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The [[GALILEO General Introduction|GALILEO ]]  System is an independent, global, European-controlled, satellite-based navigation system that aims at providing a number of guaranteed services to users equipped with Galileo-compatible receivers. The definition of the [[GALILEO General Introduction|GALILEO ]] Services is based on a comprehensive review of user needs and market analysis. The Galileo mission and services was elaborated during the initial definition phase in consultation with user communities and the Member States and evolve to the services currently provided and described in further paragraphs from this article.
The Galileo is a space-based global navigation satellite system (GNSS) that provides reliable positioning, navigation, and timing services to users on a continuous worldwide basis freely available to all. Galileo receivers compute their position in the [[Galileo Reference Frame|Galileo Reference System]] using satellite technology and based on [[An intuitive approach to the GNSS positioning|triangulation principles]].
 
List of bullets:
*Bullet 1
** Bullet 1.1
*Bullet 2
* Bullet with ''italics''
* Bullet with '''bold'''
* Bullet with '''''bold italics'''''
 
Numbered list:
#Bullet 1
 
 
 
==This is a new section==
[[File:Galileo_Art.png‎‎|400px|Galileo Constelation (artistic interpretation)|left|thumb]]
 
Example of link to article inside Navipedia [[GALILEO Public Regulated Service|Public Regulated Service]].
 
This is an example to cite a reference.<ref>[http://www.esa.int/esaMI/ESA_Publications/SEMNMPN0LYE_0.html EGNOS − The European Geostationary Navigation Overlay] System − A Cornerstone of Galileo (ESA SP-1303)</ref>
 
This is an example to cite a reference.<ref name="Name ref1"/>
 
This is link [http://www.gmv.com to the company GMV], where we both work.
 
This is an example to cite a reference.<ref name="Name ref1">[http://www.esa.int/esaMI/ESA_Publications/SEMNMPN0LYE_0.html EGNOS − The European Geostationary Navigation Overlay System − A Cornerstone of Galileo (ESA SP-1303)]</ref>
 
 
===This is a new subsection===


==Introduction==
==Introduction==
There are some services provided autonomously by Galileo and other services resulting from the combined use of Galileo and other systems. This leads to the classification of the Galileo services into four categories:<ref name="GALHLD"> Galileo Mission High Level Definition, v7.1.</ref>


[[File:Galileo_Art.png‎‎|400px|Galileo Constelation (artistic interpretation)|left|thumb]]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.<ref name="CR Galileo">Council Resolution of 19 July 1999 on the involvement of Europe in a new generation of satellite navigation services -Galileo- Definition phase [http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:C:1999:221:0001:0003:EN:PDF (1999/C 221/01)]</ref> While providing autonomous navigation and positioning services, the system established under the Galileo program will at the same time be interoperable with other GNSS systems such as [[GPS]] and [[GLONASS]]. The system will consist of 30 satellites, to be deployed in a staggered approach, and the associated ground infrastructure.<ref>[http://www.esa.int/esaNA/galileo.html ESA Galileo web page]</ref>
# GALILEO satellite-only services: These services are provided worldwide and independently from other systems by combining the signals broadcast by the Galileo satellites. There is a wide range of possible applications with different operational requirements that have been grouped around the following reference services<ref name="Galileo Services GSA>[https://www.gsa.europa.eu/galileo/services Galileo services in GSA website]</ref>:
 
#* [[Galileo Open Service (OS)]].
A user will be able to take a position with the same receiver from any of the satellites in any combination. By offering dual frequencies as standard, Galileo will deliver real-time positioning accuracy down to the meter range.  It will guarantee availability of the service under all but the most extreme circumstances and will inform users within seconds of a failure of any satellite. This will make it suitable for applications where safety is crucial, such as running trains, guiding cars and landing aircraft.
#* [[Galileo High Accuracy Service (HAS)]], previously known as Galileo Commercial Service (CS).
 
