Galileo positioning system
From Wikipedia, the free encyclopedia.
http://www.wikipedia.com/wiki/Galileo+positioning+system
Galileo is a planned satellite navigation system, intended as a European alternative to the US GPS. It is currently under
consideration by the European Union and the European Space Agency. The system is intended to be primarily for civil use,
unlike the US system. The US reserves the right to limit the signal strength of the GPS sytems so that non-military users can't
use it, or to shut down GPS completely, in time of conflict. The precision of the signal available to non-military users was
limited before 2000. The European system will not (in theory) be subject to shutdown for military purposes, will provide a
significant improvement to the signal available from GPS, and will be available at its full precision to all users, both civil and
military.
The European Commission had some difficulty trying to secure funding for the next stage of the Gallileo project. Its states
were wary of investing the neccessary funds at a time where budgets were threatened across Europe. Some states, such as
France, strongly supported Galileo as a means of having technological independence from the United States. Other states, such
as Germany, felt that it may be better to continue getting the service for free from the US, than paying for it themselves. The
United States, after the September 11 terrorist attacks against them, wrote to the European Union opposing the project since it
would defeat the usefulness of the US ability to shut down GPS in times of military operations. On January 17, 2002 the
spokesman for the project said that "Galileo is almost dead" as a result of this pressure.
The European Union and European Space Agency then agreed in March 2002 to fund the project, pending a review in 2003. At
a cost of €1.1 bn the required satellites will be launched between 2006 and 2008 and the system will be working, under civilian
control, from 2008.
As well as a technological achievement and practical tool, Galileo will be a political statement of EU technological
independence from the United States. In the technological independence aspect, a strong motivator is the policy of the US to
accept only US companies to deliver technology and equipment for the GPS.
External links:
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European Space Administration story
Wired story
BBC story on go-ahead for Galileo
Global Positioning System
(Redirected from GPS)
The Global Positioning System, usually called GPS, and originally named NAVSTAR, is a satellite navigation system used
for determining one's precise location almost anywhere on Earth. A GPS unit receives time signal transmissions from multiple
satellites, and calculates its position by triangulating this data. The GPS was designed by and is controlled by the United States
Department of Defense and can be used by anybody for free. The cost of maintaining the system is approximately $400 million
per year.
Technical description
The system consists of a 'constellation' of 24 satellites in 6 orbital planes. The GPS satellites were manufactured by Rockwell;
the first was launched in 1978 and the final (24th) satellite was launched in 1994. Each satellite circles the Earth twice every
day at an altitude of 20,200 kilometers. The satellites carry atomic clocks and constantly broadcast the precise time according
to their own clock, along with administrative information, including the orbital elements of their own motion, as determined by
a set of ground-based observatories.
The receiver does not need a precise clock, but it needs to have a clock with good short-term stability and contact to four
satellites in order to unambiguously compute its own latitude, longitude, elevation and the precise time. The receiver starts
with an approximate time and computes the distances to the four satellites based on a comparison of their broadcast time
signals to the receiver's time. Furthermore, the receiver can calculate the precise locations of the four satellites from the
broadcast information stream. The receiver should then be located at the intersection of four spheres, each with a radius equal
to the time delay between the satellite and the receiver multiplied by the speed of the radio signals. In general, the 4 spheres
will not intersect however, because the initial local time was only approximate. The receiver then applies an offset to the local
time, until the computed four spheres intersect. That intersection point gives the precise location of the receiver, and the offset
gives the precise time. If elevation information is not required, only three satellites need to be contacted.
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In order to allow a precise determination of the time delay between satellite and receiver, the satellite sends a repeating 1023
bit long pseudo random sequence?; the receiver knows the seed of the sequence, constructs an identical sequence and shifts it
until the two sequences match. Different satellites use different sequences, which allows them all to broadcast on the same
frequency, 1,575.42 MHz.
The calculations are complicated by the fact that the speed of radio waves is not constant in the atmosphere and is affected by
atmospheric conditions and angle of entry, among other factors. The receiver contains a mathematical model to account for
these influences, and the satellites also broadcast some related information which helps the receiver in estimating the correct
speed of propagation.
A minor detail: the atomic clocks on the satellites are set to "GPS time", which is the number of seconds since 24:00:00,
January 5, 1980. It is ahead of UTC because it doesn't follow leap seconds. Receivers thus apply a clock correction factor
(which is periodically transmitted along with the other data) and optionally adjust for a local time zone in order to display the
correct time.
The accuracy of GPS can be improved in a number of ways:

Using a network of fixed ground based reference stations. These stations broadcast the difference between the
location given by GPS and their real location, and clients can then correct their position by the same amount. This
method is called Differential GPS or DGPS. The accuracy of DGPS without degradation of GPS is less than a meter.
