Improving solar radiation pressure modeling for GLONASS satellites

Abstract

The Russian Global Navigation Satellite System (GLONASS) satellites have a stretched body shape and take a specific attitude mode inside the eclipse. Based on previous studies, the new Empirical CODE orbit model (ECOM2) performs better than the classical ECOM model if a satellite has elongated shape or does not maintain yaw-steering mode, and the use of an a priori box-wing (BW) model improves the orbits significantly when employing the ECOM model. However, we find that the ECOM model performs better than the ECOM2 model for GLONASS satellites outside eclipse seasons, while it performs two times worse in eclipse seasons. The use of the conventional box-wing model results in very little improvement. By assessing the ECOM Y 0 estimates, we conclude that there are potential radiators on the −x surface of GLONASS satellites causing orbit perturbations also inside the eclipse. The higher-order Fourier terms of the ECOM2 model can compensate for such effects better than the ECOM model. Based on this finding, we first confirm that GLONASS-K satellites take a similar attitude mode as GLONASS-M satellites inside the eclipse. Then, we adjust optical parameters of GLONASS satellites as part of precise orbit determination (POD) considering the potential radiator and thermal radiation effects. Finally, the adjusted parameters are introduced into a new box-wing model and jointly used with the ECOM and ECOM2 model, respectively. Results show that the amplitude and the dependency of the empirical parameters on the β angle are greatly reduced for both ECOM and ECOM2 models. Rather than the conventional box-wing model, the new box-wing model reduces the orbit misclosure between two consecutive arcs for both GLONASS-M and GLONASS-K satellites. In particular, the improvement in GLONASS-M satellites is more than 30% for the ECOM model during eclipse seasons. Further evaluation from 24-h predicted orbits demonstrates that the improvement during eclipse seasons is mainly in along-and cross-track directions. Finally, we validate GLONASS satellite orbits using Satellite Laser Ranging (SLR) observations. The use of the new box-wing model reduces the spurious pattern of the SLR residuals as a function of β and u significantly, and the linear dependency of the SLR residuals on the elongation drops from as large as −0.760 mm/deg to almost zero for both ECOM and ECOM2 models. In general, GLONASS-M satellites benefit more from the new a priori box-wing model and the BW+ECOM model results in the best SLR residuals, with an improvement of about 50% and 20%, respectively, for the mean and standard deviation (STD) values with respect to the orbit products without a priori model.

Precise orbit determination for BDS satellites

“…Recently, Sidorov et al (2020) identified that TR force due to the emitted heat from the thermal radiator caused by the onboard atomic clock generated the orbit errors in eclipse seasons for Galileo satellites. Moreover, based on the analysis of Y 0 of ECOM1 model, the potential radiators on the −X surface were identified for GLONASS satellites (Duan et al, 2020). Wang et al (2019c) also introduced a periodic acceleration along +X direction to compensate TRP for BDS satellites, particularly for C13.…”

Enhanced solar radiation pressure model for GPS satellites considering various physical effects

“…Optical parameters + and are adjusted in + X and ± Z surfaces for each satellite (Duan et al 2019b). The solar panel parameter is estimated to compensate for the thermal radiation performed on solar panels (Duan et al 2020). A rotation lag of solar panels is estimated for each satellite (Rodriguez-Solano et al 2012a).…”

“…Then, we show the impact of all the discussed physical effects on SRP. Third, we adjust all the box-wing parameters, including additional physical parameters, such as yaw bias, radiator emission and thermal radiation (Duan et al 2020(Duan et al , 2019bRodriguez-Solano et al 2012a). In addition, the GSPM parameters are determined as well by using the same GPS measurements.…”

Comparisons of CODE and CNES/CLS GPS satellite bias products and applications in Sentinel-3 satellite precise orbit determination

“…Optical and infrared properties of each Sentinel-3 satellite surface are given by Montenbruck et al (2018). With this detailed information, solar radiation pressure (SRP) can be described by a box-wing macro model, as shown for one plane (Duan et al 2020), where acc represents the acceleration, A the surface area, M the total mass of the satellite, S 0 the solar flux, c the vacuum velocity of light, the thermal re-radiation factor (0 for solar panels and 1 for satellite body surfaces in this contribution), , , the fractions of absorbed, diffusely scattered, and specularly reflected photons. Furthermore, D denotes the Sun direction, N the surface normal vector, and the angle between both vectors.…”