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Galileo Future and Evolutions

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Title Galileo Future and Evolutions
Edited by GMV
Level Basic
Year of Publication 2011
Logo GMV.png

The Galileo program is Europe's initiative for a state-of-the-art global satellite navigation system, providing a highly accurate, guaranteed global positioning service under civilian control.[1] While providing autonomous navigation and positioning services, the system established under the Galileo program is at the same time interoperable with other GNSS systems such as GPS and GLONASS. The system, once fully deployed, will consist of 30 satellites, to be deployed in a staggered approach, and the associated ground infrastructure.[2]

Galileo phases

The Galileo program has been structured according to three main phases:[3][4]

  1. In-Orbit Validation (IOV) phase:
    The IOV phase consisted of qualifying the system through tests and the operation of two experimental satellites and a reduced constellation of four operational satellites and their related ground infrastructure.
    The two experimental satellites were launched in respectively December 2005 and April 2008. Their purpose was to characterize the Medium-Earth Orbit (MEO) environment (radiations, magnetic field etc) and to test in such environment the performance of critical payload technology (atomic clocks and radiation hardened digital technology). They also provided an early experimental signal-in-space allowing securing the frequency spectrum required for Galileo in accordance with WRC RNSS allocations. The first 2 Galileo operational satellites were launched by ESA with the Soyuz VS01 flight on 21st October 2011 and were declared fully operational since April 2012. The next two Galileo satellites, completing the IOV quartet, were launched on 12th October 2012 by the Soyuz ST-B launcher from the Guiana Space Centre (please refer to ESA website for videos on the launches) and they are transmitting signals on E1, E5 and E6 band since December 2012. More information on the Galileo IOV Satellites can be found here. The first position fix using the IOV satellite quartet, was reported on the 12th of March 2013 by ESA's navigation laboratory in the Netherlands. After that ESA started a wide variety of IOV tests all across Europe to assess the performance of the system sub-set already deployed. As of February 2014 Galileo achieved In-Orbit Validation since the results of the tests shown that "Galileo works, and it works well". The performance to be achieved will effectively be reached as more satellites are launched and ground stations come on line.[5][6]
  2. Initial Operational Capability (IOC) phase:
    The IOC stage represents the partial commissioning of the ground and space infrastructure as from 2014-2015 and the provision of the Open Service, the Search And Rescue service and the PRS.The provision of these Galileo Initial Services was declared in December 2016.[7] The procurement of the IOC phase included the first batch of satellites (14 additional satellites to the 4 IOV satellites), the launch services, the needed mission and control ground infrastructure, the system support services and the corresponding operations[8]. Details on the different steps of this phase are presented in Galileo Deployment
  3. Full Operational Capability (FOC) phase:
    The FOC phase consists of the deployment of the full system which will consist of 30 satellites, control centres located in Europe and a network of sensor stations and uplink stations installed around the globe. Galileo's Full Operational Capability (FOC) is expected for 2020, in a staggered approach from the IOC phase. Four new Galileo satellites were put on orbit on top of an Ariane 5, on July 25, 2018 from the European spaceport in Kourou, French Guiana. This launch brings the Galileo constellation finalization, with all objectives achieved: Galileo signal is better than expected and now usable in all new mobile phones.

The list of past and present satellites of the Galileo navigation system, as well as the following satellite launches, can be consulted in[9]

The definition phase and the development and In-Orbit Validation phase of the Galileo program was carried out by the European Space Agency (ESA) and co-funded by ESA and the European Union. The Full Operational Capability phase of the Galileo program is fully funded by the European Union and managed by the European Commission. The Commission and ESA signed a delegation agreement by which ESA acts as design and procurement agent on behalf of the Commission.

Galileo Deployment

Galileo’s seventh and eighth satellites launched successfully in March 2015. The European Space Agency (ESA) planned four more satellites to reach orbit in that year, and space maneuvers for Galileo 5 and 6 were completed, with a recovery plan currently under study. Both satellites 7 and 8 started transmitting signals in May 2015, with the first E1 and E5 signals from Galileo 8 received on May 21 and the first E1 and E5 signals from Galileo 7 on May 25.[10]
A further two Galileo satellites were successfully launched on September 11, 2015, raising the total number of satellites in the constellation to 10. [11] Several stations participating in the International GNSS Service Multi-GNSS Experiment started tracking the new satellites on October 12th, 2015. [12]
The 11th and 12th Galileo satellites were launched on December 17, 2015 [13] and became operational in the end of April 2016 [14].
The total number of satellites in the constellation was increased to 14 on May 24, 2016, with the launch of two additional satellites from the French Guiana [15]

On November 17th, 2016, the Galileo constellation was reinforced with another 4 satellites. [16]

With this last launch, Galileo became operational for initial services on December 15th, 2016. [7]. Four new Galileo satellites were successfully launched on December 12th, 2017. This last launch brings the Galileo constellation to a total of 22 satellites.

