IGS Workshop, June 02, Validation of GNSS Satellite Orbits C. Flohrer, G. Beutler, R. Dach, W. Gurtner, U. Hugentobler 1, S. Schaer, T. Springer 2 Astronomical Institute University of Bern 1 Institut for Astronomical and Physical Geodesy Technische Universität München 2 ESA/European Space Operations Center Darmstadt IGS Workshop, Miami Beach June 2, 2008

IGS Workshop, June 02, Inhalt Introduction SLR residuals Orbit overlaps 14-day peak

IGS Workshop, June 02, Known Problems 1/year 2/year 3/year 4/year 6/year 350·1/6 days Spectra of coordinate time series of IGS stationen draconitic GPS year, most probably due to orbit modeling deficiencies Ray, 2006

IGS Workshop, June 02, Known Problems

IGS Workshop, June 02, Known Problems

IGS Workshop, June 02, Known Problems

IGS Workshop, June 02, SLR Validation of GNSS Orbits G05 G06 σ 2.2 cm –3.5 cm –3.8 cm σ 2.7 cm

IGS Workshop, June 02, GLONASS 03 GLONASS 22 GLONASS 24 SLR Validation of GNSS Orbits

IGS Workshop, June 02, SatelliteStandard deviationOffsetNumber of Residuals G052.2 cm–3.5 cm11'400 G062.7 cm–3.8 cm10'900 R034.9 cm–1.0 cm17'600 R224.6 cm–0.4 cm21'000 R245.1 cm–0.3 cm12'600 R075.7 cm 0.5 cm 3'200 Results for CODE GNSS orbits SLR Validation of GNSS Orbits

IGS Workshop, June 02,  0 SLR Validation of GNSS Orbits

IGS Workshop, June 02, Residuals for CODE orbits of G05 and G06, ROCK a priori model SLR Validation of GNSS Orbits

IGS Workshop, June 02, Residuals for CODE orbits of G05 and G06, CODE a priori model SLR Validation of GNSS Orbits

IGS Workshop, June 02, Residuals for CODE GLONASS orbits SLR Validation of GNSS Orbits

IGS Workshop, June 02, Residuals for GFZ GPS orbits SLR Validation of GNSS Orbits

IGS Workshop, June 02, Residuals for IGS GPS orbits SLR Validation of GNSS Orbits

IGS Workshop, June 02, SLR Validation of GNSS Orbits Plane BLOCK II BLOCK IIR

IGS Workshop, June 02, Orbit Overlaps, 1-Day CODE Orbits radial alongtrack crosstrack G28

IGS Workshop, June 02, Orbit Overlaps, 1-Day CODE Orbits 40 cm Plane 2 Plane 3 Plane 1 β max = 78° β max = 76° β max = 70°

IGS Workshop, June 02, Orbit Overlaps, 1-Day CODE Orbits Plane 4 Plane 6 Plane 5 β max = 61° β max = 51° β max = 40°

IGS Workshop, June 02, Orbit Overlaps, 1-Day CODE Orbits Plane 2 Plane 3 Plane 1 β max = 78° β max = 76° β max = 70°

IGS Workshop, June 02, Orbit Overlaps, 1-Day CODE Orbits Plane 4 Plane 6 Plane 5 β max = 61° β max = 51° β max = 40°

IGS Workshop, June 02, Orbit Overlaps, Amplitude Spectra

IGS Workshop, June 02, Mean Power Spectrum, 14-Day Line

IGS Workshop, June 02, Mean Power Spectrum, 14-Day Line

IGS Workshop, June 02, Mean Power Spectrum, 14-Day Line

IGS Workshop, June 02, Mean Power Spectrum, 14-Day Line

IGS Workshop, June 02, Mean Power Spectrum, 14-Day Line

IGS Workshop, June 02, Mean Power Spectrum, 14-Day Line

IGS Workshop, June 02, Mean Power Spectrum, 14-Day Line

IGS Workshop, June 02, Mean Power Spectrum, 14-Day Line

IGS Workshop, June 02, Mean Power Spectrum, 14-Day Line

IGS Workshop, June 02, Mean Power Spectrum, 14-Day Line

IGS Workshop, June 02, Phase Spectrum, Plane-specific

IGS Workshop, June 02, Phase Spectrum, Plane-specific

IGS Workshop, June 02, Phase Spectrum, Plane-specific

IGS Workshop, June 02, Phase Spectrum, Plane-specific

IGS Workshop, June 02, Phase Spectrum, Plane-specific

IGS Workshop, June 02, Phase Spectrum, Plane-specific

IGS Workshop, June 02, Phase Spectrum, Mean for Planes

IGS Workshop, June 02, Power Spectra of Helmert Parameters

IGS Workshop, June 02, Power Spectra of Helmert Parameters

IGS Workshop, June 02, Power Spectra of Helmert Parameters

IGS Workshop, June 02, Power Spectra of Helmert Parameters

IGS Workshop, June 02, Power Spectra of Helmert Parameters

IGS Workshop, June 02, Power Spectra of Helmert Parameters

IGS Workshop, June 02, CODE 1d Solution, 24h Pole Estimate

IGS Workshop, June 02, CODE 1d Solution, 2h Pole Estimate

IGS Workshop, June 02, Orbit modeling problems affect the entire solution Orbit periods are found in station positions and geocenter motion SLR Residuals show a characteristic pattern Patterns in orbit overlap time series seem not to be influenced by the a priori orbit model Patterns depend on the maximum elevation of the Sun above the orbital plane which indicates problems with the estimated empirical orbit parameters Prominent peak at 14-days In alongtrack and crosstrack directions In phase for all satellites Period seems to be related to tidal corrections in the system orientation Probably due to the used subdaily pole model Conclusions