GPS <--> AGPS
Joerg Reisenweber
joerg at openmoko.org
Fri Jun 6 01:25:10 CEST 2008
Am Do 5. Juni 2008 schrieb Lally Singh:
> AFAIK, the AGPS allows you to upload additional information into the
> onboard correlator (the CPU that does the actual location calculations
> for GPS) to enhance the accuracy over what you get with simple
> satellite triangulation.
It's about reducing TTFF, not increasing accuracy [1]. Basically you tell the
receiver which sats it should expect, so it doesn't have to check all
possible "channels" and "download" the data from sat (AFAIK). See ephem and
alm in uBlox paper.
[1] Increasing accuracy is differential-GPS, where you have a reference
receiver at known position, so you can tell pos of 2nd relative to ref in
sub-meter accuracy.
Also see: http://wiki.openmoko.org/wiki/Hardware:AGPS which I found just after
typing the above.
/j
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 194 bytes
Desc: This is a digitally signed message part.
Url : http://lists.openmoko.org/pipermail/community/attachments/20080606/e7aa4034/attachment.pgp
More information about the community
mailing list