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Galileo and QZSS precise orbit and clock determination using new satellite metadata / Xingxing Li in Journal of geodesy, vol 93 n° 8 (August 2019)
[article]
Titre : Galileo and QZSS precise orbit and clock determination using new satellite metadata Type de document : Article/Communication Auteurs : Xingxing Li, Auteur ; Yongqiang Yuan, Auteur ; Jiande Huang, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 1123 - 1136 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] centre de phase
[Termes IGN] constellation Galileo
[Termes IGN] données satellitaires
[Termes IGN] GIOVE (satellite)
[Termes IGN] horloge du satellite
[Termes IGN] lacet
[Termes IGN] métadonnées
[Termes IGN] modèle d'orbite
[Termes IGN] orbite précise
[Termes IGN] orbitographie
[Termes IGN] Quasi-Zenith Satellite System
[Termes IGN] rayonnement solaire
[Termes IGN] variance d'AllanRésumé : (auteur) During 2016–2018, satellite metadata/information including antenna parameters, attitude laws and physical characteristics such as mass, dimensions and optical properties were released for Galileo and QZSS (except for the QZS-1 optical coefficients). These metadata are critical for improving the accuracy of precise orbit and clock determination. In this contribution, we evaluate the benefits of these new metadata to orbit and clock in three aspects: the phase center offsets and variations (PCO and PCV), the yaw-attitude model and solar radiation pressure (SRP) model. The updating of Galileo PCO and PCV corrections, from the values estimated by Deutsches Zentrum für Luft- und Raumfahrt and Deutsches GeoForschungsZentrum to the chamber calibrations disclosed by new metadata, has only a slight influence on Galileo orbits, with overlap differences within only 1 mm. By modeling the yaw attitude of Galileo satellites and QZS-2 spacecraft (SVN J002) according to new published attitude laws, the residuals of ionosphere-free carrier-phase combinations can be obviously decreased in yaw maneuver seasons. With the new attitude models, the 3D overlap RMS in eclipse seasons can be decreased from 12.3 cm, 14.7 cm, 16.8 cm and 34.7 cm to 11.7 cm, 13.4 cm, 15.8 cm and 32.9 cm for Galileo In-Orbit Validation (IOV), Full Operational Capability (FOC), FOC in elliptical orbits (FOCe) and QZS-2 satellites, respectively. By applying the a priori box-wing SRP model with new satellite dimensions and optical coefficients, the 3D overlap RMS are 5.3 cm, 6.2 cm, 5.3 cm and 16.6 cm for Galileo IOV, FOCe, FOC and QZS-2 satellites, with improvements of 11.0%, 14.7%, 14.0% and 13.8% when compared with the updated Extended CODE Orbit Model (ECOM2). The satellite laser ranging (SLR) validation reveals that the a priori box-wing model has smaller mean biases of − 0.4 cm, − 0.4 cm and 0.6 cm for Galileo FOCe, FOC and QZS-2 satellites, while a slightly larger mean bias of − 1.0 cm is observed for Galileo IOV satellites. Moreover, the SLR residual dependencies of Galileo IOV and FOC satellites on the elongation angle almost vanish when the a priori box-wing SRP model is applied. As for satellite clocks, a visible bump appears in the Modified Allan deviation at integration time of 20,000 s for Galileo Passive Hydrogen Maser with ECOM2, while it almost vanishes when the a priori box-wing SRP model and new metadata are applied. The standard deviations of clock overlap can also be significantly reduced by using new metadata. Numéro de notice : A2019-383 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-019-01230-4 Date de publication en ligne : 02/02/2019 En ligne : https://doi.org/10.1007/s00190-019-01230-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93462
in Journal of geodesy > vol 93 n° 8 (August 2019) . - pp 1123 - 1136[article]Processing of GNSS constellations and ground station networks using the raw observation approach / Sebastian Strasser in Journal of geodesy, vol 93 n°7 (July 2019)
[article]
Titre : Processing of GNSS constellations and ground station networks using the raw observation approach Type de document : Article/Communication Auteurs : Sebastian Strasser, Auteur ; Torsten Mayer-Gürr, Auteur ; Norbert Zehentner, Auteur Année de publication : 2019 Article en page(s) : pp 1045 - 1057 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] analyse diachronique
[Termes IGN] antenne GNSS
[Termes IGN] constellation GNSS
[Termes IGN] données GPS
[Termes IGN] erreur systématique
[Termes IGN] étalonnage d'instrument
[Termes IGN] Global Orbitography Navigation Satellite System
[Termes IGN] horloge du satellite
[Termes IGN] orbitographie
[Termes IGN] position
[Termes IGN] repère de référence
[Termes IGN] retard ionosphèrique
[Termes IGN] station GNSS
