5:15 PM - 6:45 PM
[SGD01-P12] Consistency between multi-GNSS PPP solutions and F5 solutions and among multi-GNSS PPP solutions from different analysis methods
Keywords:Precise Point Positioning, PPP, GNSS
It is known that between the PPP daily solution of GEONET stations using GPS and GLONASS data has a vertical bias of about -2 cm (positive upward. The same below) with respect to the F5 solution of the GEONET routine analysis. To investigate the reason, the following four comparisons were made for daily multi-GNSS PPP static solutions with different analysis methods, using one month data from all GEONET stations from August 1st to 31st, 2021.
(1) F5 solution and PPP GPS solution using the IGS final ephemeris to compare different analysis methods.
(2) PPP GPS solution using the IGS final ephemeris and PPP GPS solution using the post-processing ephemeris estimated by GSI to evaluate contributions of ephemeris
(3) PPP GPS solution and PPP GPS+GLONASS solution both using the post-processing ephemeris estimated by GSI to evaluate contributions of satellite system used in the analysis.
(4) PPP GPS+GLONASS solution in which the same phase center characteristic model are applied to both GPS and GLONASS, and PPP GPS+GLONASS solution in which the phase center characteristic model of GLONASS was estimated separately from GPS, to evaluate contribution of phase center characteristic model
The tentative results show:
(1) Effect of different analysis methods: The PPP GPS solution using the IGS ephemeris has a bias of -7mm~15mm with respect to the F5 solution depending on the antenna and mount type.
(2) Effect of different ephemeris: The PPP GPS solution using the post-processing ephemeris estimated by GSI had a constant bias of -20mm to -15mm with respect to the PPP GPS solution using the IGS ephemeris.
On the other hand, in the following cases
(3) Influence of the difference of satellite systems used in the analysis: The bias of the PPP GPS+GLONASS solution with respect to the PPP GPS solution. (For both solutions, the same post-processing ephemeris estimated by GSI was used in the analysis).
and
(4) Effect of differences in phase center characteristic models: The bias of the PPP GPS+GLONASS solution in which the phase center characteristic model of GLONASS was estimated separately from GPS, with respect to the PPP GPS+GLONASS solution in which the same phase center characteristic model are applied to both GPS and GLONASS
the biases are relatively small, about +/-5mm in both cases. This result implies that most of the bias between the F5 and PPP solutions can be attributed to differences in analysis methods and ephemeris.
(1) F5 solution and PPP GPS solution using the IGS final ephemeris to compare different analysis methods.
(2) PPP GPS solution using the IGS final ephemeris and PPP GPS solution using the post-processing ephemeris estimated by GSI to evaluate contributions of ephemeris
(3) PPP GPS solution and PPP GPS+GLONASS solution both using the post-processing ephemeris estimated by GSI to evaluate contributions of satellite system used in the analysis.
(4) PPP GPS+GLONASS solution in which the same phase center characteristic model are applied to both GPS and GLONASS, and PPP GPS+GLONASS solution in which the phase center characteristic model of GLONASS was estimated separately from GPS, to evaluate contribution of phase center characteristic model
The tentative results show:
(1) Effect of different analysis methods: The PPP GPS solution using the IGS ephemeris has a bias of -7mm~15mm with respect to the F5 solution depending on the antenna and mount type.
(2) Effect of different ephemeris: The PPP GPS solution using the post-processing ephemeris estimated by GSI had a constant bias of -20mm to -15mm with respect to the PPP GPS solution using the IGS ephemeris.
On the other hand, in the following cases
(3) Influence of the difference of satellite systems used in the analysis: The bias of the PPP GPS+GLONASS solution with respect to the PPP GPS solution. (For both solutions, the same post-processing ephemeris estimated by GSI was used in the analysis).
and
(4) Effect of differences in phase center characteristic models: The bias of the PPP GPS+GLONASS solution in which the phase center characteristic model of GLONASS was estimated separately from GPS, with respect to the PPP GPS+GLONASS solution in which the same phase center characteristic model are applied to both GPS and GLONASS
the biases are relatively small, about +/-5mm in both cases. This result implies that most of the bias between the F5 and PPP solutions can be attributed to differences in analysis methods and ephemeris.