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Galileo positioning system

Galileo positioning system

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Galileo is a global navigation satellite system
Global Navigation Satellite System
A satellite navigation or SAT NAV system is a system of satellites that provide autonomous geo-spatial positioning with global coverage. It allows small electronic receivers to determine their location to within a few metres using time signals transmitted along a line-of-sight by radio from...

 (GNSS) currently being built by the European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

 (EU) and 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...

 (ESA). The €20 billion project is named after the famous Italian astronomer Galileo Galilei
Galileo Galilei
Galileo Galilei , was an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations and support for Copernicanism...

. One of the political aims of Galileo is to provide a high-precision positioning system upon which European nations can rely, independently from the Russian 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 US GPS systems which can be disabled for commercial users in times of war or conflict.

When in operation, it will use two ground operations centres, near Munich
Munich
Munich The city's motto is "" . Before 2006, it was "Weltstadt mit Herz" . Its native name, , is derived from the Old High German Munichen, meaning "by the monks' place". The city's name derives from the monks of the Benedictine order who founded the city; hence the monk depicted on the city's coat...

, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 and in Fucino
Fucine Lake
The Fucine Lake was a large lake in central Italy, stretching from Avezzano in the northwest to Ortuccio in the southeast, and touching Trasacco in the southwest. It was drained in 1875.-Roman drainage:...

, Italy
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

. The system was initially expected to become operational by 2012, but that date has been repeatedly moved back. As of 2011, initial service is expected around 2014 and completion by 2019.

Galileo will be a free service. It is intended to provide horizontal and vertical positions measurements with metre-class precision, and better positioning services at 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 than GPS and GLONASS. As a further feature, Galileo will provide a global Search and Rescue (SAR) function. To do so, each satellite will be equipped with a transponder, which is able to transfer the distress signals from the user's transmitter to the Rescue Co-ordination Centre, which will then initiate the rescue operation. At the same time, the system will provide a signal to the user, informing them that their situation has been detected and that help is on the way. This latter feature is new and is considered a major upgrade compared to the existing GPS and GLONASS navigation systems, which do not provide feedback to the user. The use of basic (low-precision) Galileo services will be free and open to everyone. The high-precision capabilities will be available for paying commercial users and for military use.

The first satellites will bear the names of eleven-year-old Thijs from Belgium
Belgium
Belgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...

 and nine-year-old Natalia from Bulgaria
Bulgaria
Bulgaria , officially the Republic of Bulgaria , is a parliamentary democracy within a unitary constitutional republic in Southeast Europe. The country borders Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, as well as the Black Sea to the east...

 who are the first winners of the European Comission's Galileo children's drawing competition. Competition winners from the remaining 25 Member States
Member State of the European Union
A member state of the European Union is a state that is party to treaties of the European Union and has thereby undertaken the privileges and obligations that EU membership entails. Unlike membership of an international organisation, being an EU member state places a country under binding laws in...

 will name the satellites which will be launched until 2019.

History


In 1999, the different concepts (from Germany, France, Italy and the United Kingdom) for Galileo were compared and reduced to one by a joint team of engineers from all four countries. The first stage of the Galileo programme was agreed upon officially on 26 May 2003 by the European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

 and 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...

. The system is intended primarily for civilian use, unlike the United States system, which the U.S. military runs and uses on a primary basis. The U.S. reserves the right to limit the signal strength or precision of GPS
Global Positioning System
The Global Positioning System is a space-based global navigation satellite system that provides location and time information in all weather, anywhere on or near the Earth, where there is an unobstructed line of sight to four or more GPS satellites...

, or to shut down public GPS access completely, so that only the U.S. military and its allies would be able to use it in time of conflict. Until 2000, the precision of the signal available to non-U.S.-military users was limited (due to a timing pulse distortion process known as selective availability). The European system will only be subject to shutdown for military purposes in extreme circumstances. It will be available at its full precision to both civil
Civilian
A civilian under international humanitarian law is a person who is not a member of his or her country's armed forces or other militia. Civilians are distinct from combatants. They are afforded a degree of legal protection from the effects of war and military occupation...

 and military
Military
A military is an organization authorized by its greater society to use lethal force, usually including use of weapons, in defending its country by combating actual or perceived threats. The military may have additional functions of use to its greater society, such as advancing a political agenda e.g...

 users.

