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Google map always off by 20 feet; GPS Calibration?

Discussion in 'Android Apps & Games' started by Marc_G, May 14, 2011.

  1. Marc_G

    Marc_G Well-Known Member
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    Hi folks,
    Like the title says, even under optimal conditions my gps derived location in google maps is about 20 feet or so outside the location area. Usually shows me to the NNE of my true location.

    A blackberry bold in my other hand running google maps is spot on within a foot of my location.

    Happens all over reproducibly.

    How to calibrate the thing. I've seen compass calibration but not gps even with the gps status app. Maybe im missing something.

    Please help. Driving me nuts.

    Marc

    Ps. Location settings are all checked on including preferred providers.
     

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  2. Marc_G

    Marc_G Well-Known Member
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    Further information: It's a DroidX on Verizon still running Froyo. Not rooted; nothing exotic about the software environment on it.
     
  3. jimbo78255

    jimbo78255 Newbie
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    Try GPS Averaging, I believe it will help with what you are trying to achieve. Understand, that what you seek requires CPU resource that not everyone requires, so courser readings that use less CPU allow the monster phone to do other monster stuff - like play Radio Margaritaville. :)
     
  4. AngryHatter

    AngryHatter Android Expert
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    GPS was made by the military, they de-tune it for civilian use.
    You wouldn't want your enemy to know exactly where you are.
    You'll never get 100% accuracy.
     
  5. Marc_G

    Marc_G Well-Known Member
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    Hi guys,

    Thinking this may be a Droid X troubleshooting issue more than an application issue, I've started a thread over here:

    http://androidforums.com/droid-x-support-troubleshooting/335615-droid-x-gps-calibration-problem.html

    As for the military/civilian thing... keep in mind my current Blackberry Bold (and the one I had before that... I forget the name) easily gets me within 6 feet of the exact spot, I don't think it's a military/civilian thing.

    My actual location is well out side the "somewhere in this circle" spot on the map... that's the issue. If I were within a 20 foot ambiguity circle, on both devices, fine, but my X is clearly wrong and out of calibration.
     
  6. zerocool79346

    zerocool79346 Android Expert
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    Could it be because you)we) are inside. My phone (DInc) has me across the street and caddy-corner from where I really am, however, I've never known it to be off when I'm outside so I wonder if being within "line of sight" of the satellites might be the cause of accuracy (or lack thereof).
     
  7. Marc_G

    Marc_G Well-Known Member
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    Nope, my tests are all outside in the open, no tall buildings around. GPS status generally says 8/9 satellites locked.
     
  8. RazzMaTazz

    RazzMaTazz Android Expert
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    Wow! Things have changed. Who'da thought that we'd be bummed because a cheap phone is off by 20 feet when locating us on a planet with a surface area of 5.5 quadrillion square feet. :)
     
  9. DenverRalphy

    DenverRalphy Android Enthusiast
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    That changed in 2000 and is no longer true. The reason civilian GPS isn't as accurate today is the result of manufacturing costs. Most civilian GPS devices use a single signal for communication as opposed to the military who use multiple signal communication to filter out transmission errors. As well, most civilian GPS devices are built with cheaper and lower quality hardware to keep manufacturing costs and battery consumption to a minimum.

    That being said, the OP says his DX is off by 6 meters (about 20 feet), which actually isn't too shabby for civilian GPS, but isn't the best either. My Dinc when I'm outdoors usually gets to within 1 or 2 meters.

    [edit]Forgot to add, that while the GPS is no longer degraded for civilian use by default, the military does still retain the ability to intentionally degrade civilian GPS in selective locations. So if the US President is visiting your local area, don't be surprised if your GPS device doesn't seem to be as accurate as it normally is.
     

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