tests the first time a NASA space probe that communicates via laser with the earth. . Succeeds in transferring data, this could be the prelude to a satellite-based and thus truly spans the globe internet
If NASA probe LADEE occurs in early October in the lunar orbit, it’s astronomers all about one thing: To learn more about the extremely thin atmosphere of the moon more. Because it still holds many mysteries. LADEE should measure about how it is put together exactly how it develops and interacts with the lunar surface. For Internet companies, but especially the second project is likely to be important: The data obtained are first sent back to Earth via laser, not as before by radio. The new communication system called “Lunar Laser Communications Demonstration” offers downloads of up to 600 megabits per second. That’s six times faster than the previous data rate – and a new record in the transfer of information from space
In the LADEE mission while the system is only tested.. The main communication is the wireless technology. Nevertheless, the project of future data transmission is expected to pave the way – and give the internet cover on the earth a huge boost. The start-up Laser Light Communications in the U.S. state of Virginia is already in the starting blocks., It wants to shoot communication satellites into orbit that receive data via laser and send to
Optical data links over the airwaves, there are Although already from multiple vendors. But they work so far either in space – such as the technology of German Tesat. Or only very short distances – about between the campus or office buildings. They are found especially where barriers such as roads or water prevent the laying of fiber optic cables. The company LightPointe from San Diego about can transfer up to 2.5 gigabits per second over several hundred meters.
Thus the technology for the huge range of satellite internet, or even for those 400,000 kilometers from the moon comes into question, further developments are needed. This includes, for example, a highly sensitive detector for the photons. When it consists of LADEE mission superconducting nanowires are cooled to three Kelvin. Developed a component has the Lincoln Laboratory at the Massachusetts Institute of Technology (MIT). The detector is installed in ground-based telescopes with just one meter aperture diameter. If the telescopes increased to three meters in diameter, the system instead of the current 600 megabits could even transfer 2.5 gigabits per second, believes Don Boroson, researchers at Lincoln Lab and leader of the project. “The system demonstrated the first optical data transmission for a relatively deep space mission. When it enlarged and partly surrounded, it could potentially also extend to Mars.” As clouds block the photons are detectors in telescopes at installed three different places: in California, New Mexico and the Canary Islands. Except on the nanowire detectors is based on the lunar system, a high-speed encoding and decoding the data and further calculations and adjustments to constantly align the telescope with one another. “There’s a whole bunch of new, exciting technology is there,” said Boroson. Even more exciting for bandwidth-hungry Earthling is the prospect of a satellite-based optical network. Laser Light Communications is in the early stages of dev! elopment and hopes in four years a fleet of twelve corresponding satellite to be launched. They shall allow for continuous optical satellite-to-ground and satellite-to-satellite communications. The company plans to complete the underground fiber optic network. In the first stage, with eight satellites are scheduled download speeds of 200 gigabits per second. For comparison, the satellite company O3b has recently founded between 150 Mbps and 2 Gigabit per second via radio frequency. Other companies, such as Intelsat and Inmarsat, deliver speeds of the same order. The system of Laserlight Communications could continents with each other, bypassing bottlenecks of conventional fiber-optic network. But even more important: In case of failures – like the severed undersea cable that connects the Middle East and parts of India abklemmte 2008 – it would provide alternative line routes. The start-up plans first 48 ground stations. When clouds block the optical signal at a point can jump in this way another receiver into the breach, said Robert Brumley, CEO of parent company Pegasus Global Holding. Many more stations might contribute, because the detector units are small enough to place them on an office roof or even a truck, Brumley adds. “We are aiming for worldwide coverage.” <- AUTHOR MARKER DATA BEGIN -> ( David Talbot ) / <- RSPEAK_STOP -> ! (bsc)<- AUTHOR DATA MARKER END ->
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This text is taken from the Technology Review magazine issue 10/2013. The booklet can be ordered online here.
