Descripteur
Documents disponibles dans cette catégorie (1848)


Etendre la recherche sur niveau(x) vers le bas
An extended inter-system biases model for multi-GNSS precise point positioning / Xuexi Liu in Measurement, vol 206 (January 2023)
![]()
[article]
Titre : An extended inter-system biases model for multi-GNSS precise point positioning Type de document : Article/Communication Auteurs : Xuexi Liu, Auteur ; Weiping Jiang, Auteur ; Pan Li, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 112306 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] distorsion du signal
[Termes IGN] échelle de temps
[Termes IGN] erreur systématique inter-systèmes
[Termes IGN] modèle mathématique
[Termes IGN] positionnement par BeiDou
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] précision du positionnementRésumé : (auteur) The inter-system bias (ISB) is an important parameter in multi-GNSS precise point positioning (PPP). However, on the one hand, the generation mechanism and error components of ISB are not clear. On the other hand, it is unclear whether the ISB parameter should be added to the BDS-2/BDS-3 combined PPP. First, in order to solve these problems, an extended ISB mathematical model is proposed, which unifies the common errors between receiver and satellite, and extends the original ISB model. Second, to demonstrate the correctness of the new model, the components of the new ISB model are verified, and then it is used to explain whether the ISB parameter should be added to BDS-2/BDS-3 combined PPP. Furthermore, 41 stations from the MGEX network and precise products from COD (Center for Orbit Determination in Europe), GBM (Deutsches GeoForschungsZentrum) and WUM (Wuhan University) are used to calculate and analyze the multi-GNSS PPP and ISB during day of year (DOY) 307–365, 2020. Finally, we propose to use a different estimation method of ISB with different precise products to improve the positioning accuracy and shorten the convergence time. The experimental results show that: (1) ISB parameter is composed of five parts: time system error, receiver hardware delay, signal distortion biases (SDB), MGEX-realized (multi-GNSS experiment) time scale and other unmodeled deviations. (2) Due to different receiver hardware delay, SDB and MGEX-realized time scale between BDS-2 and BDS-3, it is necessary to add an ISB parameter in BDS-2/BDS-3 PPP. (3) In multi-GNSS PPP, if the ISB changes greatly but the traditional constant method is used to estimate the ISB parameter, the impact on single station PPP coordinates can reach decimeters. The statistical results demonstrate that the RMS of GBM(CON(Constant)) in East (E), North (N) and Up (U) directions are 2.34 cm, 0.60 cm, and 1.59 cm, respectively, while the RMS of GBM(RWK(Random walk)) decreased by 59.8 %, 13.3 %, and 18.2 %, respectively. Numéro de notice : A2023-028 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1016/j.measurement.2022.112306 Date de publication en ligne : 06/12/2022 En ligne : https://doi.org/10.1016/j.measurement.2022.112306 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102269
in Measurement > vol 206 (January 2023) . - n° 112306[article]Autonomous coordinate establishment of local reference frames for ground-based positioning systems without known points / Tengfei Wang in Journal of geodesy, vol 97 n° 1 (January 2023)
![]()
[article]
Titre : Autonomous coordinate establishment of local reference frames for ground-based positioning systems without known points Type de document : Article/Communication Auteurs : Tengfei Wang, Auteur ; Zheng Yao, Auteur ; Mingquan Lu, Auteur Année de publication : 2023 Article en page(s) : n° 4 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] ambiguïté entière
[Termes IGN] auto-étalonnage
[Termes IGN] mesurage de phase
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement par GNSS
[Termes IGN] pseudolite
[Termes IGN] récepteur