DGPS was especially useful when GPS was still degraded (via the "Selective Availability" described above), since
DGPS could nevertheless provide 5-10 meter accuracy. The DGPS network has been mainly developed by the Finnish
and Swedish maritime administrations in order to improve safety in the archipelago between the two countries.

The Wide-Area Augmentation System (WAAS). This uses a number of additional satellites to transmit correction
data, including information on ionospheric delays, individual satellite clock drift, and suchlike. Although only a few
WAAS satellites are currently available (in 2002), it is hoped that eventually WAAS will provide sufficient reliability
and accuracy that it can be used for critical applications such as GPS-based instrument approaches in aviation
(landing an airplane in conditions of little or no visibility).

A Local-Area Augmentation System (LAAS). This is similar to WAAS, in that similar correction data is used. But in
this case, the correction data is transmitted from a local source, typically at an airport or another location where
accurate positioning is needed. This correction data is typically useful for only about a thirty to fifty kilometer radius
around the transmitter.
Applications
The primary military purpose is to allow improved command and control of forces through an enhanced ability to accurately
specify target locations for cruise missiles or troops. The satellites also carry nuclear detonation detectors.
The systems is used by countless civilians as well, who can use the GPS's Standard Positioning Service worldwide free of
charge. Low cost GPS receivers (price $100 to $200) are widely available. In the past, the civilian signal was degraded, and a
more accurate Precise Positioning Service was available only to the United States military and other, mostly government users.
However, on May 2, 2000, Bill Clinton announced that this "Selective Availability" would be turned off, and so now all users
enjoy nearly the same level of access, allowing a precision of position determination of less than 20 meters. For military
purposes, "Selective Deniability" may still be used to, in effect, jam civilian GPS units in a war zone while still allowing
military units to have full functionality. Military (and selected civilian) users still enjoy some technical advantages which can
give quicker satellite lock? and increased accuracy.
Other systems
For a list of other systems, see satellite navigation system.
External links:
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Peter H. Dana: Global Positioning System Overview, http://www.colorado.edu/geography/gcraft/notes/gps/gps_f.html
The FAA has more information on GPS, WAAS, LAAS, and DGPS at http://gps.faa.gov/FAQ/index.htm
U.S. Army Corps of Engineers manual: NAVSTAR HTML and PDF (328 pages)
Greg Goebel: "Navigation Satellites and GPS", http://vectorsite.net/ttgps.html
See also:
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
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Allan variance
Geocaching
Degree Confluence Project
Satellite navigation system
From Wikipedia, the free encyclopedia.
Satellite navigation systems use radio time signals transmitted by satellites to enable mobile receivers on the ground to
determine their exact location.
An early predecessor was the ground based Loran system, which didn't use satellites. The first satellite navigation system was
Transit, a system deployed by the US military in the 1960's. Transit's operation was based on the Doppler effect: the satellite
travels on a well-known path and broadcasts on a well known frequency. The received frequency will differ slightly because of
the movement of the satellite with respect to the receiver. By monitoring this frequency shift over a short time interval, the
receiver can determine its location.
Modern satellite navigation systems requires the reception of signal from several satellites, all of which broadcast the satellite's
location, and precise time signals. The satellites carry atomic clocks. The receiver characterizes the time-of-flight of the signals
from several satlites and computes its location. It can also compute the precise time.
The best known satellite navigation system is the United States' Global Positioning System (GPS). As of 2002 the GPS is the
only fully functional satellite navigation system.
The Russian counterpart to GPS is called GLONASS and was used as a backup by some commercial GPS receivers. However
the GLONASS constellation is currently (as of 2001) in very poor repair, rendering it almost useless as a navigation aid.
The European Union and European Space Agency have agreed (March 2002) to introduce their own alternative to GPS, called
Galileo, pending a review in 2003. At a cost of about $ 2.5 billion (2.5 · 10 9 dollars) the required satellites will be launched
between 2006 and 2008 and the system will be working, under civilian control, from 2008.
http://www.esa.int/export/esaSA/GGGMN850NDC_navigation_0.html
What is Galileo?
Galileo
Galileo will be Europe’s own global navigation satellite system, providing a highly accurate, guaranteed global
positioning service under civilian control. It will be inter-operable with GPS and GLONASS, the two other global
satellite navigation systems. 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, however, Galileo will deliver real-time positioning
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accuracy down to the metre range, which is unprecedented for a publicly available system. 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.
The first experimental satellite, part of the so-called Galileo System Test Bed (GSTB) will be launched in late 2004.
The objective of this experimental satellite is to characterize the critical technologies, which are already under
development under ESA contracts. Thereafter up to four operational satellites will be launched in the timeframe
2005-2006 to validate the basic Galileo space and related ground segment. Once this In-Orbit Validation (IOV)
phase has been completed, the remaining satellites will be installed to reach the Full Operational Capability (FOC)
in 2008.
