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A new method for specular and diffuse pseudorange multipath error extraction using wavelet analysis / Giovanni Pugliano in GPS solutions, vol 20 n° 3 (July 2016)
[article]
Titre : A new method for specular and diffuse pseudorange multipath error extraction using wavelet analysis Type de document : Article/Communication Auteurs : Giovanni Pugliano, Auteur ; Umberto Robustelli, Auteur ; Fabio Rossi, Auteur ; Raffaele Santamaria, Auteur Année de publication : 2016 Article en page(s) : pp 499 - 508 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Campanie (Italie)
[Termes IGN] correction du trajet multiple
[Termes IGN] mesurage de pseudo-distance
[Termes IGN] onde porteuse
[Termes IGN] réflexion spéculaire
[Termes IGN] transformation en ondelettes
[Vedettes matières IGN] Traitement de données GNSSRésumé : (Auteur) Multipath remains one of the major challenges in Global Navigation Satellite System (GNSS) positioning because it is considered the dominant source of ranging errors, which can be classified into specular and diffuse types. We present a new method using wavelets to extract the pseudorange multipath in the time domain and breaking it down into the two components. The main idea is an analysis-reconstruction approach based on application of both continuous wavelet transform (CWT) and discrete wavelet transform (DWT). The proposed procedure involves the use of L1 code-minus-carrier (CMC) observable where higher-frequency terms are isolated as residuals. CMC residuals are analyzed by applying the CWT, and we propose the scalogram as a technique for discerning time–frequency variations of the multipath signal. Unlike Fourier transform, the potential of the CWT scalogram for examining the non-stationary and multifrequency nature of the multipath is confirmed as it simultaneously allows fine detection and time localization of the most representative frequencies of the signal. This interpretation of the CWT scalogram is relevant when choosing the levels of reconstruction with DWT, allowing accurate time domain extraction of both the specular and diffuse multipath. The performance and robustness of the method and its boundary applicability are assessed. The experiment was carried out using a receiver of Campania GNSS Network. The results are given in which specular multipath error is achieved using DWT level 7 approximation component and diffuse multipath error is achieved using DWT level 6 denoised detail component. Numéro de notice : A2016-634 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-015-0458-0 En ligne : http://dx.doi.org/10.1007/s10291-015-0458-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81838
in GPS solutions > vol 20 n° 3 (July 2016) . - pp 499 - 508[article]Range imaging of E-region field-aligned irregularities by using a multifrequency technique : validation and initial results / Jenn-Shyong Chen in IEEE Transactions on geoscience and remote sensing, vol 54 n° 7 (July 2016)
[article]
Titre : Range imaging of E-region field-aligned irregularities by using a multifrequency technique : validation and initial results Type de document : Article/Communication Auteurs : Jenn-Shyong Chen, Auteur ; Yen-Hsyang Chu, Auteur ; Ching-Lun Su, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 3739 - 3749 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] étalonnage d'instrument
[Termes IGN] fréquence multiple
[Termes IGN] ionosphère
[Termes IGN] onde métrique
[Termes IGN] radar imageurRésumé : (Auteur) This paper reports the first use of a multifrequency range imaging (RIM) technique for observing E-region field-aligned irregularities (FAIs) in the midlatitude ionosphere. The Middle and Upper atmosphere Radar (MUR; 34.85°N, 136.10°E) was used to conduct experiments with five equally spaced frequencies between 46.25 and 46.75 MHz. Three types of RIM data were examined: data with 13-element binary Barker codes, with 16-element binary complementary codes, and without phase codes. Moreover, two calibration approaches were adopted to validate the applicability of the RIM technique, which functioned as intended. Excellent RIM performance such as the ability to resolve several striations in an echo region of FAIs was demonstrated. However, sidelobe echoes caused by pulse coding mechanisms were occasionally observed at altitudes above and below the source regions in the coded data. Therefore, a procedure was developed according to one of the calibration approaches to identify and remove such kind of sidelobe echoes, which was shown to be applicable for the complementary-coded data. In addition to FAIs, a thin plasma layer with a thickness of approximately 1 km was identified as being structured with some tilted finer structures, which could not be observed in the original intensity images with a range resolution of 600 m. Preliminary estimates of the Doppler velocities indicated that a wind shear effect could be the cause of such tilted finer structures. Numéro de notice : A2016-870 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2016.2521702 En ligne : http://dx.doi.org/10.1109/TGRS.2016.2521702 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83027