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....

 had some difficulty funding the project's next stage, after several allegedly "per annum" sales projection graphs for the project were exposed in November 2001 as "cumulative" projections (which for each year projected, necessarily included all previous years of sales). The attention that was brought to this multi-billion euro exponentially growing error in sales forecasts resulted in a general awareness in the Commission and elsewhere that the program did not have near the return on investment that had been presented to the investors and decision-makers up until that point. Additionally, following the September 11, 2001 attacks
September 11, 2001 attacks
The September 11 attacks The September 11 attacks The September 11 attacks (also referred to as September 11, September 11th or 9/119/11 is pronounced "nine eleven". The slash is not part of the pronunciation...

, the United States Government wrote to the European Union opposing the project, arguing that it would end the ability of the United States to shut down satellite navigation in times of military operations. On 17 January 2002 a spokesman for the project stated that, as a result of U.S. pressure and economic difficulties, "Galileo is almost dead." A few months later, however, the situation changed dramatically. European Union member states decided it was important to have a satellite-based positioning and timing infrastructure that the US could not easily turn off in times of political conflict.

The European Union and the European Space Agency agreed in March 2002 to fund the project, pending a review in 2003 (which was finalised on 26 May 2003). The starting cost for the period ending in 2005 is estimated at
Euro
The euro is the official currency of the eurozone: 17 of the 27 member states of the European Union. It is also the currency used by the Institutions of the European Union. The eurozone consists of Austria, Belgium, Cyprus, Estonia, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg,...

1.1 billion. The required satellites (the planned number is 30) will be launched throughout the period 2011–2014 and the system will be up and running and under civilian control from 2019. The final cost is estimated at €3 billion, including the infrastructure on Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...

, which is to be constructed in the years 2006 and 2007. The plan was for private companies and investors to invest at least two-thirds of the cost of implementation, with the EU and ESA dividing the remaining cost. An encrypted higher-bandwidth Commercial Service with improved precision would be available at an extra cost, with the base Open Service freely available to anyone with a Galileo-compatible receiver
Receiver (radio)
A radio receiver converts signals from a radio antenna to a usable form. It uses electronic filters to separate a wanted radio frequency signal from all other signals, the electronic amplifier increases the level suitable for further processing, and finally recovers the desired information through...

. Costs for the project have run 50% over initial estimates.

In June 2004, in a signed agreement with the United States, the European Union agreed to switch to a modulation known as BOC(1,1) (Binary Offset Carrier 1.1) allowing the coexistence of both GPS and Galileo, and the future combined use of both systems. The European Union also agreed to address the "mutual concerns related to the protection of allied and U.S. national security capabilities."

The first experimental satellite, GIOVE-A, was launched in 2005 and was followed by a second test satellite, GIOVE-B, launched in 2008. The first four operational satellites for navigation will be launched in 2011 and once this In-Orbit Validation (IOV) phase has been completed, additional satellites will be launched. On 30 November 2007 the 27 EU transportation ministers involved reached an agreement that it should be operational by 2013, but later press releases suggest it was delayed to 2014.

Early 2007, the EU had yet to decide how to pay for the system and the project was said to be "in deep crisis" due to lack of more public funds. German Transport Minister Wolfgang Tiefensee was particularly doubtful about the consortium's ability to end the infighting at a time when only one testbed satellite had been successfully launched.

Although a decision was yet to be reached, on 13 July 2007 EU countries discussed cutting €548m ($755m, £370m) from the union's competitiveness budget for the following year and shifting some of that cash to other parts of the financing pot, a move that could meet part of the cost of the union's Galileo satellite navigation system. European Union research and development projects could be scrapped to overcome a funding shortfall.

In November 2007, it was agreed to reallocate funds from the EU's agriculture and administration budgets and to soften the tendering process in order to invite more EU companies.

In April 2008, the EU transport ministers approved the Galileo Implementation Regulation. This allowed the €3.4bn to be released from the EU's agriculture and administration budgets. This will allow the issuing of contracts to start construction of the ground station and the satellites.

