Fig. 4From: Performance evaluation of multi-GNSSs navigation in super synchronous transfer orbit and geostationary earth orbitThe number of visible satellites of the spacecraft in SSTO orbit under different combinations: a BDS; b GPS + Galileo + GLONASS; c GPS + Galileo + GLONASS + BDS (only MEO satellites); d GPS + Galileo + GLONASS + BDSBack to article page