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Mehrdimensionale Interpolation von Meteorologischen Feldern zur Berechnung der Brechungsbedingungen in der Geodäsie / Hans Arnold Hirter (1998)  

Public Titre : Mehrdimensionale Interpolation von Meteorologischen Feldern zur Berechnung der Brechungsbedingungen in der Geodäsie Titre original : [Interpolation multidimensionnelle de campagnes météorologiques pour le calcul des modalités de la réfraction en géodésie] Type de document : Thèse/HDR Auteurs : Hans Arnold Hirter, Auteur Editeur : Zurich : Institut für Geodäsie und Photogrammetrie IGP - ETH Année de publication : 1998 Collection : IGP Mitteilungen, ISSN 0252-9335 num. 064 Importance : 116 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-906467-11-5 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Rayonnement électromagnétique [Termes IGN] collocation [Termes IGN] correction troposphérique [Termes IGN] covariance [Termes IGN] interpolation [Termes IGN] propagation troposphérique [Termes IGN] réfraction [Termes IGN] réfraction atmosphérique [Termes IGN] signal GPS Index. décimale : 24.30 Rayonnement électromagnétique Résumé : (Auteur) The refractive effects in geodetic applications are known as unpleasant sources of errors. Microwave sources, as being used with Global Positioning System (GPS) are subjected to the physical laws of refraction when traversing the atmosphere. There are two methods to reduce the tropospheric error: The first is modeling the atmospheric effects and the second is to estimate the tropospheric parameters. Here we focus our attention on modeling of the troposphere. The magnitude of the effects depends upon the index of refraction and its spatial distribution as well as its temporal fluctuation. The index of refraction depends upon the frequency of the electromagnetic measuring beam and the actual state of the troposphere being relevant to refraction. The index of refraction can be described by the meteorological magnitudes such as pressure, temperature and humidity. If the refractive relationships are known respectively the values of the pressure, temperature and humidity alongside the entire beam the Path Delay can be determined for the latter. For calculating the Path Delay at an arbitrary location and arbitrary time the discrete meteorological data being sampled has to be inter- respectively extrapolated. Precisely this fact is being taken into account by the method of Krigings or Collocation. On the basis of arbitrarily distributed samples acquired in space and time, the collocation permits to execute a 4-dimensional modeling by taking into account simple approximated physical models. The deviation from this approximation is explained by the functional model with two stochastic segments (signal and noise). The physical model is adapted optimally to the measured values by the collocation. The zenith Path Delays (in the order of 2 m) calculated with the model can be inserted directly into the evaluation software of the GPS. As opposed to the standard models, the GPS-evaluation with Path Delays yields more consistent solutions which imply that the variance of the GPS solution is being reduced. Using the modeled Path Delays in the local Turtmann GPS testing-network with large height-differences, the repeatability of the height measurements is significantly increased (up to a factor of 2). Numéro de notice : 67046 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse étrangère DOI : 10.3929/ethz-a-001591486 En ligne : http://dx.doi.org/10.3929/ethz-a-001591486 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=61689

Exemplaires(2)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
67046-01	24.30	Livre	Centre de documentation	Physique	Disponible
67046-02	24.30	Livre	Centre de documentation	Physique	Disponible