In June 2009, the European Court of Auditors
European Court of Auditors
The Court of Auditors is the fifth institution of the European Union . It was established in 1975 in Luxembourg to audit the accounts of EU institutions...

 published a report, pointing out governance issues, substantial delays and budget overruns that led to project stalling in 2007, leading to further delays and failures.

In October 2009, 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....

 cut the number of satellites from 28 to 22, with plans to order the remaining six at a later time. It also announced that the first OS, PRS and SoL signal will be available in 2013 and the CS and SOL sometime later. Current budget for 2006–2013 period planned for €3.4 billion was also considered as insufficient. The think tank Open Europe has estimated the total cost of Galileo from start to completion, and then running it over a 20 year period, at a €22.2 billion, which will be borne entirely by taxpayers. Under the original estimates (from 2000) this cost would have been €7.7 billion, of which only €2.6 billion was to be borne by taxpayers and the rest by private investors.

In November 2009, a ground station for Galileo was inaugurated near Kourou
Kourou
Kourou is a commune in French Guiana, an overseas region and department of France located in South America.Kourou is the location of the Guiana Space Centre, France and ESA's main spaceport.-Geography:...

 (French Guiana
French Guiana
French Guiana is an overseas region of France, consisting of a single overseas department located on the northern Atlantic coast of South America. It has borders with two nations, Brazil to the east and south, and Suriname to the west...

).

The launch of the first four in-orbit validation (IOV) satellites was planned for the 2nd half of 2011, while the launch of full operational capability (FOC) satellites is planned to start in late 2012.

As of March 2010 it was verified that the budget for Galileo would only be available to provide the 4 IOV and 14 FOC satellites by 2014, with no funds currently committed to bring the constellation above this 60% capacity. Paul Verhoef, the then current satellite navigation program manager at the European Commission indicated that this limited funding would have serious consequences commenting at one point "To give you an idea, that would mean that for three weeks in the year you will not have satellite navigation" in reference to the currently proposed 18 vehicle constellation.

In July 2010 the European Commission estimated further delays and additional costs of the project to grow up to €1.5-€1.7 billion and moved the estimated date of completion to 2018. After it's completed, the system will need to be subsidized by governments at €750 million per year. An additional €1.9 billion was planned to be spent bringing the system up to the full complement of 30 satellites (27 operational + 3 active spares).

In December 2010 EU ministers in Brussels have voted Prague
Prague
Prague is the capital and largest city of the Czech Republic. Situated in the north-west of the country on the Vltava river, the city is home to about 1.3 million people, while its metropolitan area is estimated to have a population of over 2.3 million...

 (Czech Republic
Czech Republic
The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....

) as the headquarters of the Galileo project.
In January 2011, infrastructure costs up to 2020 were estimated at €5.3 billion. In that same month, Wikileaks revealed
United States diplomatic cables leak
The United States diplomatic cables leak, widely known as Cablegate, began in February 2010 when WikiLeaks—a non-profit organization that publishes submissions from anonymous whistleblowers—began releasing classified cables that had been sent to the U.S. State Department by 274 of its consulates,...

 the opinion of CEO of German satellite company OHB-System
OHB-System
OHB-System is a medium-sized spaceflight company located in Bremen, northern Germany, which belongs to the OHB-Technology AG. OHB-System is a systems provider in the areas of telematics, space technology, security and satellite services...

, Berry Smutny. He is quoted saying that Galileo "is a stupid idea that primarily serves French interests". The BBC understands 500m euros (£440m) will become available to make the extra purchase, taking Europe's version of GPS from 18 operational satellites in the next few years to 24.

The first two Galileo In-Orbit Validation satellites were launched by Soyuz flown from Guiana Space Centre on October 21, 2011. Two more are scheduled for launch in 2012.

International involvement



In September 2003, China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

 joined the Galileo project. China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

 was to invest €230 million (USD
United States dollar
The United States dollar , also referred to as the American dollar, is the official currency of the United States of America. It is divided into 100 smaller units called cents or pennies....

 302 million, GBP
Pound sterling
The pound sterling , commonly called the pound, is the official currency of the United Kingdom, its Crown Dependencies and the British Overseas Territories of South Georgia and the South Sandwich Islands, British Antarctic Territory and Tristan da Cunha. It is subdivided into 100 pence...