[Termes IGN] station GPSRésumé : (auteur) This article describes the raw observation approach as implemented at Graz University of Technology to determine GNSS products like satellite orbits, clocks, and station positions. To assess the performance of the approach, 15 years (2003–2017) of observations from a network of 245 globally distributed IGS stations to the GPS constellation were processed on a daily basis using the IGS14 reference frame and antenna calibrations. The resulting products are evaluated against those determined by IGS analysis centers. Orbit fit quality relative to the IGS combination is comparable to the best-fitting solutions used for evaluation. Starting from early 2017, when the IGS switched to IGS14, the determined orbits fit better to the IGS combination than any other considered solution. Midnight discontinuities show good internal orbit consistency and no noticeable satellite block-dependency. Satellite clocks are comparable to the considered IGS analysis center solutions. Station positions differ from the IGS combination on a similar level to the solutions they were evaluated against. The temporal repeatability of station positions is slightly better than that of the IGS combination. The quality of resulting GNSS products confirms that the raw observation approach is well suited for the task of determining satellite orbits, clocks, and station positions. It provides an alternative to well-established approaches used by IGS analysis centers and simplifies the introduction of additional observables from new and modernized GNSS. Numéro de notice : A2019-358 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-018-1223-2 Date de publication en ligne : 13/12/2018 En ligne : https://doi.org/10.1007/s00190-018-1223-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93426
in Journal of geodesy > vol 93 n°7 (July 2019) . - pp 1045 - 1057[article]Impact of GPS antenna phase center models on zenith wet delay and tropospheric gradients / Yohannes Getachew Ejigu in GPS solutions, vol 23 n° 1 (January 2019)
[article]
Titre : Impact of GPS antenna phase center models on zenith wet delay and tropospheric gradients Type de document : Article/Communication Auteurs : Yohannes Getachew Ejigu, Auteur ; Addisu Hunegnaw, Auteur ; Kibrom Ebuy Abraha, Auteur ; et al., Auteur Année de publication : 2019 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] antenne GPS
[Termes IGN] centre de phase
[Termes IGN] données GPS
[Termes IGN] gradient de troposphère
[Termes IGN] retard troposphérique zénithal
[Termes IGN] teneur intégrée en vapeur d'eau
[Vedettes matières IGN] Traitement de données GNSSRésumé : (Auteur) Today Global Navigation Satellite Systems (GNSS) tropospheric products, such as zenith total delays (ZTD) and zenith wet delays (ZWD), are widely used as complementary data sets in numerical weather prediction models. In particular, the wet delays are treated as unknown parameters in GNSS processing and are estimated with other parameters such as station coordinates. In this study, we investigate the effects of Phase Center Correction (PCC) models on ZWD, integrated water vapor (IWV) and horizontal gradients derived from Global Positioning System (GPS) observations. Two solutions were generated using the GAMIT software over the European Reference Frame (EUREF) Permanent GNSS Network (EPN). The first (reference) solution was derived by applying the International GNSS Service (IGS) type-mean PCC models, while for the second solution PCC models from individual calibrations were used. The solutions were generated identically, except for the PCC model differences. The tropospheric products from the two solutions were then compared, with the assumption that common signals would be differenced out. The comparison of the two solutions clearly shows a bias in all tropospheric products, which can be attributed to PCC model deficiencies. Overall, mean biases of 1.8, 0.3, 0.14 and 0.19 mm are evident in ZWD, IWV, North–South and East–West gradients, respectively. Moreover, the differences between the two solutions show seasonal variations. For all antenna types, the ZWD and IWV differences are dominated by white plus power-law noise, with the latter characterizing the low-frequency spectrum. On the other hand, the horizontal gradients exhibit a white plus first-order autoregressive noise characteristic with less than 1% white noise. The individual PCC model provides a better fit to an external independent model in terms of gradient estimates and also provides up to 3% more carrier phase integer ambiguity resolution. Numéro de notice : A2019-056 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-018-0796-9 Date de publication en ligne : 25/10/2018 En ligne : https://doi.org/10.1007/s10291-018-0796-9 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92085
in GPS solutions > vol 23 n° 1 (January 2019)[article]Validating and comparing GNSS antenna calibrations / Ulla Kallio in Journal of geodesy, vol 93 n° 1 (January 2019)
[article]
Titre : Validating and comparing GNSS antenna calibrations Type de document : Article/Communication Auteurs : Ulla Kallio, Auteur ; Hannu Koivula, Auteur ; Sonja Lahtinen, Auteur ; Ville Nikkonen, Auteur ; Markku Poutanen, Auteur Année de publication : 2019 Article en page(s) : pp 1 - 18 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] antenne GNSS
[Termes IGN] centre de phase
[Termes IGN] erreur systématique
[Termes IGN] étalonnage d'instrument
[Termes IGN] matrice de covariance
[Termes IGN] Metsähovi
[Termes IGN] modèle mathématique
[Termes IGN] positionnement cinématique
[Termes IGN] précision millimétrique
[Termes IGN] résidu
