PhD ThesisPrecise Point Positioning (PPP) provides GNSS navigation using a stand-alone receiver with no base station. As a technique PPP suffers from long convergence times
and quality degradation during periods of poo satellite visibility or geometry. Many
applications require reliable realtime centimetre level positioning with worldwide
coverage, and a short initialisation time. To achieve these goals, this thesis considers
the use of GLONASS in conjunction with GPS in kinematic PPP. This increases
the number of satellites visible to the receiver, improving the geometry of the visible
satellite constellation.
To assess the impact of using GLONASS with PPP, it was necessary to build a real
time mode PPP program. pppncl was constructed using a combination of Fortran
and Python to be capable of processing GNSS observations with precise satellite
ephemeris data in the standardised RINEX and SP3 formats respectively. pppncl
was validated in GPS mode using both staticsites and kinematic datasets.In GPS
only mode,one sigma accuracy of 6.4mm and 13mm in the horizontal and vertical
respectively for 24h static positioning was seen. Kinematic horizontal and vertical
accuracies of 21mm and 33mm were demonstrated.
pppncl was extended to assess the impact of using GLONASS observations in addi-
tion to GPS instatic and kinematic PPP. Using ESA and Veripos Apex G2 satel-
lite orbit and clock products,the average time until 10cm 1D static accuracy was
achieved, over arange of globally distributed sites, was seen to reduce by up to
47%. Kinematic positioning was tested for different modes of transport using real
world datasets. GPS/GLONAS SPPP reduced the convergence time to decimetre
accuracy by up to a factor of three. Positioning was seen to be more robust in comparison to GPS only PPP, primarily due to cycle slips not being present on both
satellite systems on the occasions when they occurred,and the reduced impact of
undetected outliersEngineering and Physical Sciences Research Council, Verip os/Subsea
