Abstract:
Objectives BeiDou navigation satellite system (BDS) officially opened its global service and it is essential to evaluate the BDS-3 global positioning performance in detail. Based on multi-day measured data from 16 MGEX tracking stations around the world.
Methods Net_Diff software was used to carry out the single point positioning solution experiment by BDS-3 single-frequency, dual-frequency non-combined and ionospheric-free-combined pseudorange, and triple-frequency non-combined and ionospheric-free-pairwise pseudorange.
Results The results show that the number of satellites and spatial geometry of BDS-3 in Asia, Europe and Africa are better than GPS and Galileo. In single-frequency, the horizontal and vertical positioning accuracy of B1C, B1I, B2a and B3I is at m level. Compared with GPS and Galileo, the positioning accuracy relationship is B1C > B1I > L1 > B3I > B2a > E1 > L2 > E5a. In dual-frequency combination, B2aB3I has a poor positioning accuracy and is not suitable for positioning. But B1CB2a, B1CB3I, B1IB2a and B1IB3I have better positioning accuracies. Compared with GPS and Galileo, the positioning accuracy relationship is B1CB2a > B1CB3I > L1L2 > B1IB3I > B1IB2a > E1E5a > B2aB3I. In triple-frequency combination, the positioning accuracy of B1IB2aB3I and B1CB2aB3I is better than 1 m in horizontal direction, and is better than 2 m in altitude direction. Compared with GPS and Galileo, the positioning accuracy relationship is B1CB2aB3I > B1IB2aB3I > L1L2L5 > E1E5aE5b. B1CB3I, B1IB3I, B1CB2a, B1IB2a are suitable for positioning using non-combined models, B2aB3I is suitable for positioning using ionospheric-free models, and B1IB2aB3I and B1CB2aB3I are suitable for positioning using non-combined models.
Conclusions BDS-3 has better positioning performance on a global scale, even better than GPS and Galileo in some frequency.