Performance Evaluation of Three Atmospheric Density Models on HY-2A Precise Orbit Determination Using DORIS Range-Rate Data

Abstract

Abstract Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS) has become a matured and accurate space geodetic technique after more than two decades of development. DORIS’s main objective is precise orbit determination (POD) for the low earth orbit (LEO) satellite. For the POD of Haiyang-2A (HY-2A) satellite, a DORIS receiver was equipped on this mission. There are several nonconservative forces acting on a Haiyang-2A (HY-2A) satellite with an altitude of about 970 km. Out of the factors, the atmospheric drag is the most dominant and uncertain one during the process of POD with the dynamic method. The comparison between the computed orbits of HY-2A using DORIS range-rate data and the precise orbits computed by the Centre National d’Etudes Spatiales (CNES) has been performed, and the DORIS range-rate residuals have been analyzed in detail in normal period and frequent solar activity period. Tests demonstrated that the relative optimal atmospheric density model was the empirical MSIS-86 model for the HY-2A satellite. The root mean squares (RMSs) of orbit difference between the derived orbits using the MSIS-86 model and the CNES orbits were 0.0173 m in the radial direction and 0.0619 m in three dimensions. The RMS of the range-rate residual improved 0.024 mm/s during the frequent solar activity period with the atmospheric drag coefficient solved every three hours and then every six hours using the MSIS-86 model. This study will provide valuable references for POD and orbit prediction for the LEO satellites, especially for the other HY-2 series satellites of China.