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A highly adaptable method for GNSS cycle slip detection and repair based on Kalman filter / Xianwen Yu in Survey review, Vol 53 n° 377 (February 2021)
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Titre : A highly adaptable method for GNSS cycle slip detection and repair based on Kalman filter Type de document : Article/Communication Auteurs : Xianwen Yu, Auteur ; Siqi Xia, Auteur Année de publication : 2021 Article en page(s) : pp 169 - 182 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes descripteurs IGN] compensation Lambda
[Termes descripteurs IGN] détection
[Termes descripteurs IGN] double différence
[Termes descripteurs IGN] filtre de Kalman
[Termes descripteurs IGN] glissement de cycle
[Termes descripteurs IGN] phase
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) The cycle slip detection and repair are crucial steps in the preprocessing of GNSS carrier phase observation. Currently, however, there are few cycle slip detection and repair methods that can meet the data processing needs for diverse situations. To solve this problem, a highly adaptable cycle slip detection and repair method is proposed. First, a cycle slip detection equation is established using the pseudo-range and carrier double-differenced (DD) observations; the state equation is developed based on the satellite-ground distance. Then, a Kalman filter estimation model is established by joining the two equations. Subsequently, the cycle slip can be detected and repaired. Finally, the state parameters are refined in accordance with the conditional distribution. According to the results of the example, all the simulated cycle slips are detected and repaired by the method proposed. It shows that the method can meet the data processing needs for multiple situations. Numéro de notice : A2021-195 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2020.1756107 date de publication en ligne : 29/04/2020 En ligne : https://doi.org/10.1080/00396265.2020.1756107 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97133
in Survey review > Vol 53 n° 377 (February 2021) . - pp 169 - 182[article]Integer-estimable GLONASS FDMA model as applied to Kalman-filter-based short- to long-baseline RTK positioning / Pengyu Hou in GPS solutions, Vol 24 n° 4 (October 2020)
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Titre : Integer-estimable GLONASS FDMA model as applied to Kalman-filter-based short- to long-baseline RTK positioning Type de document : Article/Communication Auteurs : Pengyu Hou, Auteur ; Baocheng Zhang, Auteur ; Teng Liu, Auteur Année de publication : 2020 Article en page(s) : 14 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes descripteurs IGN] compensation Lambda
[Termes descripteurs IGN] données GLONASS
[Termes descripteurs IGN] données GPS
[Termes descripteurs IGN] filtre de Kalman
[Termes descripteurs IGN] ionosphère
[Termes descripteurs IGN] ligne de base
[Termes descripteurs IGN] positionnement cinématique en temps réel
[Termes descripteurs IGN] positionnement par GLONASS
[Termes descripteurs IGN] résolution d'ambiguïté
[Termes descripteurs IGN] signal GLONASSRésumé : (auteur) Fast ambiguity resolution is a major challenge for GLONASS phase-based applications. The integer-estimable frequency-division multiple-access (IE-FDMA) model succeeds in formulating a set of estimable GLONASS phase ambiguities and preserving the integer property, to which the classical integer ambiguity resolution, typically the least-squares ambiguity decorrelation adjustment (LAMBDA), becomes readily applicable. The initial assessment of the IE-FDMA model demonstrated instantaneous ambiguity resolution capability in case of short-baseline real-time kinematic (RTK) positioning based on ionosphere-fixed formulation, in which the data processing strategy is window (batch)-based least-squares estimation with window length ranging from one to a few epochs. Here, we extend the applicability of the IE-FDMA model to Kalman-filter-based, ionosphere-fixed, ionosphere-weighted, and ionosphere-free cases, which are, respectively, adoptable for short-, medium-, and long-baseline RTK positioning. To adapt the IE-FDMA model to the Kalman filter, we estimate, at each epoch, first the estimable ambiguities, then transform them into integer-estimable ones, and finally resolve them into correct integers. This enables the rigorous integer ambiguity resolution and, at the same time, eases the recursive construction of integer-estimable ambiguities. We analyze global positioning system (GPS) and GLONASS data of nine baselines with lengths varying from several meters to more than one hundred kilometers. The results demonstrate the feasibility of fast ambiguity resolution not only for the GLONASS phase-only short-baseline RTK positioning, but for the GPS + GLONASS medium- and long-baseline RTK positioning as well. In all cases, the fixed solution with faster (several-minutes) convergence and higher (centimeter-level) precision indicates the benefits from GLONASS ambiguity resolution as compared to the float solution. Moreover, the dual-system solution with decreased ambiguity dilution of precision (ADOP) and improved positioning precision confirms the advantages of integrating GLONASS with GPS in contrast to the GPS-only situation. Numéro de notice : A2020-524 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-020-01008-8 date de publication en ligne : 11/07/2020 En ligne : https://doi.org/10.1007/s10291-020-01008-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95699