The fully deployed Galileo system consists of 30 satellites (27 operational + 3 active spares), positioned in three
circular Medium Earth Orbit (MEO) planes in 23616 km altitude above the Earth, and at an inclination of the orbital
planes of 56 degrees with reference to the equatorial plane. Once this is achieved, the Galileo navigation signals
will provide a good coverage even at latitudes up to 75 degrees north, which corresponds to the North Cape, and
beyond. The large number of satellites together with the optimisation of the constellation, and the availability of the
three active spare satellites, will ensure that the loss of one satellite has no discernible effect on the user.
Two Galileo Control Centres (GCC) will be implemented on European ground to provide for the control of the
satellites and to perform the navigation mission management. The data provided by a global network of twenty
Galileo Sensor Stations (GSS) will be sent to the Galileo Control Centres through a redundant communications
network. The GCC’s will use the data of the Sensor Stations to compute the integrity information and to
synchronize the time signal of all satellites and of the ground station clocks. The exchange of the data between the
Control Centres and the satellites will be performed through so-called up-link stations. Five S-band up-link stations
and 10 C-band up-link stations will be installed around the globe for this purpose. As a further feature, Galileo will
provide a global Search and Rescue (SAR) function, based on the operational Cospas-Sarsat system. To do so,
each satellite will be equipped with a transponder, which is able to transfer the distress signals from the user
transmitters 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 him that his situation has been detected and that help is under
way. This latter feature is new and is considered a major upgrade compared to the existing system, which does not
provide a feedback to the user.
Last update: 5 April 2002
Why Europe needs Galileo
Galileo
Satellite navigation users in Europe today have no alternative other than to take their positions from US GPS or
Russian GLONASS satellites. Yet the military operators of both systems give no guarantee to maintain an
uninterrupted service. Satellite positioning has already become the standard way of navigating on the high seas: in
the near future, its use will spread to land and air. If the signals were switched off tomorrow, many ships’ crews
would be hard pressed to revert to traditional navigation methods using almanacs and sextants. In a few years'
time, when the use of satellite positioning has spread, the implications of a signal failure will be even greater,
jeopardising not only the efficient running of transport systems, but also human safety.
As far back as the early 1990s, the European Union saw the need for Europe to have its own global satellite
navigation system. 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 Ariane launcher and the Airbus. The European Commission
and European Space Agency joined forces to build Galileo, an independent system under civilian control which will
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be guaranteed to operate at all times, bar the direst emergency. Galileo is now at the point of moving from
definition to full-scale development.
European independence is the chief reason for taking this major step. However, other subsidiary reasons include:

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By being inter-operable with GPS and GLONASS, Galileo will be a cornerstone of the Global Navigation
Satellite System (GNSS). This system will be under civilian control and will allow positions to be
determined accurately for most places on Earth, even in high rise cities where buildings obscure signals
from satellites low on the horizon. This is because the number of satellites available from which to take a
position more than double.
By placing satellites in orbits at a greater inclination to the equatorial plane than GPS, Galileo will achieve
better coverage at high latitudes. This will make it particularly suitable for operation over northern Europe,
an area not well covered by GPS.
With Galileo, Europe will be able to exploit the opportunities provided by satellite navigation to the full
extent. GNSS receiver and equipment manufacturers, application providers and service operators will
benefit from novel business opportunities. Under request from the European Commission,
PricewaterhouseCoopers (PwC) prepared a study on the business plan for the Galileo programme.
Last update: 11 March 2002
Who's involved in Galileo?
Galileo satellite
Galileo is a joint initiative of the European Commission (EC) and the European Space Agency (ESA).
The EC is responsible for the political dimension and the high-level mission requirements. The EC initiated in
particular studies on the overall architecture, the economic benefits and the user needs. These include the GALILEI
studies that address the local architectures, interoperability and signals and frequencies. Moreover, they provide a
market observatory and cater for investigations into legal, institutional, standardisation, certification and regulatory
issues.
ESA’s responsibility covers the definition, development, and in-orbit validation of the space segment and related
ground element. Work on new technologies needed for the constellation and the ground segment has been
continuing at ESA's technical centre, ESTEC in the Netherlands since a number of years already. These critical
technologies include the development of high precision clocks to be installed on-board the satellites (applying
rubidium and passive hydrogen maser frequency standards), on-board timing units for steering the individual clocks
to a common Galileo System Time, signal generators to produce the positioning signals that the Galileo spacecraft
will broadcast; power amplifiers, radio-frequency multiplexers and antennas and telecommand & telemetry
transponders. In parallel, work is progressing on the Galileo System Simulation Facility (GSSF) to test strategies
for coping with contingencies when the full system is up and running and on the Galileo Signal Simulation Facility
which supports of the fine-tuning of the Galileo signal design. In addition, ESA has started working on technologies
needed for Galileo receivers. Good progress has also been made with the first version of the Galileo System Test
Bed (GSTB V1) which will allow engineers to validate Galileo-specific control algorithms, such as clock
adjustments, and procedures for predicting individual satellite orbits, before the full system goes into operation. The
second phase of the GSTB will comprise a test satellite and will allow critical technologies to be tested in medium
Earth orbit.
