Centre de documentation
scientifique

Dépouillements

Study of external path delay correction techniques for high accuracy height determination with GPS / Olivier Bock in Physics and chemistry of the Earth, Part A: Solid Earth and Geodesy, vol 26 n° 3 ([01/03/2001])  

Public [article]  inPhysics and chemistry of the Earth, Part A: Solid Earth and Geodesy > vol 26 n° 3 [01/03/2001] . - pp 165 - 171 Titre : Study of external path delay correction techniques for high accuracy height determination with GPS Type de document : Article/Communication Auteurs : Olivier Bock , Auteur ; Jérôme Tarniewicz , Auteur ; Christian Thom , Auteur ; Jacques Pelon, Auteur ; Michel Kasser , Auteur Année de publication : 2001 Article en page(s) : pp 165 - 171 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale [Termes IGN] lidar Raman [Termes IGN] précision du positionnement [Termes IGN] résidu [Termes IGN] retard ionosphèrique [Termes IGN] retard troposphérique [Termes IGN] teneur en vapeur d'eau [Termes IGN] traitement de données GNSS Résumé : (auteur) For specific applications such as permanent GPS network calibration and national leveling network surveying, a vertical accuracy of ∼1 mm for observing durations of a few hours to a few days at maximum in 10–100-km baselines would be required. To achieve a 1-mm accuracy in height determinations with differential-GPS measurements, path delay must be corrected with an accuracy of ∼0.3 mm. This level of accuracy is not achievable with standard GPS data analysis procedures. External correction from a water vapor remote sensing technique is therefore necessary. Microwave radiometers, which have been most extensively used for this purpose, solar spectrometers, DIAL and Raman lidars are considered in this paper. The principle and performance of these techniques is reviewed in the context of wet path delay retrieving. Namely, we evaluate the errors arising during the conversion of raw measurements to wet path delay, using retrieval coefficients or standard profiles. It is shown that changes in temperature profiles can produce errors of up to 1 cm in wet path delay with microwave radiometers. Similarly, mismodeled temperature profiles can produce errors of 2–3 mm in wet path delay with DIAL and Raman lidars. Raman lidar offers the possibility to retrieve the temperature profile from total air density. Assuming that absolute concentrations of water vapor and dry gases can be retrieved, the accuracy would be unbiased. In addition, Raman lidar would also allow for the correction of hydrostatic path delay without requiring the use of mapping functions. This might reduce the residual errors due to horizontal pressure and temperature gradients. This technique will therefore be investigated in more details in a future study. Numéro de notice : A2001-261 Affiliation des auteurs : LOEMI+Ext (1985-2011) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/S1464-1895(01)00041-2 Date de publication en ligne : 07/05/2001 En ligne : https://doi.org/10.1016/S1464-1895(01)00041-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103207 [article]