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INS-assisted inter-system biases estimation and inter-system ambiguity resolution in a complex environment / Wenhao Zhao in GPS solutions, vol 27 n° 1 (January 2023)
[article]
Titre : INS-assisted inter-system biases estimation and inter-system ambiguity resolution in a complex environment Type de document : Article/Communication Auteurs : Wenhao Zhao, Auteur ; Genyou Liu, Auteur ; Ming Gao, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 3 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] centrale inertielle
[Termes IGN] erreur systématique inter-systèmes
[Termes IGN] filtre de Kalman
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] résolution d'ambiguïté
[Termes IGN] système complexe
[Termes IGN] trajet multipleRésumé : (auteur) The inter-system real-time kinematic (RTK) model in which multiple systems choose the same reference satellite uses more observations than the traditional intra-system RTK model; however, it is still difficult to accurately determine the differential inter-system biases (DISB) and inter-system ambiguity in a complex environment. We propose a tightly coupled inter-system RTK/INS model that uses the high-precision position information the inertial navigation system (INS) provides to assist in DISB estimation and inter-system ambiguity resolution. Vehicle experiments on urban roads were designed to verify the effectiveness of the method. The vehicle experiments consisted of a simulated rare satellite environment with a high cutoff elevation angle and a real complex environment with buildings and trees obscuration. A robust Kalman filter strategy is used to combat the effects of multipath and non-line-of-sight signals in real complex environments. The results indicate that with the help of INS, the standard deviation of phase and code DISB is reduced by 11 and 17%, respectively, in the simulated environment and by 33 and 18%, respectively, in the real complex environment. Compared with the intra-system RTK/INS model, inter-system RTK/INS mode 3D positioning root-mean-square error is reduced by 79% in the simulated environment and by 27% in the real complex environment. In the single-epoch mode, the ambiguity success rates of the inter-system RTK/INS model, inter-system RTK model, intra-system RTK/INS model and intra-system RTK model are 89, 74, 69 and 58%, respectively, in the simulated environment, and 68, 41, 64 and 12%, respectively, in the real complex environment. Numéro de notice : A2023-003 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-022-01347-8 Date de publication en ligne : 09/10/2022 En ligne : https://doi.org/10.1007/s10291-022-01347-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101873
in GPS solutions > vol 27 n° 1 (January 2023) . - n° 3[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)
[article]
Titre : A nonlinear Gauss-Helmert model and its robust solution for seafloor control point positioning Type de document : Article/Communication Auteurs : Yingcai Kuang, Auteur ; Zhiping Lu, Auteur ; Fangchao Wang, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : pp 16 - 42 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] capteur ultrasonore
[Termes IGN] Chine
[Termes IGN] équation de Lagrange
[Termes IGN] erreur systématique
[Termes IGN] fond marin
[Termes IGN] GNSS-Acoustique
[Termes IGN] méthode robuste
[Termes IGN] modèle de Gauss-Helmert
[Termes IGN] modèle non linéaire
[Termes IGN] point d'appui
[Termes IGN] positionnement par GNSS
[Termes IGN] précision du positionnement
[Termes IGN] propagation d'erreurRésumé : (auteur) Using GNSS-Acoustic (GNSS-A) technology to establish the seafloor geodetic datum is both feasible and flexible and thus has become an important way to obtain the absolute positions of seafloor control points. However, numerous errors are inevitable in marine surveying, including systematic errors and gross errors caused by GNSS dynamic positioning, inaccurate sound velocity profile measurements, and ocean ambient noise, and their interference will be directly reflected in the positioning results. To accurately calculate the seafloor control point coordinates, this paper first notes that the general error propagation law (EPL) method is defective in dealing with various error factors in GNSS-A positioning. A more rigorous method incorporates the time-varying term of the sound velocity ranging error into the coefficient matrix of the underwater observation equation, and the transducer position error should be considered. Therefore, a Gauss-Helmert (GH) model is used for seafloor control point positioning. Then, considering the dual nonlinearity of the model, a Lagrange objective function is constructed to derive its solution algorithm. On this basis, considering the gross errors polluting of the observations, the robust estimation principle is introduced, and the robust solution steps are given. Finally, simulation experiments and a testing experiment in the sea area near Jiaozhou Bay are used to verify the performance of the new method. The results show that the functional relationship and stochastic model of the nonlinear GH model for seafloor point positioning are reasonably described. Under ideal conditions with no gross errors and either different water depths or different transducer position errors, the accuracy and stability of the new method are both higher than those of the EPL method. When the observations are polluted by gross errors, the robust algorithm of the new method can accurately identify the abnormal information. By improving the robustness of the observation and structure spaces, the positioning precision of the 3D point deviation results can be optimized, and the solution performance of the new method is superior to that of the general method. Numéro de notice : A2023-049 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1080/01490419.2022.2054883 Date de publication en ligne : 26/03/2022 En ligne : https://doi.org/10.1080/01490419.2022.2054883 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102365
in Marine geodesy > vol 46 n° 1 (January 2023) . - pp 16 - 42[article]Performance tests of geodetic receivers with tilt sensors in obstructed environments using the NRTK GNSS technique / Puttipol Dumrongchai in Journal of applied geodesy, vol 17 n° 1 (January 2023)
[article]
