European Geostationary Navigation Overlay Service
 | |
| Country/ies of origin | European Union |
|---|---|
| Operator(s) | EUSPA, ESA |
| Type | Augmentation |
| Status | Operational |
| Coverage | Europe, North Africa |
| Other details | |
| Cost | €1,1 billion |
| Website | EGNOS |
The European Geostationary Navigation Overlay Service (EGNOS) is a
EGNOS consists of 40 Ranging Integrity Monitoring Stations, 2 Mission Control Centres, 6 Navigation Land Earth Stations, the EGNOS Wide Area Network (EWAN), and 3
According to specifications, horizontal position accuracy when using EGNOS-provided corrections should be better than seven metres. In practice, the horizontal position accuracy is at the metre level.
Similar service is provided in North America by the
Galileo and EGNOS budget for the 2021–2027 period is €9 billion[2]
History and roadmap
The system started its initial operations in July 2005, with accuracy better than two metres and availability above 99%. As of July 2005, EGNOS has been broadcasting a continuous signal, and at the end of July 2005, the system was again used to track cyclists in the Tour de France road race.[3]
In 2009, the European Commission announced it had signed a contract with the company European Satellite Services Provider to run EGNOS. The official start of operations was announced by the European Commission on 1 October 2009.[4] The system was certified for use in safety of life applications in March 2011.[5] An EGNOS Data Access Service became available in July 2012.
Initial work to extend EGNOS coverage to the Southern Africa region is being done under a project called ESESA - EGNOS Service Extension to South Africa.[6]
The European Commission is defining the roadmap for the evolution of the EGNOS mission. This roadmap should cope with legacy and new missions:[7]
- 2011–2030: En-route / NPA / APV1 / LPV200 service based on augmentation of GPS L1 only. The Safety of Life (SoL) will be guaranteed up to 2030 in compliance with ICAO SBAS SARPS.
- 2020+: It is planned that EGNOS will experiment with a major evolution, EGNOS V3, including the fulfilment of the SBAS L1/L5 standard, expansion to dual-frequency, and evolution toward a multi-constellation concept.
In 2021, following Brexit, the United Kingdom withdrew regulatory approval for EGNOS, and aircraft pilots were no longer permitted to use the system.[8]
Satellites and SISNeT
| Satellite Name & Details | NMEA / PRN | Signals | Location | Status[9] |
|---|---|---|---|---|
| Inmarsat 3-F2 (Atlantic Ocean Region-East[10]) | NMEA #33 / PRN #120 | L1 | 15.5°W | retired |
| ARTEMIS [11] | NMEA #37 / PRN #124 | - | 21.5°E | retired |
| Inmarsat 4-F2 (Europe Middle East Africa[12]) | NMEA #39 / PRN #126 | - | 64°E | testing |
| Inmarsat 3-F1 (Indian Ocean[13]) | NMEA #44 / PRN #131 | - | 64.5°E | retired |
| SES-5 (a.k.a. Sirius 5 or Astra 4B) [14][15] | NMEA #49 / PRN #136[16] | L1 & L5 | 5.0°E | active |
| Astra 5B[14][15] | NMEA #36 / PRN #123[16] | L1 & L5 | 31.5°E | active |
| Eutelsat 5 West B | 5°W | launched in October 2019, it will use EGNOS 3 |
Similar to
Services
- Open Service (OS): It improves positioning accuracy by correcting error sources affecting GNSS signals intended for a wide range of applications in various domains. The corrections transmitted by EGNOS help mitigate the ranging error sources related to satellite clocks, satellite position and ionospheric effects. EGNOS can also detect distortions affecting the signals transmitted by GNSS and prevent users from tracking unhealthy or misleading signals that could lead to inaccurate positioning. The service is available free-of-charge in Europe to any user equipped with an appropriate GPS/SBAS compatible receiver for which no specific receiver certification is required. It has been available since 1 October 2009.[21]
- Safety of Life (SoL) Service: The main objective of the EGNOS SoL service is to support civil aviation operations down to Localizer Performance with Vertical Guidance (LPV) minima. However, the EGNOS SoL service might also be used in a wide range of other application domains (e.g. maritime, rail, road...) in the future. This service provides the most stringent level of signal-in-space performance to all Safety of Life user communities. The EGNOS system has been designed so that the EGNOS Signal-In-Space (SIS) is compliant with the ICAO SARPs for SBAS. It has been available since 2 March 2011.
- EGNOS Data Access Service (EDAS): EDAS is the terrestrial data service and offers ground-based access to EGNOS data in real time and also in a historical FTP archive to authorised users (e.g. added-value application providers). EDAS is the single point of access for the data collected and generated by the EGNOS ground infrastructure distributed over Europe and North Africa, it is aimed at users who require enhanced performance for commercial and professional use. It has been available since 26 July 2012.[22]
Architecture
EGNOS is divided into four functional segments:
1. Ground segment: comprises a network of 40 Ranging Integrity Monitoring Stations (RIMS), 2 Mission Control Centres (MCC), 2 Navigation Land Earth Stations (NLES) per Geostationary Earth Orbit (GEO), and the EGNOS Wide Area Network (EWAN), which provides the communication network for all the components of the ground segment.
