![EGNOS map](https://upload.wikimedia.org/wikipedia/commons/b/b4/EGNOS_map.svg)
The European Geostationary Navigation Overlay Service (EGNOS) is a
satellite-based augmentation system
Augmentation of a global navigation satellite system (GNSS) is a method of improving the navigation system's attributes, such as precision, reliability, and availability, through the integration of external information into the calculation process. ...
(SBAS) developed by the
European Space Agency
, owners =
, headquarters = Paris, ÃŽle-de-France, France
, coordinates =
, spaceport = Guiana Space Centre
, seal = File:ESA emblem seal.png
, seal_size = 130px
, image = Views in the Main Control Room (1205 ...
and
EUROCONTROL
The European Organisation for the Safety of Air Navigation, commonly known as Eurocontrol (stylised ''EUROCONTROL''), is an international organisation working to achieve safe and seamless air traffic management across Europe. Founded in 1960, Eur ...
on behalf of the
European Commission
The European Commission (EC) is the executive of the European Union (EU). It operates as a cabinet government, with 27 members of the Commission (informally known as "Commissioners") headed by a President. It includes an administrative body o ...
. Currently, it supplements the
GPS
The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t ...
by reporting on the reliability and accuracy of their positioning data and sending out corrections. The system will supplement
Galileo
Galileo di Vincenzo Bonaiuti de' Galilei (15 February 1564 – 8 January 1642) was an Italian astronomer, physicist and engineer, sometimes described as a polymath. Commonly referred to as Galileo, his name was pronounced (, ). He was ...
in a future version.
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
geostationary satellite
A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitude ...
s. Ground stations determine accuracy data of the satellite navigation systems and transfer it to the geostationary satellites; users may freely obtain this data from those satellites using an EGNOS-enabled receiver, or over the Internet. One main use of the system is in
aviation
Aviation includes the activities surrounding mechanical flight and the aircraft industry. ''Aircraft'' includes fixed-wing and rotary-wing types, morphable wings, wing-less lifting bodies, as well as lighter-than-air craft such as hot air ...
.
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
Wide Area Augmentation System
The Wide Area Augmentation System (WAAS) is an air navigation aid developed by the Federal Aviation Administration to augment the Global Positioning System (GPS), with the goal of improving its accuracy, integrity, and availability. Essential ...
(WAAS), in Russia by the
System for Differential Corrections and Monitoring (SDCM), and in Asia, by Japan's
Multi-functional Satellite Augmentation System Multi-functional Satellite Augmentation System (MTSAT or MSAS) is a Japanese satellite based augmentation system (SBAS), i.e. a satellite navigation system which supports differential GPS (DGPS) to supplement the GPS system by reporting (then impro ...
(MSAS) and India's
GPS-aided GEO augmented navigation
The GPS-aided GEO augmented navigation (GAGAN) is an implementation of a regional satellite-based augmentation system (SBAS) by the Government of India. It is a system to improve the accuracy of a GNSS receiver by providing reference signals. Th ...
(GAGAN).
Galileo
Galileo di Vincenzo Bonaiuti de' Galilei (15 February 1564 – 8 January 1642) was an Italian astronomer, physicist and engineer, sometimes described as a polymath. Commonly referred to as Galileo, his name was pronounced (, ). He was ...
and EGNOS budget for the 2021–2027 period is €9 billion
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
The Tour de France () is an annual men's multiple-stage bicycle race primarily held in France, while also occasionally passing through nearby countries. Like the other Grand Tours (the Giro d'Italia and the Vuelta a España), it consists ...
road race.
In 2009, the European Commission announced it had signed a contract with the company
European Satellite Services Provider
European, or Europeans, or Europeneans, may refer to:
In general
* ''European'', an adjective referring to something of, from, or related to Europe
** Ethnic groups in Europe
** Demographics of Europe
** European cuisine, the cuisines of Europe ...
to run EGNOS. The official start of operations was announced by the European Commission on 1 October 2009. The system was certified for use in safety of life applications in March 2011.