[Termes IGN] signal GPSRésumé : (auteur) Ground-based positioning systems (GBPSs) can serve as a supplement and backup to global navigation satellite systems. GBPSs are known for their low cost and high flexibility, but most of them have difficulty in achieving rapid deployment and operation, since the coordinates of transmitters rely on external precise measurements. Several existing self-calibration methods based on carrier phase measurements require known points of GBPS transmitters or receivers, which implies dependence on external measurements. This paper proposes an autonomous coordinate establishment (ACE) method without using known reference points for GBPSs. ACE utilizes a kinematic receiver to collect carrier phase measurements and employs a three-step procedure to establish a regional coordinate system. In the first step, ACE uses the properties of matrix structures to decouple generalized ambiguities and coordinates. Then, ACE obtains the rough estimation of the transmitter coordinates via multi-dimensional scaling in the second step. In the third step, ACE refines the estimate by solving a least squares problem which would be difficult to solve without the previous two steps. Numerical simulations and a real-world experiment show that the coordinate estimation of ACE can achieve decimeter to centimeter-level accuracy. The proposed method enables rapid deployment and operation for GBPSs. Numéro de notice : A2023-123 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-022-01687-w Date de publication en ligne : 04/01/2023 En ligne : https://doi.org/10.1007/s00190-022-01687-w Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102499
in Journal of geodesy > vol 97 n° 1 (January 2023) . - n° 4[article]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)
![]()
[article]
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]In-camera IMU angular data for orthophoto projection in underwater photogrammetry / Erica Nocerino in ISPRS Open Journal of Photogrammetry and Remote Sensing, vol 7 (January 2023)
![]()
[article]
Titre : In-camera IMU angular data for orthophoto projection in underwater photogrammetry Type de document : Article/Communication Auteurs : Erica Nocerino, Auteur ; Fabio Menna, Auteur Année de publication : 2023 Article en page(s) : n° 100027 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie
[Termes IGN] caméra numérique
[Termes IGN] carte bathymétrique
[Termes IGN] centrale inertielle
[Termes IGN] compensation par faisceaux
[Termes IGN] mesure géodésique
[Termes IGN] orthophotographie
[Termes IGN] photogrammétrie sous-marine
[Termes IGN] positionnement par GNSS
[Termes IGN] redressement différentiel
[Termes IGN] roulis
[Termes IGN] structure-from-motion
[Termes IGN] tangageRésumé : (auteur) Among photogrammetric products, orthophotos are probably the most versatile and widely used in many fields of application. In the last years, coupled with the spread of semi-automated survey and processing approaches based on photogrammetry, orthophotos have become almost a standard for monitoring the underwater environment. If on land the definition of the reference coordinate system and projection plane for the orthophoto generation is trivial, underwater it may represent a challenge. In this paper, we address the issue of defining the vertical direction and resulting horizontal plane (levelling) for the differential ortho rectification. We propose a non-invasive, contactless method based on roll and pitch angular data provided by in-camera IMU sensors and embedded in the Exif metadata of JPEG and raw image files. We show how our approach can be seamlessly integrated into automatic SfM/MVS pipelines, provide the mathematical background, and showcase real-world applications results in an underwater monitoring project. The results illustrate the effectiveness of the proposed method and, for the first time, provide a metric evaluation of the definition of the vertical direction with low-cost sensors enclosed in digital cameras directly underwater. Numéro de notice : A2023-119 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Numéro de périodique DOI : 10.1016/j.ophoto.2022.100027 Date de publication en ligne : 07/12/2022 En ligne : https://doi.org/10.1016/j.ophoto.2022.100027 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102493
in ISPRS Open Journal of Photogrammetry and Remote Sensing > vol 7 (January 2023) . - n° 100027[article]Multipath mitigation for improving GPS narrow-lane uncalibrated phase delay estimation and speeding up PPP ambiguity resolution / Kai Zheng in Measurement, vol 206 (January 2023)
![]()
[article]
Titre : Multipath mitigation for improving GPS narrow-lane uncalibrated phase delay estimation and speeding up PPP ambiguity resolution Type de document : Article/Communication Auteurs : Kai Zheng, Auteur ; Lingmin Tan, Auteur ; Kezhong Liu, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 112243 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] analyse en composantes principales
[Termes IGN] atténuation
