Preliminary Evaluation of Performance of BeiDou Satellitebased Augmentation System

Abstract:

BeiDou navigation satellite system (BDS) integrates legacy PNT and authorized differential service, where differential service is provided by the satellitebased augmentation system (SBAS). The latest progress of the BDS SBAS development were introduced and the performance of pseudorange based and carrier phase based user differential positioning was evaluated. Observations of 10 stations in Chinese mainland were used. The results show that the coordinate accuracy of the pseudorange differential positioning (SBAS SPP) reaches 0.4 m, 0.3 m and 0.8 m in the North, East and Up directions respectively, which shows an improvement of 53% over the legacy SPP. For the evaluation of carrier phase based positioning, kinematic precise point positioing (SBAS PPP) was performed and compared to the kinematic PPP results based on post processing precise satellite orbits and clocks (POST PPP). The results show that the SBAS PPP kinematic coordinate estimates converge to 1 meter in 7 mins on average and the coordinate accuracy reaches 0.1 meter in horizontal and 0.2 meter in vertical component after convergence. Compared to the results of POST PPP, SBAS PPP shows better accuracy and shorter converge time, which indicates that the accuracy of BDS satellite orbits has been increased and clocks still have to be improved.

Key words:BeiDou satellite navigation system; satellitebased augmentation system; widearea differential information; realtime kinematic PPP