Comparative analysis of data quality and performance index for BDS-3 constellation

The global BeiDou-3 Navigation Satellite System (BDS-3) was completed in July 2020. In terms of data processing, the final positioning and baseline solving results will be affected by the quality of the raw observation data. Therefore, it is necessary to analyse and evaluate the data quality of the complete BDS-3 constellation and its service performance. Based on all observing satellites and the open signals from MGEX stations that can track BDS-3, improved software is used to analyse the complete BDS-3 constellation and signals. Moreover, the service performance of BDS-3 is evaluated using self-developed software. The geometric configuration of the complete BDS-3 constellation is found to be slightly better than that of GPS. However, the overall multipath error is about 10 cm higher than that of GPS, although the increased choke of the measured maritime data effectively weakens the multipath error. The pseudorange multipath error of each signal runs in the order B1I>B2a>B2b>B3I>B2a+B2b>B1C; other quality indicators exhibit little difference among bands. In terms of service performance, the carrier phase residuals are 0.17-0.48cm. After data convergence, the relative positioning performance fluctuates around 5 cm of the “true value”, although the fluctuations in the vertical direction are up to 10 cm.