[Termes IGN] test de performanceRésumé : (auteur) GNSS antennas have no fixed electrical reference point. The variation of the phase centre is modelled and tabulated in antenna calibration tables, which include the offset vector (PCO) and phase centre variation (PCV) for each frequency according to the elevations and azimuths of the incoming signal. Used together, PCV and PCO reduce the phase observations to the antenna reference point. The remaining biases, called the residual offsets, can be revealed by circulating and rotating the antennas on pillars. The residual offsets are estimated as additional parameters when combining the daily GNSS network solutions with full covariance matrix. We present a procedure for validating the antenna calibration tables. The dedicated test field, called Revolver, was constructed at Metsähovi. We used the procedure to validate the calibration tables of 17 antennas. Tables from the IGS and three different calibration institutions were used. The tests show that we were able to separate the residual offsets at the millimetre level. We also investigated the influence of the calibration tables from the different institutions on site coordinates by performing kinematic double-difference baseline processing of the data from one site with different antenna tables. We found small but significant differences between the tables. Numéro de notice : A2019-031 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-018-1134-2 Date de publication en ligne : 22/03/2019 En ligne : https://doi.org/10.1007/s00190-018-1134-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91968
in Journal of geodesy > vol 93 n° 1 (January 2019) . - pp 1 - 18[article]Estimation of antenna phase center offset for BDS IGSO and MEO satellites / Guanwen Huang in GPS solutions, vol 22 n° 2 (April 2018)
[article]
Titre : Estimation of antenna phase center offset for BDS IGSO and MEO satellites Type de document : Article/Communication Auteurs : Guanwen Huang, Auteur ; Xingyuan Yan, Auteur ; Zhang Qian, Auteur ; et al., Auteur Année de publication : 2018 Article en page(s) : pp 22 - 49 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Techniques orbitales
[Termes IGN] centre de phase
[Termes IGN] constellation BeiDou
[Termes IGN] orbite géostationnaire
[Termes IGN] orbitographieRésumé : (Auteur) The BeiDou satellite navigation system (BDS) is different from other global navigation satellite systems (GNSSs) because of its special constellation, which consists of satellites in geostationary earth orbit, inclined geosynchronous earth orbit (IGSO), and medium earth orbit (MEO). Compared to MEO satellites, the observations of IGSO satellites cover only a small range of nadir angles. Therefore, the estimation of phase center offsets (PCOs) suffers from high correlation with other estimation parameters. We have estimated the phase center offsets for BeiDou IGSO and MEO satellites with a direct PCO parameters model, and constraints are applied to cope with the correlation between the PCOs and other parameters. Validation shows that the estimated PCO parameters could be used to improve the accuracy of orbit and clock offset overlaps. Compared with the Multi-GNSS Experiment antenna phase center correction model, the average improvements of the proposed method for along-track, cross-track, and radial components are 19 mm (31%), 5 mm (14%), and 2 mm (15%) for MEO satellites, and 13 mm (17%), 12 mm (21%), and 5 mm (19%) for IGSO satellites. For clock offset overlaps, average improvements of standard deviation and root mean square (RMS) are 0.03 ns (20%) and 0.03 ns (12%), respectively. The RMS of precise coordinates in the BDS-only positioning was also improved significantly with a level of 24 mm (30%) in the up-direction. Finally, the overall uncertainty of the estimated results is discussed. Numéro de notice : A2018-159 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-018-0716-z Date de publication en ligne : 24/02/2018 En ligne : https://doi.org/10.1007/s10291-018-0716-z Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89781
in GPS solutions > vol 22 n° 2 (April 2018) . - pp 22 - 49[article]Periodic signals in a pseudo-kinematic GPS coordinate time series depending on the antenna phase centre model – TRM55971.00 TZGD antenna case study / Karol Dawidowicz in Survey review, vol 49 n° 355 (October 2017)PermalinkMultipath detection based on single orthogonal dual linear polarized GNSS antenna / Ke Zhang in GPS solutions, vol 21 n° 3 (July 2017)PermalinkGNSS antenna caused near-field interference effect in Precise Point Positioning results / Karol Dawidowicz in Artificial satellites, vol 52 n° 2 (June 2017)PermalinkGPS code phase variations (CPV) for GNSS receiver antennas and their effect on geodetic parameters and ambiguity resolution / Tobias Kersten in Journal of geodesy, vol 91 n° 6 (June 2017)PermalinkMultivariate analysis of GPS position time series of JPL second reprocessing campaign / Ali Reza Amiri-Simkooei in Journal of geodesy, vol 91 n° 6 (June 2017)PermalinkFast ambiguity resolution for long-range reference station networks with ionospheric model constraint method / Ming Zhang in GPS solutions, vol 21 n° 2 (April 2017)PermalinkSpringer handbook of Global Navigation Satellite Systems / Peter J.G. Teunissen (2017)PermalinkDORIS Starec ground antenna characterization and impact on positioning / Cédric Tourain in Advances in space research, vol 58 n° 12 (15 December 2016)PermalinkBundle adjustment of spherical images acquired with a portable panoramic image mapping system (PPIMS) / Yi-Hsing Tseng in Photogrammetric Engineering & Remote Sensing, PERS, vol 82 n° 12 (December 2016)PermalinkA remark on the GNSS single difference model with common clock scheme for attitude determination / Wantong Chen in Journal of applied geodesy, vol 10 n° 3 (September 2016)Permalink