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.
The European Commission 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) 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.
Satellites and SISNeT
![Inmarsat-3](https://upload.wikimedia.org/wikipedia/commons/3/3a/Inmarsat-3.gif)
Similar to
WAAS
The Wide Area Augmentation System (WAAS) is an air navigation aid developed by the Federal Aviation Administration to augment the Global Positioning System (GPS), with the goal of improving its accuracy, integrity, and availability. Essentia ...
, EGNOS is mostly designed for
aviation
Aviation includes the activities surrounding mechanical flight and the aircraft industry. ''Aircraft'' includes fixed-wing and rotary-wing types, morphable wings, wing-less lifting bodies, as well as lighter-than-air craft such as hot air ...
users who enjoy unperturbed reception of direct signals from
geostationary satellite
A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitude ...
s up to very high
latitude
In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north pol ...
s. The use of EGNOS on the ground, especially in urban areas, is limited due to relatively low
elevation
The elevation of a geographic location is its height above or below a fixed reference point, most commonly a reference geoid, a mathematical model of the Earth's sea level as an equipotential gravitational surface (see Geodetic datum § Vert ...
of
geostationary satellite
A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitude ...
s: about 30° above
horizon
The horizon is the apparent line that separates the surface of a celestial body from its sky when viewed from the perspective of an observer on or near the surface of the relevant body. This line divides all viewing directions based on whether i ...
in central
Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...
and much less in the North of Europe. To address this problem,
ESA
, owners =
, headquarters = Paris, ÃŽle-de-France, France
, coordinates =
, spaceport = Guiana Space Centre
, seal = File:ESA emblem seal.png
, seal_size = 130px
, image = Views in the Main Control Room (120 ...
released in 2002 SISNeT, an
Internet
The Internet (or internet) is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a '' network of networks'' that consists of private, pub ...
service designed for continuous delivery of EGNOS signals to ground users. The first experimental SISNeT receiver was created by the
Finnish Geodetic Institute
The Finnish Geospatial Research Institute ( fi, Paikkatietokeskus), formerly Finnish Geodetic Institute (FGI, fi, Geodeettinen laitos, sv, Geodetiska institutet) is a research institute in Finland specializing in geodesy and geospatial informati ...
. The commercial SISNeT receivers have been developed by
Septentrio
Septentrio N.V. is a designer and manufacturer of high-end multi-frequency GNSS receivers. Its main target is to provide GNSS receiver boards and modules for further system integration by Original Equipment Manufacturers (OEMs). Septentrio's co ...
. PRN #136 was placed into the Operational Platform from 23/08/2018 at 10:00 UTC and PRN #120 was placed into Test Platform from 30/08/2018 at 13:00 UTC.
Services
* Open Service (OS): It improves positioning accuracy by correcting error sources affecting
GNSS
A satellite navigation or satnav system is a system that uses satellites to provide autonomous geo-spatial positioning. It allows satellite navigation devices to determine their location (longitude, latitude, and altitude/elevation) to high pre ...
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
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...
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.
* 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.
Architecture
![EGNOS RIMS BRN](https://upload.wikimedia.org/wikipedia/commons/e/e8/EGNOS_RIMS_BRN.jpg)
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).
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.
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.
References
External links
European Commission information on EGNOSWebsite of the EGNOS operator ESSP SaSEGNOS Operations User SupportESA information on EGNOS*
ttps://www.egnos-pro.esa.int/index.html European Space Agency information on EGNOS for ProfessionalsLearning EGNOSESESA - EGNOS Service Extension to South Africa* Usman A Zahidi, "EGNOS enabled GPS Software Receiver" Report Page
Navipedia information on EGNOS€”Wiki initiated by the European Space Agency
{{Use British English, date=January 2014
European Space Agency programmes
Global Positioning System
Galileo (satellite navigation)
Satellite-based augmentation systems