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GPS satellite differential code bias estimation with current eleven low earth orbit satellites / Xingxing Li in Journal of geodesy, vol 95 n° 7 (July 2021)
[article]
Titre : GPS satellite differential code bias estimation with current eleven low earth orbit satellites Type de document : Article/Communication Auteurs : Xingxing Li, Auteur ; Wei Zhang, Auteur ; Keke Zhang, Auteur Année de publication : 2021 Article en page(s) : n° 76 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] erreur systématique de code différentiel
[Termes IGN] orbite basse
[Termes IGN] précision de l'estimation
[Termes IGN] récepteur GPS
[Termes IGN] teneur verticale totale en électrons
[Termes IGN] trajet multipleRésumé : (auteur) Many low earth orbit (LEO) missions have been launched recently for different geoscience studying purposes such as ionosphere detecting and gravity recovering. The onboard observations from LEO satellites provide us a great opportunity to estimate the differential code bias (DCB) which is vital for precise applications of global navigation satellites system. This paper mainly focuses on the contribution of multi-LEO combination to the DCB estimation using onboard data collected by current eleven LEO satellites from day of year (DOY) 061, 2018 to DOY 120, 2018. The single-LEO solutions with different LEO and multi-LEO solutions with different LEO subsets are compared and analyzed in detail to fully exploit the potential of LEO onboard observations in the DCB estimation. We also evaluate and discuss the vertical total electron content (VTEC) results and posterior residuals to validate the estimation accuracy. Our results show that the average DCB standard deviation (STD) values are within 0.140 ns for all eleven single-LEO solutions with the best stability of 0.082 ns for Swarm-B solution. The evaluation of multi-LEO solutions indicates that with the increase in LEO satellites, the GPS DCB stability gets improved gradually. The 9-LEO solution can achieve the stability with STD value of 0.051 ns, better than that of DCB products from the German Aerospace Center (DLR) (0.055 ns) but slightly worse than that of DCB products from the Chinese Academy of Sciences (CAS) (0.048 ns). The results suggest that the GPS DCB stability based on the onboard observations of nine LEO satellites can be comparable to the ground-based solution derived from a global ground network with hundreds of stations. The LEO space-borne receiver DCB results illustrate that the inclusion of more LEO satellites can contribute to the stability improvement of receiver DCB. In addition, the VTEC estimation can benefit from the joint processing of multiple LEO observations and achieves a noticeable reduction in the percentage of negative VTEC values. Our results also reveal that the spherical symmetry ionosphere assumption might cause accuracy degradation in the DCB estimation at low latitudes. Numéro de notice : A2021-517 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-021-01536-2 Date de publication en ligne : 22/06/2021 En ligne : https://doi.org/10.1007/s00190-021-01536-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97939
in Journal of geodesy > vol 95 n° 7 (July 2021) . - n° 76[article]Comparison of polar ionospheric behavior at Arctic and Antarctic regions for improved satellite-based positioning / Arun Kumar Singh in Journal of applied geodesy, vol 15 n° 3 (July 2021)
[article]
Titre : Comparison of polar ionospheric behavior at Arctic and Antarctic regions for improved satellite-based positioning Type de document : Article/Communication Auteurs : Arun Kumar Singh, Auteur Année de publication : 2021 Article en page(s) : pp 269 - 277 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] amplitude
[Termes IGN] Antarctique
[Termes IGN] Arctique
[Termes IGN] champ géomagnétique
[Termes IGN] ionosphère
[Termes IGN] magnétosphère
[Termes IGN] phase
[Termes IGN] pôle
[Termes IGN] positionnement par GNSS
[Termes IGN] retard ionosphèrique
[Termes IGN] scintillation
[Termes IGN] teneur totale en électrons
