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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."

11 of 274 comments (clear)

  1. Re:Good job by Anonymous Coward · · Score: 5, Funny

    It's not really important anyway. Normal users don't use the ping command or even heard of it.

  2. Japanese in space? by Anonymous Coward · · Score: 5, Funny

    I thought Space was owned by America? I can't see George standing for this, he'll use his death star to shoot it out the sky.

  3. Re:Receive Traffic? by malchus842 · · Score: 5, Informative

    DirecWay (from DirecTV) offers satellite return service - no phone line necessary. I used it for about 6 months some time ago (when this area was total broadband hell, as opposed to only being partial broadband hell). It does work, but some major caveats:

    • When it rains hard, forget about using it until the storm passes
    • When it snows, you have to clear the dish regularly (or use a cover)
    • Latency is tremendous - basically forget online gaming and VoIP

    But, if it's your only option, it's great. Seriously - in the same situation, I'd use it again

  4. Outdated by the time it starts working? by My+Iron+Lung · · Score: 5, Insightful

    In 2015, ten years time, this might not be such a great speed? Although it's quite fast now, and will probably still be reasonably useful in the future, it might be about as popular as dialup is in my city (not very). Who knows what zany download speeds will be the norm in the future, across electrical wires or otherwise.

  5. 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.

    --
    Beware: In C++, your friends can see your privates!
  6. 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?

    --
    Time flies like an arrow. Fruit flies like a banana.
  7. Large ping? by TheRaven64 · · Score: 4, Informative

    A geosynchronous satellite orbits at a height of approximately 38,500,000m. Light travels at a speed of approximately 300,000,000m/s. It therefore takes light approximately 250ms to make a round trip. This might be sub-optimal for gaming, but its about the ping time I remember from a modem. You might run into some problems with TCP rate limiting though - it's probably best to run some non-TCP protocol over the satellite link.

    --
    I am TheRaven on Soylent News
    1. Re:Large ping? by FrostedWheat · · Score: 5, Informative

      You also have the round trip of reply packet to consider, so double that to 500ms. Then you have to add the normal internet latency, so say on average the lag will be about 550ms to 650ms. Not horrible but worse than dialup.

  8. Re:erm? by marx · · Score: 4, Informative

    Japan apparently has their own satellite launching infrastructure. Otherwise I think NASA and ESA both help with launching commercial satellites, it doesn't seem to be a big deal anymore.

  9. Nope. by Gordonjcp · · Score: 5, Informative
    A large dish catches a large amount of signal. Think about how much rain will be caught in an empty swimming pool in 10 minutes, compared to how much rain will be caught in an empty wineglass.


    The beam width is dependant on a lot of things. You can adjust the focus of the transmitter to turn the beam into a big fuzzy spot.

  10. 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