×

Discussion Board

Results 1 to 12 of 12
  1. #1
    Registered User
    Join Date
    Mar 2003
    Location
    Luttenberg (Netherlands)
    Posts
    577

    GPS accuracy (E75)

    Hi,

    we have written an application for tracking & tracing. For testing purposes I have been driving around a little. The locations are displayed in a website. It occurred to me that the GPS positions are not very accurate.

    The E75 has also an application called "GPS Data". If you use the tab "Position" there is a field "Accuracy". If you drive around the "Accuracy" goes between 10 - 120 meters. That's quite shocking.

    - What is the expected accuracy you could achieve with a GPS enabled phone?

    For information: Assisted GPS, Integrated GPS and Network based position methods were enabled.

    BR,

    Rene
    Rene Heuven
    Inmote - Creative Smartphone Solutions
    Web: www.inmote.com
    E-mail: rene@inmote.com

  2. #2
    Nokia Developer Moderator
    Join Date
    Sep 2004
    Location
    Tampere, Finland
    Posts
    11,359

    Re: GPS accuracy (E75)

    With an acuracy of +-100m I would expect that you have indeed the GPS chip providing the data so the other positioning technologies should not impact you at all. Run a test with them disabled if you wish ...

    The accuracy of the GPS readings is variable and it is expected to be so. This is why the APIs provide you information about data's accuracy for each reading. I don't know what the "normal" values should be, I don't even know what normal should mean since the accuracy of GPS depends on so many factors which are rather impossible to control.
    -- Lucian

    If you are not yet a DVLUP member it is time to correct that mistake :) Click here to join: http://www.dvlup.com/lucian/Invite

  3. #3
    Registered User
    Join Date
    Apr 2005
    Location
    Barcelona
    Posts
    1,678

    Re: GPS accuracy (E75)

    Those values are rather normal, at least in my experience. You might want to apply some filtering to it, in order to smooth the output.

  4. #4
    Registered User
    Join Date
    Mar 2003
    Location
    Luttenberg (Netherlands)
    Posts
    577

    Re: GPS accuracy (E75)

    Hi David/Itomuta,

    thanks for the answers. So in principle this means using internal GPS of a phone gives pretty low accuracy for GPS positions. If I would like a better accuracy I should search for external GPS devices and connect them through Bluetooth?

    Is there any information about the exact GPS hardware which is used in specific Nokia phones? Is it possible to get some information what the manufacturer technical specifications are concerning GPS accuracy, etc?

    BR,

    Rene
    Rene Heuven
    Inmote - Creative Smartphone Solutions
    Web: www.inmote.com
    E-mail: rene@inmote.com

  5. #5
    Registered User
    Join Date
    Apr 2005
    Location
    Barcelona
    Posts
    1,678

    Re: GPS accuracy (E75)

    Hi Rene,

    Besides the chipset, it will also depend on the way it's built into the device. I don't know if there's any public information about which chipset is used on different devices (probably some blog will have some non-official info about it) but besides external BT, you could also use some other beacon-based positioning, like wlan..

  6. #6
    Registered User
    Join Date
    Mar 2003
    Location
    Luttenberg (Netherlands)
    Posts
    577

    Re: GPS accuracy (E75)

    Hi David,

    thanks for the suggestion about WLAN. However, our intention is really to implement a track&trace solution which can be used to track vehicles on the road. So GPS will be the only viable technology.

    BR,

    Rene

    BTW: It was nice to meet you at OSIM in Amsterdam. Supprise for me. You answered already a lot of question here on the forum. Good luck with your new international venture .
    Rene Heuven
    Inmote - Creative Smartphone Solutions
    Web: www.inmote.com
    E-mail: rene@inmote.com

  7. #7
    Registered User
    Join Date
    Apr 2005
    Location
    Barcelona
    Posts
    1,678

    Re: GPS accuracy (E75)

    Hi Rene,

    Sorry, forgot that bit in your original post.

    Thanks for your wishes, and it was nice meeting you there as well :-)

  8. #8
    Registered User
    Join Date
    Jan 2008
    Posts
    38

    Re: GPS accuracy (E75)

    I have to disagree with you on the accuracy of internal receivers. I use my N95 for things like geocaching (using this trimble geocache navigator application) and the accuracy in the open is a few meters. Even with building/treecover I still find the accuracy to be within say 20 meters, certainly not 100 meters.

    That said, I have been playing around with the Symbian location API. Does anyone understand the parameters of the signal quality and where they come from? I know a returned position includes real values for horizontal/vertical/height/time accuracy, but within what limits do they operate? If anyone can point me to some documentation about this then that would be appreciated.

    Is it perhaps possible to create an observer (much like say MConnectionMonitorObserver does to monitor network connections) that reports the status of the GPS signal?

  9. #9
    Registered User
    Join Date
    Oct 2009
    Posts
    7

    Re: GPS accuracy (E75)

    A Standard GPS chip would provide an accuracy of 5 - 10 m. before Pres Clinton the US Military used to add a error that made a GPS signal accurate to 100m 80% of the time.

    This error has been removed, and over the next few years chips will have the choice of the US GPS, the Russian equivalent, and the Europeans are currently placing a new system in space.

  10. #10
    Registered User
    Join Date
    Jun 2009
    Posts
    8

    Re: GPS accuracy (E75)

    Where did do the test. In a city, or outside?

  11. #11
    Registered User
    Join Date
    Mar 2003
    Location
    Luttenberg (Netherlands)
    Posts
    577

    Re: GPS accuracy (E75)

    Hi JarekP,

    this test was done outside a city on a rural country side area. The route did include some places where the vehicle was driving below trees (that had leaves - it was still autumn) and the wetter rainy (cloudy skies). Nonetheless I was expecting better accurary. It would be good if some documentation about the type/make of the internal GPS receiver for E71 (and other phones) was available.

    BR,

    Rene
    Rene Heuven
    Inmote - Creative Smartphone Solutions
    Web: www.inmote.com
    E-mail: rene@inmote.com

  12. #12
    Registered User
    Join Date
    Jun 2009
    Posts
    8

    Re: GPS accuracy (E75)

    In this case I would not expect the accuracy to stay low at all times. Most navigation software does average the positions anyway and "sticks" to the original road even if the quality of the position is not best.

Similar Threads

  1. GPS Accuracy
    By lokesh_kumar_s in forum Symbian
    Replies: 10
    Last Post: 2011-11-10, 11:01
  2. JSR-179API provider reset to stop GPS location activity
    By nicholso in forum Mobile Java General
    Replies: 15
    Last Post: 2009-02-06, 11:33
  3. GPS accuracy
    By swelef in forum Symbian
    Replies: 2
    Last Post: 2009-01-30, 10:29
  4. Replies: 0
    Last Post: 2008-05-12, 09:57
  5. Bluetooth GPS simulator for j2me phone
    By vgps in forum Mobile Java Networking & Messaging & Security
    Replies: 2
    Last Post: 2007-02-09, 04:30

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
×