Analysis and modeling of GLONASS broadcast ephemeris errors

One of the most problems in GNSS application is to obtained high precision ephemeris. In this paper, the error characters of GLONASS broadcast ephemeris (GBE) are analyzed carefully. one week data of all healthy orbiting satellites from GBE are calculated and their errors are figured out. The result shows that there are some obvious periodic varieties in the errors of GBE. Therefore, the main periods can be obtained by FFT and spectrum analysis. A new compensation model has been constructed. To verify the validation of the model, an experiment is done with GBE data of 7 days. The results show that the proposed model can improve the precision of GBE by 2-3 times, even 7-8 times. It is very important to improve the precision of GLONASS real time positioning. Moreover, this method can also be applied to COMPASS. © 2012 Springer-Verlag GmbH.