Descripteur
Documents disponibles dans cette catégorie (1438)


Etendre la recherche sur niveau(x) vers le bas
Integrated processing of ground- and space-based GPS observations: improving GPS satellite orbits observed with sparse ground networks / Wen Huang in Journal of geodesy, vol 94 n° 10 (October 2020)
![]()
[article]
Titre : Integrated processing of ground- and space-based GPS observations: improving GPS satellite orbits observed with sparse ground networks Type de document : Article/Communication Auteurs : Wen Huang, Auteur ; Benjamin Männel, Auteur ; Pierre Sakic-Kieffer, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : 13 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Techniques orbitales
[Termes IGN] modèle d'orbite
[Termes IGN] orbite basse
[Termes IGN] orbite précise
[Termes IGN] orbitographie
[Termes IGN] orbitographie par GNSS
[Termes IGN] récepteur GPS
[Termes IGN] station GPSRésumé : (auteur) The precise orbit determination (POD) of Global Navigation Satellite System (GNSS) satellites and low Earth orbiters (LEOs) are usually performed independently. It is a potential way to improve the GNSS orbits by integrating LEOs onboard observations into the processing, especially for the developing GNSS, e.g., Galileo with a sparse sensor station network and Beidou with a regional distributed operating network. In recent years, few studies combined the processing of ground- and space-based GNSS observations. The integrated POD of GPS satellites and seven LEOs, including GRACE-A/B, OSTM/Jason-2, Jason-3 and, Swarm-A/B/C, is discussed in this study. GPS code and phase observations obtained by onboard GPS receivers of LEOs and ground-based receivers of the International GNSS Service (IGS) tracking network are used together in one least-squares adjustment. The POD solutions of the integrated processing with different subsets of LEOs and ground stations are analyzed in detail. The derived GPS satellite orbits are validated by comparing with the official IGS products and internal comparison based on the differences of overlapping orbits and satellite positions at the day-boundary epoch. The differences between the GPS satellite orbits derived based on a 26-station network and the official IGS products decrease from 37.5 to 23.9 mm (34% improvement) in 1D-mean RMS when adding seven LEOs. Both the number of the space-based observations and the LEO orbit geometry affect the GPS satellite orbits derived in the integrated processing. In this study, the latter one is proved to be more critical. By including three LEOs in three different orbital planes, the GPS satellite orbits improve more than from adding seven well-selected additional stations to the network. Experiments with a ten-station and regional network show an improvement of the GPS satellite orbits from about 25 cm to less than five centimeters in 1D-mean RMS after integrating the seven LEOs. Numéro de notice : A2020-630 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-020-01424-1 Date de publication en ligne : 10/10/2020 En ligne : https://doi.org/10.1007/s00190-020-01424-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96049
in Journal of geodesy > vol 94 n° 10 (October 2020) . - 13 p.[article]GRACE-FO precise orbit determination and gravity recovery / Z. Kang in Journal of geodesy, vol 94 n° 9 (September 2020)
![]()
[article]
Titre : GRACE-FO precise orbit determination and gravity recovery Type de document : Article/Communication Auteurs : Z. Kang, Auteur ; S. Bettadpur, Auteur ; P. Nagel, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : n° 85 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] bande K
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] données GRACE
[Termes IGN] double différence
[Termes IGN] interféromètre au laser
[Termes IGN] orbite précise
[Termes IGN] orbitographieRésumé : (auteur) The gravity recovery and climate experiment follow-on (GRACE-FO) satellites, launched in May of 2018, are equipped with geodetic quality GPS receivers for precise orbit determination (POD) and gravity recovery. The primary objective of the GRACE-FO mission is to map the time-variable and mean gravity field of the Earth. To achieve this goal, both GRACE-FO satellites are additionally equipped with a K-band ranging (KBR) system, accelerometers and star trackers. Data processing strategies, data weighting approaches and impacts of observation types and rates are investigated in order to determine the most efficient approach for processing GRACE-FO multi-type data for precise orbit determination and gravity recovery. Two GPS observation types, un-differenced (UD) and double-differenced (DD) observations in general can be used for GPS-based POD and gravity