 155 million, CNY
Renminbi
The Renminbi is the official currency of the People's Republic of China . Renminbi is legal tender in mainland China, but not in Hong Kong or Macau. It is issued by the People's Bank of China, the monetary authority of the PRC...

 2.34 billion) in the project over the following years.

In July 2004, Israel
Israel
The State of Israel is a parliamentary republic located in the Middle East, along the eastern shore of the Mediterranean Sea...

 signed an agreement with the EU
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

 to become a partner in the Galileo project.

On 3 June 2005 the EU and Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...

 signed an agreement for Ukraine to join the project, as noted in a press release.

As of November 2005, Morocco
Morocco
Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...

 also joined the programme.

On 12 January 2006, South Korea
South Korea
The Republic of Korea , , is a sovereign state in East Asia, located on the southern portion of the Korean Peninsula. It is neighbored by the People's Republic of China to the west, Japan to the east, North Korea to the north, and the East China Sea and Republic of China to the south...

 joined the programme.

In November 2006, China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

 decided to develop an independent global navigation system: Beidou navigation system
Beidou navigation system
The BeiDou Navigation System or BeiDou Navigation Satellite System is a project by China to develop an independent satellite navigation system...

.
When Galileo was viewed as a private-sector development with public-sector financial participation, European Commission program managers sought Chinese participation in pursuit of Chinese cash in the short term and privileged access to China’s market for positioning and timing applications in the longer term. However, due to security and technology-independence policy from European Commission, China was, in effect, dis-invited from Galileo and without a return of its monetary investment, a decision that was reinforced by China’s move to build its own global system, called Beidou/Compass. At the Munich Satellite Navigation Summit on March 10, a Chinese government official bluntly asked the European Commission why it no longer wanted to work with China, and when China’s cash investment in Galileo would be returned.

On 30 November 2007, the 27 member states of the European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

 unanimously agreed to move forward with the project, with plans for bases in Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 and Italy
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

. Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

 did not approve during the initial vote, but approved it later that day. This greatly improves the viability of the Galileo project: "The EU's executive had previously said that if agreement was not reached by January 2008, the long-troubled project would essentially be dead."

On 3 April 2009, Norway
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...

 too joined the programme pledging €68.9 million toward development costs and allowing its companies to bid for the construction contracts. Norway, while not a member of the EU
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

, is a member of the ESA
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...

.

Tension with the United States


Galileo is intended to be an EU
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

 GNSS civilian system that allows all users access to it. GPS is a US GNSS military system that provides location signals that have high precision to US military users, while also providing less precise location signals to others. The GPS had the capability to block the "civilian" signals while still being able to use the "military" signal (M-band). A primary motivation for the Galileo project was European concern that the US could deny others access to GPS during political disagreements.

Since Galileo was designed to provide the highest possible precision (possibly even greater than GPS) to anyone, the US was concerned that an enemy could use Galileo signals in military strikes against the US and its allies (some weapons like missiles use GNSS systems for guidance). The frequency initially chosen for Galileo would have made it impossible for the US to block the Galileo signals without also interfering with their own GPS signals. The US did not want to lose their GNSS capability with GPS while denying enemies the use of GNSS. Some US officials became especially concerned when Chinese interest in Galileo was reported.

An anonymous European official claimed that the US officials implied they may consider shooting down Galileo satellites in the event of a major conflict in which Galileo was used in attacks against American forces. The EU's stance is that Galileo is a neutral technology, available to all countries and everyone. At first, EU officials did not want to change their original plans for Galileo, but have since reached a compromise, that Galileo was to use a different frequency. This allowed the blocking/jamming of one GNSS system without affecting the other, giving the US a greater advantage in conflicts in which it has the electronic warfare upper hand. However, the frequency difference also makes it possible to jam the GPS without affecting the Galileo.

GPS and Galileo


One of the reasons given for developing Galileo as an independent system was that GPS is widely used worldwide for civilian applications, which until 2000 had universal Selective Availability (SA) enabled (and still bears the possibility of being reenabled). This could intentionally render the locations given via GPS inaccurate. Galileo's proponents argued that civil infrastructure, including aeroplane navigation and landing, should not rely solely upon GPS.

