EGNOS Future and Evolutions

EGNOS
Title	EGNOS Future and Evolutions
Edited by	GMV
Level	Basic
Year of Publication	2011

The European Commission (EC) intends to ensure the future of EGNOS services for GPS L1 legacy users until at least 2030. In this context, the budget should be secured to operate the system and manage the system obsolescence. Moreover, major EGNOS system evolutions (EGNOS V3) towards a multi frequency and multi constellation configuration are currently being assessed with the objective to have them operational by 2025.

A technical assessment of the potential EGNOS evolution, EGNOS V3, is currently done by the European Space Agency within the European GNSS Evolution Programme. Airbus has been selected by the European Space Agency (ESA) as the prime contractor to develop EGNOS V3, leading a consortium with partners from France, Germany, Spain and Switzerland. Airbus is responsible for the development, integration, deployment and preparation of EGNOS V3 operations, the overall performance of the system and the Central Processing Facility which is the heart of the real time navigation algorithms. During the 6.5 year contract, around 100 people and 20 subcontractors will work on delivering the EGNOS V3 system. In 2023, the single frequency version will be available to replace the current operational version and, 18 months later, the final version in dual frequency will be delivered. EGNOS is composed of a large network of about 50 ground stations deployed over Europe, Africa and North America, two master control centres located near Rome and Madrid, and a System Operation Support Centre in Toulouse. EGNOS will also use geostationary satellites navigation payload.

EGNOS Mission Roadmap and EGNOS Evolutions

The European Parliament and the Council assigned the management of the EGNOS programme to the European Commission. On the other hand, ESA is the technical player responsible for system design and development, and ESSP is the service provider.

The European Commission, in its role of entity in charge of the management of the EGNOS programme, is defining the roadmap for the evolution of the EGNOS mission. This roadmap should cope with legacy and new missions:

• 2011-2030: En-route / NPA / APV1 / LPV200 service based on augmentation of GPS L1 only. The Safety Of Life (SoL) service is being offered by EGNOS from early 2011 on a regional basis and this will be guaranteed up to 2030 in compliance with ICAO SBAS SARPS. The service is thus compliant with the aviation requirements for Approaches with Vertical Guidance (APV-I) and Category I precision approaches, as defined by ICAO in Annex 10. In order to grant this timeframe, it is still needed to achieve a programmatic commitment based on secured funds.
• 2020+: It is planned that EGNOS will experiment a major evolution by 2025, EGNOS V3, including the fulfilment of the SBAS L1/L5 standard, expansion to dual-frequency, and evolution toward a multi-constellation concept.

To support this mission roadmap, EGNOS needs to evolve. This evolution is divided into minor updates of the current EGNOS version, EGNOS V2, and a major evolution leading to the provision of new services, EGNOS V3.

The minor evolutions in the current EGNOS version are performed in a regular basis at an approximate pace of an update per year, and aim at solving infrastructure obsolescence issues, at supporting the LPV200 service beyond APV1 and at improving the operation of the system.

The major evolution requires a full dedicated engineering cycle starting from the definition of the mission of the system highly coupled with a technical feasibility analysis in coordination with the evolution of the SBAS standards.

As regards the consolidation of the new EGNOS missions, 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. 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 may 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.

As for the EGNOS technical evolution, ESA is managing several activities within the European GNSS Evolution Programme (see below).
The European Commission and the European Space Agency are very active in the different international co-operation fora in SBAS standardisation and SBAS interoperability ensuring the co-ordination of the EGNOS evolution with that of the other SBAS in the world.

On September 2015, after extensive ground and space testing, the SES-5 GEO satellite entered into the EGNOS operational platform, replacing Inmarsat-4F2. The satellite ensures reliable EGNOS services until 2026. It has been introduced through EGNOS System Release V241M, which enables a range of performance improvements.

Changes in the EGNOS Space Segment configuration have been introduced in order to use the newest GEO satellites in detriment of the older ones. See EGNOS Space Segment for details regarding the current operational platform.

The European GNSS Evolution Programme

The European GNSS Evolution Programme (EGEP) is an ESA optional programme supported by 17 Member States and Canada which was defined in 2006 by ESA to address the second generation of the EGNOS and Galileo systems.

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). Through forward-looking activities, the programme ensures that European industry has timely availability of competitive and innovative capabilities required for the evolution of EGNOS and Galileo. This applies to future requirements in the short, medium and long term.

EGEP also provides a framework for scientific research enabled by GNSS, which spans a wide range of disciplines, from atmosphere and climate modelling through time and space references to fundamental physics. The programme is being implemented through activities anchored in Work Plans that are being successively defined by the Agency and approved by the Participating States according to the following objectives:

• begin defining future system architectures for EGNOS and Galileo and prepare the technology for future versions of these systems
• support the definition of how to implement the next version of EGNOS, and prepare the technology for it
• 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 EGNOS and Galileo

Among many other tasks, the first phase of this programme included two parallel studies about the concept of Multi-Constellation Regional System (MRS) over 2007-2009. An outcome of this work was a generic MRS architecture baseline that should be considered as a candidate target for V3 functional architecture and further assessed and refined within the EGNOS V3 phase A definition study.

The second phase of EGEP on SBAS (over 2010-2011) is devoted to the consolidation of system evolutions and to field testing. It is broken down into three main parts:

• EGNOS V3 Definition Phase, aiming at preparing the new EGNOS system generation to address obsolescence issues, robustness improvement, new services, standard evolutions, coverage extension, use of new broadcast means, with a view to start preparing the EGNOS V3 implementation phase at a later stage (post 2013).
• Experimentations with several Test-Beds based on using a complete or partial SPEED (Support Platform for EGNOS Evolutions & Demonstrations) infrastructure.
• SPEED related activities in order to procure, install, operate and maintain the SPEED V1 engineering platform allowing to run the above tests and to develop an upgraded version of SPEED V1 platform to implement new features in the Host Structure of SPEED necessary to support a second phase of experimentations (at a later stage).

The above-mentioned test-beds have the following objectives:

• HIS (High Integrity Service) to develop one system Test Bed (based on SPEED) to engineer and experiment high Integrity (similar to Safety Of Life for multi-modal applications) and authentication (authenticated GEO signal + GEO ranging/UDRE).
• ARCTIC to experiment maritime and aeronautics services in northern latitudes.
• HPS (High Precision Service) to demonstrate and generate interest in an HPS service (with integrity), based on, first GPS and later GPS+GALILEO.
• MLU (MRS Land User service) to investigate, demonstrate and develop new services for Land Users: Proof of Position, Authentication and Emergency Services.

In 2011, two parallel contracts have been commissioned by ESA to perform a Phase A (feasibility) study of EGNOS V3 Phase A. These studies are considering different target missions with different levels of consolidation:

• Consolidated Missions:
  • Provide GPS L1-only augmentation to ensure EGNOS service to legacy users at least until 2030.
  • Provide GPS dual frequency augmentation for LPV-200 service in Europe, Middle-East and Africa.
  • Provide GPS and GALILEO dual frequency augmentation to provide robust (to constellation depletion) LPV-200 service in Europe, Middle-East and Africa.

• Missions to be consolidated:
  • Provide GPS and GALILEO dual frequency augmentation for an enhanced service (lower Vertical Alert Limit than LPV-200) in current European Union (EU27) plus Switzerland and Norway.
  • Provide robustness to the loss of one frequency in EU27 plus Switzerland and Norway.

Concerning the provision of additional services (i.e.: support to ADS-B, maritime, high precision, land-users…), the objective is that the design will ensure that EGNOS has sufficient in-built expandability and upgradeability capabilities to allow the provision of new products.