in GPS solutions > Vol 24 n° 4 (October 2020) . - 14 p.[article]Performance of BDS triple-frequency positioning based on the modified TCAR method / Yijun Tian in Survey review, vol 52 n° 374 (August 2020)
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Titre : Performance of BDS triple-frequency positioning based on the modified TCAR method Type de document : Article/Communication Auteurs : Yijun Tian, Auteur ; Lifen Sui, Auteur ; Dongqing Zhao, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 415 - 422 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes descripteurs IGN] compensation Lambda
[Termes descripteurs IGN] filtre de Kalman
[Termes descripteurs IGN] positionnement par BeiDou
[Termes descripteurs IGN] précision du positionnement
[Termes descripteurs IGN] résolution d'ambiguïté
[Termes descripteurs IGN] retard ionosphèrique
[Termes descripteurs IGN] triple différenceRésumé : (auteur) A modified TCAR method to improve the NL ambiguity resolution over medium-long baseline is presented. The estimated DD ionospheric delay derived from the Kalman-filter floating solution is adopted to modify the floating NL ambiguities. Modified by the smooth DD ionospheric delay, the NL ambiguity residuals are mostly within 0.5 cycles over medium-long baselines, showing a significant improvement in contrast to the classical TCAR method. The positioning performances of the modified method are even better than the LAMBDA method over 72 and 634 km baselines. As the ambiguity can be correctly fixed just after several epochs, high-precision positioning can be achieved in a very short time. Numéro de notice : A2020-517 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2019.1627507 date de publication en ligne : 12/06/2019 En ligne : https://doi.org/10.1080/00396265.2019.1627507 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95677
in Survey review > vol 52 n° 374 (August 2020) . - pp 415 - 422[article]Effect of spatial correlation on the performances of modernized GPS and Galileo in relative positioning / Noureddine Kheloufi in Geodesy and cartography, vol 46 n° 2 (July 2020)
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Titre : Effect of spatial correlation on the performances of modernized GPS and Galileo in relative positioning Type de document : Article/Communication Auteurs : Noureddine Kheloufi, Auteur ; Abdelhalim Niati, Auteur Année de publication : 2020 Article en page(s) : pp 89 - 97 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes descripteurs IGN] compensation Lambda
[Termes descripteurs IGN] corrélation automatique de points homologues
[Termes descripteurs IGN] double différence
[Termes descripteurs IGN] estimation de quantité
[Termes descripteurs IGN] fréquence multiple
[Termes descripteurs IGN] ligne de base
[Termes descripteurs IGN] modèle stochastique
[Termes descripteurs IGN] positionnement différentiel
[Termes descripteurs IGN] positionnement par BeiDou
[Termes descripteurs IGN] positionnement par Galileo
[Termes descripteurs IGN] positionnement par GPS
[Termes descripteurs IGN] résolution d'ambiguïté
[Termes descripteurs IGN] retard ionosphèriqueRésumé : (auteur) In the context of processing GNSS (Global Navigation Satellite System) data, it is known that the estimation of the ionospheric delays decreases the strength of the observation model and makes significant the time required to fix the ambiguities namely in case of long baselines. However, considering the double-differenced (DD) ionospheric delays as stochastic quantities, the redundancy in this case increases and leads to the reduction of time of fixing the ambiguities. The approach developed in the present paper makes two considerations: 1) the DD ionospheric delays are assumed as stochastic quantities and, 2) the spatial correlation of errors is accounted for based on a simple model of correlation. A simulation is made and aims to study the effect of these two mentioned considerations on the performances of the three multifrequency GNSSs; modernized GPS, Galileo and BDS which are not yet in full capability. For each GNSS, dual-frequency combinations of frequencies as well as triple-frequency combination are investigated in the simulation. The performances studied include: the time to fix the ambiguities with high success rate and the precision of coordinates in static relative positioning with varying baseline length. A method is developed to derive what we call the spatial correlation model which approximately gives the covariance between the individual errors belonging to two stations. Furthermore, the stochastic models that follow from accounting and neglecting the spatial correlation are developed. The LAMBDA (Least-squares Ambiguity Decorrelation