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Coastal GNSS-R phase altimetry based on the combination of L1 and L5 signals under high sea states / Yunqiao He in Journal of geodesy, vol 97 n° 2 (February 2023)
[article]
Titre : Coastal GNSS-R phase altimetry based on the combination of L1 and L5 signals under high sea states Type de document : Article/Communication Auteurs : Yunqiao He, Auteur ; Fan Gao, Auteur ; Tianhe Xu, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 19 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] diffusion de Rayleigh
[Termes IGN] hauteurs de mer
[Termes IGN] niveau de la mer
[Termes IGN] phase GNSS
[Termes IGN] précision altimétrique
[Termes IGN] Quasi-Zenith Satellite System
[Termes IGN] rapport signal sur bruit
[Termes IGN] récepteur bifréquence
[Termes IGN] réflectométrie par GNSS
[Termes IGN] signal GNSS
[Vedettes matières IGN] AltimétrieRésumé : (auteur) High-precision sea surface heights retrieved from the Global Navigation Satellite System Reflectometry (GNSS-R) measurements will be valuable in the fields of geodesy and oceanography studies. Due to the short wavelengths and low power of GNSS signals, the continuously tracked carrier phase measurements of reflected signals are usually unavailable for sea surfaces with big roughness, varying over space and time. In coastal conditions, persisting spatial coherence assumption can be made within the antenna coverage when the waves are not greatly breaking. To deal with temporal incoherence, we propose an improved algorithm to extract the combined interferometric phase difference measurements between direct and reflected signals under high sea states. After initial tracking the direct signals, dual-frequency observations are combined in the complex domain and the resulting interferometric signal is refined through open-loop tracking with 60-s coherent integration before the phase difference measurements are extracted, without tracking their respective carrier phase measurements in advance. In order to verify our method, a coastal experiment under different sea conditions was conducted and raw intermediate frequency data were collected. The raw data were then processed by a GNSS-R software-defined receiver to compute the path delay measurements of Quasi-Zenith Satellite System signals, which had good visibility during our experiment. For high sea states, that is, when the Rayleigh criterion is not fulfilled for the individual wavelengths, the phase delay measurements of L1 and L5 were random over time, while phase delay can still be well recovered for their combination. Also, the phase delay combination can be well extracted with a higher elevation angle than the previous studies. Finally, the altimetry solutions derived from the carrier phase delay measurements combination were compared with the in situ observations from a 26-GHz radar altimeter. The results show that centimeter-level altimetry accuracy using the combined measurements of L1 and L5 can be achieved under high sea states. Numéro de notice : A2023-132 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-023-01712-6 Date de publication en ligne : 27/03/2023 En ligne : https://doi.org/10.1007/s00190-023-01712-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102675
in Journal of geodesy > vol 97 n° 2 (February 2023) . - n° 19[article]Co-seismic ionospheric disturbances following the 2016 West Sumatra and 2018 Palu earthquakes from GPS and GLONASS measurements / Mokhamad Nur Cahyadi in Remote sensing, vol 14 n° 2 (January-2 2022)
[article]
Titre : Co-seismic ionospheric disturbances following the 2016 West Sumatra and 2018 Palu earthquakes from GPS and GLONASS measurements Type de document : Article/Communication Auteurs : Mokhamad Nur Cahyadi, Auteur ; Buldan Muslim, Auteur ; Danar Guruh Pratomo, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 401 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] déformation verticale de la croute terrestre
[Termes IGN] diffusion de Rayleigh
[Termes IGN] données GLONASS
[Termes IGN] données GNSS
[Termes IGN] Indonésie
[Termes IGN] onde acoustique
[Termes IGN] perturbation ionosphérique
[Termes IGN] propagation ionosphérique
[Termes IGN] séisme
[Termes IGN] Sumatra
[Termes IGN] teneur totale en électrons
