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Where are we? (3) / Lewis Graham in GEO: Geoconnexion international, vol 14 n° 8 (September 2015)
[article]
Titre : Where are we? (3) Type de document : Article/Communication Auteurs : Lewis Graham, Auteur Année de publication : 2015 Article en page(s) : pp 31 - 33 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] drone
[Termes IGN] géolocalisation
[Termes IGN] lever aérienRésumé : (auteur) In the third of his series looking at getting the most from UAVs, Lewis Graham reports on his experiments in using on-board technologies to obtain surveygrade positioning information. Numéro de notice : A2015-476 Affiliation des auteurs : non IGN Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77201
in GEO: Geoconnexion international > vol 14 n° 8 (September 2015) . - pp 31 - 33[article]Reduction of PPP convergence period through pseudorange multipath and noise mitigation / Garrett Seepersad in GPS solutions, vol 19 n° 3 (July 2015)
[article]
Titre : Reduction of PPP convergence period through pseudorange multipath and noise mitigation Type de document : Article/Communication Auteurs : Garrett Seepersad, Auteur ; Sunil Bisnath, Auteur Année de publication : 2015 Article en page(s) : pp 369 - 379 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] bruit atmosphérique
[Termes IGN] correction du trajet multiple
[Termes IGN] filtrage du bruit
[Termes IGN] mesurage de pseudo-distance
[Termes IGN] positionnement ponctuel précis
[Termes IGN] trajet multipleRésumé : (auteur) Pseudorange multipath and pseudorange noise are the largest remaining unmanaged error sources in PPP. It is proposed that by reducing the effects of multipath and noise on the pseudorange observable, accurate estimates of carrier phase float ambiguities will be attained sooner, thus reducing the initial convergence period of PPP. Given the problem, this study seeks to improve mitigation of the pseudorange errors. The well-known multipath linear combination is used in two distinct ways: (1) to directly correct the raw pseudorange observables and (2) to stochastically de-weight the pseudorange observables. The improvements in the solution were calculated with respect to the conventional GPS PPP float solution, where the raw pseudorange observables were not modified or stochastically de-weighted. Corrections to the observables were made using the multipath linear combination from data obtained from the previous and same day. Minimal improvements were noted using the multipath observable from the previous day. Using the multipath observable from the same day was possible in real-time and post-processing modes, showing an improvement in the rate of convergence for 48 and 57 % of the data, respectively. An improvement in the rate of convergence for 34 % of the data was observed when the pseudorange measurements were stochastically de-weighted using the multipath observable. Datasets with no improvements from directly correcting the raw pseudorange observables (43 %) or stochastically de-weighting the pseudorange observables (66 %) presented similar quality of results as the conventional PPP solution. Numéro de notice : A2015-461 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-014-03 Date de publication en ligne : 01/08/2014 En ligne : https://doi.org/10.1007/s10291-014-0395-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77136
in GPS solutions > vol 19 n° 3 (July 2015) . - pp 369 - 379[article]The mixed-receiver BeiDou inter-satellite-type bias and its impact on RTK positioning / Nandakumaran Nadarajah in GPS solutions, vol 19 n° 3 (July 2015)
[article]
Titre : The mixed-receiver BeiDou inter-satellite-type bias and its impact on RTK positioning Type de document : Article/Communication Auteurs : Nandakumaran Nadarajah, Auteur ; Peter J.G. Teunissen, Auteur ; Jean-Marie Sleewaegen, Auteur ; Oliver Montenbruck, Auteur Année de publication : 2015 Article en page(s) : pp 357 - 368 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] erreur systématique
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] récepteur mixte
[Termes IGN] récepteur monofréquence
[Termes IGN] résolution d'ambiguïté