#* [[Galileo  Public Regulated Service (PRS)]].
The first experimental satellites, GIOVE-A (launched on 2005) and GIOVE-B (launched on 2008) have already tested critical technologies and secured the Galileo frequencies within the [[Wikipedia:International Telecommunications Union|International Telecommunications Union]]. Thereafter, four operational satellites - the basic minimum for satellite navigation in principle - will be launched in 2011 to validate the Galileo concept with both segments: space and related ground infrastructure.
#* [[Galileo Search and Rescue Service|Galileo Support to Search and Rescue Service (SAR)]].
 
#:Initially, Galileo foresaw a [[Galileo Safety of Life (SoL)|Safety of Life (SoL) service]], which is currently being re-profiled, one of the solutions under assessment being [[ARAIM|ARAIM]].
Based on the award of the contracts for the first order of satellites, the launch services, the system support services and the operations, the [[Wikipedia:European Commission|European Commission]] announced the Initial Operational Capability (IOC) with three initial services to be provided in 2014/2015: an initial [[GALILEO Open Service|Open Service]], an initial [[GALILEO Public Regulated Service|Public Regulated Service]] and an initial [[GALILEO Search and Rescue Service|Search and Rescue Service]].<ref>Commission awards major contracts to make Galileo operational early 2014,  [http://europa.eu/rapid/pressReleasesAction.do?reference=IP/10/7 IP/10/7], Brussels, 7 January 2010.</ref> At this stage, accuracy and availability will not yet have reached their optimum level, the [[GALILEO Safety-of-Life Service|Safety-of-Life Service]] and the [[GALILEO Commercial Service| Commercial Service]] will be tested and will be provided as the system reaches full operational capability with the 30 satellites<ref name="Mid-term review">[http://ec.europa.eu/enterprise/newsroom/cf/_getdocument.cfm?doc_id=6321 Mid-term review of the European satellite radio navigation programmes]</ref>
# [[GNSS Augmentation| GALILEO locally assisted services]]: The Galileo satellite-only services can be enhanced on a local basis through a combination of local elements. The result is the provision of local services.
Galileo will ensure Europe's independence in a sector that has become critical for its economy and the well-being of its citizens.
# [[EGNOS Services|EGNOS services]]: [[EGNOS General Introduction|EGNOS ]], the European regional satellite-based augmentation system (SBAS), will provide,in future evolutions, augmentation information to both GPS and Galileo constellations, to improve the performance of those global navigation systems. EGNOS v3 will provide new capabilities to support the augmentation of a second GPS signal (L5) and of the Galileo signals E1-E5. <ref name="EGNOS V3>[https://www.gsa.europa.eu/newsroom/news/airbus-awarded-egnos-v3-contract EGNOS V3 Contract in GSA website]</ref>.
 
# Galileo combined services: All the above-mentioned services can be combined with services provided by other navigation or communication systems. This possibility will improve the GNSS services availability at user level and open the door to a wide range of applications. The result will be the provision of combined services.
[[GPS]] (US), [[GLONASS]] (Russia) and the other regional systems developed by Japan and China are military systems under military control – indeed they provide a civil service but that civil service could be either switched off or made less precise when desired e.g. in case of conflict. The world has become so dependent on services provided by satellite navigation in our daily lives that should a service be reduced or switched off, the potential disruption to business, banking, transport, aviation, communication, etc., to name but a few, would be very costly (e.g. in terms of revenues for business, road safety, etc.).
 
The combination of Galileo and [[GPS]] signals ([[Principlies of Interoperability amongs GNSS|inter-operability]]) in dual receivers will open the door to new [[GNSS Application|GNSS applications]] that require a higher level of precision than currently available with [[GPS]] alone. From most locations, six to eight Galileo satellites will be visible which, in combination with [[GPS]] signals, will allow positions to be determined up to within a few centimetres. Examples of these applications are: guide the blind, increase the success rate of rescue operations in the mountains, monitor the whereabouts of people suffering from Alzheimer Disease, etc.
 
In addition, Galileo will improve the overall [[Availability|availability]] and coverage of GNSS signals. For example, the higher number of satellites will improve the [[Availability|availability]] of the signals in high rise cities where buildings can obstruct signals from satellites that are low on the horizon.
 
