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An Impressive Demo — Oerlikon Space Laser Communication First
When large quantities of data need to be transmitted rapidly back and forth between satellites, a team from Oerlikon Space had demo’d the feasibility of a laser link with an effective distance of 1.5 million kilometers—for the first time, ever. Links such as this will be able to transmit data across huge distances through the universe. This data transmission will be done more rapidly and efficiently than is possible using conventional radio links in use today. The Oerlikon engineers had devised a special experiment in which they set up a laser link between the islands of La Palma and Tenerife in the Canary Islands. The transmission unit was modified in such a way that the conditions on the 144-kilometer stretch between the islands exactly reflected those that would prevail on a 1.5 million kilometer link through space. This was achieved primarily by reducing the emission aperture of the laser to a diameter of less than half a millimeter in order to weaken the light signal.
The Oerlikon team installed the transmission unit in a container beside the Nordic Optical Telescope at an altitude of 2400 meters on Roque de los Muchachos, the highest mountain on La Palma in the Canary Islands. Because of the unusually clear air, this is an ideal location for optical experiments. The receiver terminal was situated in the Optical Ground Station (OGS) of the European Space Agency (ESA) on Tenerife. A breakthrough was achieved at noon on Wednesday as experts from Oerlikon Space succeeded in establishing a laser link between La Palma and Tenerife. In the course of the experiment, they achieved transmission rates of over 10 Mbit/sec. At this speed, it would take a mere two seconds to transmit the entire text of the Bible. The data rate would also be sufficient to transmit three digital television programs simultaneously.
The distance of 1.5 million kilometers simulated on the Canary Islands is equivalent to the distance between the Earth and Lagrange points L1 and L2. These mark specific positions in space at which it is particularly advantageous to place space telescopes. Equipped with laser terminals, telescopes such as these will in future be able to transmit far greater quantities of observation data to Earth than is possible by radio today. Laser communication could also be used for transmitting data to Earth during future missions to the moon—Zurich, Switzerland
