Space Vehicle Orbital Determination Performance Analysis Considering GNSS Side Lobe Signals

Global navigation satellite systems (GNSS), which were originally designed for terrestrial location service, are now developed for utility in space, which are called GNSS Space Service Volume (SSV). One major problem that SSV confronts is the poor satellite availability in high orbital vehicles when main beam signals are solely used. Recently, side lobe signals, the signals emitted sideways from transmitter antennas, have been proposed to improve the SSV performance. It is necessary to study the GNSS SSV with the presence of side lobe signals. In this paper, the system improvement owing to the side lobe signals in high orbital vehicles for specific missions is quantitatively evaluated. Different multi-constellation conditions and system setups are taken into account as factors. GPS and BDS III constellations are simulated, and the satellite availability and the maximum outage duration (MOD) are assessed in three scenarios, the GEO, HEO, and lunar trajectory, in different heights. The experimental results indicate that the side lobe signals can effectively improve satellite availability for space users, especially in the upper SSV. Moreover, it shows that the advantages of multi-constellation interoperability lie in improving signal availability and shortening the MOD.