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Analysis of ocean tide loading displacements by GPS kinematic precise point positioning: a case study at the China coastal site SHAO / H. Zhao in Survey review, vol 51 n° 365 (March 2019)
[article]
Titre : Analysis of ocean tide loading displacements by GPS kinematic precise point positioning: a case study at the China coastal site SHAO Type de document : Article/Communication Auteurs : H. Zhao, Auteur ; Q. Zhang, Auteur ; R. Tu, Auteur ; Z. Liu, Auteur Année de publication : 2019 Article en page(s) : pp 172 - 182 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] analyse spectrale
[Termes IGN] Chine
[Termes IGN] données GPS
[Termes IGN] données marégraphiques
[Termes IGN] GPS en mode cinématique
[Termes IGN] littoral
[Termes IGN] marée océanique
[Termes IGN] positionnement ponctuel précis
[Termes IGN] série temporelle
[Termes IGN] surcharge océaniqueRésumé : (Auteur) Ocean tide loading (OTL) displacement amplitudes and phase lags of SHAO site are estimated by global positioning system (GPS), kinematic precise point positioning (PPP) and spectral analysis using 19 years of continuous GPS observations. In kinematic PPP, the 66 additional harmonic displacement parameters are replaced by the three time-varying displacement parameters without a priori modelled OTL displacements. By comparing the results with predictions from hybrid regional/global models, we are able to demonstrate that GPS/model agreements are at the level of 0.2 mm (horizontal) and 0.6 mm (vertical) for the four lunar constituents, 0.4 mm (horizontal) and 1.35 mm (vertical) for the four solar/sidereal constituents, and 0.2 mm (horizontal) and 0.3 mm (vertical) for the three long-period constituents. Finally, we conclude that GPS-derived lunar constituents can substitute for the model corrections in GPS data processing and the accuracy of GPS-derived solar/sidereal constituents needs to be improved by further studies. Numéro de notice : A2019-190 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2017.1407392 Date de publication en ligne : 30/11/2017 En ligne : https://doi.org/10.1080/00396265.2017.1407392 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92634
in Survey review > vol 51 n° 365 (March 2019) . - pp 172 - 182[article]Calibration errors in determining slant Total Electron Content (TEC) from multi-GNSS data / Wei Li in Advances in space research, vol 63 n° 5 (1 March 2019)
[article]
Titre : Calibration errors in determining slant Total Electron Content (TEC) from multi-GNSS data Type de document : Article/Communication Auteurs : Wei Li, Auteur ; Guangxing Wang, Auteur ; Jinzhong Mi, Auteur ; Shaocheng Zhang, Auteur Année de publication : 2019 Article en page(s) : pp 1670 - 1680 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] données BeiDou
[Termes IGN] données Galileo
[Termes IGN] données GNSS
[Termes IGN] données GPS
[Termes IGN] étalonnage des données
[Termes IGN] ligne de base
[Termes IGN] propagation ionosphérique
[Termes IGN] simple différence
[Termes IGN] teneur totale en électrons
[Termes IGN] trajet multipleRésumé : (Auteur) The global navigation satellite system (GNSS) is presently a powerful tool for sensing the Earth's ionosphere. For this purpose, the ionospheric measurements (IMs), which are by definition slant total electron content biased by satellite and receiver differential code biases (DCBs), need to be first extracted from GNSS data and then used as inputs for further ionospheric representations such as tomography. By using the customary phase-to-code leveling procedure, this research comparatively evaluates the calibration errors on experimental IMs obtained from three GNSS, namely the US Global Positioning System (GPS), the Chinese BeiDou Navigation Satellite System (BDS), and the European Galileo. On the basis of ten days of dual-frequency, triple-GNSS observations collected from eight co-located ground receivers that independently form short-baselines and zero-baselines, the IMs are determined for each receiver for all tracked satellites and then for each satellite differenced for each baseline to evaluate their calibration errors. As first derived from the short-baseline analysis, the effects of calibration errors on IMs range, in total electron content units, from 1.58 to 2.16, 0.70 to 1.87, and 1.13 to 1.56 for GPS, Galileo, and BDS, respectively. Additionally, for short-baseline experiment, it is shown that the code multipath effect accounts for their main budget. Sidereal periodicity is found in single-differenced (SD) IMs for GPS and BDS geostationary satellites, and the correlation of SD IMs over two consecutive days achieves the maximum value when the time tag is around 4 min. Moreover, as byproducts of zero-baseline analysis, daily between-receiver DCBs for GPS are subject to more significant intra-day variations than those for BDS and Galileo. Numéro de notice : A2019-172 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2018.11.020 Date de publication en ligne : 05/12/2018 En ligne : https://doi.org/10.1016/j.asr.2018.11.020 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92624
in Advances in space research > vol 63 n° 5 (1 March 2019) . - pp 1670 - 1680[article]GNSS ionospheric TEC and positioning accuracy during intense space and terrestrial weather events in B&H / Randa Natraš in Geodetski vestnik, vol 63 n° 1 (March - May 2019)
[article]
