European Geostationary Navigation Overlay Service
Encyclopedia
The European Geostationary Navigation Overlay Service (EGNOS) is a satellite based augmentation system (SBAS) developed by the European Space Agency
, the European Commission
and EUROCONTROL. It supplements the GPS, GLONASS
and Galileo systems by reporting on the reliability and accuracy of the signals. The official start of operations was announced by the European Commission on 1 October 2009.
According to specifications, horizontal position accuracy should be better than seven metres. In practice, the horizontal position accuracy is at the metre level. The EGNOS system consists of three geostationary satellites and a network of ground stations.
The system started its initial operations in July 2005, showing outstanding performances in terms of accuracy (better than two metres) and availability (above 99%); and it was certified for use in safety of life applications in March 2011. A commercial service is under test and will also be made available in 2011.
Similar service is provided in North America by the Wide Area Augmentation System
(WAAS), and in Asia, notably Japan, by the Multi-functional Satellite Augmentation System
(MSAS).
On 28 July 2005, the European Space Agency
announced it had signed a contract with an operating company, European Satellite Services Provider
, to run EGNOS. 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.
Initial work to extend EGNOS coverage to the Southern Africa region is currently being undertaken.
users which enjoy unperturbed reception of direct signals from geostationary satellites up to very high latitude
s. The use of EGNOS on the ground, especially in urban areas, is limited due to relatively low elevation
of geostationary satellites: about 30° above horizon
in central Europe
and much less in the North of Europe. To address this problem, ESA released in 2002 SISNeT, an Internet
service designed for continuous delivery of EGNOS signals to ground users. The first experimental SISNeT receiver was created by the Finnish Geodetic Institutehttp://www.esa.int/esaNA/ESAW0OZPD4D_index_0.html. The commercial SISNeT receivers have been developed by Septentrio
.
34 RIMS (Ranging and Integrity Monitoring Stations) - receiving signals from US GPS satellites,
4 MCC (Mission Control Centers) - data processing and differential corrections counting ,
6 NLES (Navigation Land Earth Stations) - accuracy and reliability data sending to three geostationary satellite transponders to allow end-user devices to receive them.
European Space Agency
The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...
, the European Commission
European Commission
The European Commission is the executive body of the European Union. The body is responsible for proposing legislation, implementing decisions, upholding the Union's treaties and the general day-to-day running of the Union....
and EUROCONTROL. It supplements the GPS, GLONASS
GLONASS
GLONASS , acronym for Globalnaya navigatsionnaya sputnikovaya sistema or Global Navigation Satellite System, is a radio-based satellite navigation system operated for the Russian government by the Russian Space Forces...
and Galileo systems by reporting on the reliability and accuracy of the signals. The official start of operations was announced by the European Commission on 1 October 2009.
According to specifications, horizontal position accuracy should be better than seven metres. In practice, the horizontal position accuracy is at the metre level. The EGNOS system consists of three geostationary satellites and a network of ground stations.
The system started its initial operations in July 2005, showing outstanding performances in terms of accuracy (better than two metres) and availability (above 99%); and it was certified for use in safety of life applications in March 2011. A commercial service is under test and will also be made available in 2011.
Similar service is provided in North America by the Wide Area Augmentation System
Wide Area Augmentation System
The Wide Area Augmentation System is an air navigation aid developed by the Federal Aviation Administration to augment the Global Positioning System , with the goal of improving its accuracy, integrity, and availability...
(WAAS), and in Asia, notably Japan, by the Multi-functional Satellite Augmentation System
Multi-functional Satellite Augmentation System
Multi-functional Satellite Augmentation System is a Japanese SBAS , i.e. a satellite navigation system which supports differential GPS designed to supplement the GPS system by reporting on the reliability and accuracy of those signals...
(MSAS).