With Galileo, Europe will be able to exploit the opportunities provided by satellite navigation to the full extent. [[GNSS Receivers|GNSS receiver]] and equipment manufacturers, application providers and service operators will benefit from novel business opportunities.<ref name="EC GAL web">[http://ec.europa.eu/enterprise/policies/satnav/galileo/index_en.htm EC Galileo website]</ref>
 
==History and Development==
 
As far back as the 1990s, the [[Wikipedia:European Union|European Union]] saw the need for Europe to have its own global satellite navigation system.<ref name="CR Galileo"/> The conclusion to build one was taken in similar spirit to decisions in the 1970s to embark on other well-known European endeavours, such as the [http://www.esa.int/esaMI/Launchers_Home/index.html Ariane] launcher and the [[Wikipedia:Airbus|Airbus]]. The [[Wikipedia:European Commission|European Commission]] and [http://www.esa.int/ European Space Agency] joined forces to build Galileo, an independent European system under civilian control.
 
The definition phase and the development and In-Orbit Validation phase of the Galileo program were carried out by the [http://www.esa.int/ European Space Agency (ESA)] and co-funded by ESA and the [[Wikipedia:European Union|European Union]]. The Full Operational Capability phase of the Galileo program is fully funded by the [[Wikipedia:European Union|European Union]] and managed by the [[Wikipedia:European Commission|European Commission]]. The [[Wikipedia:European Commission|Commission]] and [http://www.esa.int/ ESA] have signed a delegation agreement by which [http://www.esa.int/ ESA] acts as design and procurement agent on behalf of the [[Wikipedia:European Commission|Commission]].
 
The Galileo program has been structured according to three main phases:<ref name="EC GAL web"/>
* In-Orbit Validation (IOV) phase:
:The IOV phase consists 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 provide an early experimental signal-in-space allowing securing the frequency spectrum required for Galileo in accordance with WRC RNSS allocations. The launch of the first two operational satellites is scheduled for end of 2011.
 
* Initial Operational Capability (IOC) phase:
:The IOC stage will be the partial commissioning of the ground and space infrastructure as from 2014-2015 and the provision of the [[GALILEO Open Service|open service]], the [[GALILEO Search and Rescue Service|search and rescue service]] and the [[GALILEO Public Regulated Service|PRS]]. While this first stage will be sufficient to test the services it should nonetheless be as short as possible, because it will not allow the system's full potential to be exploited and will not meet the requirements of all users.
 
* 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) should be achieved in 2019-2020, in a staggered approach from the IOC phase. It might change, depending on availability of financing, technical problems and industrial performance.
 
 
==GALILEO Services==
The Galileo mission and services have been elaborated during the initial definition phase in consultation with user communities and the Member States. The services that are planned to be provided by Galileo are the following:<ref name="Mid-term review"/>
* [[GALILEO Open Service|Open Service (OS)]]: With positioning accurate to one metre, the freely accessible Open Service targets the mass market and is intended for motor vehicle navigation and location-based mobile telephone services. Free to the user, it provides positioning and synchronization information intended for high-volume satellite radio navigation applications;
* [[GALILEO Safety-of-Life Service|Safety-of-Life Service (SoL)]]: The Safety of Life service will automatically inform users within seconds of a failure of any satellite or similar problem affecting performance. This service will be made available for [[Criticality of GNSS Applications#Categorization of the Criticality of GNSS Applications|safety-critical applications]] such as running trains, guiding cars, navigation and aviation. This service also fulfils the requirements of certain sectors for [[Continuity|continuity]], [[Availability|availability]] and [[Accuracy|accuracy]] and includes an [[Integrity|integrity]] function alerting the user of any failure in the system;
* [[GALILEO Commercial Service|Commercial Service (CS)]]: Encrypted and accurate to the nearest centimetre, the Commercial Service allows for development of applications for professional or commercial use owing to improved performance and data with greater added value than that obtained through the open service;
* [[GALILEO Public Regulated Service|Public Regulated Service (PRS)]]: The Public Regulated Service is restricted to government-authorised users, for sensitive applications which require a high level of service continuity. It will be encrypted and designed to be more robust, with anti-jamming mechanisms and reliable problem detection. This service is intended for security and strategic infrastructure (e.g. energy, telecommunications and finance);
* [[GALILEO Search and Rescue Service|Search and Rescue Service (SAR)]]: Galileo's worldwide search and rescue service will help to forward distress signals to a rescue coordination centre by detecting emergency signals transmitted by beacons and relaying messages to them.
 
