimages yielded an accurate reconstruction of monthly composite images from the dry season (May to September) and enhanced spatial coherence from wet season images (October to April), as evaluated by the Moran's 1 index of spatial autocorrelation. This approach is useful for land cover- change studies in the tropics, where it is difficult to obtain cloud-free optical remote sensing imagery. In Mato Grosso, wet season composite images are important for monitoring agricultural crop cycles. Numéro de notice : A2005-178 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160512331338005 En ligne : https://doi.org/10.1080/01431160512331338005 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27315
in International Journal of Remote Sensing IJRS > vol 26 n° 7 (April 2005) . - pp 1323 - 1346[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-05071 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Effect of Jpeg2000 on the information and geometry content of aerial photo compression / J.K. Liu in Photogrammetric Engineering & Remote Sensing, PERS, vol 71 n° 2 (February 2005)PermalinkDécomposition de signaux aléatoires stationnaires et non-stationnaires / Philippe Courmontagne (2005)PermalinkFundamentals of radar signal processing / M. Richards (2005)PermalinkThéorie élémentaire du signal / Luc Jolivet (2005)PermalinkThe development of superspectral approaches for the improvement of land cover classification / M. Gianinetto in IEEE Transactions on geoscience and remote sensing, vol 42 n° 11 (November 2004)PermalinkSingle frequency processing of atmospheric radio occultations / M. De La Torre Juarez in International Journal of Remote Sensing IJRS, vol 25 n° 18 (September 2004)PermalinkThree-dimensional SAR imaging of a ground moving target using the INSAR technique / Qian Zhang in IEEE Transactions on geoscience and remote sensing, vol 42 n° 9 (October 2004)PermalinkGround penetrating radar, 2nd edition / D.J. Daniels (2004)PermalinkTraitement du signal et des images, 19e colloque GRETSI 2003, Paris, 8 au 11 septembre 2003, Tome 1. Actes 1 / Patrick Flandrin (2003)PermalinkTraitement du signal et des images, 19e colloque GRETSI 2003, Paris, 8 au 11 septembre 2003, Tome 2. Actes 2 / Patrick Flandrin (2003)PermalinkTraitement du signal et des images, 19e colloque GRETSI 2003, Paris, 8 au 11 septembre 2003, Tome 3. Actes 3 / Patrick Flandrin (2003)PermalinkUtilisation combinée des techniques GPS et radar / C. Hagin in XYZ, n° 93 (décembre 2002 - février 2003)PermalinkWide-angle airborne laser range data analysis for relative height determination of ground-based benchmarks / Olivier Bock in Journal of geodesy, vol 76 n° 6-7 (July 2002)PermalinkDetermination of thermal stratification and turbulence of the atmospheric surface layer over various types of terrain by optical scintillometry / Alexandra Weiss (2002)PermalinkExtraction 3D de structures industrielles par radargrammétrie haute-résolution / Elisabeth Simonetto in Bulletin [Société Française de Photogrammétrie et Télédétection], n° 166 (Janvier 2002)PermalinkGalileo and GPS, friends or foes / L. Tytgat in GPS world, vol 12 n° 9 (September 2001)PermalinkSub-cm subsidence measurements with the Wide-angle Airborne Laser ranging system / Olivier Bock in Surveys in Geophysics, vol 22 n° 5-6 (September 2001)PermalinkHochgenaue satellitengestützte Zeitübertragung mit PRARE / S. Bedrich (1998)PermalinkLasermessungen nach Erdsatelliten auf zwei Wellenlängen unter Verwendung einer Streak-Kamera / S. Riepl (1998)PermalinkOrtung von eindeutig identifizierbaren Zielen und kodierten Transpondern / D. Hounam (1998)Permalink