Definition
The network of fixed ground-based antennas that form part of the GPS control segment, used to send command and correction data from ground control stations up to the GPS satellites. They handle the uplink side of satellite management, including telemetry, tracking, and command signals.
Plain English
Antennas on the ground that talk up to the GPS satellites, sending them instructions and corrections from the people who run the system.
Context Anchor
Seen in GPS component descriptions, where the system is described as satellites in space, ground equipment on Earth, and receivers used by pilots and other users.
Derivation
Ground means the surface of the Earth. Antenna comes from an older word for a projecting pole and later came to mean a device that sends or receives radio signals. Together, ground antennas means radio signal equipment located on Earth rather than on an aircraft or satellite.
Why Pilots Care
They maintain the precision of GPS signals that pilots depend on for navigation and approach procedures.
Intuition Check
Do not assume ground antennas are the GPS antenna on the aircraft. In this context, they are fixed antennas on Earth that support and manage the GPS satellites.
Example Sentence 1
The GPS control segment uses ground antennas to upload navigation and clock corrections to each satellite as it passes overhead.
Example Sentence 2
Engineers monitor signals received by ground antennas to detect and correct any satellite clock or orbit errors.