==[[GALILEO Architecture]]==
 
[[File:Galileo Space Segment.jpg|250px|Galileo Space Segment|right|thumb]]To ensure these Galileo services, a specific architecture is deployed.  The Galileo system is divided into three major segments: [[GALILEO Space Segment|Space Segment]], [[GALILEO Ground Segment|Control Segment]] and [[GALILEO User Segment|User Segment]]. For details see [[GALILEO Architecture|Galileo Architecture]].
 
The main functions of the [[GALILEO Space Segment|Galileo Space Segment]] are to generate and transmit code and carrier phase signals with a specific [[GALILEO Signal Structure|Galileo signal structure]], and to store and retransmit the navigation message sent by the [[GALILEO Ground Segment|Control Segment]]. These transmissions are controlled by highly stable atomic clocks on board the satellites.
 
When Galileo is fully operational, there will be 30 satellites in Medium Earth Orbit (MEO) at an altitude of 23,222 kilometres. The satellites will occupy each of three orbital planes inclined at an angle of 56° to the equator. The satellites will be spread evenly around each plane and will take about 14 hours to orbit the Earth. One satellite in each plane will be a spare; on stand-by should any operational satellite fail.
 
[[File:Galileo Ground Segment.png|300px|Galileo Ground Segment|left|thumb]]The [[GALILEO Ground Segment|Galileo Control Segment]] (also referred to as Ground Segment) is the responsible for the proper operation of the GNSS system. Its basic functions are:
* To control and maintain the status and configuration of the satellite constellation.
* To predict ephemeris and satellite clock evolution.
* To keep the corresponding GNSS time scale (through atomic clocks).
* To update the navigation messages for all the satellites.
 
The [[GALILEO Ground Segment|Galileo Ground Segment]] constitutes the major system element controlling the entire constellation, the navigation system facilities and the dissemination services. It is composed of two Ground Control Centres (GCC), five Telemetry, Tracking and Control (TT&C) stations, nine Mission Uplink Stations (ULS), and about fourteen Galileo Sensor Stations (GSS).
 
The  [[GALILEO User Segment|Galileo user segment]] is composed by [[GALILEO Receivers|Galileo receivers]]. Their main function is to receive Galileo signals, determine pseudoranges (and other observables), and solve the navigation equations
in order to obtain their coordinates and provide a very accurate time.
 
 
==Galileo Signal Characteristics==
 
The Galileo navigation Signals are transmitted in the four frequency bands indicated in next figure. These four frequency bands are the E5a, E5b, E6 and E1 bands. They provide a wide bandwidth for the transmission of the Galileo Signals.<ref>[http://ec.europa.eu/enterprise/policies/satnav/galileo/files/galileo-os-sis-icd-issue1-revision1_en.pdf Galileo OS SIS ICD Issue 1 Revision 1 September 2010e]</ref>
 
[[File:Galileo Frequency Plan.png|571px|Galileo Frequency Plan|none|thumb]]


The Galileo frequency bands have been selected in the allocated spectrum for Radio Navigation Satellite Services (RNSS). In addition to that, E5a, E5b and E1 bands are included in the allocated spectrum for Aeronautical Radio Navigation Services (ARNS), employed by Civil-Aviation users, and allowing dedicated safety-critical applications. The names of the Galileo signals are the same as the corresponding carrier frequencies. Note that E5a and E5b signals are part of the E5 bandwidth.
More information related to EGNOS and Galileo locally assisted services could be found in their related articles in Navipedia.