Titre : GNSS ionospheric TEC and positioning accuracy during intense space and terrestrial weather events in B&H Type de document : Article/Communication Auteurs : Randa Natraš, Auteur ; Dževad Krdžalić, Auteur ; Džana Horozović, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 73 - 91 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] Bosnie-Herzégovine
[Termes IGN] ionosphère
[Termes IGN] neige
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] positionnement statique
[Termes IGN] précision du positionnement
[Termes IGN] tempête magnétique
[Termes IGN] teneur totale en électrons
[Termes IGN] troposphèreRésumé : (Auteur) To achieve the high accuracy in GNSS positioning, the various atmospheric effects on GNSS signals need to be mitigated, where the major part present the ionised atmosphere (ionosphere) and the neutral atmosphere (troposphere). Additional signal scattering can occur from heavy precipitation and from snow accumulation on the antenna and on its surroundings. In this study, irregularities in the ionosphere induced by space weather were analysed, as well as sudden snowfall with its impact on meteorological conditions in the troposphere. State in the ionosphere was characterised by total electron content (TEC) derived from GNSS observation of EUREF Permanent Network (EPN) station SRJV in Bosnia and Herzegovina (B&H). Their impacts on the accuracy of GNSS positioning of the EPN station SRJV were examined by applying post-processing static PPP and network solutions using several software (the open-source and commercial). The study period was March 2015, when the strongest geomagnetic storm of solar cycle 24 (St. Patrick’s Day, March 17) and sudden intense snowfall (beginning of the month) occurred. Ionospheric TEC deviated for more than 20 TECU from the regular values during St. Patrick´s Day. Ionosphere-free combination in applied positioning techniques successfully eliminated most of the ionospheric terms. The highest deviations in Up component (to 7 cm) were observed during sudden snowfall characterised by changes in temperature, atmospheric pressure and humidity in the troposphere. Numéro de notice : A2019-167 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.15292/geodetski-vestnik.2019.01.73-91 Date de publication en ligne : 17/01/2019 En ligne : http://dx.doi.org/10.15292/geodetski-vestnik.2019.01.73-91 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92576
in Geodetski vestnik > vol 63 n° 1 (March - May 2019) . - pp 73 - 91[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 139-2019011 RAB Revue Centre de documentation En réserve L003 Disponible Integrating dendrochronology and geomatics to monitor natural hazards and landscape changes / Marco Ciolli in Applied geomatics, vol 11 n° 1 (March 2019)
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Titre : Integrating dendrochronology and geomatics to monitor natural hazards and landscape changes Type de document : Article/Communication Auteurs : Marco Ciolli, Auteur ; Marco Bezzi, Auteur ; Giovanni Comunello, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 39 - 52 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] Albanie
[Termes IGN] analyse diachronique
[Termes IGN] avalanche
[Termes IGN] couvert forestier
[Termes IGN] dendrochronologie
[Termes IGN] forêt
[Termes IGN] GRASS
[Termes IGN] IDRISI
[Termes IGN] lit majeur
[Termes IGN] Pinus sylvestris
[Termes IGN] positionnement par GPS
[Termes IGN] QGIS
[Termes IGN] reboisement
[Termes IGN] risque naturel
[Termes IGN] TrenteRésumé : (Auteur) The monitoring of natural hazards is of extreme importance in the areas of Italy where there are high hydrogeological and avalanche risks. Despite the fact that records of past events are sometimes available, some of their data are often incomplete and show that the monitoring and mapping of these phenomena are never enough to avoid damage. We present the results of different studies where an integrated approach has been used by combining geomatics and dendrochronology techniques. In particular, we refer to case studies concerning avalanches, debris flows, natural reforestation in Italy and riverbed path changes in Albania. The position of all the plants sampled for dendrochronology was taken by GPS (Global Positioning System). The cartographic information used in these studies was provided by official sources from public organisations or processed by extracting them from aerial photographs or satellite imagery. With the Geographic Information System, it was possible to spatialise and analyse the information from dendrochronological sampling through the creation of multi-temporal morphological and potential risk maps showing the effects of the phenomena on forest cover. The GIS software used in these studies are GRASS, QGIS and IDRISI. The results showed that avalanches, debris flow, riverbed and landscape change can be studied effectively by integrating geomatics and dendrochronological techniques. This integration enabled spatial and temporal modelling, including the reconstruction of paths and volumes of past phenomena. The analysis of growth disturbances over time also enabled the reconstruction of the frequency of avalanches and debris flow activity over the last 50 years and, in some areas, over the last century. A detailed analysis of one of the avalanche tracks provided interesting results regarding the reconstruction of avalanche dynamics. Analysis of scars on buried stems of Pinus sylvestris also provided interesting results in terms of debris volume estimation. The dendrochronological reconstruction of the patterns of natural reforestation led to the determination of forest expansion rates that were used for modelling future scenarios and refining the changes of river morphology. Dendrochronology strongly improved the results of GIS satellite imagery analysis. These reconstructions are particularly important for the areas that are more exposed to the direct risk of avalanches, debris flows and floods in order to prevent the consequences of such phenomena in a changing climate. Numéro de notice : A2019-160 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s12518-018-0236-0 Date de publication en ligne : 21/08/2018 En ligne : https://doi.org/10.1007/s12518-018-0236-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92521