in IEEE Transactions on geoscience and remote sensing > vol 54 n° 7 (July 2016) . - pp 3739 - 3749[article]Characterization of ionospheric variability in TEC using EOF and wavelets over low-latitude GNSS stations / J.R.K. Kumar Dabbakuti in Advances in space research, vol 57 n° 12 (June 2016)
[article]
Titre : Characterization of ionospheric variability in TEC using EOF and wavelets over low-latitude GNSS stations Type de document : Article/Communication Auteurs : J.R.K. Kumar Dabbakuti, Auteur ; D. Venkata Ratman, Auteur Année de publication : 2016 Article en page(s) : pp 2427 – 2443 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] coordonnées GPS
[Termes IGN] fonction orthogonale
[Termes IGN] International Reference Ionosphere
[Termes IGN] retard ionosphèrique
[Termes IGN] teneur totale en électrons
[Termes IGN] transformation en ondelettesRésumé : (auteur) Investigation of ionospheric variability is essential for improving the daily ionospheric modeling and forecasting services of Global Navigation Satellite System (GNSS) applications. As India is a low-latitude region, more care has to be taken here to characterize the ionosphere due to irregularities and Equatorial Ionization Anomaly (EIA) conditions. Therefore, an appropriate method is required to diagnose the ionospheric variations during geomagnetic, solar and other disturbances. In this paper, the temporal ionospheric time delay variations were studied based on the Empirical Orthogonal Function (EOF) analysis and wavelet transforms (WT).These analyses were carried out with Total Electron Content (TEC) datasets obtained from three GNSS stations located in low-latitude regions. EOF analysis was performed on the TEC datasets, which were decomposed into a time series of orthogonal eigen values (or base functions) and associated coefficients. EOF base functions and their associated coefficients signify the hourly time variations and the day of the year variations. The results reveal that the first few EOFs represented the majority of TEC variability pertaining to the physical processes of the ionosphere. The accuracy of the EOF model was validated by the evaluation of observational TEC data with International Reference Ionosphere (IRI) 2012 models. The EOF model coefficients for each GNSS station showed a strong correlation with the IRI models and also described the correlation between the impacts of the level of geomagnetic activity on the ionosphere. The correlation coefficients for the first three EOFs were more than 0.95. The phase relationship of ionospheric TEC anomalies, with respect to the geomagnetic indices (Dst), were analyzed by wavelet transforms. Numéro de notice : A2016-267 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2016.03.029 En ligne : https://doi.org/10.1016/j.asr.2016.03.029 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80802
in Advances in space research > vol 57 n° 12 (June 2016) . - pp 2427 – 2443[article]Spectral band selection for urban material classification using hyperspectral libraries / Arnaud Le Bris in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol III-7 (July 2016)
[article]
Titre : Spectral band selection for urban material classification using hyperspectral libraries Type de document : Article/Communication Auteurs : Arnaud Le Bris , Auteur ; Nesrine Chehata , Auteur ; Xavier Briottet , Auteur ; Nicolas Paparoditis , Auteur Année de publication : 2016 Article en page(s) : pp 33 - 40 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] bande spectrale
[Termes IGN] base de données d'images
[Termes IGN] capteur superspectral
[Termes IGN] classification par forêts d'arbres décisionnels
[Termes IGN] classification par séparateurs à vaste marge
[Termes IGN] image aérienne
[Termes IGN] image hyperspectrale
[Termes IGN] milieu urbain
[Termes IGN] optimisation (mathématiques)
[Termes IGN] rayonnement infrarouge
[Termes IGN] signature spectraleRésumé : (auteur) In urban areas, information concerning very high resolution land cover and especially material maps are necessary for several city modelling or monitoring applications. That is to say, knowledge concerning the roofing materials or the different kinds of ground areas is required. Airborne remote sensing techniques appear to be convenient for providing such information at a large scale. However, results obtained using most traditional processing methods based on usual red-green-blue-near infrared multispectral images remain limited for such applications. A possible way to improve classification results is to enhance the imagery spectral resolution using superspectral or hyperspectral sensors. In this study, it is intended to design a superspectral sensor dedicated to urban materials classification and this work particularly focused on the selection of the optimal spectral band subsets for such sensor. First, reflectance spectral signatures of