==[[GALILEO Performances]]==
==GALILEO satellite-only services==


The Galileo [[GNSS Performances|performances]] are different for each service. For the [[GALILEO Open Service|Galileo Open Service (OS)]] no specific requirements of [[Integrity|integrity]] are applicable. The [[GNSS Performances|performances]] for horizontal positioning [[Accuracy|accuracy]] at 95% for a dual-frequency receiver are 4 m (8 m for vertical [[Accuracy|accuracy]]), with an [[Availability|availability]] of the service of 99%.
[[File:Galileo_Art.png‎‎|300px|Galileo Constellation (artistic interpretation)|thumb]]


In the case of the [[GALILEO Safety-of-Life Service|Galileo Safety of Life (SoL)]] and the [[GALILEO Public Regulated Service|Galileo Public Regulated Service (PRS)]], the [[GNSS Performances|performance]] requirements include horizontal and vertical [[Accuracy|accuracy]], [[Integrity|integrity]], [[Continuity|continuity]] and time to alert for different service levels. The [[Availability|availability]] of the service should be 99.5% for both services.  
The following Galileo satellite-only services will be provided worldwide and independently from other systems by combining Galileo signals-in-space <ref name="Galileo Services GSA>[https://www.gsa.europa.eu/galileo/services Galileo services in GSA website]</ref> when it achieves its Full Operational Capability:
* [[Galileo Open Service (OS)]] results from a combination of open signals, free of user charge, and provides position and timing performance. This service will include authentication capabilities in the future through [[Galileo Open Service Navigation Message Authentication | Galileo OS-NMA]];
* [[Galileo High Accuracy Service (HAS)]] A service complementing the OS by providing an additional navigation signal and added-value services in a different frequency band. The HAS signal can be encrypted in order to control the access to the Galileo HAS services.
* [[Galileo Public Regulated Service (PRS)]] provides position and timing to specific users requiring a high continuity of service, with controlled access. The Public Regulated Service is restricted to government-authorized users, for sensitive applications which require a high level of service continuity. This service is intended for security and strategic infrastructure (e.g. energy, telecommunications and finance);
* [[Galileo Search and Rescue Service|Galileo Support to Search and Rescue Service (SAR)]] represents the contribution of Europe to the international [http://www.cospas-sarsat.int COSPAS-SARSAT] co-operative effort on humanitarian Search and Rescue activities. Galileo is to play an important part of the Medium Earth Orbit Search and Rescue system (MEOSAR). Galileo satellites are able to pick up signals from emergency beacons carried on ships, planes or persons and ultimately send these back to national rescue centers. From this, a rescue center can know the precise location of an accident. At least one Galileo satellite will be in view of any point on Earth so near real-time distress alert is possible. In some cases, feedback could be sent back to a beacon, something which is only made possible by Galileo.


See the article [[GALILEO Performances|Galileo Performances]] for further information.
The Galileo program was structured according to three main phases:<ref name="Mid-term review">[http://europa.eu/rapid/press-release_MEMO-11-26_en.htm Mid-term review of the European satellite radio navigation programmes]</ref><ref name="EC GAL Prog">[http://ec.europa.eu/growth/sectors/space/galileo_en European Commission (EC) - Galileo Programme]</ref> [[GALILEO_Future_and_Evolutions|In-Orbit Validation (IOV), Initial Operational Capability (IOC) and Full Operational Capability (FOC)]]. Galileo Initial Services <ref name="Galileo Initial Services in GSA website">[https://ec.europa.eu/commission/presscorner/detail/en/IP_16_4366 Galileo Initial Services in GSA website]</ref> are the first step towards the Full Operational Capability. The initial services offered by Galileo are Open Service (OS), the Public Regulated Service (PRS) and the Search and Rescue (SAR) service. The Return Link Capability of the Search and Rescue service was declared in January 2020. <ref name= "Return link"> [https://www.gsa.europa.eu/newsroom/news/galileo-return-link-service-declared-european-space-conference Galileo Return Link Service Declaration in GSA website]</ref> The performance of Galileo will gradually improve as additional services are added to the constellation.


For  more information about performances of each service, see the article [[GALILEO Performances|Galileo Performances]].


