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BDS and GPS side-lobe observation quality analysis and orbit determination with a GEO satellite onboard receiver / Wenwen Li in GPS solutions, vol 27 n° 1 (January 2023)
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Titre : BDS and GPS side-lobe observation quality analysis and orbit determination with a GEO satellite onboard receiver Type de document : Article/Communication Auteurs : Wenwen Li, Auteur ; Kecai Jiang, Auteur ; Min Li, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 18 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Techniques orbitales
[Termes IGN] code GNSS
[Termes IGN] orbite géostationnaire
[Termes IGN] orbite précise
[Termes IGN] orbitographie
[Termes IGN] orbitographie par GNSS
[Termes IGN] phase
[Termes IGN] positionnement par BeiDou
[Termes IGN] positionnement par GPSRésumé : (auteur) Multi-GNSS combination can alleviate problems associated with GNSS-based geostationary earth orbit (GEO) satellite navigation and orbit determination (OD), such as GNSS availability and observation geometry deterioration. However, only GPS has been widely applied and investigated in GEO missions, whereas GEO OD with BDS requires further exploration. The Chinese GEO satellite TJS-5, equipped with a GPS and BDS-compatible receiver, is the first GEO mission that tracks both BDS 2nd and 3rd generation satellites since BDS global deployment. With the TJS-5 real onboard data, we evaluate BDS side-lobe signal performance and the BDS contribution to GEO OD. Due to transmit antenna gain deficiencies in the side lobes, BDS shows a worse tracking performance than GPS with an average satellite number of 4.3 versus 7.8. Both GPS and BDS reveal inconsistency between carrier-phase and code observations, which reaches several meters and significantly degrades post-dynamic OD calculation. We estimate the consistency as a random walk process in the carrier-phase observation model to reduce its impact. With inconsistency estimated, the post-fit carrier-phase residuals decrease from 0.21 to 0.09 m for both GPS and BDS. The OD precision is significantly improved, from 1.95 to 1.42 m with only GPS and from 3.14 to 2.71 m with only BDS; the GPS and BDS combined OD exhibits the largest improvement from 1.74 to 0.82 m, demonstrating that adding BDS improves the OD precision by 43.3%. The above results indicate that the proposed carrier-phase inconsistency estimation approach is effective for both GPS and BDS and can achieve an orbit precision within 1.0 m using multi-GNSS measurements. Numéro de notice : A2023-026 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-022-01358-5 Date de publication en ligne : 06/11/2022 En ligne : https://doi.org/10.1007/s10291-022-01358-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102261
in GPS solutions > vol 27 n° 1 (January 2023) . - n° 18[article]Precise orbit determination for BDS-3 GEO satellites enhanced by intersatellite links / Xiaojie Li in GPS solutions, vol 27 n° 1 (January 2023)
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Titre : Precise orbit determination for BDS-3 GEO satellites enhanced by intersatellite links Type de document : Article/Communication Auteurs : Xiaojie Li, Auteur ; Xiaogong Hu, Auteur ; Rui Guo, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 8 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Techniques orbitales
[Termes IGN] constellation BeiDou
[Termes IGN] décalage d'horloge
[Termes IGN] orbite géostationnaire
[Termes IGN] orbite précise
[Termes IGN] orbitographie
[Termes IGN] qualité des donnéesRésumé : (auteur) Geostationary orbit (GEO) satellites are an integral part of the BeiDou Navigation Satellite System (BDS). Precise orbit determination (POD) for GEO satellites is difficult due to their geostationary characteristics. The orbit determination accuracy that can be achieved based on regional tracking stations in China cannot satisfy high-precision service requirements. The third generation of BDS (BDS-3) is the first global navigation satellite system that synergistically uses regional monitoring stations and global intersatellite links (ISLs) to realize global service. In this study, the quality of ISL data is analyzed based on the residuals of the intersatellite clock offset and the observed-minus-computed residuals of the ISL data. The orbit determination accuracy is assessed based on the observation residuals, the multiday consistency of the ISL time delays, overlapping orbit comparison, the user equivalent range error (UERE), and the accuracy of the clock offset. The results show that the ISL measurement noise for the GEO satellites is 3 cm, and the multiday consistency accuracy of the ISL time delay is better than 0.07 ns. Compared to the satellite-to-ground link (SGL)-based orbit determination method, the root mean square (RMS) three-dimensional (3D) position error of the overlapping orbit differences (OODs) is improved from 1.11 to 0.22 m with the combined SGL- and ISL-based method. Simultaneously, the UERE improves from 0.57 to 0.19 m, and the accuracy of the satellite clock offset improves from 1.09 to 0.61 ns. Numéro de notice : A2023-001 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-022-01330-3 Date de publication en ligne : 14/10/2022 En ligne : https://doi.org/10.1007/s10291-022-01330-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101870
