view of planet

System and programme




What is Galileo?

Galileo is the European Union's Global Satellite Navigation System (GNSS). Like the other global systems, Galileo provides radio signals for position, navigation and timing purposes. When completed, Galileo will offer the following services: Open Service, Public Regulated Service, Search and Rescue Service, High Accuracy Service, and Commercial Authentication Service. Click here for more information.

What is Galileo?


What does Galileo consist of?

The Galileo system is composed of three segments:

Space segment: The Galileo Space Segment consists of a constellation of satellites transmitting navigation signals providing user access to the Galileo services. The baseline constellation configuration is defined as 24/3/1 Walker constellation. 24 nominal Medium Earth Orbit satellites are arranged in 3 orbital planes.

Ground segment: The Galileo Ground Segment includes both the Ground Control Segment (GCS) and the Ground Mission Segment (GMS) and it encompasses the following infrastructures:
• Two Galileo Control Centres (GCC)
• A worldwide network of Galileo Sensor Stations (GSS).
• A worldwide network of Galileo Uplink Stations (ULS).
• A worldwide network of Telemetry, Tracking & Control stations (TTC stations).

User segment: Different GNSS receivers and devices, which receive the Galileo Signal In Space (SiS).

Click here for more information.

European GNSS Service Centre (GSC)


Why does Europe need Galileo?

Space is big business. The space sector is worth between €46-54 billion to the EU economy and provides over 230,000 jobs in the EU. What’s more, the global GNSS market is expected to grow from 5.8 billion devices in 2017 to an estimated 8 billion by 2020, with 7.5 billion apps using GNSS. Thanks to this growth, the GNSS downstream market is expected to generate over EUR 70 billion in revenue annually, which more than doubles when revenue from added-value services is included.

With its own GNSS system in Galileo, Europe is at the forefront of these developments. The European research and development and industrial sectors are able to leverage Galileo’s increased accuracy in countless products and services, creating added value for the European economy and improving the lives of European citizens.

It is also important to remember that, unlike other global satellite navigation systems, Galileo is a civilian system – it was conceived with service provision to end users at its core. This is an important distinction, especially as our dependence on GNSS continues to increase.


Who is involved in Galileo?

Galileo is a joint initiative of the European Commission, the European GNSS Agency and the European Space Agency.

The Galileo programme is owned by the European Union (EU).

The European Commission has overall responsibility for the programme, managing and overseeing the implementation of all activities on behalf of the EU.

Galileo's design, deployment, evolutions of the system and the technical development of infrastructure are entrusted to the European Space Agency (ESA).

The Commission has delegated the operational management of the programme to the GSA, which oversees how Galileo infrastructure is used and ensures that Galileo services are delivered as planned and without interruption.


What is the socio-economic impact of Galileo?

The benefits of Galileo can be measured by their socio-economic impact on users, society and the environment.

Users will benefit from more reliable and accurate positioning, aiding their navigation, especially in cities and built-up areas. Features like the Galileo Search and Rescue service and integration into the eCall system will reduce emergency service response time in the case of distress or accidents.

Also, Galileo's accurate timing will help make synchronisation of banking and financial transactions more resilient as well as those used in telecommunication and energy distribution networks that power the World economy.

Use of satellite navigation has helped drive world economic growth, particularly in high-tech industries, and experts predict that the global satellite navigation market will itself grow by more than 8% up until 2019. The additional resiliency provided by Galileo as the third global system, after GPS and GLONASS, is expected to enable a range of new applications and services that will benefit from increased positioning reliability and further drive economic growth in Europe and beyond.

The European GNSS Agency (GSA) has conducted additional assessments that show significant economic and environmental benefits from Galileo and GNSS use in the decade to come.

Who is using Galileo today?


What is the added value of Galileo with respect to other GNSS?

Europe is the only region worldwide developing a global civil-based GNSS initiative. Galileo programme stands alone as the world’s unique option for GNSS under civilian control. This is an important differentiator with regard to other GNSS systems, especially relevant when considering that the world’s dependence on GNSS is continuously increasing.

With Galileo constellation available, there are more GNSS satellites usable, meaning more accurate and reliable positioning and timing synchronization that can be globally achieved by the end users. This is especially relevant in higher latitudes where Galileo offers better coverage than other GNSS systems.

In addition, Galileo offers other added value services devoted to improving the performances at user level. To be remarked, Galileo allows:
• Positioning accuracy down to decimetre level.
• Robust positioning through the authentication of the navigation data.
• Resistance to interference (jamming and spoofing) and high resilience.
• Introduction of a return link for Search and Rescue operations.

Galileo Search and Rescue (SAR)


When will Galileo reach the Final Operational Capability (FOC)?