==Notes==
<references group="footnotes"/>
==References==
==References==
<references/>
<references/>


[[Category:GALILEO]]
[[Category:GALILEO|Services]]

Latest revision as of 11:17, 29 January 2021


GALILEOGALILEO
Title Galileo Services
Edited by GMV
Level Basic
Year of Publication 2011
Logo GMV.png

The GALILEO System is an independent, global, European-controlled, satellite-based navigation system that aims at providing a number of guaranteed services to users equipped with Galileo-compatible receivers. The definition of the GALILEO Services is based on a comprehensive review of user needs and market analysis. The Galileo mission and services was elaborated during the initial definition phase in consultation with user communities and the Member States and evolve to the services currently provided and described in further paragraphs from this article.

Introduction

There are some services provided autonomously by Galileo and other services resulting from the combined use of Galileo and other systems. This leads to the classification of the Galileo services into four categories:[1]

  1. GALILEO satellite-only services: These services are provided worldwide and independently from other systems by combining the signals broadcast by the Galileo satellites. There is a wide range of possible applications with different operational requirements that have been grouped around the following reference services[2]:
    Initially, Galileo foresaw a Safety of Life (SoL) service, which is currently being re-profiled, one of the solutions under assessment being ARAIM.
  2. GALILEO locally assisted services: The Galileo satellite-only services can be enhanced on a local basis through a combination of local elements. The result is the provision of local services.
  3. EGNOS services: EGNOS , the European regional satellite-based augmentation system (SBAS), will provide,in future evolutions, augmentation information to both GPS and Galileo constellations, to improve the performance of those global navigation systems. EGNOS v3 will provide new capabilities to support the augmentation of a second GPS signal (L5) and of the Galileo signals E1-E5. [3].
  4. Galileo combined services: All the above-mentioned services can be combined with services provided by other navigation or communication systems. This possibility will improve the GNSS services availability at user level and open the door to a wide range of applications. The result will be the provision of combined services.

More information related to EGNOS and Galileo locally assisted services could be found in their related articles in Navipedia.

GALILEO satellite-only services

Galileo Constellation (artistic interpretation)

The following Galileo satellite-only services will be provided worldwide and independently from other systems by combining Galileo signals-in-space [2] when it achieves its Full Operational Capability:

  • Galileo Open Service (OS) results from a combination of open signals, free of user charge, and provides position and timing performance. This service will include authentication capabilities in the future through Galileo OS-NMA;
  • Galileo High Accuracy Service (HAS) A service complementing the OS by providing an additional navigation signal and added-value services in a different frequency band. The HAS signal can be encrypted in order to control the access to the Galileo HAS services.
  • Galileo Public Regulated Service (PRS) provides position and timing to specific users requiring a high continuity of service, with controlled access. The Public Regulated Service is restricted to government-authorized users, for sensitive applications which require a high level of service continuity. This service is intended for security and strategic infrastructure (e.g. energy, telecommunications and finance);
  • Galileo Support to Search and Rescue Service (SAR) represents the contribution of Europe to the international COSPAS-SARSAT co-operative effort on humanitarian Search and Rescue activities. Galileo is to play an important part of the Medium Earth Orbit Search and Rescue system (MEOSAR). Galileo satellites are able to pick up signals from emergency beacons carried on ships, planes or persons and ultimately send these back to national rescue centers. From this, a rescue center can know the precise location of an accident. At least one Galileo satellite will be in view of any point on Earth so near real-time distress alert is possible. In some cases, feedback could be sent back to a beacon, something which is only made possible by Galileo.

The Galileo program was structured according to three main phases:[4][5] In-Orbit Validation (IOV), Initial Operational Capability (IOC) and Full Operational Capability (FOC). Galileo Initial Services [6] are the first step towards the Full Operational Capability. The initial services offered by Galileo are Open Service (OS), the Public Regulated Service (PRS) and the Search and Rescue (SAR) service. The Return Link Capability of the Search and Rescue service was declared in January 2020. [7] The performance of Galileo will gradually improve as additional services are added to the constellation.

For more information about performances of each service, see the article Galileo Performances.

References