On April 2017, the Galileo Search And Rescue (SAR) service was officially launched. This new service reduces the detection delay of a distress signal from up to several hours to 10 minutes. The a return link, a signal informing the person in distress that the signal has been received and localized, was declared in January 2020.[17]

Galileo OS-NMA capability is gradually being added to Galileo Open Service in the short term. It is currently under public testing phase[18], before being officially provided as part of Galileo services.

Regarding Galileo High Accuracy, this service will be implemented in a three-step approach[19][20]:

  • Phase 0 (HA testing and experimentation), starting in Q2 2021 focusing on activities aimed at validating Galileo’s dissemination capabilities through the E6B channel and performing initial high-accuracy testing. Internal testing is ongoing since 2019.
  • Phase 1 (HA Initial Service) from 2022. Provision of an initial Galileo High Accuracy Service resulting from the implementation of a high-accuracy data generation system processing Galileo system data only. The HA initial service will deliver Service Level 1 only with a reduced performance (below the full service’s targets).
  • Phase 2 (HA Full Service). Full provision of the Galileo High Accuracy Service starting from 2024, including Service Level 1 and Service Level 2, fulfilling its target performance (e.g. 20cm positioning performance).

Galileo Evolutions

Galileo Clock (artistic interpretation)

The European Parliament and the Council allocated the management of the Galileo programme to the European Commission.[21] The European Commission set up a consultative group of GNSS experts called the Mission Evolution Advisory Group (MEAG). MEAG aims at providing EC with independent advice and recommendations on potential evolutions of the mission objectives and the service definitions for the European satellite navigation programmes Galileo and EGNOS.[22] The group is expected to critically assess changes of both user needs and scope of space-based PNT, both on European and international scale. Changes on the mission and service requirements for the Galileo and EGNOS programme could be analysed too, proposing suitable updates of the mission and service baseline. MEAG members include experts from GNSS user communities, GNSS industry sectors, academia, national space agencies and other recognized experts from Member States. The MEAG meets on a regular basis with an indicative number of three meetings per year. The expert group may establish on an ad-hoc basis Working Groups to provide specialist support as required to carry out its activities. The MEAG shall further record and report its work results and recommendations on a yearly basis to the Commission.

In April 2013, the member states' Permanent Representatives (Coreper) endorsed the compromise reached between the Council and the European Parliament in their negotiations on a new financial and governance framework for the European satellite navigation systems (EGNOS and Galileo) for the period covered by the multi-annual financial framework for 2014-2020[23].

The draft regulation contains the following key elements based on a first proposal presented by the Commission in December 2011, excluding the financial envelope[23]:

  • A tentative budget of EUR 6.3 billion (at constant 2011 prices), to be fully financed from the EU budget.
  • A definition of the EU satellite navigation systems and Programmes and of the services they will provide;
  • A new governance framework that establishes a strict division of tasks between the Commission, the European GNSS Agency and the European Space Agency;
  • Rules on public procurement, promoting the widest participation possible throughout the Union and ensuring fair competition conditions.

The Galileo Evolutions are currently under technical study within the European GNSS Evolution Programme (EGEP),[24] an ESA optional programme supported by 17 Member States and Canada. Its primary aim is to undertake research and development in and verification of technologies relating to regional space-based augmentation systems (SBAS) and global navigation satellite systems (GNSS). Regarding Galileo, EGEP objectives are:

  • define future system architectures for Galileo and prepare the technology for future versions of the system;
  • provide testbeds and system tools;
  • improve Agency knowledge of GNSS performance monitoring and the principal environmental factors influencing performance;
  • promote and support scientific exploitation of Galileo.

Another main objective of the EGEP is the preparation of the future generation of Galileo (Galileo Second Generation, G2G), the progressive introduction of which is foreseen in the first years of the 2020s, when the first launched Galileo satellites will reach the end of their operational life. The G2G activities include studies on the benefits, feasibility and impact of the different concepts on which the analysis will focus (at system level, in the ground segment, payloads and other areas). One of its main objectives is the compilation of all these studies for the elaboration of a possible frame of reference for the Second Generation of Galileo, also incorporating the lessons learned from the first generation.[25]

The Galileo Second Generation (G2G) is expected to deliver improved performance and RNP (Required Navigation Performances) features such as reliability, maintainability, availability, continuity, accuracy and integrity. This is why the European Commission (EC) has decided to launch a Transition Programme with ESA for technical definition and implementation.

The constant need for orbital spare parts to replace end-of-life GALILEO satellites must be taken into account, which will ensure that the European system continues to operate without losing the availability of services. In 2017, twelve additional satellites were requested from the industry to serve as a transition to a future generation, with the objective of maintaining and improving the precision, robustness, availability and integrity performance in its main PNT (Positioning, Navigation and Time) function, as a permanent part of the European and global landscape in the Global Navigation Satellite System (GNSS) and to confer European autonomy over its constellation, for civil use and with governmental applications.

The G2G system and technological development are being supported through ESA's HSNAV GNSS and H2020 Programmes, delegating their technical definition and the management of their activities related to their implementation, guaranteeing compatibility with previous versions, the continuity of Galileo services and their possible integration with Augmentation Systems (SBAS), in the European case, is the EGNOS system, which consists of three additional satellites.