Figure 2

Satellite visibility of Galileo, BeiDou, GLONASS and GPS at the four-system station GMSD (Japan) on September 3, 2013 (GPS Time).
Galileo, BeiDou, GLONASS and GPS satellites are shown by red, pink, blue and green lines, respectively.
Satellite visibility of Galileo, BeiDou, GLONASS and GPS at the four-system station GMSD (Japan) on September 3, 2013 (GPS Time).
Galileo, BeiDou, GLONASS and GPS satellites are shown by red, pink, blue and green lines, respectively.