Galileo is the European GNSS (Global Navigation Satellite System) solution, operated by the European Space Agency.
Galileo was released in the year 2016 and is currently operated by the European GNSS Agency (GSA), which has its headquarters in Prague, Czech Republic, supplemented by two ground control centres in Italy and Germany; the regions of Fucino & Oberpfaffenhofen respectively.
GPS and Galileo
Galileo was released with the intention to be superior to other GNSS systems; to provide vertical & horizontal position measurements within 1-metre precision, with better positioning services at latitudes that were higher.
Another reason that it was created was to be an independent system, which did not need to rely on Americas GPS, or Russia’s Glonass.
Configuration
Space
Galileo was scheduled to have 15 operational satellites in 2015, with full system operation of 30 as of 2020.
- 30 Medium Earth Orbit (MEO) satellite (24 in full service and 6 spares)
- Orbital altitude of 23,222 km
- 3 orbital planes of 56.0° inclination
- Each ascending nodes separated by 120.0° longitude
Ground
The ground system controls signal accuracy and the satellites orbital route. It is comprised of
- Satellite & Mission Control
- Ground Control Center #1- Oberpfaffenhofen, Germany
- Ground Control Center #2 – Fucino, Italy
- Worldwide distributed reference sensor stations (GSS)
- Collect and forward Galileo SIS measurements and data to the GCCs in real time.
- Telemetry, Tracking & Control Stations (TT&C)
- Locations
Kiruna, Kourou, Nouméa, Sainte-Marie, Réunion, Redu and Papeete
- Locations
- Ten mission data uplink stations (ULS), two per site
- Locations
Svalbard, Kourou, Papeete, Sainte-Marie, Réunion and Nouméa
- Locations
- Service Center
- Location
Madrid
- Location
Galileo Services
The mission & services for Galileo were determined during the initial phases of the project in consultation with communities of users and the Member States.
The services that are provided by the full operational Galileo GNSS service are to be as follows
Open Service (OS):
Open Service is freely accessible to the mass market, intended for use with vehicles navigation and mobile telephone services that are location-based.
This service is free to the end user, and it provides and synchronization and positioning data intended for applications that utilize high-volume satellite radio navigation.
High Accuracy Service (HAS):
HAS compliments Open Service by providing additional signal & value in separate frequency bands. These additional signals can be encrypted to control who has access to this service.
Public Regulated Service (PRS):
The Public Regulated Service (PRS) is only available to government authorized users. It is restricted to these users as it services sensitive applications which require a high levels of security clearance.
PRS is designed to be more robust by employing encryption and utilizing anti-jamming mechanisms, as well as error checking and monitoring for the early & ongoing detection of issues.
Primarily, PRS is used for infrastructure which requires security; energy, finance, telecommunications, government.
Search and Rescue Service (SAR)
The Galileo Search & Rescue (SAR) service is designed to forward signals of distress emitted from emergency beacons, as well as relay messages back to them.