MEO and HEO satellites orbit determination based on GNSS onboard receiver

Abstract

The method of Middle Earth Orbit (MEO) and High Earth Orbit (HEO) satellites orbit determination based on Global Navigation Satellite System (GNSS) onboard receiver has several disadvantages such as less navigation satellites signal, poor geometrical coverage, and weaker navigation signal. Using the weak signal receiver to get the side-lobe signal is a good way. But as a result of weak receiving power and poor C/N0 (Carrier-to-Noise ratio) of the side-lobe signal, the observation noise was increased considerably, and the stochastic models of the main beam and side-lobe signal are different. Based on the Chinese COMPASS navigation system, this thesis analyses the restrictions of the aspects of GNSS signal geometries visible conditions. The simulation noise sigma model is based on the C/N0 of the observation as an exponential function. The orbits were determined by combining the main beam and side-lobe signal. The beam angle of main beam and side-lobe is 0°-21.3° and 21.3°-45°, respectively, navigation signal transit power is 26.8 W (Watt), receiving C/N0 threshold is 25 dB Hz and the system error of inter-satellite link is 20 cm. The precision of orbit determination of MEO is better than 0.3 m, and the GEO is 1.0 m. Lastly, navigation satellites integrated orbit determination was carried out using ground observations from six regional stations in China and inter-satellite link observations which is simulated by installing onboard receivers on each of the navigation satellites. © 2012 Springer-Verlag.