Last update: 11 March 2002
Market prospects and business opportunities
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Galileo constellation
Galileo is facing a market with huge opportunities for growth in the next few years.
The Global Navigation Satellite Services (GNSS) market will be derived from the value-added services and
products provided by satellite radio navigation for transport by road, rail, air and sea, fisheries and agriculture, oil
prospecting, civil protection activities, building and public works. The telecommunications sector will be
revolutionised with the introduction of Galileo allied with GSM or UTMS and will provide the market with combined
communication and position determination services of a very-high level.
According to a recent study, this window of opportunity gives Galileo an estimated worldwide GNSS market size of
1.800 million users in 2010 and 3.600 users in 2020.
Galileo will allow European industry to directly benefit from the evolution of the GNSS market, which will definitely
become an asset for the European economy.
The existence of Galileo will provide considerable amount economic and social benefits to the world in general, and
to Europe in particular. These benefits are also generated due to the introduction of complementary capabilities in
the GNSS by Galileo.
A recent analysis indicates a cost/benefit ratio of 4.6, which is higher than any other infrastructure project in Europe
and does only take into account benefits from the air and sea transport sectors.
Nevertheless, other studies support the case that further benefits will arise from route guidance, improved personal
emergency, management of taxis and ambulances, less pollution by reduction of travel times and creation of 140
000 jobs. An estimate of all benefits for the period 2000 and 2020 is illustrated below. Economic benefits 62.000
million Euros Social benefits 12.000 million Euros Total benefits 74.000 million Euros The total investment cost for
the Galileo operable system is some 3,2 billion Euros. From 2008 onwards the annual cost will be around 220
million Euros including operations, maintenance and replenishment.
These values assume a constellation 30 Medium Earth Orbit Satellites and global, regional, and local distribution.
Galileo involves three phases as follows:



Development and validation phase (2001-2005)
1. Consolidation of Mission Requirements;
2. Development of satellites and ground-based components;
3. Validation of the system “in orbit”.
Deployment phase (2006-2007)
1. Construction and launch of satellites;
2. Installation of the complete ground segment.
Commercial operation phase (from 2008)
The Design, development and In-Orbit Validation Phase is to be co-funded by the European Space Agency and by
the European Commission.
While funded by public resources, Galileo remains open to partners originating from the private sector particularly
for the operational phase.
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The complexity of the programme and in particular the interactions between the various technical and
programmatic aspects require clear understandings on the responsibilities of the parties involved. The rules to be
applied for the deployment and operations phase will be dependent on a number of factors, some of them not
being fully known yet. They will be defined in parallel with the preparation of the public private partnership.
During the interim period the European Commission will continue overseeing the programme in all programmatic
and political aspects and the European Space Agency will assume responsibility for the development of the Galileo
infrastructure.
Last update: 11 March 2002
Europe GPS Plan Shelved
By Steve Kettmann
http://www.wired.com/news/politics/0,1283,49778,00.html
2:00 a.m. Jan. 17, 2002 PDT
BERLIN -- Exasperated European officials say U.S. pressure appears to have torpedoed a $3 billion project to build
a European version of the U.S. global positioning system, which uses signals from orbiting satellites to track
geographical position within 36 meters.
The proposed system, dubbed Galileo, was intended to give Europeans more autonomy, both industrially and
militarily. That's no small concern, since the United States can selectively block access to GPS, as it has during the
military campaign in Afghanistan.
Also, European plans to develop a rapid-reaction military force will become much more credible with their own GPS
in military operations.
But U.S. Deputy Secretary of Defense Paul Wolfowitz sent a letter to all 15 European Union defense ministers last
month, urging them to influence their governments not to proceed with Galileo. That deferred any decision on the
project, and now looks to have brought its momentum to a halt.
"Galileo is almost dead," Gilles Gantelet, spokesman for Loyola de Palacio, the European commissioner in charge
of the project, said.
"We expect that we could have the decision by March at the latest. If there is no decision in March, then we could
consider Galileo ... dead."
Wolfowitz's rationale, according to Gantelet and published reports, was that the United States Defense
Department, which funds and operates GPS, plans to upgrade the system's capabilities and use more frequencies
for signals. The European system, Wolfowitz reportedly cautioned, could interfere with that.
But Gantelet questions that claim. He said the Europeans have communicated to the U.S. government plans to
avoid any technical problems with operating two systems.
