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Laser for Satellite to Satellite Communications

Posted by michael on from the doubles-as-death-ray dept.

heby writes: "Last night ESA successfully tested the first laser link between two satellites (SPOT 4 and Artemis). SPOT 4 is supposed to serve as a data communications relay between Artemis and the receiving station in Toulouse. The link is running at 50Mbps and the two satellites are currently orbiting at 832km and 31000km respectively.
According to ESA "The main challenge in establishing an optical link between satellites is to point a very narrow beam with extreme accuracy to illuminate the partner spacecraft flying at a speed of 7000 m/s." Way to go, ESA!"

4 of 170 comments (clear)

  1. Re:Speed by Anonymous Coward · · Score: 1, Insightful

    this already is the relative speed between thos two.
    Artemis probably is at below 2000m/s while SPOT4 should be at around 9000m/s.

  2. Re:Both going at 7000m/s-1? by imrdkl · · Score: 2, Insightful
    I wondered about this. But the article says that eventually the outer (SPOT) satellite will go stationary, and then initiate up to 5 ordinary uploads per day. I think this is the orbit dependency on the inner (Artemis) satellite? I also dont know what, exactly, the SPOT is taking pictures of, but at 50mb, it can probably get alot of them down to the people who are interested in them. I tried a 20min period using bc(1) and came up with about 10 CDROMS worth SPOT pics.

    Wow. Now, if we could just get laser-pens to be this accurate, then they may actually someday actually replace wooden pointer sticks and fumbling fingers under the overhead lamp trying to make a point during a conference session. heh.

  3. Re:Laser alignment by isorox · · Score: 3, Insightful

    Really? I'm looking at laser systems for broadcasting the campus TV to different buildings. http://www.canon-europa.com/products/network_produ cts/canobeam came up on my search, the network version operates up to 622Mbps, upto 1000m [depending on weather], or 156MBps upto 2000m. It works at 785nm (+-15).

  4. Who cares about linear speed... by javatips · · Score: 3, Insightful

    What amaze me with this kind of PR is that they always use large number to impress people.

    The fact that the linear speed difference between the two satellites (from previous post, I assume that the 7000m/s is the speed difference between the two satellites) is not very important. What is important is the angular speed.

    It is a lot easier to target an object moving at 100Km/h at a distance of 100 meters than to target the same object at a distance of 10 meters.