Galileo performance will gradually be improved and new services will be introduced as further spacecraft are launched.

The full constellation is expected to be available by 2020. When the full constellation is in orbit and usable, the Full Operational Capability stage will be declared.


Do I have to pay for Galileo services?

The Galileo Services are free of charge and once the system becomes fully operational the Open Service and Search and Rescue Service will continue to be provided on a free-of-charge basis. The future High Accuracy Service (HAS) will also be offered free of charge.

Commercial Authentication Service (CAS) may be offered on a commercial basis, but this has still to be defined.

Is Galileo free?


Who operates the Galileo system?

While the European Commission is ultimately responsible for the Galileo programme, the European GNSS Agency (GSA) is responsible for deploying the system and providing technical support for operational tasks, in addition to service provision and market development.

In this way, the GSA serves as the link between the satellites in space and the end user.


When will I be able to use Galileo?

If you have a Galileo-enabled device, then you are already benefitting from Galileo’s added accuracy. Since Initial Services were launched in 2016, users around the world with Galileo enabled devices are being guided with positioning, navigation and timing information provided by Galileo.

Click here to find out if your device is Galileo-enabled.


How many satellites will Galileo have?

Once the Galileo constellation reaches Full Operational Capability (FOC) it will consist of 30 satellites. The constellation will contain 24 operational satellites and six spares. From most locations, six to eight satellites will always be visible, allowing positions and timing to be determined very accurately to within a few centimetres. Interoperability with other GNSS increases the reliability of Galileo services.

The next launches are planned from late 2020 onwards. In a first phase, this will re-enforce the constellation with the deployment of spare satellites. After this, subsequent launches will be used for constellation replenishment purposes.


What is multi-constellation capacity?

Galileo is interoperable with other Global Navigation Satellite Systems (GNSS) such as GPS, Russia’s GLONASS and China’s BeiDou. Receivers with multi-constellation capacity are able to combine signals from different constellations to provide greater positioning accuracy.

To further increase the level of Galileo integration, the GSA works directly with chipset and receiver manufacturers through technology workshops, sharing Galileo updates, co-marketing efforts, and dedicated funding for receiver development projects and studies.

To learn more about multi-constellation, watch this video:


To find out if your receiver is Galileo-enabled, click here

How is Galileo performing?

Galileo’s performance has been excellent! Since the launch of Initial Services, the measured Galileo Open Service and Search and Rescue Service performance figures have comfortably exceeded the Minimum Performance Level thresholds set down in their respective Service Definition Documents.

To keep you up to date on Galileo’s performance, the European GNSS Service Centre (GSC) issues quarterly reports on Galileo OS and SAR performance, these can be found on the GSC website.

Where can I find official Galileo programme documentation?

All the official programme documentation related to Galileo is published in the Programme reference documentation section on the GSC website. All the documents published in this section should be used as the reference arranged/listed by service (i.e Open Service, High Accuracy Service...)


Which are the expected performances of Galileo once fully deployed?

Expected performances of Galileo once the Full Operational Capability is reached, can be found in Annex D of the Open Service-Service Definition Document (OS SDD). In this section, the performance evolution is shown including Full Operational Capability with 24 satellites.


Is Galileo compatible with the American GPS? and with other GNSS?

Galileo is fully interoperable with GPS, and their combined use will bring many benefits to the end user. Galileo satellites will offer more usable satellites, meaning more accurate and reliable positioning and timing synchronization for end users. Navigation in cities or in complex environments, where satellite signals can often be blocked by buildings, tunnels or cut-offs, will be particularly benefitted from the higher number of satellites in view.

Galileo's accurate timing capability will also contribute to enabling more robust, reliable, efficient and resilient synchronisation for critical user’s domains as banking and financial transactions, telecommunication and energy distribution networks.

Galileo is designed to be fully interoperable with the rest of the GNSS constellations.

Is Galileo the same as GPS?


Can you use satellite navigation indoors?

When used in combination with other Global Navigation Satellite Systems (GNSS), Galileo significantly improves accuracy in challenging environments, including urban canyons and indoors. What’s more, in combination with other networks, such as 5G for example, Galileo provides the accuracy, ubiquity and security needed to support seamless indoor-outdoor navigation solutions.


Who can I contact for more information about Galileo and its services?

The European GNSS Service Centre (GSC) is available to help all Galileo users. The GSC Helpdesk can be reached at http://www.gsc-europa.eu.


What is the Galileo Open Service?

The Galileo Open Service is a free mass market service for positioning, navigation and timing that can be used by Galileo enabled chipsets in smartphones or car navigation systems, for example.


What is the Galileo Public Regulated Service?