"We consider all the technical aspects to have already been dealt with or easy to overcome," he said. "We think it's
mainly now a political decision."
But it's also possible that U.S. pressure helps give European governments cover so they can shy away from such
an expensive project. That was the view Turkey's ambassador to NATO expressed on Monday.
"I know there are some problems with (Galileo)," said Onur íymen, whose country is a member of NATO, but not
the EU. "We can perhaps not expect to have everything at once."
"The important thing is to have an awareness that if the European Union wants to have its contributions to
European defense, they have to spend money for that. I can't say that the Europeans are reluctant in improving
their militaries, but whether their budgets are enough for that, it's an open question."
The politics of the project -- and the bitterness likely to be generated by its demise -- are not without their sense of
drama.
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President Jacques Chirac of France was quoted in the International Herald Tribune as saying that if Europe did not
pursue Galileo and other space projects, the failure "would lead inevitably to a vassal status, first scientific and
technical and then industrial and economic."
Timing is a major issue for Galileo. The Europeans believe the project can earn significantly more than it will cost,
but only if Galileo moves forward in the near term. They say it must be up and running by 2008 to turn a profit.
"One advantage of Galileo is that it will be better than the current GPS system, and it will arrive on the market
before the new generation of American system," said Gantelet. "But if the delay is too long, there will be no interest
from consumers in using it."
Most frustrating for the Europeans is that, in essence, the Americans don't trust them with so powerful a tool. The
Europeans argue that it makes sense for the Western community to have more than one system, just in case.
"It's important for Europe to develop its system, and important for all the Western countries to develop another
system that is not a competitor to GPS, but could be alongside it," said Gantelet. "With tough times that are
starting, you don't know that there will be no terrorist attacks against the GPS. It's more reliable to have two
systems."
That argument has not, so far, swayed the thinking at the Pentagon.
Have a comment on this article? Send it.
Printing? Use this version.
E-mail this to a friend.
See also:
Military Wary of Map's Release
New Weapons for a New War
Row, Row, Row Your GPS Boat
Everybody's got issues in Politics
Related Wired Links:
Military Wary of Map's Release Dec. 12, 2001
Row, Row, Row Your GPS Boat Nov. 17, 2001
Quest for Future-Car Standards Nov. 9, 2001
Solar System on a Floppy Nov. 7, 2001
Where's E911? Nowhere to Be Found Oct. 18, 2001
New Weapons for a New War Oct. 9, 2001
Tuesday, 26 March, 2002, 15:58 GMT
Green light for Galileo project
http://news.bbc.co.uk/1/hi/sci/tech/1893022.stm
The money for Galileo is released in stages
Europe is to press ahead with plans to build a network of navigational satellites.
The Galileo system will send precise data to drivers, sailors, mobile phone and computer users, allowing them to
find their exact locations on the surface of the planet. European Transport ministers gave the green light to the
project at a meeting in Brussels.
Galileo will be a rival to the existing Global Positioning System (GPS) run by the United States - although the EU
says the two networks will be compatible.
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Galileo will cost 1.1 billion euros (Ł0.7bn) of EU money to move from the design phase into space. The investment
will allow researchers to test technology in orbit before the entire network of 30 satellites is deployed.
The final roll-out of Galileo will require substantial further funds.
Security issues
EU Transport Commissioner Loyola de Palacio told a news conference on Tuesday: "We now have a 'yes' for
Galileo which signifies Europe's wish to be present in the international scene in the areas of research, technology
and industrial development."
She was speaking after EU transport ministers signed off 450 million euros ($396 million) Why have Galileo?
of funding.
Expected to be more
This will pay for the next phase of the development programme. The money comes on
than 400 million sattop of the 100 million euros already authorised and 550 million euros committed to the
nav users by 2015
project by the European Space Agency (Esa).
European aerospace
Galileo will lead Europe into conflict with the US, which has security concerns about the
and electronics firms
building of a navigational network to rival its own system.
say it will create more
GPS, like the Russian Glonass system, is a military-run network and can be downgraded
than 100,000 jobs
or taken offline if an enemy attempts to use the data to launch guided missiles, for
Rescue services will
example.
be able to pinpoint a
By contrast, Galileo will be a civilian-run operation that will be guaranteed in all but the
driver's exact location
direst circumstances so services that are safety-critical - landing planes, for example if they are involved in
can rely on the data.
an accident
"Only the realisation of this civil system will allow the beginning of the development of the
Will allow someone to
use of satellite navigation in conditions which are suitable for Europeans," French
find their way in an
Transport Minister Jean-Claude Gayssot said in a statement.
unfamiliar city using
"It will allow the European Union to liberate itself from dependence on the American GPS
their mobile phone
system," he added.
Future horizons
Ministers also agreed on the structure of a new management company to oversee Galileo's development.
EU governments want to see private enterprise involved in the project but exactly how this should be co-ordinated
has yet to be decided.
