Analysis of BDS-3 and BDS-2 Satellite Multipath Error

BDS-3 has been providing initial service from December 2018. BDS entered the stage of simultaneous service with 2 generations of satellites: BDS-2 and BDS-3. There are three different orbit for BDS satellites including GEO, IGSO and MEO, and 4 open service signals including B1I, B2I, B3I, B1C and B2a. Compared with BDS-2, the on-board payload of the BDS-3 has been redesigned, and the parameters of signals are designed to be better, especially in multipath mitigation. In order to verify the performance of BDS-3 signals in terms of multipath errors, we use data from the “international GNSS Monitoring and Assessment System (iGMAS)” multi-GNSS observation stations to analyze the multipath errors of BDS-2 and BDS-3. The results show that the pseudorange multipath error of BDS-2 has a systematic bias that varies with the elevation angle, and the performance of B3I signals is better than B1I for BDS-2 satellites. While B1I, B3I, B1C, and B2a signals of BDS-3 satellites have pseudorange multipath errors with zero mean characteristic, and BDS-3 B1I, B3I signals multipath error is significantly better than BDS-2. The B3I and B2a signals have better performance than B1I and B1C for BDS-3 satellites.