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Government Funded Atomic Clock On a Chip

Posted by samzenpus on from the let's-get-small dept.

An anonymous reader writes "Today most applications that require accurate atomic clock readings — from sorting separately routed telecommunications packets to timing simultaneous demolition charges — usually refer to signals from global positioning systems (GPS). For applications where GPS is unavailable, such as indoors, underground, undersea or on the battlefield where electronic jamming is present, large, heavy, power hungry hardware atomic clocks were needed. Now an atomic clock-on-a-chip is available that is the result of 10 years of government-funded research and development. The chip is not cheap — $1,500 — but it costs less than conventional atomic clocks and the price is sure to go down as manufacturing gears up to meet demand from military applications."

9 of 134 comments (clear)

  1. frequency hopping and better navigation. by LWATCDR · · Score: 4, Interesting

    I can think of two to uses off the top of my head. The first is for really fast frequency hopping radios. The rate at which they can hop from one to the next has got to be in some measure limited to how accurate the clock they use is.
    And the next one would be improved navigation. You could use these with ground stations and provide extremely accurate navigation and you could use more powerful transmitters so they would be harder to jam.
    Now if they could uses these to put a time signature on every radio, tv, and cell tower You could improve navigation in areas where GPS doesn't work so well. Like in buildings. cites with lots of tall buildings, or areas with lots of tree cover.

    --
    See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
    1. Re:frequency hopping and better navigation. by Arlet · · Score: 3, Informative

      Having a local known good time would reduce the GPS error by itself. It would also allow 3D position to be determined with 3 visible satellites instead of 4.

    2. Re:frequency hopping and better navigation. by Andy+Dodd · · Score: 3, Interesting

      Yup. One of the barriers to postprocessing is local clock inaccuracy - so having a local atomic clock would be great for survey-grade GPS units.

      And as you stated - if receiver clock offset is 0, then you don't need to solve for it, and can get 3D position with 3 sats instead of 4. The actual effect of an inaccurate clock on the error is harder to determine - I have a feeling that with a reasonable quality local crystal oscillator (good enough not to cause cycle slips in the measured carrier phase, etc.) it's insignificant compared to ionospheric error and RF noise in the pseudoranges, along with multipath. The new L2C civilian signal will help some of these issues.

      A highly accurate local clock might also make dead reckoning in a blockage situation (urban canyons, tunnels, etc) and signal reacquisition after blockage goes away faster.

      --
      retrorocket.o not found, launch anyway?
  2. Re:Thanks but no thanks! by ThunderBird89 · · Score: 4, Informative

    Umm, not all smoke detectors are of the electrostatic variety. There are types that use an IR laser to check for particulates and smoke based on occlusion.

    Also, for some fun facts, see The XKCD Radiation Dosage Chart! If you worry about smoke detectors, you'll be surprised at how much radiation you get from living in a brick house...

    --
    Hyperbole: I use it liberally!
  3. Re:Thanks but no thanks! by _0xd0ad · · Score: 3, Funny

    This orange represents your head. This tinfoil represents... well, tinfoil. This microwave represents... well, just watch.

  4. Re:Thanks but no thanks! by ByOhTek · · Score: 4, Informative

    (1) most atomic clocks don't use anything radioactive, they use vibrations of cesium atoms. Given how up tight you are, something that vibrates might be useful to you.
    (2) don't eat bananas.

    --
    Self proclaimed typo king, and inventor of the bear destroying coffee table (patent not pending).
  5. No! not Symmetricon! by NixieBunny · · Score: 3, Interesting

    Symmetricon has been buying up all the other precision clock makers, and is now a monopoly. They can and do charge whatever they like for such products.

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    The determined Real Programmer can write Fortran programs in any language.
  6. Re:Thanks but no thanks! by nabsltd · · Score: 3, Funny

    So the laser simply asks the cesium what time it is.

    ...millions of times per second. Sort of like the world's most annoying child:

    "What time is it? Are we there yet? What time is it?"

  7. Re:OXCOs are cheap and common right now by ThunderBird89 · · Score: 4, Funny

    As for time dilation of any kind, there are maybe five people (all of them Doctors of some sort) who care in anything other than a merit-badge sort of way.

    Who's one of them?

    --
    Hyperbole: I use it liberally!