[Termes IGN] signal BeiDouRésumé : (Auteur) The inter-satellite-type bias (ISTB) is a receiver-dependent hardware delay/bias between different satellite types. Our recent research revealed the existence of nonzero mixed-receiver phase ISTBs for the Chinese BeiDou system. Triggered by this finding, global navigation satellite system receiver manufactures, who are in the early stage of BeiDou-enabled receiver developments, are working toward a mutually consistent measurement extraction procedure. We analyze the long-term stability and current status of the mixed-receiver ISTBs, as well as study their impact on BeiDou stand-alone real-time kinematic (RTK) positioning. Our results confirm that a recent update in one of the receiver types has aligned it with one of the other receiver types. However, since not all receiver types are aligned yet, nonzero mixed-receiver ISTBs are shown to be still present. Analyses of BeiDou stand-alone RTK positioning using mixed-receiver types demonstrate that ISTBs could seriously affect the integer ambiguity resolution performance and that a priori correction for these biases will dramatically improve the success rate. Our analyses using real data from three different receiver types also demonstrate the long-term stability of the ISTBs, thus showing that such a priori calibration is indeed possible. Numéro de notice : A2015-460 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-014-0392-6 Date de publication en ligne : 28/06/2014 En ligne : https://doi.org/10.1007/s10291-014-0392-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77130
in GPS solutions > vol 19 n° 3 (July 2015) . - pp 357 - 368[article]Detection of high speed railway track static regularity with laser trackers / L. Yao in Survey review, vol 47 n° 343 (July 2015)
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Titre : Detection of high speed railway track static regularity with laser trackers Type de document : Article/Communication Auteurs : L. Yao, Auteur ; H. Sun, Auteur ; Y. Zhou, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 279 - 285 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] capteur à balayage
[Termes IGN] précision submillimétrique
[Termes IGN] statique
[Termes IGN] surveillance d'ouvrage
[Termes IGN] train à grande vitesse
[Termes IGN] voie ferréeRésumé : (auteur) Track regularity is of vital importance in the safety of high speed railway operation. A laser tracker can collect highly accurate three-dimensional (3D) point measurements. Therefore, it is considered as a promising surveying technique for the detection of railway track static irregularity as opposed to using a total station. This study proposes a new approach that uses a laser tracker as the main sensor for obtaining the coordinates of left- and right-track points to detect potential track static irregularities. In this method, the reflecting target of the laser tracker is on a track inspection trolley moving in a round trip along the railway track. A field experiment was conducted to validate the results by comparing the results with the field measurements gathered using a track inspection trolley. The results show that the track static regularity detection method with laser trackers is feasible and indicate that track geometry parameters such as gauges, elevations and lateral deviations of centreline, superelevations, lateral profiles and vertical profiles obtained using the laser tracker and a track inspection trolley are in a good agreement. The average of deviations of track centreline elevations, lateral deviations, and gauges are 0·8, 0·7 and 0·3 mm. Numéro de notice : A2015-922 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1179/1752270614Y.0000000135 En ligne : https://doi.org/10.1179/1752270614Y.0000000135 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79733
in Survey review > vol 47 n° 343 (July 2015) . - pp 279 - 285[article]Divisional ambiguity resolution for long range reference stations in network RTK / J. Deng in Survey review, vol 47 n° 343 (July 2015)
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Titre : Divisional ambiguity resolution for long range reference stations in network RTK Type de document : Article/Communication Auteurs : J. Deng, Auteur ; S.L. Wang, Auteur Année de publication : 2015 Article en page(s) : pp 272 - 278 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] analyse comparative
[Termes IGN] fractionnement
[Termes IGN] ligne de base
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] résolution d'ambiguïté