[Termes IGN] variation temporelleRésumé : (Auteur) In this paper, we investigate the hemispheric symmetric and asymmetric characteristics of ionospheric total electron content (TEC) and its dependency on the interplanetary magnetic field (IMF) in the northern and southern polar ionosphere. The changes in amplitude and phase scintillation are also probed through Global Ionospheric Scintillation and TEC monitoring (GISTM) systems recordings at North pole [Himadri station; Geographic 78°55′ N, 11°56′ E] and South pole [Maitri station; Geographic 70°46′ S 11°44′ E]. Observations show the range of %TEC variability being relatively more over Antarctic region (−40 % to 60 %) than Arctic region (−25 % to 25 %), corroborating the role of the dominant solar photoionization production process. Our analysis confirms that TEC variation at polar latitudes is a function of magnetosphere-ionosphere coupling, depending on interplanetary magnetic field (IMF) orientation and magnitude in the X ( Bx), Y ( By), and Z ( Bz) plane. Visible enhancement in TEC is noticed in the northern polar latitude when Bx6nT and Bz>0 whereas the southern polar latitude perceives TEC enhancements with Bx>0, −6nT Numéro de notice : A2021-469 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1515/jag-2021-0033 Date de publication en ligne : 22/06/2021 En ligne : https://doi.org/10.1515/jag-2021-0033 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98107
in Journal of applied geodesy > vol 15 n° 3 (July 2021) . - pp 269 - 277[article]Evaluating the suitability of multi-scale terrain attribute calculation approaches for seabed mapping applications / Benjamin Misiuk in Marine geodesy, vol 44 n° 4 (July 2021)
[article]
Titre : Evaluating the suitability of multi-scale terrain attribute calculation approaches for seabed mapping applications Type de document : Article/Communication Auteurs : Benjamin Misiuk, Auteur ; Vincent Lecours, Auteur ; M.F.J. Dolan, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 327 - 385 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie thématique
[Termes IGN] analyse multiéchelle
[Termes IGN] artefact
[Termes IGN] attribut géomètrique
[Termes IGN] carte bathymétrique
[Termes IGN] cartographie hydrographique
[Termes IGN] fond marin
[Termes IGN] géomorphométrie
[Termes IGN] habitat animal
[Termes IGN] pente
[Termes IGN] réalité de terrain
[Termes IGN] rugosité
[Termes IGN] sondeur multifaisceaux
[Termes IGN] Terre-Neuve, île de (Terre-Neuve-et-Labrador)Résumé : (auteur) The scale dependence of benthic terrain attributes is well-accepted, and multi-scale methods are increasingly applied for benthic habitat mapping. There are, however, multiple ways to calculate terrain attributes at multiple scales, and the suitability of these approaches depends on the purpose of the analysis and data characteristics. There are currently few guidelines establishing the appropriateness of multi-scale raster calculation approaches for specific benthic habitat mapping applications. First, we identify three common purposes for calculating terrain attributes at multiple scales for benthic habitat mapping: (i) characterizing scale-specific terrain features, (ii) reducing data artefacts and errors, and (iii) reducing the mischaracterization of ground-truth data due to inaccurate sample positioning. We then define criteria that calculation approaches should fulfill to address these purposes. At two study sites, five raster terrain attributes, including measures of orientation, relative position, terrain variability, slope, and rugosity were calculated at multiple scales using four approaches to compare the suitability of the approaches for these three purposes. Results suggested that specific calculation approaches were better suited to certain tasks. A transferable parameter, termed the ‘analysis distance’, was necessary to compare attributes calculated using different approaches, and we emphasize the utility of such a parameter for facilitating the generalized comparison of terrain attributes across methods, sites, and scales. Numéro de notice : A2021-526 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/01490419.2021.1925789 Date de publication en ligne : 04/06/2021 En ligne : https://doi.org/10.1080/01490419.2021.1925789 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97967
in Marine geodesy > vol 44 n° 4 (July 2021) . - pp 327 - 385[article]Ionospheric irregularity layer height and thickness estimation with a GNSS receiver array / Seebany Datta-Barua in IEEE Transactions on geoscience and remote sensing, Vol 59 n° 7 (July 2021)