[Termes IGN] tsunamiRésumé : (auteur) The study of ionospheric disturbances associated with the two large strike-slip earthquakes in Indonesia was investigated, which are West Sumatra on 2 March 2016 (Mw = 7.8), and Palu on 28 September 2018 (Mw = 7.5). The anomalies were observed by measuring co-seismic ionospheric disturbances (CIDs) using the Global Navigation Satellite System (GNSS). The results show positive and negative CIDs polarization changes for the 2016 West Sumatra earthquake, depending on the position of the satellite line-of-sight, while the 2018 Palu earthquake shows negative changes only due to differences in co-seismic vertical crustal displacement. The 2016 West Sumatra earthquake caused uplift and subsidence, while the 2018 Palu earthquake was dominated by subsidence. TEC anomalies occurred about 10 to 15 min after the two earthquakes with amplitude of 2.9 TECU and 0.4 TECU, respectively. The TEC anomaly amplitude was also affected by the magnitude of the earthquake moment. The disturbance signal propagated with a velocity of ~1–1.72 km s−1 for the 2016 West Sumatra earthquake and ~0.97–1.08 km s−1 for the 2018 Palu mainshock earthquake, which are consistent with acoustic waves. The wave also caused an oscillation signal of ∼4 mHz, and their azimuthal asymmetry of propagation confirmed the phenomena in the Southern Hemisphere. The CID signal could be identified at a distance of around 400–1500 km from the epicenter in the southwestern direction. Numéro de notice : A2022-103 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.3390/rs14020401 Date de publication en ligne : 16/01/2022 En ligne : https://doi.org/10.3390/rs14020401 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99571
in Remote sensing > vol 14 n° 2 (January-2 2022) . - n° 401[article]Sentinel-1 sensitivity to soil moisture at high incidence angle and the impact on retrieval over seasonal crops / Davide Palmisano in IEEE Transactions on geoscience and remote sensing, Vol 59 n° 9 (September 2021)
[article]
Titre : Sentinel-1 sensitivity to soil moisture at high incidence angle and the impact on retrieval over seasonal crops Type de document : Article/Communication Auteurs : Davide Palmisano, Auteur ; Francesco Mattia, Auteur ; Anna Balenzano, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 7308 - 7321 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] analyse de sensibilité
[Termes IGN] angle d'incidence
[Termes IGN] bande C
[Termes IGN] carte agricole
[Termes IGN] Castille-et-Leon (Espagne)
[Termes IGN] corrélation temporelle
[Termes IGN] cultures
[Termes IGN] humidité du sol
[Termes IGN] image Sentinel-SAR
[Termes IGN] Pouilles (Italie)
[Termes IGN] réseau hydrographique
[Termes IGN] rétrodiffusion
[Termes IGN] transfert radiatifRésumé : (auteur) Approximately, 30% of the Sentinel-1 (S-1) swath over land is imaged with incidence angles higher than 40°. Still, the interplay among the scattering mechanisms taking place at such a high incidence and their implications on the backscatter information content is often disregarded. This article investigates, through an experimental and numerical study, the S-1 sensitivity to the surface soil moisture (SSM) over agricultural fields observed at low (~33°) and high (~43°) incidence angles and quantifies the impact of the incidence angle on the SSM retrieval accuracy. The study sites are the Apulian Tavoliere (Italy) and REd de MEDición de la HUmedad del Suelo (REMEDHUS) (Spain), which are both instrumented with a hydrologic network continuously measuring SSM. At low incidence angles, results confirm that for crops such as wheat and barley, dominated in C-band by surface scattering, there exists a good sensitivity of S-1 VV to SSM. At high incidence angles, the sensitivity to SSM holds through the combination of the soil attenuated and double bounce scattering. Conversely, over crops dominated by volume scattering, such as sugar beet, the S-1 VV signal is not correlated with the in situ SSM observations, neither at low nor at high incidence. For all the crops, the sensitivity of S-1 to SSM in VH is found significantly lower than in VV. The impact of the incidence angle on the SSM retrieval has been studied with a recursive algorithm based on a short-term change detection approach. An upper and lower bounds for the worsening of the S-1 VV retrieval performance at far versus near range observations have been estimated. In the worst-case scenario, the root mean square error (RMSE) increases from ~0.056 m 3 /m 3 , at low incidence, to ~0.071 m 3 /m 3 , at high incidence. The mechanism that lowers the retrieval accuracy at high incidence angles is further investigated in the synthetic experiment and its impact on the RMSE is estimated in terms of the volume scattering contribution. Numéro de notice : A2021-646 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2020.3033887 Date de publication en ligne : 10/11/2020 En ligne : https://doi.org/10.1109/TGRS.2020.3033887 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98351