On May 2, 2000, SA was disabled by the then President of the United States Bill Clinton
Bill Clinton
William Jefferson "Bill" Clinton is an American politician who served as the 42nd President of the United States from 1993 to 2001. Inaugurated at age 46, he was the third-youngest president. He took office at the end of the Cold War, and was the first president of the baby boomer generation...

, and in late 2001, the entity managing the GPS confirmed that they never intend to enable selective availability again. Though Selective Availability still exists, on 19 September 2007, the US Department of Defense announced that the new GPS satellites will not be capable of implementing Selective Availability.
This means the wave of Block IIF satellites launched in 2009 (and all subsequent GPS satellites) do not support SA. As old satellites are replaced in the GPS modernization
GPS modernization
The United States' Global Positioning System , having reached Fully Operational Capability on July 17, 1995, has completed its original design goals. However, additional advances in technology and new demands on the existing system led to the effort to modernize the GPS system. Announcements from...

 program, SA will cease to exist. The modernization programme also contains standardized features that allow GPS III and Galileo systems to inter-operate, allowing a new receiver to utilise both systems to improve precision. By combining GPS and Galileo, it can create an even more precise GNSS system.

Galileo satellites

  • 30 in-orbit spacecraft (including 3 spares)
  • Orbital altitude: 23,222 km (MEO)
  • 3 orbital planes
    Orbital plane (astronomy)
    All of the planets, comets, and asteroids in the solar system are in orbit around the Sun. All of those orbits line up with each other making a semi-flat disk called the orbital plane. The orbital plane of an object orbiting another is the geometrical plane in which the orbit is embedded...

    , 56° inclination, ascending nodes separated by 120° longitude (9 operational satellites and one active spare per orbital plane)
  • Satellite lifetime: >12 years
  • Satellite mass: 675 kg
  • Satellite body dimensions: 2.7 m × 1.2 m × 1.1 m
  • Span of solar arrays: 18.7 m
  • Power of solar arrays: 1.5 kW (end of life)

Services


The Galileo system will have five main services:
Open access navigation: This will be 'free to air' and for use by the mass market; Simple timing and positioning down to 1 metre.
Commercial navigation (encrypted): High precision to the centimetre; guaranteed service for which service providers will charge fees.
Safety Of life navigation: Open service; For applications where guaranteed precision is essential; Integrity messages will warn of errors.
Public regulated navigation (encrypted): Continuous availability even in time of crisis; Government agencies will be main users.
Search and rescue: System will pick up distress beacon locations; Feasible to send feedback, confirming help is on its way.

Other secondary services will also be available.

The concept


Each satellite will have 4 atomic clocks of 2 types (2 rubidium frequency standards and 2 passive hydrogen masers); critical to any satellite-navigation system and a number of other components. These clocks will provide an accurate timing signal for a receiver to calculate the time that it takes the signal to reach the target. This information is used to calculate the position of the receiver by trilaterating
Trilateration
In geometry, trilateration is the process of determinating absolute or relative locations of points by measurement of distances, using the geometry of circles, spheres or triangles. In addition to its interest as a geometric problem, trilateration does have practical applications in surveying and...

 the difference in received signals from multiple satellites.

For more information of the concept of global satellite navigation systems, see GNSS and GNSS positioning calculation
GNSS positioning calculation
The global navigation satellite system positioning for receiver's position is derived through the calculation steps, or algorithm, given below....

.

Galileo satellite test beds: GIOVE



In 2004 the Galileo System Test Bed Version 1 (GSTB-V1) project validated the on-ground algorithms for Orbit Determination and Time Synchronisation (OD&TS). This project, led by ESA and European Satellite Navigation Industries
European Satellite Navigation Industries
European Satellite Navigation Industries, formerly called Galileo Industries until legal action prompted a name change, was a joint venture of the companies Alcatel Alenia Space and Thales , Finmeccanica , EADS Astrium and Galileo Sistemas y Servicios .The company was the primary construction...