recovery. The GRACE-FO KBR observations are mainly used for gravity recovery, but they can be also used for POD to improve the relative orbit accuracy. The main purpose of this paper is to study the impacts of the DD, UD and KBR observations on GRACE-FO POD and gravity recovery. The precise orbit accuracy is assessed using several tests, which include analysis of orbital fits, satellite laser ranging residuals, KBR range residuals and orbit comparisons. The gravity recovery is validated by comparing different gravity solutions through coefficient-wise comparison, degree difference variances and water height variations over the whole Earth and selected area and river basins. Numéro de notice : A2020-542 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-020-01414-3 Date de publication en ligne : 16/08/2020 En ligne : https://doi.org/10.1007/s00190-020-01414-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95744
in Journal of geodesy > vol 94 n° 9 (September 2020) . - n° 85[article]A history of laser scanning, Part 1: space and defense applications / Adam P. Spring in Photogrammetric Engineering & Remote Sensing, PERS, vol 86 n° 7 (July 2020)
![]()
[article]
Titre : A history of laser scanning, Part 1: space and defense applications Type de document : Article/Communication Auteurs : Adam P. Spring, Auteur Année de publication : 2020 Article en page(s) : pp 419-429 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] balayage laser
[Termes IGN] capteur à balayage
[Termes IGN] défense nationale
[Termes IGN] histoire des sciences et techniques
[Termes IGN] navigation autonome
[Termes IGN] secteur spatial
[Termes IGN] semis de points
[Termes IGN] véhicule sans piloteRésumé : (Auteur) This article presents the origins and evolution of midrange terrestrial laser scanning (TLS), spanning primarily from the 1950s to the time of publication. Particular attention is given to developments in hardware and software that document the physical dimensions of a scene as a point cloud. These developments include parameters for accuracy, repeatability, and resolution in the midrange—millimeter and centimeter levels when recording objects at building and landscape scales up to a kilometer away. The article is split into two parts: Part one starts with early space and defense applications, and part two examines the survey applications that formed around TLS technologies in the 1990s. The origins of midrange TLS, ironically, begin in space and defense applications, which shaped the development of sensors and information processing via autonomous vehicles. Included are planetary rovers, space shuttles, robots, and land vehicles designed for relative navigation in hostile environments like space and war zones. Key people in the midrange TLS community were consulted throughout the 10-year period over which this article was written. A multilingual and multidisciplinary literature review—comprising media written or produced in Chinese, English, French, German, Japanese, Italian, and Russian—was also an integral part of this research. Numéro de notice : A2020-381 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.14358/PERS.86.7.419 Date de publication en ligne : 01/07/2020 En ligne : https://doi.org/10.14358/PERS.86.7.419 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95426
in Photogrammetric Engineering & Remote Sensing, PERS > vol 86 n° 7 (July 2020) . - pp 419-429[article]Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 105-2020071 SL Revue Centre de documentation Revues en salle Disponible Orbit and clock analysis of BDS-3 satellites using inter-satellite link observations / Xin Xie in Journal of geodesy, vol 94 n° 7 (July 2020)
![]()
[article]
Titre : Orbit and clock analysis of BDS-3 satellites using inter-satellite link observations Type de document : Article/Communication Auteurs : Xin Xie, Auteur ; Tao Geng, Auteur ; Qile Zhao, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : n° 64 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] constellation BeiDou
[Termes IGN] horloge du satellite
[Termes IGN] orbite géostationnaire
[Termes IGN] orbite terrestre
[Termes IGN] orbitographie
