Real-Time Kinematic (RTK) Global Positioning System (GPS) carrier phase-based precise positioning has been widely using in geodesy and surveying applications, and other high accuracy positioning and navigation applications in the last two decades. More Global Navigation Satellite Systems (GNSS) are being developed and it is usually expected that combining GNSS will have a positive impact on positioning accuracy. This paper describes a case study carried out at Ningbo in China on the impact of multi-GNSS on RTK single epoch solutions. Both GPS and GLONASS are fully operational now. Moreover, the Quasi-Zenith Satellite System (QZSS) can be observed at Ningbo. Currently, only one QZSS satellite “MICHIBIKI” is operational. This paper carries out an early assessment of the impact of QZSS on GPS and GLONASS single-epoch high precision positioning (i.e., single-epoch positioning accuracy assessment) and investigates the multipath errors in the GPS, GLONASS and QZSS multi-frequency data.
