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Galileo (satellite navigation system)

European global navigation satellite system

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  • 8 chapters

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One of the aims of Galileo is to provide an independent high-precision positioning system so European political and military authorities do not have to rely on the United States GPS or the Russian GLONASS systems, which could be disabled or degraded by their operators at any time. The use of basic (lower-precision) Galileo services is free and open to everyone. A higher-precision service is available for free since 24 January 2023, what had previously been only available to government-authorized users. Galileo is also to provide a new global search and rescue (SAR) function as part of the MEOSAR system.

The second Galileo test satellite GIOVE-A was launched 28 December 2005, while the first satellite to be part of the operational system was launched on 21 October 2011. Galileo started offering Early Operational Capability (EOC) on 15 December 2016, providing initial services with a weak signal. In October 2018, four more Galileo satellites were brought online, increasing the number of active satellites to 18. In November 2018, the FCC approved use of Galileo in the US. As of September 2024, there are 25 launched satellites that operate in the constellation. It is expected that the next generation of satellites will begin to become operational after 2026 to replace the first generation, which can then be used for backup capabilities. Most satellites of the programme were built by OHB in Bremen, Germany, with the contribution of Surrey Satellite Technology (SSTL) in Guildford, United Kingdom.

The Galileo system has a greater horizontal accuracy than GPS in certain locations, having an accuracy of less than 1 m when using broadcast ephemeris (GPS: 3 m) and a signal-in-space ranging error (SISRE) of 1.6 cm (GPS: 2.3 cm) when using real-time corrections for satellite orbits and clocks.

History

Main objectives

In 2008, the different concepts of the three main contributors of the European Space Agency (ESA) (Germany, France and Italy) for Galileo were compared and reduced to one by a joint team of engineers from all three countries. The first stage of the Galileo programme was agreed upon officially on 26 May 2003 by the European Union and the ESA. The system is intended primarily for civilian use, unlike the more military-focused systems of the United States (GPS), Russia (GLONASS) and China (BeiDou) in that Galileo doesn't limit accuracy for non-military applications. The European system could be subject to shutdown for military purposes in extreme circumstances (such as an armed conflict). Italy and Germany led the development of the first generation of the Galileo programme, while France is playing a more prominent role in the development of the Galileo Second Generation (G2G).

Funding

The European Commission 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 included all previous years of sales. The attention that was brought to this multi-billion euro growing error in sales forecasts resulted in a general awareness in the commission and elsewhere that it was unlikely that the programme would yield the return on investment that had previously been suggested to investors and decision-makers. On 17 January 2002, a spokesman for the project stated that, as a result of US 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 completed on 26 May 2003). The starting cost for the period ending in 2005 is estimated at €1.1 billion. The required satellites (the planned number is 30) were to be launched between 2011 and 2014, with the system up and running and under civilian control from 2019. The final cost is estimated at €3 billion, including the infrastructure on Earth, constructed in 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. The base Open Service is to be available without charge to anyone with a Galileo-compatible receiver, with an encrypted higher-bandwidth improved-precision Commercial Service originally planned to be available at a cost, but in February 2018 the high accuracy service (HAS) (providing Precise Point Positioning data on the E6 frequency) was agreed to be made freely available, with the authentication service remaining commercial. By early 2011 costs for the project had run 50% over initial estimates.

Tension with the United States

Galileo is intended to be an EU civilian GNSS that allows all users access to it. Initially GPS reserved the highest quality signal for military use, and the signal available for civilian use was intentionally degraded (Selective Availability). This changed with President Bill Clinton signing a policy directive in 1996 to turn off Selective Availability. Since May 2000 the same precision signal has been provided to both civilians and the military.

Since Galileo was designed to provide the highest possible precision (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 GNSSs 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 its 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 EU official claimed that the US officials implied that they might 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 they have since reached the compromise that Galileo is to use different frequencies. This allows the blocking or jamming of either GNSS without affecting the other.

GPS and Galileo

One of the reasons given for developing Galileo as an independent system was that position information from GPS can be made significantly inaccurate by the deliberate application of universal selective availability (SA) by the US military. GPS is widely used worldwide for civilian applications; Galileo's proponents argued that civil infrastructure, including aircraft navigation and landing, should not rely solely upon a system with this vulnerability.

On 2 May 2000, the selective availability was disabled by the President of the United States, Bill Clinton; in late 2001 the entity managing the GPS confirmed that it did not intend to enable selective availability ever again. Although Selective Availability capability still exists, on 19 September 2007, the US Department of Defense announced that newer GPS satellites would not be capable of implementing Selective Availability; the wave of Block IIF satellites launched in 2009, and all subsequent GPS satellites, are stated not to support selective availability. Selective availability thus becomes moot as a practical option as old satellites are replaced in the GPS Block III programme, and eventually nonexistant. The modernisation programme also contains standardised features that allow GPS III and Galileo systems to inter-operate, allowing receivers to be developed to utilise GPS and Galileo together to create an even more accurate GNSS.

Cooperation with the United States

In June 2004, in a signed agreement with the United States, the European Union agreed to switch to a binary offset carrier modulation 1.1, or BOC(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 US national security capabilities".

First experimental satellites: GIOVE-A and GIOVE-B

The first experimental satellite, GIOVE-A, was launched in December 2005 and was followed by a second test satellite, GIOVE-B, launched in April 2008. After successful completion of the In-Orbit Validation (IOV) phase, additional satellites were launched. On 30 November 2007, the 27 EU transport ministers involved reached an agreement that Galileo should be operational by 2013, but later press releases suggest it was delayed to 2014.

Continued funding and governance issues

In mid-2006, the public–private partnership fell apart, and the European Commission decided to nationalise the Galileo programme.

In 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 a lack of additional 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 €548 million (US$755 million, £370 million) from the union's competitiveness budget for the following year and shifting some of these funds 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 €3.4 billion to be released from the EU's agriculture and administration budgets to allow the issuing of contracts to start construction of the ground station and the satellites.

In June 2009, the European Court of Auditors 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 cut the number of satellites definitively planned 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 would be available in 2013, and the CS and SOL some time later. The €3.4 billion budget for the 2006–2013 period was considered insufficient. In 2010, the think-tank Open Europe estimated the total cost of Galileo from start to 20 years after completion at €22.2 billion, borne entirely by taxpayers. Under the original estimates made in 2000, this cost would have been €7.7 billion, with €2.6 billion borne by taxpayers and the rest by private investors.

In November 2009, a ground station for Galileo was inaugurated near Kourou (French Guiana). The launch of the first four in-orbit validation (IOV) satellites was planned for the second half of 2011, and the launch of full operational capability (FOC) satellites was planned to start in late 2012.

In 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 then committed to bring the constellation above this 60% capacity. Paul Verhoef, the 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 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 completion the system will need to be subsidised 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 voted Prague, in the Czech Republic, 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 that Berry Smutny, the CEO of the German satellite company OHB-System, said that Galileo "is a stupid idea that primarily serves French interests". The BBC learned in 2011 that €500 million (£440 million) would become available to make the extra purchase, taking Galileo within a few years from 18 operational satellites to 24.

The first two Galileo In-Orbit Validation satellites were launched by Soyuz ST-B flown from Centre Spatial Guyanais on 21 October 2011, and the remaining two on 12 October 2012. As of 2017, the satellites are fully useful for precise positioning and geodesy with a limited usability in navigation.

Twenty-two further satellites with Full Operational Capability (FOC) were on order as of 1 January 2018. The first four pairs of satellites were launched on 22 August 2014, 27 March 2015, 11 September 2015 and 17 December 2015.

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