Potentials for GNSS Signal Enhancements - An Assessment of the Impact of Satellite Imperfections on the Navigation Performance of Today's and Future GNSS

摘要

The launch of GPS space vehicle 49, at the latest, provided clear evidence to the GNSS community that satellite imperfections are very diverse and do not necessary match with the models used on ground for system development. Non-linearities, frequency selectivity, satellite inherent multipath and even elevation dependent signal distortions have to be considered - only to mention some of the drawbacks seen on today's satellites. Those imperfections are quite common and can be found on a multitude of GNSS satellites. It is the aim of this paper to learn from the performance of the signal transmission payloads of the GNSS satellites already in orbit in order to better understand payload limitations and signal imperfections in real environments. It is the intention to characterize typical payload imperfections for using them in the context of receiver performance assessment and optimization as well as for the design of future GNSS signals.