GPS <--> AGPS

[AVee]

On Sunday 08 June 2008 18:07, beren at kabelweb.at wrote:
> On Sunday 08 June 2008 10:41:37 Brad Midgley wrote:
> > Tim
> >
> > >> gpsd has a mode where it listens to both the gps and an online dgps
> > >> source and produces corrected output. See the manpage for gpsd. I
> > >> think you have to have the unit online continuously.
> > >
> > > Does gpsd have control over the various satelite signals? I thought
> > > D-GPS only works before position calculation. If gpsd only gets the
> > > composed position, then it's not possible to do D-GPS.
> >
> > I'm not an expert here, but maybe correction does require more raw
> > data. It might depend on what the protocol is between gpsd and the
> > gps. The gpsd docs don't shed any more light on it. It would be a good
> > question for the gpsd mailing lists.
>
> The problem here is not with gpsd but rather that we might not be able to
> get the required raw satellite measurements out of the Antaris chip due to
> some licence restriction :(
> Not having a Freerunner at hand, I wrote a crude test program for accessing
> the required rxm-raw message of the GPS chip and sent it to Andy Green. The
> results were not encouraging - although I'd love to hear some official
> statement about the license status for the GPS chip before jumping to
> premature conclusions but currently it seems that DGPS will not be possible
> with the Freerunner.

It indeed looks like that, which is a pity, because this could have been a 
feature really setting the Freerunner apart from other devices. 

AVee

-- 
You are only young once, but you can stay immature indefinitely.