[Termes IGN] station permanenteRésumé : (auteur) Increasing the distance between reference stations of network RTK can improve the flexibility of the reference stations sitting, reduce the number of reference stations and cut down construction and maintenance costs. However, it also decreases the correlation of spatial error and affects the real time performance and effectiveness of the network RTK positioning. Thus, the key techniques of long range network RTK need to be further optimised. Ambiguity resolution between reference stations is one of the most critical techniques. In this paper a divisional ambiguity resolution for long range reference stations of network RTK is proposed, so as to deal with the long fixed time and low success rate, especially for low elevation satellites. Based on conventional two-step ambiguity resolution, firstly, this new method calculates the wide-lane ambiguity by building M-W combination of pseudo-range and carrier observations. Second, the conventional ambiguity resolution as a whole is changed and satellites are divided into high elevation ones and low elevation ones, then the integer ambiguity of high elevation satellites is resolved by means of ionosphere-free combination with the relative zenith wet delay as a parameter. Finally, the Kalman filter model is established by the observation equation of high elevation satellites with calculated ambiguity and low elevation satellites, assisting to obtain the ambiguity of low elevation satellites quickly. The example selects a 196 km long baseline for comparative analysis. Result shows that it takes 733 s to resolve the ambiguity of all satellites by conventional ambiguity resolution in whole, and 252 s by divisional ambiguity resolution proposed in this paper. The new method saves about two thirds of resolution time, and also greatly improves the efficiency of ambiguity resolution of low elevation satellites for long baseline. Numéro de notice : A2015-921 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1179/1752270614Y.0000000123 En ligne : https://doi.org/10.1179/1752270614Y.0000000123 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79732
in Survey review > vol 47 n° 343 (July 2015) . - pp 272 - 278[article]Seeing the light: a vision-aided integrity for precision relative navigation systems / Sean Calhoun in GPS world, vol 26 n° 7 (July 2015)PermalinkStreet smart: 3-D city mapping and modeling for positioning with multi-GNSS / Li-Ta Hsu in GPS world, vol 26 n° 7 (July 2015)PermalinkWeighted total least squares for solving non-linear problem: GNSS point positioning / S. Jazaeri in Survey review, vol 47 n° 343 (July 2015)PermalinkBienvenue en Terra Indoora / Françoise de Blomac in DécryptaGéo le mag, n° 168 (juin 2015)PermalinkImpact of ocean tides loading on precise point positioning based on FES2004 model / J.Z. Kalita in Artificial satellites, vol 50 n° 2 (June 2015)PermalinkNovel integration strategy for GNSS-aided inertial integrated navigation / Kun Qian in Geomatica, vol 69 n° 2 (June 2015)PermalinkA la recherche du point bleu / Françoise de Blomac in DécryptaGéo le mag, n° 168 (juin 2015)PermalinkSuivez le guide / Françoise de Blomac in DécryptaGéo le mag, n° 168 (juin 2015)PermalinkDistant positioning for GNSS securing / Marc Revol in Navigation aérienne, maritime, spatiale, terrestre, vol 62 n° 247 (mai 2015)PermalinkEfficient obstruction analysis for GNSS relative positioning of terrestrial mobile mapping system / J.Y. Han in Survey review, vol 47 n° 342 (May 2015)PermalinkLocal GNSS monitoring / A. Guilloton in Navigation aérienne, maritime, spatiale, terrestre, vol 62 n° 247 (mai 2015)PermalinkPositioning, navigation, and timing (PNT): governance, required improvements / Dana Allen Goward in Navigation aérienne, maritime, spatiale, terrestre, vol 62 n° 247 (mai 2015)PermalinkAutomatic selection of landmarks for navigation guidance / Rui Zhu in Transactions in GIS, vol 19 n° 2 (April 2015)PermalinkAn innovative dual frequency PPP model for combined GPS/Galileo observations / Akram Afifi in Journal of applied geodesy, vol 9 n° 1 (March 2015)PermalinkPerformance analysis of GPS / GALILEO PPP model for static and kinematic applications / Mahmoud Abd-El-Rahman in Geomatica, vol 69 n° 1 (March 2015)PermalinkPositioning in challenging environments using ultra-wideband sensor networks / Zoltan Koppanyi in GPS world, vol 26 n° 3 (March 2015)PermalinkPrecise point positioning using multi-constellation GNSS observations for kinematic applications / Mahmoud Abd-El-Rahman in Journal of applied geodesy, vol 9 n° 1 (March 2015)PermalinkReview and principles of PPP-RTK methods / Peter J.G. Teunissen in Journal of geodesy, vol 89 n° 3 (March 2015)PermalinkPython GNSS receiver: An object-oriented software platform suitable for multiple receivers / Eliot Wycoff in GPS world, vol 26 n° 2 (February 2015)PermalinkEvaluation of Precise Point Positioning accuracy under large total electron content variations in equatorial latitudes / I. Rodriguez-Bilbao in Advances in space research, vol 55 n° 2 (January 2015)Permalink