A ground station, earth station, or earth terminal is defined as a terrestrial radio station designed for extra planetary telecommunication with spacecraft. It can be thought of as a constituting part of the ground segment of the spacecraft system.
For the SatNOGS project a ground station is a combination of hardware and software used to receive satellite signals.
Types of ground stations
Ground can be grouped into ones with movable antennas and ones with static antennas.
Ground stations with movable antennas point one or more directional antennas towards the satellite and tracks them as they cross the sky. Either a commercial or SatNOGS type rotator can be used to move the antenna(s). More information can be found on the rotators page.
SatNOGS also makes provision for static antenna ground stations. These are typically simpler and rely on no moving parts but require an antenna that has a broad view of the sky. Typical installations tend to work well with higher passes but will struggle to achieve successful observations when satellites pass lower to the horizon.
A ground station also needs a receiver. The RTL-SDR dongle is typically used as a receiver, and the Raspberry Pi is the integration between the ground station and SatNOGS network. Further information can be found in the receivers page
A receiver is connected to an antenna or antennas. The type of antenna used depends on the ground station. Different satellites will have different uplinks and downlinks and the choice of antenna will affect the observation. See the Antennas page for typical ground station set ups.
This wiki will focus on the SatNOGS ground station but it is worth noting that commercial rotators and commercial receivers have been used in some instances.