Private firms will not be allowed to join the Galileo management board at least until after it has finished putting
projects out to tender.
Galileo should be fully operational in 2007. Some critics have questioned the need for another satellite navigation
network when GPS seems to serve most users' needs perfectly well.
But proponents argue that navigational services will become increasingly lucrative in the coming years, especially
with the emergence of new mobile phone and pocket computer applications.
Also, because Galileo will be inter-operable with GPS and Glonass, satellite navigation services should become
more accurate and reliable in those areas that have been poorly served so far - and this includes some areas of
Northern Europe.
In addition, many see a political need to be independent of the US on major projects. It was just this kind of thinking
that led to the Ariane space rocket programme and the Airbus consortium of European plane manufacturers.
What is Galileo?
Europe's own global satellite navigation system
Will work alongside US GPS and Russian Glonass systems
Promises real-time positioning accuracy down to one metre
Guaranteed under all but most extreme circumstances
Suitable for safety-critical systems - can run trains, guide cars and land planes
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Quo Vadis Galileo?
http://www.galileosworld.com/galileosworld/article/articleDetail.jsp?id=30908
GNSS 2002 Keynote Address
July 1, 2002
By: Vidal Ashkenazi
At long last, it happened! As they say in French, “Mieux vaut tard que jamais” or, in English, “Better late than never!”. On 26
March 2002, the Council of EU Transport Ministers agreed to launch the Development Phase of the Galileo Project, and
requested the European Commission to set up the Joint Undertaking without delay, in cooperation with the European Space
Agency. Coming after a great deal of hesitation and procrastination over a period of nearly 15 months, the added qualification
of “without delay” was remarkable, even by the normal standards of politicians. Needless to say, the decision followed the
corresponding unanimous conclusion of the heads of EU governments (the EU Council) which met in Barcelona two weeks
earlier.
The Transport Ministers also re-affirmed that Galileo is a civilian programme under civil control, and released the €450 million
earmarked for financing the Development Phase, together with a similar amount allocated by the European Space Agency
(ESA), which took a positive decision on Galileo last year. The Transport Council expects the European Commission to inform
the Council on the ‘tendering procedure’, which will be put in place by the Joint Undertaking (JU), which incidentally may
also include in its composition large private companies subscribing €5 million or more. This will happen by the end of 2003,
when the Transport Council will decide on the release of Community funds for the final Deployment and Operation phases of
the project, to guarantee the continued sound financial management of the Galileo Programme. The Transport Council also
made a key technical demand. It specifically stated that it expects Galileo to be ‘inter-operable’ with the existing satellite
navigation systems, and particularly with the current GPS and its potential successor system(s). This should be achieved
through an EU–US agreement to be negotiated as soon as possible. Finally, it instructed the Joint Undertaking, in collaboration
with all interested parties, to prepare a proposal for the optimal integration of EGNOS into the Galileo programme.
Let me dwell on the issue of “interoperability with GPS”. Over the last couple of months, I had the rare privilege of briefings
over the apparent gulf separating the European and American perceptions of Galileo. Like all discussions between two good
friends, two close colleagues or a co-habiting couple, who hold apparently diametrically opposed views on a certain issue, this
occasionally degenerated from passionate argument to breaking of contact, and even name (and adjective) calling. At the end
of February this year, I was invited by the US Interagency GPS Executive Board (IGEB) to talk about a topic of my choice in
Washington DC. I chose a harmless and non-controversial topic, entitled “Galileo: Friend or Foe?”. To my amazement, this
was accepted. Subsequently, when I was informed that the audience would consist of 30 to 40 people representing US
government departments, such as the Department of Commerce, the Department of Transportation, the Department of Industry,
the Department of Defense, the State Department and the CIA, I panicked and tried to give it up. I was reassured that all would
be well, and that there was not the remotest chance of having to extend my visit to Guantanamo Bay in Cuba. I relented and
accepted the invitation.
To prepare myself for this presentation, I read all the available material on the Trans-Atlantic Galileo controversy, and I also
received a high level briefing on these issues from the Commission. It soon became clear to me that the single most
controversial issue was the US point of view that some aspects of Galileo, most notably the proposed “Public Regulated
Service” (PRS) presented a serious security risk in times of crisis. In total contrast, the European perception was that “security
was not the main issue, but rather the US desire to protect its economic and commercial interests”. Surely, this is a very wide
gap between the two points of view across the Pond (the Atlantic Ocean), almost as wide as the argument about the “half-full
versus the half-empty bottle of wine”.
