GNSS Facts RNAV
The table of facts for the various GNSSGNSS —Global Navigation Satellite System system is, unfortunately, one of those things that has to be learned.
|NAVSTAR||GLONASSGLONASS —Global Orbiting Navigation Satellite System (Russia)||GALILEO|
|Number of Satellites||24 (3 Spare)||24 (3 Spare)||30 (6 Spare)|
|Number of Orbital Planes||6||3||3|
|Angle to Equator||55 degrees||64.8 degrees||56 degrees|
|Orbital Height (km)||20200||19100||23222|
|Orbital Height (nm)||10989||10313|
|Orbital Time (hrs)||12:00||11:15||14:00|
|Earth Reference||WGS84WGS84 —World Geodetic System 1984||PZ-90||ETRS89|
|L1 Frequency (MHz)||1575.42||1600||1164-1215|
|Time Reference||Atomic Clock||Atomic Clock||Rubidium/H2|
|Timing Basis||GPSGPS —Global Positioning System (USA)/UTCUTC —Co-ordinated Universal Time||GLONASSGLONASS —Global Orbiting Navigation Satellite System (Russia)/UTCUTC —Co-ordinated Universal Time||GALILEO/UTCUTC —Co-ordinated Universal Time|
Students have always reported when asked after exams that "pretty much all of it" came up on the exam. This is frustrating from both an instructor and student perspective as there is nothing inherently useful about any of the facts — even the frequencies are something you will never have to tune in yourself.
A good way to learn is to photograph the above table, save it as a tablet/mobile phone display, and then attempt to learn a little more each time you pick up the device. As ever with numbers, watch for the examiner giving incorrect units in the question or the answers (km instead of nm, GHz instead of MHz, etc.).