HR: 0800h
AN: G41B-0357    [Abstracts]
TI: Integrity Monitoring of IGS Satellite Orbits by Means of the RTIGS Network
AU: * WEBER, R
EM: rweber@mars.hg.tuwien.ac.at
AF: Inst. of Geodesy and Geophysics University of Technology, Vienna, Gusshausstrasse 27-29, Vienna, A-1040 Austria
AU: OPITZ, M
EM: mopitz@mars.hg.tuwien.ac.at
AF: Inst. of Geodesy and Geophysics University of Technology, Vienna, Gusshausstrasse 27-29, Vienna, A-1040 Austria
AB: Since the boom in mobile telecommunications allows Internet access for anyone anywhere at any time, this medium has also become an alternative method for transmitting GNSS data streams. Since 3 years the IGS (International GNSS Service) Real-Time Working Group exploits the options offered by the World Wide Web to disseminate raw observation data of a subset of stations of the IGS network as well as ephemeris and surface meteorological data. On the other hand this observation data can be used for a real time integrity monitoring of the GNSS-Broadcast orbits as well as for the IGS predicted orbits (Ultra Rapid Orbits). These satellite ephemeris demonstrate significantly higher accuracy (ñ10 cm) than the broadcast orbits (ñ 2m), but carry the risk of individual, recurring outliers. This presentation highlights the functionality of a software tool called ?RTR- Control?, developed at our institute for integrity monitoring. It allows for the comparison of pseudoranges measured at any permanent station in the global network with theoretical pseudoranges calculated on the basis of precise, predicted satellite orbits. Thus, the programme can diagnose incorrectly predicted satellite orbits as well as detect multi-path distorted pseudoranges in real- time. Among the user groups interested in integrity monitoring are the operating authorities and companies of GNSS station networks. Over the past years these networks matured to indispensable nationwide and continental realizations (e.g. EPN in Europe) of the terrestrial reference system. To calculate the network solution either the broadcast ephemeris or today very frequently the more precise predicted IGS orbits are used. RTR-Control can identify mismodelled satellites and prevent that observation data of this satellite is further used for the calculation of corrections which are passed to the RTK users within the network. Last but not least the IGS itself is obviously interested in a rigorous integrity monitoring of the issued orbital data.
DE: 1229 Reference systems
DE: 1241 Satellite geodesy: technical issues (6994, 7969)
SC: Geodesy [G]
MN: Fall Meeting 2005