On the Mátern covariance family:

a proposal for modeling temporal correlations based on turbulence theory

verfasst von
Gaël Kermarrec, Steffen Schön
Abstract

Current variance models for GPS carrier phases that take correlation due to tropospheric turbulence into account are mathematically difficult to handle due to numerical integrations. In this paper, a new model for temporal correlations of GPS phase measurements based on turbulence theory is proposed that overcomes this issue. Moreover, we show that the obtained model belongs to the Mátern covariance family with a smoothness of 5/6 as well as a correlation time between 125–175 s. For this purpose, the concept of separation distance between two lines-of-sight introduced by Schön and Brunner (J Geod 1:47–57, 2008a) is extended. The approximations made are highlighted as well as the turbulence parameters that should be taken into account in our modeling. Subsequently, fully populated covariance matrices are easily computed and integrated in the weighted least-squares model. Batch solutions of coordinates are derived to show the impact of fully populated covariance matrices on the least-squares adjustments as well as to study the influence of the smoothness and correlation time. Results for a specially designed network with weak multipath are presented by means of the coordinate scatter and the a posteriori coordinate precision. It is shown that the known overestimation of the coordinate precision is significantly reduced and the coordinate scatter slightly improved in the sub-millimeter level compared to solutions obtained with diagonal, elevation-dependent covariance matrices. Even if the variations are small, turbulence-based values for the smoothness and correlation time yield best results for the coordinate scatter.

Organisationseinheit(en)
Institut für Erdmessung
Typ
Artikel
Journal
Journal of geodesy
Band
88
ISSN
0949-7714
Publikationsdatum
02.07.2014
Publikationsstatus
Veröffentlicht
Peer-reviewed
Ja
ASJC Scopus Sachgebiete
Geophysik, Geochemie und Petrologie, Computer in den Geowissenschaften
Elektronische Version(en)
https://doi.org/10.1007/s00190-014-0743-7 (Zugang: Geschlossen)
 

Details im Forschungsportal „Research@Leibniz University“