The Public Regulated Service is for government authorised users, such as civil protection, fire brigades, customs officers and the police. It is particularly robust and fully encrypted to provide service continuity in national emergencies or crisis situations, such as terrorist attacks. Click here for more information


What is the Galileo Search and Rescue service?

The Galileo Search and Rescue (SAR) service is Europe's contribution to an international emergency beacon locating system called "Cospas-Sarsat". Galileo is the first satellite constellation to offer global SAR capability and significantly reduces the time needed to accurately locate a distress beacon. Galileo SAR also contains a unique return link that lets users know that their distress signal has been received and that help is on the way. Click here for more information.

Galileo Search and Rescue (SAR)


What is the Galileo High Accuracy Service?

Galileo’s High Accuracy Service (HAS) will complement the Open Service by providing an additional encrypted navigation signal in a different frequency band. The HAS will allow users to obtain a positioning error below two decimetres. It will be based on the free transmission of Precise Point Positioning (PPP) corrections through the Galileo E6 signal.


What are the Galileo Initial Services?

Launched in December 2016, Galileo Initial Services are the first step towards full operational capability, marking the transition from deployment and testing to operations. This means that all mass-market devices containing a Galileo-enabled chipset, such as smartphones and vehicle navigation devices, are able to use Galileo signals for positioning, navigation and timing.

The Initial Services offered by Galileo are Open Service, the Public Regulated Service (PRS) and the Search and Rescue Service (SAR). Click here for more information.

With the Declaration of Galileo Initial Services, the European Union announced that the Galileo satellites and ground infrastructure are ready for use. The conditions under which the Galileo Initial Services are being delivered, including their expected performance (accuracy, etc.) and availability, are published on the Galileo Open Service-Service Definition Document (OS SDD). Galileo Initial Services will evolve in accordance with the infrastructure deployment until the Full Operational Capability (FOC) is achieved. As a consequence, specific releases of the Service Definition Documents (OS SDD) will be issued to properly take into account such evolutions in future service declaration milestones.


What is the Galileo Authentication concept?

In Galileo, authentication will be offered in two ways:

• Open Service Navigation Message Authentication (OSNMA) that will make use of enhanced modulations (BOC variants) and encryption/authentication techniques to provide robustness against jamming and spoofing. As per the OS-NMA, it will provide users with a mean to validate that the received Navigation Message was generated by the Galileo Ground Segment.

• Commercial Authentication service (CAS) is understood as the ability to provide a level of guarantee to users regarding the use of signals and data from actual Galileo satellites and not from any other source. This capacity will increase the degree of trust on the services based on Galileo positioning and prevent spoofing of Galileo signals, which may lead to committing fraud. The purpose of this service is to satisfy the demand of GNSS users and applications of a trusted navigation solution provided by GNSS systems.


When do you expect all Galileo services to be available?

All of Galileo’s services will be available once the satellite constellation and ground infrastructure are completed, which is expected to happen by 2020. This will allow the full Galileo performance to be achieved and with maximum availability.


What is the European GNSS Service Centre (GSC)?

The European GNSS Service Centre (GSC) is set to be an integral part of the European GNSS infrastructure and provides the single interface between the Galileo system and the users of the Galileo Open Service (OS), High Accuracy Service (HAS) and Commercial Authentication Service (GSC).

The GSC is conceived as a centre of expertise, knowledge sharing, custom performance assessment, information dissemination and support to the provision of value-added services enabled by Galileo.


How can I contact and get support from GSC?

To get support from GNSS Service Centre you will need to register in the GSC website. Afterwards, any question or doubt can be raised using the Galileo Help Desk Contact Form.


Which kind of services can I obtain from GSC?

The functionality and services currently offered by GSC are:

  • Helpdesk support for general queries and incident notifications from users on Galileo.
  • Information about the system status and notifications on important events affecting the system. In addition, registered users can subscribe to be informed in real time about events affecting Galileo services. One example is the publication of Notice Advisory to Galileo Users (NAGUs), which inform regularly about the system status.
  • Electronic Library, including Programme Reference documentation and general information.
  • Support to GNSS developers, including the GNSS Simulation and Testing Infrastructure (GSTI).
  • Provision of Galileo system data.
  • Promotion of GNSS and Galileo in particular.
  • Interface with other GNSS Service Providers.
  • Monitoring of the service and measuring the level of satisfaction of Galileo and the GSC in order to propose improvements and evolve the service accordingly.


What is a NAGU?