in IEEE Transactions on geoscience and remote sensing > Vol 59 n° 9 (September 2021) . - pp 7308 - 7321[article]Three-dimensional reconstruction of seismo-traveling ionospheric disturbances after March 11, 2011, Japan Tohoku earthquake / Changzhi Zhai in Journal of geodesy, vol 95 n° 7 (July 2021)
[article]
Titre : Three-dimensional reconstruction of seismo-traveling ionospheric disturbances after March 11, 2011, Japan Tohoku earthquake Type de document : Article/Communication Auteurs : Changzhi Zhai, Auteur ; Yibin Yao, Auteur ; Jian Kong, Auteur Année de publication : 2021 Article en page(s) : n° 77 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] diffusion de Rayleigh
[Termes IGN] GeoNet
[Termes IGN] modèle ionosphérique
[Termes IGN] onde acoustique
[Termes IGN] perturbation ionosphérique
[Termes IGN] reconstruction 3D
[Termes IGN] séisme
[Termes IGN] signal GPS
[Termes IGN] teneur totale en électrons
[Termes IGN] Tohoku (Japon)
[Termes IGN] tomographieRésumé : (auteur) The electron density structures of the seismo-traveling ionospheric disturbances (STIDs) during the Tohoku earthquake are reconstructed by applying the three-dimensional computerized ionospheric tomography (3DCIT) technique with a 30-s time resolution for the first time. The vertical distribution of 3DCIT results is consistent with the constellation observing system for meteorology, ionosphere and climate (COSMIC) observations. The horizontal speeds of STIDs at different altitudes are estimated, and the three types of STIDs related to Rayleigh waves, acoustic waves and gravity waves are identified by their propagation characters. The magnitude of STIDs related to Rayleigh waves decreased with altitude, and there was no significant difference between the speeds (~ 2500 m/s) at different altitudes. The STIDs caused by acoustic waves traveled faster at 300 km altitude (~ 666–724 m/s) than at 150 km altitude (~ 500–550 m/s). From 150 to 250 km altitudes, in the STIDs induced by gravity waves, the magnitude of positive and negative wave fronts showed the opposite trend. The speed at 300 km altitude (~ 332 m/s) was slightly larger than at 150 km altitude (~ 310 m/s). The Rayleigh waves related STIDs showed a conic-like geometry, whereas the acoustic waves and gravity waves induced STIDs showed inverted conic-like geometries. The possible propagation mechanisms of different types of STIDs are also discussed. Numéro de notice : A2021-524 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-021-01533-5 Date de publication en ligne : 23/06/2021 En ligne : https://doi.org/10.1007/s00190-021-01533-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97961
in Journal of geodesy > vol 95 n° 7 (July 2021) . - n° 77[article]Extraction of sea ice cover by Sentinel-1 SAR based on support vector machine with unsupervised generation of training data / Xiao-Ming Li in IEEE Transactions on geoscience and remote sensing, vol 59 n° 4 (April 2021)
[article]
Titre : Extraction of sea ice cover by Sentinel-1 SAR based on support vector machine with unsupervised generation of training data Type de document : Article/Communication Auteurs : Xiao-Ming Li, Auteur ; Yan Sun, Auteur ; Qiang Zhang, Auteur Année de publication : 2021 Article en page(s) : pp 3040 - 3053 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] Arctique, océan
[Termes IGN] classification non dirigée
[Termes IGN] classification par séparateurs à vaste marge
[Termes IGN] données d'entrainement (apprentissage automatique)
[Termes IGN] entropie
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] glace de mer
[Termes IGN] image radar moirée
[Termes IGN] image Sentinel-SAR
[Termes IGN] matrice de co-occurrence
[Termes IGN] niveau de gris (image)
[Termes IGN] polarisation croisée
[Termes IGN] rétrodiffusion
