资源环境科技发展态势分析平台

All satellites of new Global Navigation Satellite Systems (GNSS) are equipped with laser retroreflectors dedicated to Satellite Laser Ranging (SLR). This paper demonstrates the contribution of SLR tracking of multi-GNSS constellations to the improved SLR-derived reference frame and scientific products. We show a solution strategy with estimating satellite orbits, SLR station coordinates, geocenter coordinates, and Earth rotation parameters using SLR observations to 2 Laser Geodynamics Satellites (LAGEOS) and 55 GNSS satellites: 1 GPS, 31 Globalnaya Navigatsionnaya Sputnikovaya Sistema, 18 Galileo, 3 BeiDou Inclined Geosynchronous Orbit, 1 BeiDou Medium Earth Orbit, and 1 Quasi-Zenith Satellite System satellite for the period 2014.0-2017.4. Due to a substantial number of GNSS observations, the number of weekly solutions for some SLR stations, for example, Arkhyz, Komsomolsk, Altay, and Brasilia, is larger up to 41% in the combined LAGEOS+GNSS solution when compared to the LAGEOS-only solution. The SLR observations to GNSS can transfer the orientation of the reference frame from GNSS to SLR solutions. As a result, the SLR-derived pole coordinates and length-of-day estimates become more consistent with GNSS microwave-based results. The root-mean-square errors of length-of-day are reduced from 122.5 mu s/d to 43.0 mu s/d, whereas mean offsets are reduced from -81.6 mu s/d to 0.5 mu s/d in LAGEOS only and in the combined LAGEOS+GNSS solutions, respectively.

Plain Language Summary The advent of new Global Navigation Satellite Systems (GNSS) equipped with laser retroreflector arrays opened new opportunities for geodetic and geophysical studies. Satellite Laser Ranging (SLR) with millimeter accuracy to Galileo, Globalnaya Navigatsionnaya Sputnikovaya Sistema, BeiDou, and Quasi-Zenith Satellite System allows not only for the orbit quality assessment but also for deriving global parameters, such as Earth rotation parameters, including polar motion and length-of-day excess, station, and geocenter coordinates, as well as the global scale. The laser stations support the multi-GNSS constellations on a regular basis and in the framework of special campaigns dedicated to selected GNSS systems. In the beginning of 2017, the number of SLR observations to GNSS exceeded the number of SLR observations collected to geodetic satellites, despite the fact that the tracking high-orbiting GNSS imposes a great challenge for the laser stations. Using the GNSS satellites introduces great opportunities toward the improvement of the SLR-derived reference frame, SLR-derived geodynamic parameters, and may substantially contribute to the enhancement of the consistency between both space geodetic techniques.