[article]
Titre : Ionospheric irregularity layer height and thickness estimation with a GNSS receiver array Type de document : Article/Communication Auteurs : Seebany Datta-Barua, Auteur ; Yang Su, Auteur ; Aurora López Rubio, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 6198 - 6207 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] Alaska (Etats-Unis)
[Termes IGN] hauteur de la couche ionosphérique
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] modèle ionosphérique
[Termes IGN] phase GNSS
[Termes IGN] rapport signal sur bruit
[Termes IGN] scintillation
[Termes IGN] série temporelle
[Termes IGN] signal GNSSRésumé : (auteur) This work develops a method by which a kilometer-spaced array of Global Navigation Satellite System (GNSS) scintillation receivers can be used to estimate the ionospheric irregularity layer height and thickness and associated uncertainties on those estimates. Spectra of filtered signal power and phase data are used to estimate these quantities by comparing the observed ratio of the log of the power spectrum to the phase spectrum with the Rytov weak scatter theoretical ratio. A Monte Carlo simulation of noise on the input signal and the irregularity drift velocity is used to quantify the error in estimates of height and thickness. The method is tested using data from the Scintillation Auroral Global Positioning System (GPS) Array (SAGA) sited in the auroral zone at Poker Flat Research Range, Alaska. For the 30-min scintillation period studied, the technique identifies ionospheric scattering from a thick F layer, which correlates well with on-site incoherent scatter radar measurements of peak electron density, for an event previously identified in the literature as likely due to F layer. Numéro de notice : A2021-539 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1109/TGRS.2020.3024173 Date de publication en ligne : 12/10/2020 En ligne : https://doi.org/10.1109/TGRS.2020.3024173 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98013
in IEEE Transactions on geoscience and remote sensing > Vol 59 n° 7 (July 2021) . - pp 6198 - 6207[article]Target-constrained interference-minimized band selection for hyperspectral target detection / Xiaodi Shang in IEEE Transactions on geoscience and remote sensing, Vol 59 n° 7 (July 2021)
[article]
Titre : Target-constrained interference-minimized band selection for hyperspectral target detection Type de document : Article/Communication Auteurs : Xiaodi Shang, Auteur ; Meiping Song, Auteur ; Yulei Wang, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 6044 - 6064 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande spectrale
[Termes IGN] détection de cible
[Termes IGN] image hyperspectrale
[Termes IGN] interférence
[Termes IGN] rapport signal sur bruitRésumé : (auteur) Wealthy spectral information provided by hyperspectral image (HSI) offers great benefits for many applications in hyperspectral data exploitation. However, processing such high-dimensional data volumes that may result in redundant bands due to its high interband correlation will be a challenge. For target detection and classification, this is particularly true since there may only need a relatively small number of bands that respond one particular target of interest well, while most of other bands do not. Band selection (BS) is a major dimensionality reduction technique to remove the redundant bands and selects a few bands to represent the entire image. However, how to eliminate the effect of uninteresting targets with similar spectra on detection of interesting targets is a severe issue arising in target detection for BS. This article develops a new approach called target-constrained interference-minimized BS (TCIMBS) which can be used to select band subset for specific target detection, while annihilating targets of no interest and suppressing interferers and background. Its idea is derived from target-constrained interference-minimized filter (TCIMF). By taking advantage of TCIMF, two band prioritization (BP) criteria called forward minimum variance BP (FMinV-BP) and backward maximum variance BP (BMaxV-BP) along with their three band search-based BS counterparts called sequential forward TCIMBS (SF-TCIMBS), sequential backward TCIMBS (SB-TCIMBS), and improved SB-TCIMBS (SB-TCIMBS*) are derived. The experimental results suggest that TCIMBS can improve the detection accuracy and also achieve better performance in comparison with several state-of-the-art methods. Numéro de notice : A2021-531 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2020.3010826 Date de publication en ligne : 26/08/2020 En ligne : https://doi.org/10.1109/TGRS.2020.3010826 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97987