, has provided industry with fundamental knowledge to develop the mission segment of the Galileo positioning system
Galileo positioning system
Galileo is a global navigation satellite system currently being built by the European Union and European Space Agency . The €20 billion project is named after the famous Italian astronomer Galileo Galilei...

.
  • GIOVE-A
    GIOVE
    GIOVE, or Galileo In-Orbit Validation Element, is the name for each satellite in a series being built for the European Space Agency to test technology in orbit for the Galileo positioning system.Giove is the Italian word for "Jupiter"...

     is the first GIOVE (Galileo In-Orbit Validation Element
    GIOVE
    GIOVE, or Galileo In-Orbit Validation Element, is the name for each satellite in a series being built for the European Space Agency to test technology in orbit for the Galileo positioning system.Giove is the Italian word for "Jupiter"...

    ) test satellite. It was built by Surrey Satellite Technology Ltd
    Surrey Satellite Technology Ltd
    Surrey Satellite Technology Ltd, or SSTL, is a spin-off company of the University of Surrey, now fully owned by EADS Astrium, that builds and operates small satellites. Its satellites began as amateur radio satellites known by the UoSAT name or by an OSCAR designation...

     (SSTL), and successfully launched on 28 December 2005 by the European Space Agency and the Galileo Joint. Operation of GIOVE-A ensured that Galileo meets the frequency-filing allocation and reservation requirements for the International Telecommunication Union
    International Telecommunication Union
    The International Telecommunication Union is the specialized agency of the United Nations which is responsible for information and communication technologies...

     (ITU), a process that was required to be complete by June 2006.

  • GIOVE-B
    GIOVE
    GIOVE, or Galileo In-Orbit Validation Element, is the name for each satellite in a series being built for the European Space Agency to test technology in orbit for the Galileo positioning system.Giove is the Italian word for "Jupiter"...

    , built by Astrium and Thales Alenia Space
    Thales Alenia Space
    Thales Alenia Space is an aerospace company born after the Thales Group bought the participation of Alcatel in the two joint-ventures between Alcatel and Finmeccanica, Alcatel Alenia Space and Telespazio.-History:...

    , has a more advanced payload than GIOVE-A. It was successfully launched on 27 April 2008 at 22:16 UTC (4.16 a.m. (Baikonur
    Baikonur
    Baikonur , formerly known as Leninsk, is a city in Kyzylorda Province of Kazakhstan, rented and administered by the Russian Federation. It was constructed to service the Baikonur Cosmodrome and was officially renamed Baikonur by Russian president Boris Yeltsin on December 20, 1995.The shape of the...

     time) aboard a Soyuz-FG
    Soyuz-FG
    The Soyuz-FG launch vehicle is an improved version of the Soyuz-U, from the R-7 family of rockets, designed and constructed by TsSKB-Progress in Samara...

    /Fregat
    Fregat
    Fregat is a type of rocket stage developed by NPO Lavochkin in the 1990s. Its main engine is a liquid propellant rocket that uses UDMH and N2O4 as propellants.- Specifications :...

     rocket provided by Starsem
    Starsem
    Starsem is a European-Russian company that was created in 1996 to commercialise the Soyuz launcher. Starsem is headquartered in Évry, France and has the following shareholders:* Russian Federal Space Agency...

    .


A third satellite, GIOVE-A2
GIOVE
GIOVE, or Galileo In-Orbit Validation Element, is the name for each satellite in a series being built for the European Space Agency to test technology in orbit for the Galileo positioning system.Giove is the Italian word for "Jupiter"...

, was originally planned to be built by SSTL
Surrey Satellite Technology Ltd
Surrey Satellite Technology Ltd, or SSTL, is a spin-off company of the University of Surrey, now fully owned by EADS Astrium, that builds and operates small satellites. Its satellites began as amateur radio satellites known by the UoSAT name or by an OSCAR designation...

 for launch in the second half of 2008. Construction of GIOVE-A2
GIOVE
GIOVE, or Galileo In-Orbit Validation Element, is the name for each satellite in a series being built for the European Space Agency to test technology in orbit for the Galileo positioning system.Giove is the Italian word for "Jupiter"...

 was terminated due to the successful launch and in-orbit operation of GIOVE-B
GIOVE
GIOVE, or Galileo In-Orbit Validation Element, is the name for each satellite in a series being built for the European Space Agency to test technology in orbit for the Galileo positioning system.Giove is the Italian word for "Jupiter"...