[Termes IGN] texture d'imageRésumé : (auteur) In this article, we focus on developing a novel method to extract sea ice cover (i.e., discrimination/classification of sea ice and open water) using Sentinel-1 (S1) cross-polarization [vertical–horizontal (VH) or horizontal–vertical (HV)] data in extra-wide (EW) swath mode based on the support vector machine (SVM) method. The classification basis includes the S1 radar backscatter and texture features, which are calculated from S1 data using the gray level co-occurrence matrix (GLCM). Different from previous methods where appropriate samples are manually selected to train the SVM to classify sea ice and open water, we proposed a method of unsupervised generation of the training samples based on two GLCM texture features, i.e., entropy and homogeneity, that have contrasting characteristics on sea ice and open water. We eliminate the most uncertainty of selecting training samples in machine learning and achieve automatic classification of sea ice and open water by using S1 EW data. The comparisons based on a few cases show good agreements between the synthetic aperture radar (SAR)-derived sea ice cover using the proposed method and visual inspections, of which the accuracy reaches approximately 90%–95%. Besides this, compared with the analyzed sea ice cover data Ice Mapping System (IMS) based on 728 S1 EW images, the accuracy of the extracted sea ice cover by using S1 data is more than 80%. Numéro de notice : A2021-284 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2020.3007789 Date de publication en ligne : 20/07/2020 En ligne : https://doi.org/10.1109/TGRS.2020.3007789 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97392
in IEEE Transactions on geoscience and remote sensing > vol 59 n° 4 (April 2021) . - pp 3040 - 3053[article]PermalinkMapping wetland using the object-based stacked generalization method based on multi-temporal optical and SAR data / Yaotong Cai in International journal of applied Earth observation and geoinformation, vol 92 (October 2020)PermalinkDeriving a frozen area fraction from Metop ASCAT backscatter based on Sentinel-1 / Helena Bergstedt in IEEE Transactions on geoscience and remote sensing, vol 58 n° 9 (September 2020)PermalinkDigital terrain, surface, and canopy height models from InSAR backscatter-height histograms / Gustavo H.X. Shiroma in IEEE Transactions on geoscience and remote sensing, vol 58 n° 6 (June 2020)PermalinkPotential of texture from SAR tomographic images for forest aboveground biomass estimation / Zhanmang Liao in International journal of applied Earth observation and geoinformation, vol 88 (June 2020)PermalinkWheat leaf area index retrieval using RISAT-1 hybrid polarized SAR data / Thota Sivasankar in Geocarto international, Vol 35 n° 8 ([01/06/2020])PermalinkImaging and diagnostic of sub-wavelength micro-structures, from closed-form algorithms to deep learning / Peipei Ran (2020)PermalinkManuel d'optique / Germain Chartier (2020)PermalinkIntegration of corner reflectors for the monitoring of mountain glacier areas with Sentinel-1 time series / Matthias Jauvin in Remote sensing, vol 11 n° 8 (August 2019)PermalinkPermalinkEstimation and mapping of above-ground biomass of mangrove forests and their replacement land uses in the Philippines using Sentinel imagery / Jose Alan A. Castillo in ISPRS Journal of photogrammetry and remote sensing, vol 134 (December 2017)PermalinkSingle image dehazing via an improved atmospheric scattering model / Mingye Ju in The Visual Computer, vol 33 n° 12 (December 2017)PermalinkCritical analysis of model-based incoherent polarimetric decomposition methods and investigation of deorientation effect / Pooja Mishra in IEEE Transactions on geoscience and remote sensing, vol 55 n° 9 (September 2017)PermalinkA time-series approach to estimating soil moisture from vegetated surfaces using L-band radar backscatter / Jeffrey D. Ouellette in IEEE Transactions on geoscience and remote sensing, vol 55 n° 6 (June 2017)PermalinkMise en place d'une méthode semi-automatique de cartographie de l'occupation des sols à partir d'images SAR polarimétriques / Monique Moine in Revue Française de Photogrammétrie et de Télédétection, n° 215 (mai - août 2017)PermalinkUrban damage level mapping based on scattering mechanism investigation using fully polarimetric SAR Data for the 3.11 East Japan earthquake / Si-Wei Chen in IEEE Transactions on geoscience and remote sensing, vol 54 n° 12 (December 2016)PermalinkGeneralized terrain topography in radar scattering models / Mariko S. Burgin in IEEE Transactions on geoscience and remote sensing, vol 54 n° 7 (July 2016)PermalinkPassive 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)PermalinkPermalinkA fast classification scheme in Raman spectroscopy for the identification of mineral mixtures using a large database with correlated predictors / Corey J. Cochrane in IEEE Transactions on geoscience and remote sensing, vol 53 n° 8 (August 2015)PermalinkUnderstanding the effects of ALS pulse density for metric retrieval across diverse forest types / Phil