- 40 RIMS: the main function of the RIMS is to collect measurements from GPS satellites and to transmit these raw data every second to the Central Processing Facilities (CPF) of each MCC.
- 2 MCC: these receive the information from the RIMS and generate correction messages to improve satellite signal accuracy and information messages on the status of the satellites (integrity). It acts as the "brain" of the system.
- 6 NLES: the NLESs (two for each GEO for redundancy purposes) transmit the EGNOS message received from the central processing facility to the GEO satellites for broadcasting to users and to ensure the synchronisation with the GPS signal.
2. Support segment: In addition to the above-mentioned stations/centres, the system has other ground support installations involved in system operations planning and performance assessment, namely the Performance Assessment and Checkout Facility (PACF) and the Application Specific Qualification Facility (ASQF) which are operated by the EGNOS Service Provider (ESSP).
- PACF (Performance Assessment and Check-out Facility): provides support to EGNOS management in the form of performance analysis, troubleshooting, and operational procedures as well upgrading specifications and validations and providing maintenance support.
- ASQF (Application Specific Qualification Facility): provides civil aviation and aeronautical certification authorities with the tools to qualify, validate and certify the different EGNOS applications.
3. Space Segment: composed of at least three geostationary satellites broadcasting corrections and integrity information for GPS satellites in the L1 frequency band (1575.42 MHz). This space segment configuration provides a high level of redundancy over the whole service area in the event of a failure in the geostationary satellite link. EGNOS operations are handled in such a way that, at any point in time, at least two GEOs broadcast an operational signal.
4. User Segment: the EGNOS user segment consists of EGNOS receivers that enable their users to accurately compute their positions with integrity. To receive EGNOS signals, the end user must use an EGNOS-compatible receiver. Currently, EGNOS compatible receivers are available for such market segments as agriculture, aviation, maritime, rail, mapping/surveying, road and location based services (LBS).[23][22]
Aviation
In March 2011, the EGNOS Safety-of-Life Service was deemed acceptable for use in aviation. This allows pilots throughout Europe to use the EGNOS system as a form of positioning during an approach, and allows pilots to land the aircraft in IMC using a GPS approach.[24]
As of September 2018 LPV (Localizer performance with vertical guidance) landing procedures, which are EGNOS-enabled, were available at more than 180 airports across Europe.[25]
References
- ^ "EGNOS System". March 2016.
- ^ "EU space policy". www.consilium.europa.eu. Retrieved 2020-12-29.
- ESA. 2 August 2013. Retrieved 31 January 2016.
- ESA. 1 October 2009. Retrieved 31 January 2016.
- ESA. 2 March 2011. Retrieved 31 January 2016.
- ^ "What is ESESA?". ESESA. Retrieved 31 January 2016.
- ESA/ NAVIPEDIA. 16 October 2015. Retrieved 31 January 2016.
- ^ "Withdrawal of EGNOS for UK users - Royal Institute of Navigation".
- ^ "REALTIME | Egnos User Support". ESSP-SAS. Retrieved 31 January 2016.
- ^ "Inmarsat 3-F2". NSSDCA Master Catalog. NASA.
- ^ "Artemis". NSSDCA Master Catalog. NASA.
- ^ "Inmarsat 4-F2". NSSDCA Master Catalog. NASA.
- ^ "Inmarsat 3-F1". NSSDCA Master Catalog. NASA.
- ^ a b "EGNOS Case Study". SES. Archived from the original on 2009-05-28.
- ^ a b Beyond Frontiers Broadgate Publications (September 2016) pp97
- ^ a b "The Almanac". Retrieved 2015-10-01.
- ESA. 19 September 2002. Retrieved 31 January 2016.
- ESA. Retrieved 31 January 2016.
- ESA. 6 September 2002. Retrieved 31 January 2016.
- ESA. 25 October 2005. Retrieved 31 January 2016.
- ^ "ABOUT OS | EGNOS User Support". egnos-user-support.essp-sas.eu. Retrieved 2020-12-29.
- ^ a b "About EGNOS | EGNOS User Support". egnos-user-support.essp-sas.eu. Retrieved 2020-12-29.
- ^ "EGNOS System". www.gsa.europa.eu. 2016-03-01. Retrieved 2020-12-29.
- ^ "What is EGNOS?".
- ^ "Precision EGNOS satnav sparking quiet revolution in aircraft landings". European Space Agency. 4 September 2018. Retrieved 3 May 2020.
External links
- European Commission information on EGNOS
- Website of the EGNOS operator ESSP SaS
- EGNOS Operations User Support
- ESA information on EGNOS
- The EGNOS book, ESA Publications, Javier Ventura-Traveset and Didier Flament Archived 2020-07-19 at the Wayback Machine
- European Space Agency information on EGNOS for Professionals Archived 2020-07-19 at the Wayback Machine
- Learning EGNOS
- ESESA - EGNOS Service Extension to South Africa
- Usman A Zahidi, "EGNOS enabled GPS Software Receiver" Report Page, [1]
- Information on WAAS, EGNOS & MSAS Archived 2021-02-11 at the Wayback Machine
- Navipedia information on EGNOS—Wiki initiated by the European Space Agency
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Future missions in italics
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