in GPS solutions > vol 27 n° 1 (January 2023) . - n° 8[article]Precise onboard time synchronization for LEO satellites / Florian Kunzi in Navigation : journal of the Institute of navigation, vol 69 n° 3 (Fall 2022)
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Titre : Precise onboard time synchronization for LEO satellites Type de document : Article/Communication Auteurs : Florian Kunzi, Auteur ; Oliver Montenbruck, Auteur Année de publication : 2022 Article en page(s) : n° 531 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Techniques orbitales
[Termes IGN] données GNSS
[Termes IGN] horloge
[Termes IGN] orbite basse
[Termes IGN] orbitographie
[Termes IGN] oscillateur
[Termes IGN] récepteur DORIS
[Termes IGN] récepteur GNSS
[Termes IGN] récepteur trifréquence
[Termes IGN] synchronisation
[Termes IGN] temps réelRésumé : (auteur) Onboard time synchronization is an important requirement for a wide range of low Earth orbit (LEO) missions such as altimetry or communication services, and extends to future position, navigation, and timing (PNT) services in LEO. For GNSS-based time synchronization, continuous knowledge about the satellite’s position is required and, eventually, the quality of the position solution defines the timing precision attainable through GNSS measurements. Previous research has shown that real-time GNSS orbit determination of LEO satellites can achieve decimeter-level accuracy. This paper characterizes the performance of GNSS-based real-time clock synchronization in LEO using the satellite Sentinel-6A as a real-world case study. The satellite’s ultra-stable oscillator (USO) and triple-frequency GPS/Galileo receiver provide measurements for a navigation filter representative of real-time onboard processing. Continuous evaluation of actual flight data over 14 days shows that a 3D orbit root-mean-square (RMS) error of 11 cm and a 0.9-ns clock standard deviation can be achieved. Numéro de notice : A2022-822 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.33012/navi.531 Date de publication en ligne : 12/04/2022 En ligne : https://doi.org/10.33012/navi.531 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101991
in Navigation : journal of the Institute of navigation > vol 69 n° 3 (Fall 2022) . - n° 531[article]Le cheminement du douzième parallèle (deuxième partie) : article tiré de Jalon, bulletin de l’association des personnels retraités de l’IGN, n° 146-bis de mai 2022 / Jean-Claude Leblanc in XYZ, n° 172 (septembre 2022)
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Titre : Le cheminement du douzième parallèle (deuxième partie) : article tiré de Jalon, bulletin de l’association des personnels retraités de l’IGN, n° 146-bis de mai 2022 Type de document : Article/Communication Auteurs : Jean-Claude Leblanc, Auteur Année de publication : 2022 Article en page(s) : pp 53 - 61 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Nivellement
[Termes IGN] astronomie de position
[Termes IGN] cheminement altimétrique
[Termes IGN] cheminement tellurométrique
[Termes IGN] cheminement topographique
[Termes IGN] frontière naturelle
[Termes IGN] Mali
[Termes IGN] mission de terrain
[Termes IGN] nivellement direct
[Termes IGN] rattachement de station
[Termes IGN] Sénégal
[Termes IGN] Tchad, lacRésumé : (Auteur) Plus courte et plus animée, cette deuxième mission se composait de 14 personnes de l’IGN, de deux Américains et des personnels locaux. Le chef de la mission était Hervé Guichard qui était en séjour au Centre de Brazzaville ; collègue “fabuleux” (c’était son adjectif favori). Nous sommes arrivés à Fort-Lamy (N’Djamena) le 5 janvier 1968. Le travail reprenait au dernier point observé l’année précédente. Il restait environ 200 km pour rejoindre la frontière Cameroun-Nigéria. Le cheminement passe entre le lac Tchad et Fort-Lamy, zone plus boisée que le trajet précédent. Cette deuxième mission était donc plus légère ; nous étions répartis en deux groupes : la reconnaissance-construction et les autres équipes qui partageaient le même campement. Les nuits sans observation étaient assez festives compte tenu du dynamisme d’Hervé, avec sa guitare. La plus mémorable des soirées fut lors d’un bref séjour d’un officiel américain d’origine allemande. Numéro de notice : A2022-674 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Date de publication en ligne : 01/09/2022 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101638
