[OSM-dev] hacking outdoor GPS devices

[datendelphin]

On 16/04/12 20:26, Mitja Kleider wrote:
> Hello,
>
> I have a few questions regarding outdoor GPS devices:
>
> * Are you satisfied with the available devices? What would you change first?
> * If there was a device with open source firmware, would that be an
> important feature?
I have mostly one concern with available GPS loggers: the varying
accuracy. We don't need the 2-3cm accuracy of a surveyors GPS, but a
little bit more would be helpful. So the two important features would be

 - Show reliably how accurate the position is. Unlike a navigational
GPS, it's of not much use to have quickly a fix which is 100m away. High
sensitivity brings multipath reception which can make a track useless
for mapping. In other words: a mode which only uses a reliable fix.

 - differential GPS. If you want to record some details, positioning a
gps on a known point can give a huge increase in accuracy. This feature
would not be that hard to implement, and I am sure some technical
university would gladly make a project out of it, if we could get access
to the internal measurements of the chip set and not only the fully
processed NMEA data.

Datendelphin