1 Lopatin V.P.
2 Murzabekov M.M.
3 Bobrov D.S.

FSUE «All-Russian Scientific Research Institute of Physical-Technical and Radiotechnical Measurements» (FSUE «VNIIFTRI»)

The method for determining geoid elevations, based on the use of GNSS signals reflected from water surface, is called bistatic one. Its features are small dimensions and weight of the necessary on-board equipment, and that enables mounting them on a nano-satellite, as well as simultaneously determining several dozen geoid height profiles. It corresponds to the number of visible navigation satellites from among GLONASS, GPS, Galileo, BeiDou. Several space projects using the technology under description were implemented abroad, their analysis has shown the possibility of determining geoid heights with an error of 10–20 cm, as well as sea ice thickness. The authors provide a review of some similar projects, an assessment of the simultaneously determined number of geoid height profiles, and calculation of its elevations and deflection of vertical along a single profile based on primary measurements from the project of CYGNSS. To compensate for various interfering parameters when calculating geoid elevations, the following models were used: of ocean tide EOT20; of mean global sea level DNSC08; the ionospheric CODG one; the climate parameters ERA5. Based on the results of comparison with data from the EGM2008 geopotential model, standard deviations of the difference were obtained for geoid elevations of 15,9 cm and for a deflection of vertical of 1′′
The research was supported by the Russian Science Foundation grant No. 23-67-10007
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Lopatin V.P., 
Murzabekov M.M., 
Bobrov D.S., 
(2024) Results of determining the geoid height profile and vertical line deviation using GNSS signals reflected from water surface. Geodesy and cartography = Geodezia i Kartografia, 85(2), pp. 21-30. (In Russian). DOI: 10.22389/0016-7126-2024-1004-2-21-30