Definition
Navigation systems that determine an aircraft's position, velocity, and time by receiving signals from a constellation of orbiting satellites. The receiver calculates its location by measuring the time it takes for signals to arrive from multiple satellites whose positions are precisely known. GPS is the most widely used example in aviation.
Plain English
A way of finding out exactly where the aircraft is by listening to signals from satellites in space. The receiver compares the timing of signals from several satellites and works out its own position from that.
Context Anchor
Seen in ADS-B discussions because ADS-B depends on a reliable position source, and that source is commonly a satellite-based navigation system.
Derivation
Satellite' comes from the Latin satelles, meaning 'attendant' or 'companion' — something that travels alongside a larger body. In navigation, the satellites are companions to Earth, orbiting it and serving as fixed reference points in the sky for receivers below.
Why Pilots Care
They supply the accurate position data required for ADS-B Out broadcasts and enable precise area navigation in instrument conditions.
Intuition Check
Do not read this as satellite weather, satellite radio, or ADS-B itself. Here, satellite navigation systems means the position-finding source that helps the aircraft know and report where it is.
Example Sentence 1
Most modern aircraft rely on satellite navigation systems for en route guidance and approach procedures.
Example Sentence 2
ADS-B equipment depends on satellite navigation systems to determine the aircraft's location before broadcasting it to controllers.