Investigation of the performance of real-time BDS-only precise point positioning using the IGS real-time service

With the development of China's BeiDou Navigation Satellite System (BDS) and the operation of the real-time service (RTS) of the International GNSS service, BDS real-time precise point positioning (RTPPP) has become possible. In this contribution, the RTS product CLK93 is employed for BDS RTPPP, and its quality for BDS orbit and clock corrections is first assessed by availability and accuracy over a period of 24days. Following this, the convergence time and positioning accuracy of BDS-only RTPPP are evaluated by performing a 24-day processing with ten stations from the multi-GNSS experiment (MGEX) network. Finally, a real-time kinematic test is conducted in an urban environment to further investigate the performance of BDS-only RTPPP. Experimental results show that the average availabilities of the CLK93 corrections are approximately 95% for the inclined geosynchronous satellite orbit (IGSO) satellites, 90% for the medium earth orbit (MEO) satellites and 65% for the geostationary earth orbit satellites. The mean accuracy of the real-time corrections, which is represented by the signal-in-space ranging error (SISRE)value, is 10cm for the IGSO and MEO satellites. Furthermore, the average positioning accuracies in the north, east and up components of the ten MGEX stations are approximately 1.7, 2.2 and 2.6cm, respectively, for the static mode and 10.3, 15.6 and 29.2cm, respectively, for the kinematic mode. In addition, the average time required to converge to a 20-cm accuracy in the three-dimensional component is approximately 100 and 136min for BDS-only RTPPP in the static and kinematic modes, respectively. In addition, the positioning accuracy of BDS-only RTPPP in the real-time kinematic test is 0.86, 0.92 and 1.68m in the east, north and up components, respectively, for the whole solutions during the test, which is obviously worse than that obtained by GPS-only RTPPP.