[maemo-users] Bad experience with N900 onboard GPS.

[From: Aldon Hynes]

Based on the documentation of the GPS software, the GPS can run in four
different modes,

Complementary Wireless Positioning (CWP) - This is based on the location of
the country and/or the GSM base station location.  It does not use the
onboard GPS at all, but depends on the SIM card.

Assisted Complementary Wireless Positioning (ACWP)  - This is similar to CWP
but requires a network connection to get better information about the GSM
base station location

Global Navigation Satellite System (GNSS) - This uses the GPS receiver.  It
does not require a network connection or a SIM card.

Assisted Global Navigation Satellite System (AGNSS) - This uses the GPS
receiver, but gets additional information from a SIM card or Network
connection.  It works basically the same as GNSS, but since it starts with a
good guess at the location is often faster on startup than GNSS.

I had a little fun writing some software for the N900 to track a drive I
took a while ago.  All of the data was extracted using AGNSS and saved to a
file which I loaded into Google Maps.  You can see the map of my trip, as
well as read about the programming I did at

#N900 - My New Gps
http://www.orient-lodge.com/node/3884

(The link to liblocation in the blog post is where you can also read more
information about the various GPS modes)

Aldon
  -----Original Message-----
  From: maemo-users-bounces at maemo.org
[mailto:maemo-users-bounces at maemo.org]On Behalf Of Dawid Lorenz
  Sent: Sunday, February 14, 2010 7:43 AM
  To: Bernard Tyers
  Cc: maemo-users at maemo.org
  Subject: Re: Bad experience with N900 onboard GPS.





  On 14 February 2010 09:12, Bernard Tyers <b at runningwithbulls.com> wrote:

    No, I don't have a connection to the Internet when using Ovi Maps-thats
the exact reason why I use Ovi Maps.

    You shouldn't be expected to use a network connection with an onboard
GPS.

  True, but afaik N900 has A-GPS onboard, which is assisted by supplementary
GPS data downloaded via internet. Without that connection it probably sucks
badly, as you could experience. I am no expert on GPS, but that's how I
understand A-GPS chipsets are working.

  --
  Dawid 'evad' Lorenz * http://adl.pl

  null://I would love to change the world, but they won't give me the source
code
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