.

The GIOVE Mission
GIOVE Mission
The GIOVE Mission segment, or GIOVE-M, is the name of a project dedicated to the exploitation and experimentation of the GIOVE satellites. The GIOVE Mission is intended to ensure risk mitigation of the In Orbit Validation phase of the Galileo positioning system.-GIOVE Mission history:The GIOVE...

 segment operated by European Satellite Navigation Industries
European Satellite Navigation Industries
European Satellite Navigation Industries, formerly called Galileo Industries until legal action prompted a name change, was a joint venture of the companies Alcatel Alenia Space and Thales , Finmeccanica , EADS Astrium and Galileo Sistemas y Servicios .The company was the primary construction...

 is exploiting the GIOVE-A/B
GIOVE
GIOVE, or Galileo In-Orbit Validation Element, is the name for each satellite in a series being built for the European Space Agency to test technology in orbit for the Galileo positioning system.Giove is the Italian word for "Jupiter"...

 satellites to provide experimental results based on real data to be used for risk mitigation for the IOV satellites that will follow on from the testbeds. ESA
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...

 organised the global network of ground stations to collect the measurements of GIOVE-A/B
GIOVE
GIOVE, or Galileo In-Orbit Validation Element, is the name for each satellite in a series being built for the European Space Agency to test technology in orbit for the Galileo positioning system.Giove is the Italian word for "Jupiter"...

 with the use of the GETR receivers for further systematic study. GETR receivers are supplied 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...

 as well as the first Galileo navigation receivers to be used to test the functioning of the system at further stages of its deployment. Signal analysis of GIOVE-A/B
GIOVE
GIOVE, or Galileo In-Orbit Validation Element, is the name for each satellite in a series being built for the European Space Agency to test technology in orbit for the Galileo positioning system.Giove is the Italian word for "Jupiter"...

 data has confirmed successful operation of all the Galileo signals with the tracking performance as expected.

In-Orbit Validation (IOV) satellites


These testbed satellites will be followed by four IOV Galileo satellites that will be much closer to the final Galileo satellite design. The Search & Rescue feature is not installed. The first two satellites were launched on 21 October 2011 from Guiana Space Centre a using Soyuz launcher. Once this In-Orbit Validation (IOV) phase has been completed, the remaining satellites will be installed to reach the Full Operational Capability.
Those 4 IOV Galileo satellites were constructed by Astrium GmbH and Thales Alenia Space.

Full Operational Capability (FOC) satellites


On 7 January 2010, it was announced that the contract to build the first 14 FOC satellites was awarded to
OHB System and Surrey Satellite Technology Limited (SSTL).
Fourteen satellites will be built at a cost of 566M euros ($811M; £510M).
Arianespace
Arianespace
Arianespace SA is a French company founded in 1980 as the world's first commercial space transportation company. It undertakes the production, operation, and marketing of the Ariane 5 rocket launcher as part of the Ariane programme....

 will launch the satellites for a cost of 397M euros ($569M; £358M).
The European Commission announced also that the contract of 85 million euros for the System support covering industrial services required by ESA
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...

 for integration and validation of Galileo System was awarded to Thales Alenia Space
Thales Alenia Space
Thales Alenia Space is an aerospace company born after the Thales Group bought the participation of Alcatel in the two joint-ventures between Alcatel and Finmeccanica, Alcatel Alenia Space and Telespazio.-History:...

. Thales Alenia Space subcontract performances to Astrium GmbH
EADS Astrium
Astrium Satellites is one of the three business units of Astrium, a subsidiary of EADS. It is a European space manufacturer involved in the manufacture of spacecraft used for science, Earth observation and telecommunication, as well as the equipment and subsystems used therein and related ground...

 and security to Thales Communications
Thales Group
The Thales Group is a French electronics company delivering information systems and services for the aerospace, defense, transportation and security markets...

.