In my presentation, I concentrated on the substantial contribution Galileo would make and the clear advantages a dual-satellitenavigation-system would bring, compared to the present GPS only system. A fully interoperable GPS-Galileo configuration
would provide much higher positioning accuracies, a significant increase in system integrity, for safety critical applications,
and an alternative operational system in case of critical failure of the single satellite navigation system. I illustrated this last
point, not only by quoting from the John Volpe Centre Report on the “Vulnerability of Transportation Infrastructure Relying
on GPS”, but also by listing a series of publicly acknowledged instances of faulty GPS navigation message data, numerous
scheduled and unscheduled GPS outages, as well as analogies to some public failures of so-called totally safe systems, such as
the computer system of the London Stock Exchange, which failed so spectacularly one bright day in April 2001 and caused
havoc in the financial world.
In the discussion period, which followed my presentation, I was very surprised to notice that most of the all-American
audience seemed to agree with me that Galileo would be a good thing for GPS. In one intervention, a US industrialist pointed
out that he could not understand the argument that Galileo would harm the US economic and commercial interests. He
suggested that, just as the best dual GPS-Glonass receivers were built in the US, so would the best GPS-Galileo receivers. He
may or may not be right with this prediction, but he seemed to welcome the challenge. This presentation in the US Department
of Commerce, and the subsequent discussion, was an eye-opener for me. It was obvious that Galileo was seen as a welcome
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addition to satellite navigation, provided that it will be interoperable with GPS, especially considering that all these benefits
would be derived without any contribution to costs from the long suffering US taxpayer. That can’t be bad.
I was also asked several questions from the floor about the proposed financing of Galileo, which I did my best to answer.
Unfortunately, although I prepared myself well, I did not feel very comfortable on this issue, even though my company NSL
was part of the consortium led by PricewaterhouseCoopers, which carried out a study on the economic viability of Galileo. The
Consortium produced a report in November last year, which was entitled “Inception Study to Support the Development of
Business Plan for the Galileo Programme”. This was a thick report, with a 17-page Executive Summary which I read a couple
of times (the Summary, not the Report). It contained all the usual terms you would expect to find in similar reports by
management and financial consultants, which are retained by government, business organisations and even by universities
these days.
Public-Private-Partnership, projected revenue streams, cost benefit ratios, concession company models, the lot. I said I did not
feel comfortable with these issues, firstly, because I am not a financial expert, and also because, frankly, I think that
considering what is at stake, all this pales into insignificance. I understand that the projected cost of Galileo of €3.6 billion is
the price of 150 km of semi-urban motorway, or just one track of the main tunnel for the proposed high-speed rail link between
Lyon and Torino.
As someone said before, could you possibly visualise a similar debate taking place in Washington DC, in the early 1970’s,
when the US was considering the deployment of GPS? Had a cost benefit analysis been carried out then, I am sure GPS would
have never seen the light of day. After all, it was just designed for military navigation, with modest accuracy and hardly any
integrity requirements. Technically, the system was to provide the user with continuous positioning and time, by using a
modulation of pseudoranges. Differential GPS, carrier phase GPS, augmented GPS, safety critical integrity, etc,… were not
even mentioned, simply because they did not exist. The system was planned to become a so-called force-enhancer, capable of
adding to the combat effectiveness of the US forces, and those of its NATO allies. Who could then predict the emergence of
literally hundreds of civilian applications in geodesy, geophysics, oceanography, surveying and mapping, timing, meteorology,
civil engineering, offshore exploration, fleet management, agriculture and fisheries, space and leisure? Luckily there was no
cost benefit analysis, and GPS went ahead. Incidentally, while we are on the subject of management and financial consultants,
I could not miss this opportunity, now that I am in Copenhagen, of asking my Danish friends if Arthur Andersen, who founded
that famous company, is related to your wonderful storyteller Hans Christian Andersen, or is it just a coincidence?
Let us now try and look into the short and medium term future. As we heard, according to the timetable for the Galileo
programme the Development and Validation Phase, which has just begun, will last until about 2005, when the first Galileo
satellites are ready for launch. This will be followed by the Deployment Phase in 2006–2007, and finally the Commercial
Operation Phase, which is due to begin in 2008. The Joint Undertaking, which is tasked to manage the programme, will
initially have representatives only from the European Community (the Commission) and the European Space Agency. Later
on, representation may be broadened to include other organisations, such as the European Investment Bank and private
companies willing to pay a membership fee. The assumption here is that these companies will clearly see an opportunity for
themselves in the emerging Galileo project, and will be willing to invest in its development, in the hope of future profits. I
think the only companies that will clearly benefit from the Development and Deployment phases of Galileo will be those
specialising in putting together satellite systems, ie companies building the required space and ground infrastructure for the
system, and those involved in launching the satellites into orbit. I cannot see how these specialist companies can convince their
shareholders that, once Galileo is up and running, they will immediately start collecting large revenues. Of course, this is
theoretically possible, if such companies change their mainstream business model, from building space and ground systems, to
operating a service-oriented concession or to developing new revenue producing applications. However, if you study the
history of GPS over the last 30 years, you will realise that this is highly unlikely. GPS was designed, built, serviced and
upgraded by a succession of well known US specialist space companies, which were awarded government contracts in
competitive tenders. Throughout this process, the system was managed by the Department of Defense, later joined by the
Department of Transportation, representing civil interest in the utility.