[Termes IGN] correction du trajet multiple
[Termes IGN] mesurage de pseudo-distance
[Termes IGN] phase GPS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résolution d'ambiguïté
[Termes IGN] temps de convergence
[Termes IGN] trajet multipleRésumé : (auteur) Precise point positioning (PPP) has been recognized as a powerful tool for various geophysical applications. However, the long convergence time required to resolve a reliable ambiguity impedes its further application in time-critical scenarios. Although PPP ambiguity resolution (AR) can shorten the convergence time, its performance is subject to the quality of float ambiguity estimates and the uncalibrated phase delay (UPD), which can be contaminated by multipath errors. Furthermore, the observation residuals derived from PPP are very likely to be affected by the common-mode error (CME), thereby deteriorating the multipath modeling accuracy. The principal component analysis (PCA) is employed to mitigate the CME effect, and the multipath is modeled using a multipath hemispherical map (MHM). Consequently, the narrow-lane (NL) UPDs with multipath correction have better temporal stability and residual distributions than those without correction. Compared with sidereal filtering (SF), the MHM0.5 has comparable residual variance reduction percentages, indicating its capability of capturing high-frequency multipath. For static PPP AR, the averaged time to first fix (TTFF) can be reduced by 24.2% to about 26 min and the convergence time can be achieved within 16.2 min after multipath correction. The pseudorange multipath correction significantly contributes to shortening the TTFF and convergence time. Reducing the resolution of MHM increases the risk of extending the TTFF. For kinematic PPP AR with MHM0.5, the convergence time exhibits a remarkable improvement when compared with that of the uncorrected case (21.7 min versus 40.2 min), and 20% of the stations achieve convergence within 10 min. Meanwhile, a few stations only take one minute to achieve convergence. The contribution of the multipath correction to the fixing rate is comparatively small. After applying MHM0.5, the kinematic positioning accuracies are improved by 35.7%, 12.6%, and 24.4% to 1.26, 1.39, and 2.73 cm for the east, north, and up components, respectively. Numéro de notice : A2023-027 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1016/j.measurement.2022.112243 Date de publication en ligne : 24/11/2022 En ligne : https://doi.org/10.1016/j.measurement.2022.112243 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102267
in Measurement > vol 206 (January 2023) . - n° 112243[article]A nonlinear Gauss-Helmert model and its robust solution for seafloor control point positioning / Yingcai Kuang in Marine geodesy, vol 46 n° 1 (January 2023)
PermalinkA real-time algorithm for continuous navigation in intelligent transportation systems using LiDAR-Gyroscope-Odometer integration / Tarek Hassan in Journal of applied geodesy, vol 17 n° 1 (January 2023)
PermalinkHigh-precision positioning using plane-constrained RTK method in urban environments / Chen Zhuang in Navigation : journal of the Institute of navigation, vol 69 n° 4 (Fall 2022)
PermalinkA method to determine secondary codes and carrier phases of short snapshot signals / Xiao Liu in Navigation : journal of the Institute of navigation, vol 69 n° 4 (Fall 2022)
PermalinkNavigation and Ionosphere Characterization Using High-Frequency Signals: A Performance Analysis / Yoav Baumgarten in Navigation : journal of the Institute of navigation, vol 69 n° 4 (Fall 2022)
PermalinkPPP-RTK: from common-view to all-in-view GNSS networks / Baocheng Zhang in Journal of geodesy, vol 96 n° 12 (December 2022)
PermalinkSemantic segmentation of bridge components and road infrastructure from mobile LiDAR data / Yi-Chun Lin in ISPRS Open Journal of Photogrammetry and Remote Sensing, vol 6 (December 2022)
PermalinkA fast satellite selection algorithm for multi-GNSS marine positioning based on improved particle swarm optimisation / Xiaoguo Guan in Survey review, vol 54 n° 387 (November 2022)
PermalinkOn the relation of GNSS phase center offsets and the terrestrial reference frame scale: a semi-analytical analysis / Oliver Montenbruck in Journal of geodesy, vol 96 n° 11 (November 2022)
PermalinkPPP–RTK theory for varying transmitter frequencies with satellite and terrestrial positioning applications / Peter J.G. Teunissen in Journal of geodesy, vol 96 n° 11 (November 2022)
Permalink