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China Earth The Military

China Begins Using New Global Positioning Satellites 168

cswilly writes with the news that China's satellite navigation system, called Beidou, has been successfully activated. "With ten satellites now, 16 in 2012, and 35 in 2020, China is making damn sure they are independent of the U.S. military's lock on GPS. According to the article, 'Beidou, or 'Big Dipper,' would cover most parts of the Asia Pacific by next year and then the world by 2020.'" The BBC also has slightly more detailed coverage.
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China Begins Using New Global Positioning Satellites

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  • Re:Not surprising (Score:5, Interesting)

    by InterestingFella ( 2537066 ) on Tuesday December 27, 2011 @12:00PM (#38503378)
    China has a huge amount of their own infrastructure, so this isn't really surprising. Unlike U.S., China likes to do everything themselves. This also means you're not dependent on other countries like the U.S. is. What you don't understand is that China thinks long term, and everything they've done will grant them the leading country status some day, probably even within 10-15 years, especially when considering how much U.S. and EU are struggling now after thinking only short term financial gains.
  • Old news? (Score:5, Interesting)

    by Bananana ( 1749762 ) on Tuesday December 27, 2011 @12:06PM (#38503434)
    we have car navigation systems that use Beidou for some time now (maybe less than a year).
  • by tylernt ( 581794 ) on Tuesday December 27, 2011 @12:30PM (#38503706)

    From what I can tell from the Wikipedia article, Beidou is an active system where the "client" sends data to the satellites in orbit. It makes perfect sense for the Chinese though, because now they can track where their users are -- something not possible with the passive US system since the receivers only receive and can't transmit any data back. In short, Big Brother Beidou always knows where you are.

    Seems like an active system has a huge disadvantage, though. You can DOS the satellites by pointing an antenna at each satellite and jamming their uplink frequencies, knocking out the whole system for everyone, everywhere. In the US system, you can only jam local terrestrial reception and anybody over the next hill won't be affected.

  • by caseih ( 160668 ) on Tuesday December 27, 2011 @12:38PM (#38503806)

    Something I didn't realize until recently is that in the northern latitudes (Canada, northern US), GPS coverage has occasional small gaps in it. My John Deere dealer was saying that in some areas every few days about 6pm (happens to be that time in those areas) GPS coverage drops below 1 meter accuracy levels, and in those areas GPS guidance on farm machines becomes unusable for about an hour or so. As well sometimes a satellite goes offline for maintenance. As agriculture is becoming very reliant on GPS (hence John Deere lobbying in washington against LTE usage of adjacent frequencies), this is a problem. Because of this John Deere now uses GPS and GLONASS together to get better coverage. When Galileo provides coverage, it will use those signals too. The point is, more GPS systems simply improve reliability for everyone, if the Chinese allowed western use of their signals.

  • by ChronoFish ( 948067 ) on Tuesday December 27, 2011 @12:39PM (#38503820) Journal
    Would be possible to get a more accurate position if a receiver combined the various GPS systems - as a kind of check/balance. For non-military use the GPS systems introduce inaccuracies. Is there an algorithm that would bring the resolution down from 10 meters to 1 meter or less?

    -CF
  • by BorelHendrake ( 1496471 ) on Tuesday December 27, 2011 @12:49PM (#38503966)
    When we were traveling across the United States, there was about 45 minutes of our trip through Utah where we were not receiving GPS signals. I believe it happened in the early afternoon. Fortunately there were not turns involved during that portion of the trip.
  • Re:Not surprising (Score:5, Interesting)

    by Maxo-Texas ( 864189 ) on Tuesday December 27, 2011 @01:56PM (#38504730)

    China owns a trillion dollars worth of US debt.

    With the dollar dropping by half in value, they've lost 500 billion dollars in purchasing power.

    They do this to keep products cheap enough to sell to the US so they population has work and won't get antsy. They build empty cities for similar reasons (well actually I can't comprehend exactly why they build empty cities and empty buildings- it seems goofy).

    China being a huge country is not an asset, it's a liability.

    They do have a good legal lock on assets- but many of those assets are only rare at the current prices. As soon as rare earth prices go up 50%, millions of tons of rare earth can come on line- including a huge mine in the US.

    About the time they stop building empty cities, the demand for copper and other building materials is going to drop through the floor.

    --

    The US leadership class appears to have lost it and descended into greed.

    --
    The true threat to the work is not china or the US but the corporations and the top 1%. And it's almost certainly two decades too late to do anything about it.

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