GPS and Galileo Performance Evaluations for Multiple Reference Network Real-Time Positioning

摘要

The European Galileo system and the modernization of the current Global Positioning System (GPS) will substantially increase the available signals to Global Navigation Satellite Systems (GNSS) users. Past simulation studies have shown that Galileo performs better than GPS for high ionospheric conditions and for medium length baselines for the Single Reference Station (SRS) approach. When the baseline increases beyond 30 km, the ambiguity resolution performance deteriorates, and RTK positioning becomes difficult to achieve for either system. The Multiple Reference Station (MRS) approach reduces the effect of correlated errors much more effectively than the traditional SRS approach and hence provides better positioning accuracy over increased baseline distances. The Multiple Reference Station Tightly Coupled (MRS-TC) approach is an efficient MRS technique developed at the University of Calgary. This paper extends past research through an evaluation of Galileo compared to GPS for the MRS approach. This study focuses on a comparison assessment of the MRSTC approach for dual frequency Galileo and GPS systems independently in terms of positioning accuracy and ambiguity resolution. Several networks of varying sizes are tested under different ionospheric conditions using a measurement simulation software system.