On Satellite-Borne GPS Data Quality and Reduced-Dynamic Precise Orbit Determination of HY-2C: A Case of Orbit Validation with Onboard DORIS Data

Abstract

Haiyang-2C (HY-2C) is a dynamic, marine-monitoring satellite that was launched by China and is equipped with an onboard dual-frequency GPS receiver named HY2_Receiver, which was independently developed in China. HY-2C was successfully launched on 21 September 2020. Its precise orbit is an important factor for scientific research applications, especially for marine altimetry missions. The performance of the HY2_Receiver is assessed based on indicators such as the multipath effect, ionospheric delay, cycle slip and data utilization, and assessments have suggested that the receiver can be used in precise orbit determination (POD) missions involving low-Earth-orbit (LEO) satellites. In this study, satellite-borne GPS data are used for POD with a reduced-dynamic (RD) method. Phase centre offset (PCO) and phase centre variation (PCV) models of the GPS antenna are established during POD, and their influence on the accuracy of orbit determination is analysed. After using the PCO and PCV models in POD, the root mean square (RMS) of the carrier-phase residuals is around 0.008 m and the orbit overlap validation accuracy in each direction reaches approximately 0.01 m. Compared with the precise science orbit (PSO) provided by the Centre National d’Etudes Spatiales (CNES), the RD orbit accuracy of HY-2C in the radial (R) direction reaches 0.01 m. The accuracy of satellite laser ranging (SLR) range validation is better than 0.03 m. Additionally, a new method is proposed to verify the accuracy of the RD orbit of HY-2C by using space-borne Doppler orbitography and radiopositioning integrated by satellite (DORIS) data directly. DORIS data are directly compared to the result calculated using the accurate coordinates of beacons and the RD orbit, and the results indicate that the external validation of HY-2C RD orbit has a range rate accuracy of within 0.0063 m/s.

Impact of Pseudo-Stochastic Pulse and Phase Center Variation on Precision Orbit Determination of Haiyang-2A from Experimental HY2 Receiver GPS Data

“…Due to the fact that the orbit solution strategy and data provided by CNES are different from those in this study, it can be used for external validation. The precise orbit provided by CNES is referenced to International Atomic Time (TAI), while the standard orbit time system calculated in this experiment is based on GPS time (GPST) [44]. Therefore, it is necessary to pretreat the PSO in advance to unify the time system of the RD orbit.…”

Inland Water Level Monitoring from Satellite Observations: A Scoping Review of Current Advances and Future Opportunities

“…HY-2B is equipped with dual-frequency altimeters (Ku and C bands), with a revisit period of 14 days in the early stage of the mission and 168 days at the end of the mission [89]. Also, the orbit revisit period of HY-2C is 10 days at the initial stage of the mission and it will become 400 days at the final stages [90]. In [71] is indicated that HY-2C has the highest temporal resolution among seven altimeters, with a temporal resolution of 7.5 days at one station, although it has the largest RMSE and therefore the lowest accuracy.…”

Refinement of GRACE‐FO Kinematic Orbit by Combining Least Squares Method and Orbital Dynamic Model

“…In the process of solving the POD of low-Earth orbit (LEO) satellites, researchers have made contributions in certain aspects [6][7][8][9][10][11][12][13][14][15][16][17][18]. Jäggi et al [7] used the least squares (LS) method to estimate GPS-based GRACE orbits, processing GPS data in the form of satellite-ground double-differenced (DD) carrier phase.…”