The Notice Advisory to Galileo Users (NAGU) aims to inform the user community about the status of the Galileo constellation and, in particular, the occurrence and recovery of Signal in Space (SiS) outages. The SiS alert and warning indications received in real time by the user receivers always take precedence over the NAGU information received offline by an end user. NAGUs are published on the GSC web portal and automatic notifications to GSC registered users are sent once a new NAGU has been released. NAGUs are issued both for Planned and Unplanned events, and for General Notices regarding Galileo System as well as, for example, to notify users about the launch of new satellites. For more information about NAGUs, its format and templates, please, visit GSC site section NAGU information.


Where can I find information about the Galileo constellation status?

Updated information on the status of the Galileo constellation can be found in the “Constellation Status” section under “Service Status” menu of GSC Website.


What are the Galileo Almanacs?How do I use them?

The almanac data is a reduced-precision subset of the clock and ephemeris parameters of the active satellites in orbit. The almanac data allow to compute a raw estimation of the satellite coordinates, which is needed for signal acquisition by the receiver. The user receiver utilises the algorithm described in the Galileo Open Service Signal-In-Space Interface Control Document (OS SIS ICD) to compute the positions of the Galileo satellites. The definition of the Galileo almanac parameters can be found in section 5.1.10 of the OS SIS ICD.


How can I test if my smartphone is receiving Galileo signals?

To check if a smartphone receives any Galileo satellite signals, there are several apps available in your app store such as GPSTest app (only available for Android). The application takes some time to locate the satellites. To make sure that the device tracks Galileo satellites, it is needed to be in an open space and without wifi or data connection enabled, to avoid getting almanacs from the internet. To have an idea of what can be seen on your phone, you can watch the following video. Additionally, some useful help information to test the device can be found in the following document.


What are the Galileo Satellite Metadata? How do I use them?

The Galileo Satellite Metadata is information about the satellite properties which need to be known in order to properly implement advanced processing algorithms for precise orbit determination or Precise Point Positioning (PPP). This includes physical characteristics (such as mass, area or reflectivity), the attitude law and antenna parameters.


Is the GSC services portfolio offered to users going to increase? How?

Yes, when fully developed, the European GNSS Service Centre (GSC) will offer a range of additional services, such as:

  • Providing the interfaces between the Galileo System and the new services (HAS, CAS, OSNMA).
  • Supporting the management of future services. Increase the number of Galileo-related products.
  • Providing service performance assessment forecasts.
  • Providing orbital products to SAR users.


How do I know if my equipment is Galileo enabled?

In www.usegalileo.eu website it is possible to consult a complete list of different Galileo enabled receivers, chipsets or modules that can be found on the market classified by sector and type of device.


Are there multi-constellation receivers capable of using GPS, Galileo, Glonass and others?

According to a recent GSA-supported study, chipset and receiver manufacturers are already equipping their devices with multi-constellation capabilities, including Galileo, and taking advantage of available services. In fact, the vast majority of current receivers are multi-constellation, and the most popular way to provide multi-constellation support is to cover all constellations, which represents over 30% of receivers.

To further increase the level of Galileo integration, the GSA continues to work directly with chipset and receiver manufacturers. Through user consultations, technology workshops, sharing Galileo updates, co-marketing efforts, and dedicated funding for receiver development projects and studies, the GSA is working with manufacturers to build an even better navigation experience.

The GSA also launched its Fundamental Elements programme, a new research and development (R&D) funding mechanism supporting the development of chipsets and receivers. The programme will run through 2020 and has a projected budget of over EUR 100 million. The main objective of the initiative is to facilitate the development of applications across different sectors of the economy and promote the development of such fundamental elements as Galileo-enabled chipsets and receivers.


Can I use Galileo on my mobile phone?

There are already over 700 million Galileo-enabled smartphones on the market and this number is increasingly rapidly.

Click here to find out if your phone is Galileo-enabled.


Can I use Galileo in my car?

Galileo- enabled navigation devices for your car are already available on the market. What’s more, since April 2018, all new type approved vehicles sold in Europe are Galileo capable as part of a requirement to comply with the EU’s eCall emergency response system regulation.

Click here to find out if your navigation device is Galileo-enabled.


Where can companies get information to help them develop products and services to take advantage of Galileo signals?

The European GNSS Service Centre (GSC) is the place to go for all things related to developing Galileo-capable products and services.

The GSC can be contacted at www.gsc-europa.eu


Can I use Galileo enabled devices in other regions of the world?

Yes, Galileo offers its services worldwide with no restrictions in the use of its signal in any place of the planet, unless local governments do not allow access to any of the specific services.

GSA works with other countries and GNSS systems to enable and harmonise the Galileo services provision. For instance, the U.S. Federal Communications Commission (FCC) granted the access to specific signals transmitted by Galileo in all the devices in the United States of America.

More information can be found here