Open AccessA collocation framework to retrieve tropospheric delays from a combination of GNSS and InSAR
Author(s) -
Shehaj Endrit,
Wilgan Karina,
Frey Othmar,
Geiger Alain
Publication year - 2020
Publication title -
navigation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.847
H-Index - 46
eISSN - 2161-4296
pISSN - 0028-1522
DOI - 10.1002/navi.398
Subject(s) - interferometric synthetic aperture radar , gnss applications , remote sensing , troposphere , zenith , satellite , synthetic aperture radar , satellite system , environmental science , computer science , collocation (remote sensing) , geodesy , numerical weather prediction , meteorology , global positioning system , geology , geography , telecommunications , engineering , aerospace engineering
Abstract High spatio‐temporal variability of atmospheric water vapor affects microwave signals of Global Navigation Satellite Systems (GNSS) and Interferometric Synthetic Aperture Radar (InSAR). A better knowledge of the distribution of water vapor improves both GNSS‐ and InSAR‐derived data products. In this work, we present a collocation framework to combine and retrieve zenith and (relative) slant tropospheric delays. GNSS and InSAR meteorological products are combined aiming at a better retrieval of the atmospheric water vapor. We investigate the combination approach with synthetic and real data acquired in the Alpine region of Switzerland. Based on a closed‐loop validation with simulated delays, a few mm accuracy is achieved for the GNSS‐InSAR combination in terms of retrieved ZTDs. Furthermore, when real delays are collocated, the combination results are more congruent with InSAR computed products. This research is a contribution to improve the spatio‐temporal mapping of tropospheric delays by combining GNSS‐derived and InSAR‐derived delays.