Adjustment) method is implemented for ambiguity decorrelation. The results show that the time to fix the ambiguities caused by accounting the spatial correlation is less than the time of fix without the spatial correlation. Also, a slight superiority of Galileo in terms of performances is seen compared to the other GNSS. For all the dualfrequency combinations investigated, when processing a baseline length of 500 km with accounted spatial correlation, the time needed to successfully fix the ambiguities lies between 5 and 9 min, whereas it becomes only between 2.5 and 3 min for all the triple-frequency combinations, this is with a sampling time of 5 s. In addition, for all different combinations, the coordinates precision is less than 8 mm even for 500 km. We think that these high performances result from: 1) the precise codes of future GNSS signals, 2) the high redundancy in the observations equation and, 3) taking into account the spatial correlation in the definition of the stochastic model. Numéro de notice : A2020-781 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3846/gac.2020.11009 date de publication en ligne : 15/07/2020 En ligne : https://doi.org/10.3846/gac.2020.11009 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96475
in Geodesy and cartography > vol 46 n° 2 (July 2020) . - pp 89 - 97[article]On-the-fly ambiguity resolution involving only carrier phase measurements for stand-alone ground-based positioning systems / Tengfei Wang in GPS solutions, vol 23 n° 2 (April 2019)
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Titre : On-the-fly ambiguity resolution involving only carrier phase measurements for stand-alone ground-based positioning systems Type de document : Article/Communication Auteurs : Tengfei Wang, Auteur ; Zheng Yao, Auteur ; Mingquan Lu, Auteur Année de publication : 2019 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes descripteurs IGN] ambiguïté entière
[Termes descripteurs IGN] compensation Lambda
[Termes descripteurs IGN] double différence
[Termes descripteurs IGN] mesurage de phase
[Termes descripteurs IGN] positionnement absolu
[Termes descripteurs IGN] positionnement ponctuel précis
[Termes descripteurs IGN] résolution d'ambiguïté
[Termes descripteurs IGN] station permanenteRésumé : (Auteur) Despite the wide use of the global navigation satellite system (GNSS), its performance can be severely degraded due to blockage and vulnerability to interference. Stand-alone ground-based positioning systems can provide positioning services in the absence of GNSS signals and have tremendous application potential. For precise point positioning in ground-based systems, ambiguity resolution (AR) is a key issue. On-the-fly (OTF) AR methods are desirable for reasons of convenience. The existing methods usually linearize a nonlinear problem approximately by a series expansion that is based on an initial position estimation obtained by code measurements or measuring instruments. However, if the initial position estimation contains relatively large errors, the convergence of existing methods cannot be ensured. We present a new OTF-AR method based on the double difference square (DDS) observation model for ground-based precise point positioning, which involves only carrier phase measurements. The initial solution obtained from the DDS model is sufficiently accurate to obtain a float solution by linearization, and this step only requires the frequency synchronization of base stations. Further, if the clock differences of the base stations are accurately calibrated, a fixed solution can be obtained by employing the LAMBDA algorithm. Numerical simulations and a real-world experiment are conducted to validate the proposed method. Both the simulations and the experimental results show that the proposed method can achieve high-accuracy positioning. These results enable precise point positioning to be applied in situations where no reliable code measurements or other measuring instruments are available for stand-alone ground-based positioning systems. Numéro de notice : A2019-058 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-019-0825-3 date de publication en ligne : 02/02/2019 En ligne : http://dx.doi.org/10.1007/s10291-019-0825-3 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92090
in GPS solutions > vol 23 n° 2 (April 2019)[article]Benefits of the third frequency signal on cycle slip correction / Xiaohong Zhang in GPS solutions, vol 20 n° 3 (July 2016)
PermalinkPerformance analysis of triple-frequency ambiguity resolution with BeiDou observations / Xiaohong Zhang in GPS solutions, vol 20 n° 2 (April 2016)
PermalinkPermalinkGeneralized integer aperture estimation for partial GNSS ambiguity fixing / Andreas Brack in Journal of geodesy, vol 88 n° 5 (May 2014)
PermalinkRapid static positioning using GPS and GLONASS / Gerhard Beutler in Bulletin of geodesy and geomatics BGG, vol 69 n° 2 - 3 (December 2010)
PermalinkPermalinkPermalinkPermalinkApplication des méthodes de résolution d'ambigüités sur la mesure de phase GPS à l'approche de précision / J.P. Chauveau (2002)
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