in XYZ > n° 172 (septembre 2022) . - pp 53 - 61[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 112-2022031 SL Revue Centre de documentation Revues en salle Disponible Evaluation of QZSS orbit and clock products for real-time positioning applications / Brian Bramanto in Journal of applied geodesy, vol 16 n° 3 (July 2022)
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Titre : Evaluation of QZSS orbit and clock products for real-time positioning applications Type de document : Article/Communication Auteurs : Brian Bramanto, Auteur ; Irwan Gumilar, Auteur Année de publication : 2022 Article en page(s) : pp 165 - 179 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] décalage d'horloge
[Termes IGN] données GNSS
[Termes IGN] perturbation orbitale
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] qualité du signal
[Termes IGN] Quasi-Zenith Satellite System
[Termes IGN] retard ionosphèriqueRésumé : (auteur) The Quasi-Zenith Satellite System (QZSS) is the recent Japanese satellite positioning system to enhance the positioning accuracy in Japan’s urban areas. Additionally, they provide precise orbit and clock corrections and can be obtained through their experimental signals (LEX), streaming access, and published site. Multi-GNSS Advanced Demonstration tool for Orbit and Clock Analysis (MADOCA) is one of the precise products offered in QZSS services that can be obtained on a global scale. In this study, we evaluated the performance of MADOCA orbit and clock corrections, particularly for real-time positioning applications using LEX signals. Based on the simulation, we predict that 16 countries in the East Asia and Oceania regions will gain the maximum benefit of the LEX signals. However, we stress that one may have difficulties decoding the LEX signals at regions where only one QZSS satellite is observed. During our sailing expedition at Sumatran Sea, we could only decode up to 37 % LEX signals for the observation period. It profoundly increased up to 95 % at Sulawesi Strait where at least three QZSS satellites with an elevation angle of, at its minimum, 40° were observed. The orbit and clock accuracy is estimated to be 5.2 cm and 0.6 ns with respect to International GNSS Service (IGS) final products. Our simulation of using the Real-Time Precise Point Positioning (RTPPP) method revealed that the accuracy of the corresponding positioning applications was less than one decimeter. Further, we compared the MADOCA products for RTPPP applications with Apex5 positioning solutions in static field observations. The positioning accuracy for MADOCA-RTPPP during the field observations was estimated to be centimeter to decimeter level and is slightly worse than Apex5 positioning solutions. Nevertheless, we highlight vast positioning applications using MADOCA-RTPPP, e. g., survey and mapping, smart agriculture, and offshore engineering navigation. Numéro de notice : A2022-494 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/jag-2021-0064 Date de publication en ligne : 03/02/2022 En ligne : https://doi.org/10.1515/jag-2021-0064 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100981
in Journal of applied geodesy > vol 16 n° 3 (July 2022) . - pp 165 - 179[article]A new ambiguity resolution method for LEO precise orbit determination / Xingyu Zhou in Journal of geodesy, vol 96 n° 7 (July 2022)
PermalinkPermalinkAdaptive Kalman filter for real-time precise orbit determination of low earth orbit satellites based on pseudorange and epoch-differenced carrier-phase measurements / Min Li in Remote sensing, vol 14 n° 9 (May-1 2022)
PermalinkCharacteristics of the BDS-3 multipath effect and mitigation methods using precise point positioning / Ran Lu in GPS solutions, vol 26 n° 2 (April 2022)
PermalinkEffect of PCV and attitude on the precise orbit determination of Jason-3 satellite / Kai Li in Journal of applied geodesy, vol 16 n° 2 (April 2022)
PermalinkLEO satellite clock analysis and prediction for positioning applications / Kan Wang in Geo-spatial Information Science, vol 25 n° 1 (March 2022)
PermalinkCalibrating GNSS phase biases with onboard observations of low earth orbit satellites / Xingxing Li in Journal of geodesy, vol 96 n° 2 (February 2022)
PermalinkComparison of atmospheric mass density models using a new data source: COSMIC satellite ephemerides / Yang Yang in IEEE Aerospace and Electronic Systems Magazine, vol 37 n° 2 (February 2022)
PermalinkPermalinkOn-orbit BDS signals and transmit antenna gain analysis for a geostationary satellite / Meng Wang in Advances in space research, vol 69 n° 7 (April 2022)
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