Titre : Performance tests of geodetic receivers with tilt sensors in obstructed environments using the NRTK GNSS technique Type de document : Article/Communication Auteurs : Puttipol Dumrongchai, Auteur ; Jittranud Patsadutarn, Auteur ; Chalermchon Satirapod, Auteur Année de publication : 2023 Article en page(s) : pp 39 - 51 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] centrale inertielle
[Termes IGN] Continuously Operating Reference Station network
[Termes IGN] délimitation
[Termes IGN] lever cadastral
[Termes IGN] microsystème électromécanique
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] récepteur GNSS
[Termes IGN] signal GNSS
[Termes IGN] station virtuelle de référence
[Termes IGN] ThaïlandeRésumé : (auteur) The Department of Lands (DOL), Thailand, has adopted the Network-based Real-Time Kinematic (NRTK) Global Navigation Satellite System (GNSS) surveying technique using a Virtual Reference Station (VRS) to support cadastral surveys since 2011. Determining accurate coordinates of parcel boundary markers at building corners or near fences and walls is difficult because a GNSS range pole cannot be leveled with a circular bubble. This study aims to evaluate the performance of the receivers equipped with tilt sensors for horizontal and vertical positioning. Two types of tilt sensors used for evaluation were a magnetometer and micro-electro-mechanical system (MEMS) and an inertial measurement unit (IMU). Conducting the NRTK GNSS surveying tests was based on the pole tilt angles of 0°, 15°, 25°, 35°, and 45° from a plumb line in controlled and obstructed environments. The IMU-based tilt sensor had more advantage of accurately positioning over the MEMS sensor. The results showed that using the IMU, better than 4 cm horizontal positioning accuracy was achievable when the pole was tilted by 15° or less under non-multipath and open-sky conditions. The vertical accuracy was of a few centimeter levels and least sensitive to tilt angles using either type of sensor. However, none of the sensors precisely compensated for pole tilt in strong-multipath and complex environments, causing increased horizontal errors in decimeter levels. Numéro de notice : A2023-111 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/jag-2022-0047 Date de publication en ligne : 07/11/2022 En ligne : https://doi.org/10.1515/jag-2022-0047 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102470
in Journal of applied geodesy > vol 17 n° 1 (January 2023) . - pp 39 - 51[article]Production of orthophoto map using mobile photogrammetry and comparative assessment of cost and accuracy with satellite imagery for corridor mapping: a case study in Manesar, Haryana, India / Manuj Dev in Annals of GIS, vol 29 n° 1 (January 2023)
[article]
Titre : Production of orthophoto map using mobile photogrammetry and comparative assessment of cost and accuracy with satellite imagery for corridor mapping: a case study in Manesar, Haryana, India Type de document : Article/Communication Auteurs : Manuj Dev, Auteur ; Shetru M. Veerabhadrappa, Auteur ; Ashutosh Kainthola, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : pp 163 - 176 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Orthophotographie, orthoimage
[Termes IGN] aérotriangulation
[Termes IGN] analyse comparative
[Termes IGN] image panoramique
[Termes IGN] image satellite
[Termes IGN] modèle stéréoscopique
[Termes IGN] orthoimage
[Termes IGN] orthophotocarte
[Termes IGN] point d'appui
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] système de numérisation mobileRésumé : (auteur) The study aims to find a low-cost alternate technology to get imagery, using mobile platform, and produce digital orthophoto for corridor mapping, with a higher degree of accuracy and which can reduce the lag time of acquisition of data. The present study uses digital single-lens reflex cameras, mounted on a mobile vehicle, and acquisition of data in the video format rather than still photographs, as traditionally used in mobile mapping systems. The videos are used to create a set of images and orthophotos. A widespread ground control points were recorded in the study area, using the global navigation satellite system receiver, which measured the control points in real-time kinematic mode. Generation of digital orthophoto has been completed using the captured mobile imagery and ground control point. Furthermore, procurement of satellite imagery and aerial triangulation using ground control points have been done. While comparing the planimetric accuracy of orthophoto against satellite imagery using the ground control points, the achieved root mean square error value of produced orthophoto is 0.171 m in X axis and 0.205 m in Y axis. However, for Cartosat -1 satellite imagery, the RMSE value for X is 1.22 m and for Y is 1.98 m. This research proposes the alternate low-cost mobile mapping method to capture the imagery for orthophoto production. The cost of orthophoto production from mobile image was found 77% cheaper than the orthophoto cost from fresh/latest satellite imagery procurement, while the overall production was 70% cost-effective than the orthophoto maps made from archived imagery. Numéro de notice : A2023-161 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1080/19475683.2022.2141853 Date de publication en ligne : 12/11/2022 En ligne : https://doi.org/10.1080/19475683.2022.2141853 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102864
in Annals of GIS > vol 29 n° 1 (January 2023) . - pp 163 - 176[article]A 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)PermalinkTree position estimation from TLS data using hough transform and robust least-squares circle fitting / Maja Michałowska in Remote Sensing Applications: Society and Environment, RSASE, vol 29 (January 2023)PermalinkGalileo High Accuracy Service (HAS) ou le service de haute précision de Galileo / Bernard Flacelière in XYZ, n° 173 (décembre 2022)PermalinkGeoreferencing accuracy assessment of historical aerial photos using a custom-built online georeferencing tool / Su Zhang in ISPRS International journal of geo-information, vol 11 n° 12 (December 2022)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)PermalinkIdentifying spurious cycle slips based on iterative filtering under disturbed ionospheric conditions for undifferenced GNSS observations / Yan Xiang in Advances in space research, vol 70 n° 11 (December 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)Permalink