urban materials were collected from 7 spectral libraires. Then, spectral optimization was performed using this data set. The band selection workflow included two steps, optimising first the number of spectral bands using an incremental method and then examining several possible optimised band subsets using a stochastic algorithm. The same wrapper relevance criterion relying on a confidence measure of Random Forests classifier was used at both steps. To cope with the limited number of available spectra for several classes, additional synthetic spectra were generated from the collection of reference spectra: intra-class variability was simulated by multiplying reference spectra by a random coefficient. At the end, selected band subsets were evaluated considering the classification quality reached using a rbf svm classifier. It was confirmed that a limited band subset was sufficient to classify common urban materials. The important contribution of bands from the Short Wave Infra-Red (SWIR) spectral domain (1000–2400 nm) to material classification was also shown. Numéro de notice : A2016-825 Affiliation des auteurs : LASTIG MATIS+Ext (2012-2019) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.5194/isprs-annals-III-7-33-2016 Date de publication en ligne : 07/06/2016 En ligne : http://dx.doi.org/10.5194/isprs-annals-III-7-33-2016 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82695
in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences > vol III-7 (July 2016) . - pp 33 - 40[article]Hybrid online mobile laser scanner calibration through image alignment by mutual information / Mourad Miled in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol III-1 (July 2016)
[article]
Titre : Hybrid online mobile laser scanner calibration through image alignment by mutual information Type de document : Article/Communication Auteurs : Mourad Miled, Auteur ; Bahman Soheilian , Auteur ; Emmanuel Habets , Auteur ; Bruno Vallet , Auteur Année de publication : 2016 Projets : 1-Pas de projet / Conférence : ISPRS 2016, Commission 3, 23th international congress 12/07/2016 19/07/2016 Prague République tchèque ISPRS OA Annals Commission 3 Article en page(s) : pp 25 - 31 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] étalonnage en vol
[Termes IGN] Lidar
[Termes IGN] luminance lumineuse
[Termes IGN] réflectance
[Termes IGN] semis de points
[Termes IGN] système de numérisation mobileRésumé : (auteur) This paper proposes an hybrid online calibration method for a laser scanner mounted on a mobile platform also equipped with an imaging system. The method relies on finding the calibration parameters that best align the acquired points cloud to the images. The quality of this intermodal alignment is measured by Mutual information between image luminance and points reflectance. The main advantage and motivation is ensuring pixel accurate alignment of images and point clouds acquired simultaneously, but it is also much more flexible than traditional laser calibration methods. Numéro de notice : A2016-819 Affiliation des auteurs : LASTIG MATIS (2012-2019) Autre URL associée : vers HAL Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.5194/isprs-annals-III-1-25-2016 Date de publication en ligne : 01/06/2016 En ligne : http://dx.doi.org/10.5194/isprs-annals-III-1-25-2016 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82623
in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences > vol III-1 (July 2016) . - pp 25 - 31[article]An interactive tool for semi-automatic feature extraction of hyperspectral data / Zoltan Kovacs in Open geosciences, vol 8 n° 1 (January - July 2016)PermalinkCorrection of atmospheric refraction geolocation error for high resolution optical satellite pushbroom images / Ming Yan in Photogrammetric Engineering & Remote Sensing, PERS, vol 82 n° 6 (June 2016)PermalinkA spectral–structural bag-of-features scene classifier for very high spatial resolution remote sensing imagery / Bei Zhao in ISPRS Journal of photogrammetry and remote sensing, vol 116 (June 2016)PermalinkExploiting joint sparsity for pansharpening : the J-SparseFI algorithm / Xiao Xiang Zhu in IEEE Transactions on geoscience and remote sensing, vol 54 n° 5 (May 2016)PermalinkGlobal sensitivity analysis of the L-MEB model for retrieving soil moisture / Zengyan Wang in IEEE Transactions on geoscience and remote sensing, vol 54 n° 5 (May 2016)PermalinkGLORI: A GNSS-R Dual Polarization Airborne Instrument for Land Surface Monitoring / Erwan Motte in Sensors, vol 16 n° 5 (May 2016)PermalinkMultisensor and multispectral Lidar characterization and classification of a forest environment / Christopher Hopkinson in Canadian journal of remote sensing, vol 42 n° 5 ([01/05/2016])PermalinkRemote sensing of alpine glaciers in visible and infrared wavelengths: a survey of advances and prospects / Anshuman Bhardwaj in Geocarto international, vol 31 n° 5 - 6 (May - June 2016)PermalinkStorm event representation and analysis based on a directed spatiotemporal graph model / W. Liu in International journal of