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Japan to Deploy Massive Broadband Satellite

Posted by samzenpus on from the connect-anywhere dept.

demachina writes "Japan has announced plans to deploy a massive broadband satellite operational in 2015. It will provide 100 Mbit/sec service to mountains, remote islands and bullet trains along with comm for disaster recovery. Its giant 66 ft. diameter dish is supposed to be able to receive even weak cell phones signals. Of course, the ping times wont be so good."

4 of 274 comments (clear)

  1. Japan has unique opportunity by nokilli · · Score: 3, Interesting

    Being that it's a relatively compact island, I wonder if any consideration was given to a series of satellites in low-Earth orbit.

    Many satellites, all in one orbit that takes each satellite across the nation along the long axis (i.e., north-to-south) should provide continuous coverage with very low latency.

    Given the importance of VoIP it would seem that latency isn't something you can so easily get rid of.
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    Why didn't you know?

  2. Re:Receive Traffic? by Jugalator · · Score: 4, Interesting

    Over here in Sweden, we have for a rather long time now had satellite ISP's for the more remote areas where people can't get DSL and want something better than modem speed. However, it was always very costly and totally not worth the money when put against any other common broadband technology, and I doubt this new Japanese satellite will have very low subscription costs.

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    Beware: In C++, your friends can see your privates!
  3. Satellite ping time myth or fact? by burnttoy · · Score: 4, Interesting

    I've had this argument before and we never came to a sensible conclusion. Personally I still think that high bandwidth satellite data transfer has much merit as long as you can get the satellites up there cheaply enough.

    A geostationary orbit is about 35,000km up. lets call that 50,000km as we might not be right underneath it. Light travels at 300,000km/s so the travel time for a message is ~166ms. multiply by 4 (a->sat, sat->b, b->sat, sat->a) gives ~666ms, the latency of the beast ;-).

    OK, not the greatest but pinging slashdot gives me an average of 349ms from London,UK so it's not as good but then not terrible either.

    I wouldn't want to carry out interactive surgery or try and play a concert with remote players (latency kills live music!) but for just getting hold of and/or disseminating info it's not too bad.

    If the satellite were to be placed in a far lower orbit then latency numbers will drop. I believe this requires spin stabilisers and some sort of engine to keep the satellite from plummeting to Earth though.

    I can't say I'm an expert in satellite orbits and I can't find any more details on the proposed orbit of this project. Anyone care to help me out?

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    Time flies like an arrow. Fruit flies like a banana.
  4. old technologies by freeduke · · Score: 4, Interesting
    If they are going to launch a single satellite, it will be geostationary. This means that latency will be awfull (around 1/4 of a second for a single paquet to reach its destination). So according to this, users will have to define huge TCP windows to be able to reach the maximum throughpup.

    The most interesting technology about satellite communications is based on low orbit satellites networks, but cernaly not on geostationary satellites!

    It must be only an attempt to capture all the radio traffic in Japan from a single dish and use credits dedicated to Research for 'national security'.

    Anyway, this technology is already experimented in the Thalys train, linking Paris to Brussels http://www.thalys.com/be/en/wi-fi/overview