Wilkes in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 8 (August 2015)PermalinkNon-invasive forest litter characterization using full-wave inversion of microwave radar data / Frédéric André in IEEE Transactions on geoscience and remote sensing, vol 53 n° 2 (February 2015)PermalinkModelling electrical conductivity of soil from backscattering coefficient of microwave remotely sensed data using artificial neural network / Walaiporn Phonphan in Geocarto international, vol 29 n° 7 - 8 (November - December 2014)PermalinkMeasurements of forest biomass change using P-Band synthetic aperture radar backscatter / Gustaf Sandberg in IEEE Transactions on geoscience and remote sensing, vol 52 n° 10 tome 1 (October 2014)PermalinkOn the SAR backscatter of burned forests: a model-based study in C-Band, over burned pine canopies full text / Vasileios kalogirou in IEEE Transactions on geoscience and remote sensing, vol 52 n° 10 tome 1 (October 2014)PermalinkA novel rapid SAR simulator based on equivalent scatterers for three-dimensional forest canopies / Tao Zeng in IEEE Transactions on geoscience and remote sensing, vol 52 n° 9 Tome 1 (September 2014)PermalinkBackscattering of individual LiDAR pulses from forest canopies explained by photogrammetrically derived vegetation structure / Ilkka Korpela in ISPRS Journal of photogrammetry and remote sensing, vol 83 (September 2013)PermalinkRetrieval of tropical forest biomass information from ALOS PALSAR data / Mahmudur Rahman in Geocarto international, vol 28 n° 5-6 (August - October 2013)PermalinkPolarization scatterer feature metric space / William L. Cameron in IEEE Transactions on geoscience and remote sensing, vol 51 n° 6 Tome 2 (June 2013)PermalinkSoil moisture estimation under low vegetation cover using a multi-angular polarimetric decomposition / Thomas Jaghuber in IEEE Transactions on geoscience and remote sensing, vol 51 n° 4 Tome 2 (April 2013)PermalinkA proposed framework to unmix scattering mechanisms of polarimetric radar images using very high resolution optical images / Sébastien Giordano in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol I-7 (2012)PermalinkTesting a near-infrared Lidar mounted with a large incidence angle to monitor the water level of turbid reservoirs / S. Tamari in ISPRS Journal of photogrammetry and remote sensing, vol 66 n° 6 supplement (December 2011)PermalinkRadar backscatter mapping using TerraSAR-X / P. Rizzoli in IEEE Transactions on geoscience and remote sensing, vol 49 n° 10 Tome 1 (October 2011)PermalinkEffect of corn on C-an L-band radar backscatter: a correction method for soil moisture retrieval / A. Joseph in Remote sensing of environment, vol 114 n° 11 (15/11/2010)PermalinkFriendly reflections: monitoring water level with GNSS / A. Egido in GPS world, vol 21 n° 9 (September 2010)PermalinkSnow permitivity retrieval inversion algorithm for estimating snow wetness / G. Singh in Geocarto international, vol 25 n° 3 (June 2010)PermalinkA case study of using Raman lidar measurements in high-accuracy GPS applications / Pierre Bosser in Journal of geodesy, vol 84 n° 4 (April 2010)PermalinkDiscrimination of agricultural crops in a tropical semi-arid region of Brazil based on L-band polarimetric airborne SAR data / W. Silva in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 5 (September - October 2009)PermalinkPotentiality of feed-forward neural networks for classifying dark formations to oil spills and look-alikes / Konstantinos Topouzelis in Geocarto international, vol 24 n° 3 (June - July 2009)PermalinkRadiometric Calibration of LIDAR Intensity With Commercially Available Reference Targets / S. Kaasalainen in IEEE Transactions on geoscience and remote sensing, vol 47 n° 2 (February 2009)PermalinkFull-waveform topographic lidar: State-of-the-art / Frédéric Bretar in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 1 (January - February 2009)PermalinkRetrieval of surface roughness using multi-polarized Envisat-1 ASAR data / H.s Srivastava in Geocarto international, vol 23 n° 1 (February - March 2008)PermalinkDéveloppement et validation d'une méthode de calcul GPS intégrant des mesures de profils de vapeur d'eau en visée multi-angulaire pour l'altimétrie de haute précision / Pierre Bosser (2008)PermalinkEléments de physique pour l'imagerie aérienne et spatiale et la géodésie [diaporama pour le master PPMD] / Michel Kasser (2008)PermalinkLidar et applications en géophysique externe / P.H. Flamant in Revue Française de Photogrammétrie et de Télédétection, n° 186 (Juin 2007)Permalink