in Applied geomatics > vol 11 n° 1 (March 2019) . - pp 39 - 52[article]Performance analysis of dual-frequency receiver using combinations of GPS L1, L5, and L2 civil signals / Padma Bolla in Journal of geodesy, vol 93 n° 3 (March 2019)
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Titre : Performance analysis of dual-frequency receiver using combinations of GPS L1, L5, and L2 civil signals Type de document : Article/Communication Auteurs : Padma Bolla, Auteur ; Kai Borre, Auteur Année de publication : 2019 Article en page(s) : pp 437 - 447 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] bande L
[Termes IGN] mesurage de pseudo-distance
[Termes IGN] précision du positionnement
[Termes IGN] récepteur bifréquence
[Termes IGN] signal GPS
[Termes IGN] test de performance
[Termes IGN] trajet multiple
[Vedettes matières IGN] Traitement de données GNSSRésumé : (Auteur) Processing of GNSS signals from more than one frequency band enhances the accuracy and integrity of a position solution in both standalone and differential positioning. The modern GPS program and newly launched GNSS systems such as GALILEO, BeiDou allow civilians to access signals from multiple frequencies in the L-band spectrum. While there are some advantages in triple-frequency processing in carrier phase applications, in general most of the standalone kinematic receivers get benefit from dual-frequency signals for ionosphere error correction. In implementing a dual-frequency receiver, it is necessary to select a combination of frequencies leading to an optimum performance of the existing civilian signals. In the current research work, we have analyzed the performance of dual-frequency receiver in terms of combined signal observation noise, sensitivity and robustness using analytical models by taking the combination of GPS L1, L2C and L5 signals as an example. Further, we have investigated the benefits of common Doppler estimate-based two-frequency signal tracking to reduce the noise in linear combination of observations. Through analytical and experimental results, it is confirmed that the L1/L5 signal combination in GPS system has low observation noise, which is suitable to use in high accuracy and precise positioning applications using standalone dual-frequency receiver. Further, it is shown that common Doppler estimate-based dual-frequency signal tracking has improved receiver tracking loop performance in terms of observation noise and multipath in linear combination of observations and enhanced receiver sensitivity and robustness. In GPS system, L1/L5 signals processed using common Doppler estimate-aided two-frequency signal tracking architecture, it is possible to effectively mitigate ionosphere delay and other receiver observation errors, to achieve less than 1 m position accuracy using unambiguous code phase observations. Proposed analysis is applicable of finding an optimal two-frequency signal combination in multi-frequency GNSS system and suitable signal processing architecture to obtain high accuracy and precise ionosphere-free position solution using code phase observations in standalone dual-frequency receiver. Numéro de notice : A2019-153 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-018-1172-9 Date de publication en ligne : 14/07/2018 En ligne : https://doi.org/10.1007/s00190-018-1172-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92493
in Journal of geodesy > vol 93 n° 3 (March 2019) . - pp 437 - 447[article]Influence of subdaily model for polar motion on the estimated GPS satellite orbits / Natalia Panafidina in Journal of geodesy, vol 93 n° 2 (February 2019)PermalinkAccounting for the differential inter-system bias (DISB) of code observation in GPS+BDS positioning / Xiang Cao in Journal of applied geodesy, vol 13 n° 1 (January 2019)PermalinkPermalinkEnhancing real-time precise point positioning time and frequency transfer with receiver clock modeling / Yulong Ge in GPS solutions, vol 23 n° 1 (January 2019)PermalinkEstimating and assessing Galileo satellite fractional cycle bias for PPP ambiguity resolution / Guorui Xiao in GPS solutions, vol 23 n° 1 (January 2019)PermalinkImproving multi-GNSS ultra-rapid orbit determination for real-time precise point positioning / Xingxing Li in Journal of geodesy, vol 93 n° 1 (January 2019)PermalinkPermalinkOn constrained integrated total Kalman filter for integrated direct geo-referencing / Vahid Mahboub in Survey review, vol 51 n° 364 (January 2019)PermalinkOptimisation of GNSS networks, considering baseline correlations / M. Amin Alizadeh-Khameneh in Survey review, vol 51 n° 364 (January 2019)PermalinkReal-time capturing of seismic waveforms using high-rate BDS, GPS and GLONASS observations: the 2017 Mw 6.5 Jiuzhaigou earthquake in China / Xingxing Li in GPS solutions, vol 23 n° 1 (January 2019)Permalink