[Termes IGN] variance d'AllanRésumé : (auteur) China is currently focusing on the establishment of its BDS-3 system, and a BDS-3 constellation with 18 satellites in medium Earth orbit (MEO) and one satellite in geostationary Earth orbit (GEO) has been able to provide preliminary global services since the end of 2018. These BDS-3 satellites feature the inter-satellite link (ISL) and new high-quality onboard clocks. In this study, we present the analysis of BDS-3 orbits and clocks determined by Ka-band ISL measurements from 18 MEO satellites and one GEO satellite. The ISL data of 43 days from 1 January to 12 February 2019 are used. The BDS-3 ISL measurement is described by a dual one-way ranging model. After converting bidirectional observations to the same epoch, Ka-band clock-free and geometry-free observables are obtained by the addition and subtraction of dual one-way observations, respectively. One anchor station with Ka-band bidirectional observations is introduced into the orbit determination to provide the orientation constraints. Using Ka-band clock-free observables, BDS-3 satellite orbits are determined. The ISL hardware delays are estimated together with orbits, and the resulting hardware delay estimates are quite stable with STD of about 0.03 ns. The Ka-band orbits are evaluated by orbit overlap differences, comparison with L-band precise orbits, and satellite laser ranging validation. The results indicate that the radial orbit errors are on the 2–4 cm level for MEO satellites and 8–10 cm for the GEO satellite. In addition, we investigate the ground anchoring capability by adding one anchor station and reducing the amount of data of the anchor station. Using Ka-band geometry-free observables, BDS-3 satellite clocks are estimated and the RMS of post-fit ISL residuals is about 5 cm. The Ka-band clock offsets are analyzed and compared with L-band precise clocks. Independent of orbit errors, the Allan deviation of Ka-band clocks for averaging interval longer than 5000 s is superior to that of L-band clocks. Furthermore, a pronounced bump, which appears in the Allan deviation of L-band clocks, almost vanishes in Ka-band clocks. Finally, the periodic variations are detected for L-band and Ka-band clocks. Numéro de notice : A2020-534 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-020-01394-4 Date de publication en ligne : 08/07/2020 En ligne : https://doi.org/10.1007/s00190-020-01394-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95724
in Journal of geodesy > vol 94 n° 7 (July 2020) . - n° 64[article]DORIS, 30 ans d'opérations continues au coeur de la performance des missions altimétriques pour l'océanographie et les applications géodésiques / Anonyme in XYZ, n° 163 (juin 2020)
[article]
Titre : DORIS, 30 ans d'opérations continues au coeur de la performance des missions altimétriques pour l'océanographie et les applications géodésiques Type de document : Article/Communication Auteurs : Anonyme, Auteur Année de publication : 2020 Article en page(s) : pp 20 - 20 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] océanographie spatiale
[Termes IGN] Poseidon
[Termes IGN] positionnement par DORIS
[Termes IGN] précision du positionnement
[Termes IGN] réseau Doris
[Termes IGN] SWOT
[Termes IGN] TOPEXRésumé : (Auteur) Le système DORIS (Détermination d'Orbite et Radio positionnement Intégrés par Satellite) a été conçu et développé au début des années 80 par le CNES, l'IGN et le GRGS pour déterminer les positions des satellites avec une grande précision afin de soutenir les missions altimétriques dédiées à la surveillance des océans. Numéro de notice : A2020-387 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtSansCL DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95482
in XYZ > n° 163 (juin 2020) . - pp 20 - 20[article]Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 112-2020021 SL Revue Centre de documentation Revues en salle Disponible Geodetic VLBI for precise orbit determination of Earth satellites: a simulation study / Grzegorz Klopotek in Journal of geodesy, vol 94 n° 6 (June 2020)
PermalinkImproved SMAP dual-channel algorithm for the retrieval of soil moisture / Mario Julian Chaubell in IEEE Transactions on geoscience and remote sensing, vol 58 n° 6 (June 2020)
PermalinkThe geometric imaging model for high-resolution optical remote sensing satellites considering light aberration and atmospheric refraction errors / Mi Wang in Photogrammetric Engineering & Remote Sensing, PERS, vol 86 n° 6 (June 2020)
PermalinkA precise visual localisation method for the Chinese Chang’e‐4 Yutu‐2 rover / YouQing Ma in Photogrammetric record, vol 35 n° 169 (March 2020)
PermalinkSmoothing and predicting celestial pole offsets using a Kalman filter and smoother / Jolanta Nastula in Journal of geodesy, Vol 94 n°3 (March 2020)
PermalinkComparison of atmospheric mass density models using a new data source: COSMIC satellite ephemerides / Yang Yang (2020)
PermalinkEstimation and representation of regional atmospheric corrections for augmenting real-time single-frequency PPP / Peiyuan Zhou in GPS solutions, vol 24 n° 1 (January 2020)
PermalinkPermalinkImpact of thermospheric mass density on the orbit prediction of LEO satellites / Changyong He in Space weather, vol 18 n° 1 (January 2020)
PermalinkPermalink