Multipath Effect Evaluation and Orbit Determination Accuracy Analysis for BDS-3 B1C&B2a Signals

In addition to broadcasting the original B1I&B3I signals, BDS-3 MEO and IGSO satellites newly broadcast the B 1 C&B2a frequency signals. With the official opening of the BeiDou global satellite navigation system, the number of stations capable of receiving new frequency signals has gradually increased. Using the observation data of International GNSS Monitoring & Assessment System (iGMAS) and Multi-GNSS experiment (MGEX) stations, the ranging accuracy of the BDS-3 B1C&B2a signals was analyzed, and the BDS-3 satellites orbit determination test was carried out using the new frequency data. The POD accuracy was evaluated by means of overlapping arcs and SLR validation. The results show that the multipath errors of the iGMAS station for the new signals are 0.35 m and 0.22 m, respectively. The three-dimensional overlapping arcs accuracy of BDS-3 satellites with B1C&B2a observations reaches 0.035 m. The RMS of SLR validation residuals is 0.055m, and the station coordinates accuracy in static precise point positioning (PPP) reaches 9.16 mm, which is equivalent to that of B1I&B3I signals.