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Ajouter le résultat dans votre panierPrecision comparison and analysis of four online free PPP services in static positioning and tropospheric delay estimation / Qiuying Guo in GPS solutions, vol 19 n° 4 (october 2015)
Titre : Precision comparison and analysis of four online free PPP services in static positioning and tropospheric delay estimation Type de document : Article/Communication Auteurs : Qiuying Guo, Auteur Année de publication : 2015 Article en page(s) : pp 537 - 544 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] analyse comparative
[Termes IGN] logiciel libre
[Termes IGN] positionnement ponctuel précis
[Termes IGN] positionnement statique
[Termes IGN] précision des données
[Termes IGN] retard troposphériqueRésumé : (auteur) Observation data sets from three different periods and 23 International GNSS Service (IGS) stations spread over the world were processed in static mode using four online free precise point positioning (PPP) services: Automatic Precise Positioning Service (APPS), GPS Analysis and Positioning Software, Canadian Spatial Reference System precise point positioning service, and Magic-PPP. The estimated positions of the 23 IGS stations were compared with the published values. The estimated zenith tropospheric delays (ZTDs) at these stations were compared with the corresponding IGS troposphere products published on the IGS Web site. Furthermore, in order to analyze PPP precision for short observation periods, GPS observation data sets with a sampling rate of 1 s collected by one CORS station were also processed by the four online PPP services. Calculation shows that the precision of daily solutions for north and east (N/E) components estimated by the four online PPP services can reach millimeter level, the precision of ellipsoid elevation (H) can reach 1–2 cm, and precision of ZTDs estimation results is approximately 1–2 cm. Compared with the corresponding values published on the IGS Web site, the precision of ZTDs estimated by APPS is higher than those estimated by the other three PPP online services; the differences between ZTDs by APPS and IGS values are mostly within ±1 cm. For PPP with short observation periods, the precision of N/E components within 2, 1, and 0.5 h observation periods can reach about 2–3, 2–7, and 3–8 cm, respectively, while the precision of H components is about 3–5, 5–12, and 10–18 cm, respectively. Numéro de notice : A2015-464 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-014-0413-5 Date de publication en ligne : 11/10/2014 En ligne : https://doi.org/10.1007/s10291-014-0413-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77147
in GPS solutions > vol 19 n° 4 (october 2015) . - pp 537 - 544[article]
Titre : Instantaneous ambiguity resolution for URTK and its seamless transition with PPP-AR Type de document : Article/Communication Auteurs : Xuan Zou, Auteur ; Weiming Tang, Auteur ; Chuang Shi, Auteur ; Jingnan Liu, Auteur Année de publication : 2015 Article en page(s) : pp 559 - 567 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résolution d'ambiguïté
[Termes IGN] système d'extension
[Termes IGN] véhicule automobileRésumé : (auteur) We extend the current Undifferenced network RTK (URTK) approaches by additionally using P1/CA augmentation information from reference stations. P1/CA augmentation information can shorten the convergence time and help to fix the ionosphere-free combination ambiguities in several epochs. Instantaneous and centimeter-level positioning solutions can be achieved for rovers within the coverage of regional reference network. Also, we develop an approach for seamless transition between URTK and precise point positioning with ambiguity resolution (PPP-AR) and present a new scheme to provide URTK service. Therefore, a service for a large number of rovers can be easily realized in real-time data communication for ambiguity fixing. In addition, the period when augmentation information from a particular reference station is not available can be bridged with the help of PPP-AR. Rovers can experience more operational time with fewer interruptions, which are difficult tasks for current URTK and Network Real-Time Kinematic services. More importantly, with this new scheme, URTK and PPP-AR services can be integrated into a unique PPP-AR system. The obtained convergence time only depends on whether or not the rover is receiving the regional augmentation information. Numéro de notice : A2015-465 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-014-0411-7 Date de publication en ligne : 14/10/2014 En ligne : https://doi.org/10.1007/s10291-014-0411-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77152
in GPS solutions > vol 19 n° 4 (october 2015) . - pp 559 - 567[article]
Titre : Global optimization of GNSS station reference networks Type de document : Article/Communication Auteurs : David Coulot Année de publication : 2015 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] algorithme génétique
[Termes IGN] International GNSS Service
[Termes IGN] optimisation (mathématiques)
[Termes IGN] réseau géodésique permanentRésumé : (auteur) The IGS08 reference network, adopted by the International GNSS Service (IGS) in 2011, and IGS08 core network are both of primary importance for the international GNSS community. They were empirically designed so as to fulfill several standards, such as the quality of the ITRF2008 positions and velocities of the involved stations, the reliability of the data they provide, and their global distribution. The present study shows that such global reference networks and well-distributed sub-networks can be objectively and rigorously designed with genetic algorithms (global optimization stochastic algorithms), on the basis of equivalent criteria. The IGS08-like reference networks and IGS08 core-like sub-networks provided by genetic algorithms respectively outperform the IGS08 and IGS08 core networks for the specific criteria in play. This opens the way to future essential applications: objective design of the next IGS reference and core networks, construction of dynamic core networks, and computation of user-specific global or regional GNSS reference networks. Numéro de notice : A2015-466 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-014-0416-2 Date de publication en ligne : 14/10/2014 En ligne : https://doi.org/10.1007/s10291-014-0416-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77154
in GPS solutions > vol 19 n° 4 (october 2015)[article]
Titre : Tightly coupled integration of GPS precise point positioning and MEMS-based inertial systems Type de document : Article/Communication Auteurs : Mahmoud Abd Rabbou, Auteur ; Ahmed El-Rabbany, Auteur Année de publication : 2015 Article en page(s) : pp 601 - 609 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] centrale inertielle
[Termes IGN] filtre de Kalman
[Termes IGN] GPS-INS
[Termes IGN] implémentation (informatique)
[Termes IGN] Matlab
[Termes IGN] microsystème électromécanique
[Termes IGN] positionnement par GPS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] simple différenceRésumé : (auteur) We develop a new integrated navigation system, which integrates GPS precise point positioning (PPP) with low-cost micro-electro-mechanical sensors (MEMS) inertial system, for precise positioning applications. Currently, most common GPS PPP techniques employ undifferenced ionosphere-free (IF) linear combination. In this work, both undifferenced and between-satellite single-difference (BSSD) IF linear combinations of pseudorange and carrier measurements are considered. IGS precise orbital and clock products are used to correct for satellite orbit and clock errors. Rigorous models are used to account for tropospheric delay, ocean loading, earth tide, carrier phase windup, relativity and satellite antenna phase-center variations. To integrate GPS PPP and MEMS-based inertial systems, the process and measurement models are developed. Tightly coupled mechanization is adopted, which is carried out in the raw measurements domain. Extended Kalman filter is developed to merge the corrected GPS satellite difference observations and inertial measurements and estimate inertial measurements biases and errors. A atlab-based computer program is developed to carry out the tightly coupled integration. The performance of the proposed integrated system is analyzed using a real test situation. It is shown that decimeter-level positioning accuracy is achievable with both undifferenced and BSSD integrated systems. However, in general, better positioning accuracy is obtained with BSSD integrated system. Numéro de notice : A2015-467 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-014-0415-3 Date de publication en ligne : 29/10/2014 En ligne : https://doi.org/10.1007/s10291-014-0415-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77155
in GPS solutions > vol 19 n° 4 (october 2015) . - pp 601 - 609[article]
