Real-time
precise point positioning (PPP) is possible through the use of real-time
precise satellite orbit and clock corrections, which are available through a
number of organizations including the International GNSS Service (IGS) real-time service (IGS-RTS).
Unfortunately, IGS-RTS is only available for the GPS and GLONASS
constellations. In 2018, a new real-time service, NAVCAST, which provides
real-time precise orbit and clock corrections for the GPS and Galileo
constellations, was
launched. In this research, the potential performance of real-time PPP which
makes use of NAVCAST real-time corrections is analyzed using various static and
kinematic datasets. In the static dataset, 24 hours of observations from eight
IGS stations in Canada over three different days were utilized. The static
results show that the contribution of Galileo satellites can improve the
positioning accuracy, with 30%, 34%, and 31% in east, north, and up directions
compared to the GPS-only counterparts. In addition, centimeter-level
positioning accuracy in the horizontal direction and decimeter-level
positioning accuracy in the vertical direction can be achieved by adding
Galileo observations. In the kinematic dataset, a real vehicular test was
conducted in urban and suburban combined areas. The real-time kinematic
GPS/Galileo PPP solutions demonstrate an improvement of about 53%, 45%, and 70%
in east, north, and up directions compared to the GPS-only counterparts. It is
shown that the real-time GPS/Galileo PPP can achieve a sub-decimeter horizontal
positioning accuracy and about meter-level vertical positioning accuracy
through the use of NAVCAST real-time corrections.
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