GNSS Constellation Comparison Flashcards
To know the difference between NAVSTAR, GLONASS and GALILEO
Number of satellites in Galileo?
30
Number of Satellites in GLONASS?
24
Number of satellites in NAVSTAR?
21 operational + 3 spare
Number of orbits and how many satellites in each orbit, NAVSTAR?
6 orbits - 4 satellites in each orbit
Number of orbits and how many satellites in each, GLONASS?
3 orbits - 8 satellites in each orbit
Number of orbits and how many satellites in each, Galileo?
3 orbits - 9 satellites and 1 spare in each orbit
Orbit inclination with equator in NAVSTAR?
55 degrees
Orbit inclination from equator in GLONASS?
64.8 degrees
Orbit inclination from equator in Galileo?
56 degrees
Height of GLONASS orbits?
19,100km
Height of NAVSTAR orbits?
20,200km
Height of Galileo orbits?
23,222km
Time for NAVSTAR orbit?
12hrs (11h58m)
Time for GLONASS orbit?
11h15m
Time for Galileo orbit?
14h
What’s the Earth reference used in GLONASS?
PZ-90
What’s the Earth reference used in NAVSTAR?
WGS-84
What’s the Earth reference used in Galileo
EGTS-89
What time does Galileo work on?
GMT
What time does GLONASS work on?
UTC/ZULU
What time does NAVSTAR work on?
GPS time
NAVSTAR Link frequencies?
L1 - 1575.42MHz
L2 - 1227.6MHz
GLONASS link frequencies?
L1 - 1.6GHz
L2 - 1.2GHz
Galileo Link frequencies?
1164-1215MHz
1260-1300MHz
1559-1591MHz (shared with GPS on a non-interference basis)
How many atomic clocks in Galileo?
2 - One rubidium frequency standard clock and one passive hydrogen maser clock
How many atomic clocks in NAVSTAR?
Three or Four
