Contact: Vladimir Suvorkin (suvorkin@ipa.nw.ru) Last updated: 09.02.2016 Technical description of solution 1. Purpose of solution: daily EOP 2. Analysis Center: Institute of Applied Astronomy (IAA), Russian Academy of Sciences 3. Short narrative description of solution: We process daily set of 24h RINEX-files of about 60-70 sites within IGS network. Processing strategy and reduction models mainly correspond to IERS Conventions (2010) and IGS recomendations. Solution method is based on segmented Least Squares for two groups of parameters (daily polynomial and 'every-epoch' with 30s sampling), no a'priori nor continuity constraints are applied. absolute antenna phase centers, wind-up corrections, and relativistic corrections are applied. 4. Estimated parameters: a. celestial frame: No b. terrestrial frame: No c. Earth orientation: Xp, Xp_rate, Yp, Yp_rate, LOD d. zenith troposphere: total delay as 12-degree Chebyshev polynomial with GMF Hydrostatic mapping function) e. troposphere gradient: horizontal north and east gradients as linear trends with Herring mapping function f. station clocks: independant for every 30s seconds aligned to GPS broadcast timescale g. satellite clock: independant for every 30s seconds aligned to GPS broadcast timescale h. satellite parameters: initial orbital parameters, 4-parameters of empirical SRP-model 5. Satellite motion: a. Geopotential model: IERS Conventions 2010 (Chapter 6) based on EGM2008 truncated to degree and order 12 with tidal corrections + Post- Newtonian relativistic corrections b. SRP model: no a'priori empirical model with 4 parameters c. Integration: Runge-Kutta method 6. Terrestrial reference frame: a. a priori station positions: IGb08 b. a priori station velocities: IGb08 velocity field c. reference epoch: 2005.0 d. station positions/velocities adjusted in solution: No 7. Earth orientation: a. a priori precession model: IAU2006 b. a priori nutation model: IAU2000A c. a priori short-period tidal variations in x, y, UT1: Diurnal and semidiurnal oceanic and lunisolar effects (Ch. Bizouard FORTRAN code) d. EOP estimation: daily Xp, Xp_rate, Yp, Yp_rate, LOD 8. A priori geophysical models: a. troposphere: Total zenith delay with GMF hydrostatic mapping function b. solid Earth tide: IERS Conventions (2010) c. ocean loading: IERS Conventions (2010) d. atmosphere loading: No 9. Data type: phase and code GNSS-measurements 10. Data preprocessing: Melbourne-Wubbena LC for cycle slip detection, outliers removing and satellite passes forming 11. Data weighting: No 12. Standard errors reported: Standard errors of least squares estimates 13 Software: IAA GNSS processing software 14. Other information: 15. Responsible person: Vladimir Suvorkin, suvorkin@ipa.nw.ru References: Suvorkin V., Kurdubov S., Gayazov I., GNSS Processing in Institute of Applied Astronomy RAS, Proceedings of the Journées 2014 "Systèmes de référence spatio-temporels", Z. Malkin and N. Capitaine (eds), Pulkovo observatory, 2015, ISBN 978-5-9651-0873-2 & ISBN 978-2-901057-70-3