The European Space Agency (ESA) has successfully demonstrated for the first time a datalink connection between two satellites using a laser beam as the signal carrier.
The test was performed between ESA's Artemis satellite and the French space agency CNES Earth observation satellite Spot 4 using the Semiconducor Intersatellite Link Experiment (SILEX). The laser datalink transmitted images taken by Spot 4 in real time to the image processing centre in Toulouse, France, via Artemis. The link was established four times, and was maintained for up to 20min.
Astrium-built SILEX comprises two optical terminals - Pastel on board Spot 4 and Opale on Artemis. The system allows optical high-speed - 50mbit/s - data transmission by laser link. SILEX connected the two satellites which were travelling at relative speeds of several thousand m/s and were separated by more than 30,000km.
SILEX is capable of transmitting in real-time high-definition video images at 50mbit/s. The optical technology, which speeds up the transfer of information, uses smaller antennas and less power than conventional RF links and provides a minimum risk of interference with other communication systems.
Source: Flight International