Science projects using Galileo


In July 2006, an international consortium of universities and research institutions embarked on a study of potential scientific applications of the Galileo constellation. This project, dubbed GEO6, is a 360-degree study oriented to the scientific community in its broader sense, aiming to define and implement new applications of Galileo.

Among the various GNSS users identified by the Galileo Joint Undertaking, the GEO6 project addresses the Scientific User Community (UC).

The GEO6 project aims at fostering possible novel applications within the scientific UC of GNSS signals, and particularly of Galileo.

The AGILE project is an EU-funded project devoted to the study of the technical and commercial aspects of Location-based Services (LBS)
Location-based service
A Location-Based Service is an information or entertainment service, accessible with mobile devices through the mobile network and utilizing the ability to make use of the geographical position of the mobile device....

. It includes technical analysis of the benefits brought by Galileo (and EGNOS); also studying the hybridisation of Galileo with other positioning technologies (network-based, WLAN, etc.). Within these project, some pilot prototypes were implemented and demonstrated.

On the basis of the potential number of users, potential revenues for Galileo Operating Company or Concessionaire (GOC), international relevance, and level of innovation, a set of Priority Applications (PA) will be selected by the consortium and they will be developed within the time frame of the same Project.

These applications will help to increase and optimise the use of the EGNOS services as well as the opportunities offered by the Galileo Signal Test-Bed (GSTB-V2) and the Galileo (IOV) phase.

Coins


The European Satellite Navigation project was selected as the main motif of a very high value collectors' coin: the Austrian European Satellite Navigation commemorative coin, minted on 1 March 2006. The coin has a silver ring and niobium
Niobium
Niobium or columbium , is a chemical element with the symbol Nb and atomic number 41. It's a soft, grey, ductile transition metal, which is often found in the pyrochlore mineral, the main commercial source for niobium, and columbite...

 “pill”, colour gold-brown. In the reverse, the niobium portion depicts navigation satellites orbiting the Earth. The ring shows different modes of transport (an aeroplane, a car, a container ship, a train and a lorry) for which satellite navigation was developed.

See also


  • Binary Offset Carrier modulation – the modulation family used in Galileo
  • Commercialization of space
    Commercialization of space
    Commercialization of space is the use of equipment sent into or through outer space to provide goods or services of commercial value, either by a corporation or state. Examples of the commercial use of space include satellite navigation systems, satellite television and satellite radio...

  • European Geostationary Navigation Overlay Service
    European Geostationary Navigation Overlay Service
    The European Geostationary Navigation Overlay Service is a satellite based augmentation system 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...

  • MBOC
    MBOC
    Multiplexed binary offset carrier modulation is a modulation proposed for Galileo and modernized GPS signals, which combines a sine binary offset carrier SinBOC signal with a SinBOC signal, either via weighted sum/difference or via time-multiplexing...

    - Multiplexed Binary Offset Modulation
  • Multilateration
    Multilateration
    Multilateration is a navigation technique based on the measurement of the difference in distance to two or more stations at known locations that broadcast signals at known times. Unlike measurements of absolute distance or angle, measuring the difference in distance results in an infinite number of...

     – the mathematical technique used for Galileo positioning

Further reading

  • Psiaki, M. L., “Block Acquisition of weak GPS signals in a software receiver”, Proceedings of ION GPS 2001, the 14th International Technical Meeting of the Satellite Division of the Institute of Navigation, Salt Lake City, Utah, September 11–14, 2001, pp. 2838–2850.
  • Bandemer, B., Denks, H., Hornbostel, A., Konovaltsev, A., “Performance of acquisition methods for Galileo SW receivers”, European Journal of Navigation, Vol.4, No. 3, pp 17–9, July 2006
  • Van Der Jagt, Culver W. Galileo : The Declaration of European Independence : a dissertation (2002). CALL #JZ1254 .V36 2002, Description xxv, 850 p. : ill. ; 30 cm. + 1 CD-ROM

Official websites

  • European GNSS Supervisory Authority (GSA)Europa
    Europa (web portal)
    Europa is the official web portal of the European Union . It is intended to improve the public’s interaction with EU institutions by quickly directing website visitors to the services or information they are seeking. Europa links to all EU agencies and institutions in addition to press releases...

  • Official websiteESA
    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...


Other