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Excluding ARM, Java chip makers said they knew little or nothing about Monty before Sun presented project details at JavaOne.

CRCW12062K80FKEAHP_Datasheet PDF

Excluding ARM, Java chip makers said they knew little or nothing about Monty before Sun presented project details at JavaOne.

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.”

CRCW12062K80FKEAHP_Datasheet PDF

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.

CRCW12062K80FKEAHP_Datasheet PDF

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.”

CRCW12062K80FKEAHP_Datasheet PDF

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

This laser allows production of EUV energy that is debris-free, spectrally pure and capable of providing high-throughput lithography,” he said. We are confident that the 1500-watt laser demonstrates a practical path to cost-effective EUV lithography,” he added.

Welsh epitaxial wafer maker IQE has suffered a 27% year-on-year fall to £7.7m in Q4 sales, and says business remains tough.

IQE says the downturn in demand for optoelectronics is still hitting sales. Its production ramp-up in other areas — such as optical storage and at subsidiary IQE Silicon Compounds, which has just struck a deal to produce strained silicon wafers — has not been swift enough to offset the decline.

In a statement, IQE said: As a result, it is expected that trading in the first half of 2002 will be weaker than the second half of 2001.”

But it does expect a steady improvement” in trading through the second half.


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