in IEEE Transactions on geoscience and remote sensing > Vol 59 n° 7 (July 2021) . - pp 6044 - 6064[article]Trajectory and image-based detection and identification of UAV / Yicheng Liu in The Visual Computer, vol 37 n° 7 (July 2021)PermalinkAn automatic workflow for orientation of historical images with large radiometric and geometric differences / Ferdinand Maiwald in Photogrammetric record, vol 36 n° 174 (June 2021)PermalinkDeep learning in denoising of micro-computed tomography images of rock samples / Mikhail Sidorenko in Computers & geosciences, vol 151 (June 2021)PermalinkImpact of different sampling rates on precise point positioning performance using online processing service / Serdar Erol in Geo-spatial Information Science, vol 24 n° 2 (June 2021)PermalinkMulti-GNSS PPP/INS tightly coupled integration with atmospheric augmentation and its application in urban vehicle navigation / Shengfeng Gu in Journal of geodesy, vol 95 n° 6 (June 2021)PermalinkAn improved computerized ionospheric tomography model fusing 3-D multisource ionospheric data enabled quantifying the evolution of magnetic storm / Jian Kong in IEEE Transactions on geoscience and remote sensing, vol 59 n° 5 (May 2021)PermalinkSAR speckle removal using hybrid frequency modulations / Shuaiqi Liu in IEEE Transactions on geoscience and remote sensing, vol 59 n° 5 (May 2021)PermalinkSNR-based water height retrieval in rivers: Application to high amplitude asymmetric tides in the Garonne river / Pierre Zeiger in Remote sensing, vol 13 n° 9 (May-1 2021)PermalinkA stacked dense denoising–segmentation network for undersampled tomograms and knowledge transfer using synthetic tomograms / Dimitrios Bellos in Machine Vision and Applications, vol 32 n° 3 (May 2021)PermalinkUnsupervised multi-level feature extraction for improvement of hyperspectral classification / Qiaoqiao Sun in Remote sensing, vol 13 n° 8 (April-2 2021)PermalinkAtmospheric correction of Sentinel-3/OLCI data for mapping of suspended particulate matter and chlorophyll-a concentration in Belgian turbid coastal waters / Quinten Vanhellemont in Remote sensing of environment, Vol 256 (April 2020)PermalinkAutomatic atmospheric correction for shortwave hyperspectral remote sensing data using a time-dependent deep neural network / Jian Sun in ISPRS Journal of photogrammetry and remote sensing, vol 174 (April 2021)PermalinkDetecting ground deformation in the built environment using sparse satellite InSAR data with a convolutional neural network / Nantheera Anantrasirichai in IEEE Transactions on geoscience and remote sensing, vol 59 n° 4 (April 2021)PermalinkHyperspectral image denoising via clustering-based latent variable in variational Bayesian framework / Peyman Azimpour in IEEE Transactions on geoscience and remote sensing, vol 59 n° 4 (April 2021)PermalinkImpact of the third frequency GNSS pseudorange and carrier phase observations on rapid PPP convergences / Jiang Guo in GPS solutions, vol 25 n° 2 (April 2021)PermalinkApports de la télédétection des puits pastoraux à la cartographie des eaux souterraines du Sahel / Bernard Collignon in Revue Française de Photogrammétrie et de Télédétection, n° 223 (mars - décembre 2021)PermalinkEarly detection of forest stress from European spruce bark beetle attack, and a new vegetation index: Normalized distance red & SWIR (NDRS) / Langning Huo in Remote sensing of environment, Vol 255 (March 2021)PermalinkCluster-based empirical tropospheric corrections applied to InSAR time series analysis / Kyle Dennis Murray in IEEE Transactions on geoscience and remote sensing, Vol 59 n° 3 (March 2021)PermalinkDenoising Sentinel-1 extra-wide mode cross-polarization images over sea ice / Yan Sun in IEEE Transactions on geoscience and remote sensing, Vol 59 n° 3 (March 2021)PermalinkEnhanced trajectory estimation of mobile laser scanners using aerial images / Zille Hussnain in ISPRS Journal of photogrammetry and remote sensing, vol 173 (March 2021)Permalink