PARIS Europeans are hoping that the planned Galileo radio navigation system enjoys smoother sailing than its namesake.
The 3.2 billion-euro ($2.79 billion) plan to launch a rival to the U.S.-developed Global Positioning System (GPS) got final approval this past week from the European Union, despite some nagging misgivings about the cost of the biggest technology initiative in the history of the EU.
A joint project between the EU and the European Space Agency (ESA), Galileo is scheduled to begin signal transmission in 2005 and to be fully operational in 2008. It promises to offer users higher positioning accuracy and guaranteed quality-of-service levels. Europeans claim those guarantees are not available in the current GPS.
Officials in Europe called Galileo "a cornerstone of European sovereignty" and an "engine for new services" when mobile phones begin integrating navigation receivers. Many European companies have huge financial and technological stakes in the technology.
"The industry is ready to put in place an army of engineers to start the project," commented Olivier Colaitis, senior vice president of strategies at Alcatel Space (Toulouse, France) and chairman of Galileo Industries, a consortium of European aerospace companies that includes Alcatel, Alenia and Astrium. Citing the planned 2008 rollout, he added, "Time is running out. We need a hot start."
While EU transport ministers have approved 550 million euros to start up Galileo, the full ESA membership will not meet until mid-April to issue the first full-fledged call for tenders for implementing the Galileo Project. It is unclear whether U.S. companies will be permitted to participate in the project. Colaitis said that the EU has been silent on that issue to date.
Although Galileo's architecture is specified to be usable as a standalone global system, the system will be interoperable with such other global-positioning systems as GPS and Russia's GLONASS. "With Galileo, we are not reinventing the wheel; we're adding a wheel," said an ESA spokesman.
Galileo/GPS dual-mode receivers would provide the benefits of both systems, ESA claims. Those would include greater signal availability and improved performance, particularly in large cities, where high buildings can interfere with satellite signals.
"Unlike GPS, which is controlled by the U.S. military, Galileo will be run by civil authorities in Europe," the ESA spokesman said. It will "offer redundancies and the integrity required for the provision of service guarantees and support of safety-of-life applications, in addition to creating thousands of jobs in Europe."
U.S. officials had previously warned European defense ministers about the possible risk of Galileo's signals overlapping with U.S. GPS military signals. Pentagon officials said Thursday (March 28) that their first recourse would be to work with NATO to head off any compatibility problems. In a statement on the EU's decision to proceed with Galileo, the Pentagon's office of command, control, communications and intelligence said: "We expect that, due to the international and military natures of this particular issue, the GPS-Galileo discussion will proceed via NATO's communications and integration structures."
The emergence of Galileo in Europe could have implications for the U.S. electronics industry. While the United States has made GPS available without cost since 1983, Europe will charge a licensing fee to manufacturers of devices that capture Galileo's positioning signals. According to its business plan, the planned Galileo operating company would derive revenue from chip set royalties, paid by equipment providers. It also anticipates income from service providers that seek to use the encrypted signals for services beyond the basic positioning navigation and timing signals that will be offered free to all users.
The motives driving the Galileo Project are technological as well as political. Some of the key building blocks of radio navigation technologies, such as on-board atomic clocks and integrity algorithms, are "very difficult technologies" that are "not built by off-the-shelf components," said Alcatel Space's Colaitis. Acknowledging that 50 percent of the technologies needed to build Galileo have been already developed for GPS, Colaitis said, "Maybe Europe will be able to get some technologies from the United States, but there are no assurances that critical technologies can be made readily available, due to trade agreement restrictions."
Indeed, the biggest challenge for European industry in moving forward with the Galileo Project, Colaitis said, is "to translate theories into practices."
The fully deployed Galileo system will consist of 30 satellites 27 operational and three active spares positioned in three circular medium-earth-orbit planes in a 23,616-km altitude above the Earth and at an inclination of the orbital planes of 56° with reference to the equatorial plane. Galileo seeks to offer higher positioning accuracy down to just a few meters together with synchronization to within 50 nanoseconds. In contrast, GPS without using augmentation systems provides a positioning accuracy of about 10 meters and a synchronization accuracy of 500 ns, according to Alcatel Space.
While Galileo shares the same frequency band with the American GPS, it differs markedly from the U.S. system in its ability to embed "integrity" messages directly into signals for broadcast. "Galileo signals consist of two types of signals: global-positioning signals and data content," said Hans Fromm, head of Global Navigation Satellite System (GNSS) applications and user services at ESA. The latter will be used for broadcasting integrity messages in safety applications as well as for sending ancillary messages for commercial use, such as map updates or temporary map changes.
Data messages will be uplinked to Galileo satellites from the ground, stored on-board and transmitted continuously using a packet data structure that will allow urgent messages to be relayed without delay and will allow the repetition frequency of all messages to be optimized.
Meanwhile, independent global or regional integrity networks on the ground will determine the integrity of positioning information by monitoring the Galileo constellation and possibly other navigational satellite constellations. The two Galileo control centers on the ground, for example, will use the data sent from the network of Galileo sensor stations to compute the integrity information and to synchronize the time signals of all satellites and ground station clocks.
Development of such integrity computation algorithms to validate signals and update users is no mean feat, Colaitis said. "A lot of mathematical studies are required to develop an algorithm to calculate the integrity of signals. Then we need to translate that algorithm into software and applications."
This is one area of innovation that distinguishes Galileo from other navigation technologies, Fromm said. Although several new systems, including the U.S.-developed Wide Area Augmentation System (WAAS), are designed to augment GPS by adding information that heightens the accuracy of the positioning signals, such augmentation signals "are sent separately; they are not integrated in the satellite navigation signals themselves," as in Galileo, Fromm said.
Higher visibility, accuracy
Under Galileo, the broadcasting of integrity messages is handled by the medium-earth-orbit satellite constellation. That offers higher visibility and higher accuracy than are achieved by GPS augmentation systems based on one or two geostationary satellites, claimed Fromm.
Because Galileo shares a frequency band with GPS, the antennas and receiver ICs used in dual-mode, Galileo-GPS systems can be identical to those used in GPS systems today. But dual-mode receivers can't simply design in the current-generation GPS chip set, Fromm cautioned. Because Galileo is charged with providing more accurate positioning information, it is more complex and will require extra processing power, he said.
By 2008, when Galileo is predicted to be in full operation, there should be sufficient processor Mips to handle Galileo data processing in software, Fromm said.
George Leopold contributed to this story.