On 28 July 2005, the European Space Agency
European Space Agency
The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...
announced it had signed a contract with an operating company, European Satellite Services Provider
European Satellite Services Provider
European Satellite Services Provider is a company set up to provide the EGNOS Open Service and Safety of Life Service compliant with ICAO Standards and Recommended Practices throughout the ECAC region, including the operations and technical management of EGNOS, the European Geostationary...
, to run EGNOS. 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
Tour de France
The Tour de France is an annual bicycle race held in France and nearby countries. First staged in 1903, the race covers more than and lasts three weeks. As the best known and most prestigious of cycling's three "Grand Tours", the Tour de France attracts riders and teams from around the world. The...
road race.
Initial work to extend EGNOS coverage to the Southern Africa region is currently being undertaken.
Satellites
Similar to WAAS, EGNOS is mostly designed for aviationAviation
Aviation is the design, development, production, operation, and use of aircraft, especially heavier-than-air aircraft. Aviation is derived from avis, the Latin word for bird.-History:...
users which enjoy unperturbed reception of direct signals from geostationary satellites up to very high latitude
Latitude
In geography, the latitude of a location on the Earth is the angular distance of that location south or north of the Equator. The latitude is an angle, and is usually measured in degrees . The equator has a latitude of 0°, the North pole has a latitude of 90° north , and the South pole has a...
s. The use of EGNOS on the ground, especially in urban areas, is limited due to relatively low elevation
Elevation
The elevation of a geographic location is its height above a fixed reference point, most commonly a reference geoid, a mathematical model of the Earth's sea level as an equipotential gravitational surface ....
of geostationary satellites: about 30° above horizon
Horizon
The horizon is the apparent line that separates earth from sky, the line that divides all visible directions into two categories: those that intersect the Earth's surface, and those that do not. At many locations, the true horizon is obscured by trees, buildings, mountains, etc., and the resulting...
in central Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
and much less in the North of Europe. To address this problem, ESA released in 2002 SISNeT, an Internet
Internet
The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite to serve billions of users worldwide...
service designed for continuous delivery of EGNOS signals to ground users. The first experimental SISNeT receiver was created by the Finnish Geodetic Institutehttp://www.esa.int/esaNA/ESAW0OZPD4D_index_0.html. The commercial SISNeT receivers have been developed by Septentrio
Septentrio
Septentrio is a designer and manufacturer of high-end multi-frequency GNSS receivers. Its main target is to provide GNSS receiver boards for further system integration by Original Equipment Manufacturers...
.
| Satellite Name & Details | NMEA / PRN | Location |
|---|---|---|
| Inmarsat 3-F2 (Atlantic Ocean Region-East) | NMEA #33 / PRN #120 | 15.5°W |
| ARTEMIS | NMEA #37 / PRN #124 | 21.5°E |
| Inmarsat 4-F2 (Europe Middle East Africa) | NMEA #39 / PRN #126 | 25°E |
| Inmarsat 3-F1 (Indian Ocean) | NMEA #44 / PRN #131 | 64.5°E |
| Astra 4B (a.k.a Sirius 5 or SES-5) http://www.ses-astra.com/business/en/solutions/government/case-studies/egnos/index.php | launch in 2011 | 5.0°E |
| Astra 5B http://www.ses-astra.com/business/en/solutions/government/case-studies/egnos/index.php | launch in 2013 | 31.5°E |
Ground stations
More than 40 ground stations are linked together to create EGNOS network which consists:34 RIMS (Ranging and Integrity Monitoring Stations) - receiving signals from US GPS satellites,
4 MCC (Mission Control Centers) - data processing and differential corrections counting ,
6 NLES (Navigation Land Earth Stations) - accuracy and reliability data sending to three geostationary satellite transponders to allow end-user devices to receive them.
External links
- European Commission information on EGNOS
- EGNOS Portal for application developers
- 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
- European Space Agency information on EGNOS for Professionals
- Learning EGNOS
- ESESA - EGNOS Service Extension to South Africa
- Usman A Zahidi, "EGNOS enabled GPS Software Receiver" Report Page,
- Information on WAAS, EGNOS & MSAS