geographical information science IJGIS, vol 30 n° 5-6 (May - June 2016)PermalinkComparative analysis of real-time precise point positioning zenith total delay estimates / F.A. Ahmed in GPS solutions, vol 20 n° 2 (April 2016)PermalinkForest above ground biomass inversion by fusing GLAS with optical remote sensing data / Xiaohuan Xi in ISPRS International journal of geo-information, vol 5 n° 4 (April 2016)PermalinkThe attenuation of retroreflective signatures on surface soils / Robyn A. Barbato in Photogrammetric Engineering & Remote Sensing, PERS, vol 82 n° 4 (April 2016)Permalink14 years of GPS tropospheric delays in the French–Italian border region : comparisons and first application in a case study / Domenico Sguerso in Applied geomatics, vol 8 n° 1 (March 2016)PermalinkCorrection of terrestrial LiDAR intensity channel using Oren–Nayar reflectance model: An application to lithological differentiation / Dario Carrea in ISPRS Journal of photogrammetry and remote sensing, vol 113 (March 2016)PermalinkDetermination of differential code biases with multi-GNSS observations / Ningbo Wang in Journal of geodesy, vol 90 n° 3 (March 2016)PermalinkEffect of tree location on mitigating parking lot insolation / Ivana Bajsanski in Computers, Environment and Urban Systems, vol 56 (March 2016)PermalinkNoise simulation and correction in synthetic airborne TIR Data for mineral quantification / Christoph Hecker in IEEE Transactions on geoscience and remote sensing, vol 54 n° 3 (March 2016)PermalinkToward operational compensation of ionospheric effects in SAR interferograms: the split-spectrum method / Giorgio Gomba in IEEE Transactions on geoscience and remote sensing, vol 54 n° 3 (March 2016)PermalinkAn enhanced algorithm to estimate BDS satellite’s differential code biases / Chuang Shi in Journal of geodesy, vol 90 n° 2 (February 2016)PermalinkIonospheric corrections for single-frequency tracking of GNSS satellites by VLBI based on co-located GNSS / Benjamin Männel in Journal of geodesy, vol 90 n° 2 (February 2016)PermalinkIs waveform worth it? A comparison of LiDAR approaches for vegetation and landscape characterization / Karen Anderson in Remote sensing in ecology and conservation, vol 2 n° 1 (February 2016)PermalinkA wavelet-based echo detector for waveform LiDAR data / Cheng-Kai Wang in IEEE Transactions on geoscience and remote sensing, vol 54 n° 2 (February 2016)PermalinkPermalinkAirborne DLSLA 3-D SAR image reconstruction by combination of polar formatting and L_1 regularization / Xueming Peng in IEEE Transactions on geoscience and remote sensing, vol 54 n° 1 (January 2016)PermalinkApport de la télédétection radar satellitaire pour la cartographie de la forêt des Landes / Yousra Hamrouni (2016)PermalinkAssessment of forest canopy vertical structure with multi - scale remote sensing : from the plot to the large area / Phil Wilkes (2016)PermalinkPermalinkCompressive sensing for multibaseline polarimetric SAR tomography of forested areas / Xinwu Li in IEEE Transactions on geoscience and remote sensing, vol 54 n° 1 (January 2016)PermalinkContributions à la segmentation non supervisée d'images hyperspectrales : trois approches algébriques et géométriques / Saadallah El Asmar (2016)PermalinkCorrection troposphérique des interférogrammes issus d’images radar par mesures GNSS et modèle global d’atmosphère / Vincent Dubreuil (2016)PermalinkPermalinkDigital surface model generation over urban areas using high resolution satellite SAR imagery : tomographic techniques and their application to 3-Dchange monitoring / Martina Porfiri (2016)PermalinkEffectiveness of observation-domain sidereal filtering for GPS precise point positioning / Christopher Atkins in GPS solutions, vol 20 n° 1 (January 2016)PermalinkEntwicklung einer direkten Georeferenzierungseinheit zur Positions- und Orientierungbestimmung leichter UAVs in Eichzeit / Christian Eling (2016)PermalinkExternal error modelling with combined model in terrestrial laser scanning / J. Wang in Survey review, vol 48 n° 346 (January 2016)PermalinkForcing scale invariance in multipolarization SAR change detection / Vincenzo Carotenuto in IEEE Transactions on geoscience and remote sensing, vol 54 n° 1 (January 2016)PermalinkPermalinkPermalinkPassive microwave remote sensing of soil moisture based on dynamic vegetation scattering properties for AMSR-E / Jinyang Du in IEEE Transactions on geoscience and remote sensing, vol 54 n° 1 (January 2016)PermalinkPermalinkRadar based classification prior to biomass retrieval from P-Band SAR data / Pierre-Louis Frison (2016)PermalinkRemote Sensing Observations of Continental Surfaces, ch. 6. Airborne lidar data processing / Clément Mallet (2016)PermalinkStatic GNSS precise point positioning using free online services for Africa / Anis Abdallah in Survey review, vol 48 n° 346 (January 2016)PermalinkPermalinkTraitement du signal marégraphique par analyse harmonique pour la détermination d'une référence altimétrique pour l'Algérie / A. Rami in Bulletin des sciences géographiques, n° 30 (2015 - 2016)Permalink