In the early days, civilian use of GPS was restricted to the downgraded SPS (Standard Positioning System), which offered
users a free navigation tool, with a positioning accuracy of 30 to 50 metres. It did not take long before human ingenuity
interfered, and the Differential GPS (DGPS) technique was developed, leading to relative positioning accuracies of 1 to 2
metres. However, the real breakthrough came in the early 1980’s, when two radio astronomers from MIT, Shapiro and
Counselman, proposed using the carrier frequency phase rather than the pseudorange modulation, for GPS measurements, just
as they did in Very Long Baseline Interferometery (VLBI), with signals from extra-gallactic radio sources (or as someone said,
“God’s own GPS”). This was the beginning of centimetric (or even millimetric) GPS. Hundreds of civilian applications
followed in science, engineering, commerce and industry. The rest is history. This is important, because history usually repeats
itself. What I am referring to now are the young inventive researchers and scientists, who will emulate Shapiro and
Counselman, or Javad Ashjaee (who fell upon the first ‘roving’ carrier phase receiver without realising it, when he used to
work as a young engineer at Trimble) or Benjamin Remondi (who first proposed an ingenious way of solving the ‘integer
ambiguity’ problem). These original and inventive solutions did not come about by decree or design, nor were they proposed
by a committee after a long debate. Surely, the naming of the European satellite navigation system as Galileo, must carry a
certain intellectual responsibility. Hopefully, over the next few years, there will be several new and original ideas which will
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do to Galileo and to the dual satellite navigation system what carrier phase did for GPS. Equally, one would hope that new
concepts will be developed, which will make the current concepts of ‘local and wide area augmentations’ and ‘integrity
techniques’ seem outdated.
Finally, the real challenge will be when the current concept of satellite navigation, based on heavy GPS-like MEO (Middle
Earth Orbit) satellites, first proposed in the early 1970’s, will give way to other solutions, involving the much cheaper mini
(<1000 kg), micro (<100 kg), or even nano (<10 kg) satellites, in LEO (Low Earth Orbit), IGSO (Inclined Geo-Synchronous
Orbit) or other configurations. Is this going to upset the Galileo Programme, now that all has been decided? I can assure the
European Commission and the European Space agency that this is unlikely to happen this year, next year, or even before 2008,
when Galileo will become operational. Of course, one has to be very careful when expressing contrary opinions, especially
when these border on heresy. You will recall that, as an Astronomer, Galileo Galilei was an ardent believer in Copernican
theories, and had a marked tendency to use all his astronomical discoveries as evidence of Copernicanism, and he did so with
great verbal and mathematical skill. The Copernican theory suggested that everything goes around the Sun which, as we all
know, is contradictory to the Scriptures which profess a Geo-Centric Universe. Inevitably this attracted the attention of the
Inquisition, which was rampant at the time, and in 1616 Galileo was summoned to Rome, under suspicion of heresy, and
condemned to house arrest for life, at his Villa Arcetri near Florence. He was also forbidden to publish. By the standards of the
time, he got off rather lightly. We don’t want that, and Brussels is not Florence.
So when is the next novel satellite navigation system going to happen? 2015? 2020? Well, scientific prediction is a risky
business, and I shall conclude this presentation with a few examples of famous predictions by some equally famous men, two
Europeans and two Americans.
“Heavier than air flying machines are impossible.”
- Lord Kelvin, President of the Royal Society (1895)
“Aeroplanes are interesting toys, but of no military value.”
- Maréchal Ferdinand Foch, Professor of Strategy at the Ecole Supérieure de Guerre (1908)
“There is no likelihood that man can ever tap the power of the atom.”
- Robert Millikan, Nobel Prize winning physicist (1923)
“While theoretically and technically television may be feasible, commercially and financially I consider it an impossibility.”
- Lee de Forest, Inventor of the vacuum tube (1926)
Ladies and Gentlemen, I hope our predictions on the future of Galileo and satellite navigation will be a little more accurate.
Thank you.
__________________
Professor Vidal Ashkenazi is Chief Executive of Nottingham Scientific Limited (NSL). He has the degrees of Dr of Philosophy
and Dr of Science from the University of Oxford. He is a Fellow of the Royal Academy of Engineering, and has acted as a
Consultant to a large number of government and commercial organisations.
Professor Vidal Ashkenazi CEO, Nottingham Scientific Ltd University Park, Nottingham NG7 2RD United Kingdom
vidal.ashkenazi@nottingham.ac.uk
Further links at:
http://www.cpgps.org/links/Links.html
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