[OSM-talk] Choice of GPS for bicycle use in London

[Thomas Walraet]

Martyn Welch a écrit :
> 
> If I remember correctly, GPS satelites are not geo-stationary, so the exact 
> number of visible satelites are likely to vary a little over time. I guess 
> this may have a strong effect on accuracy in highly built up areas and would 
> explain differing results at different times.

Yes, and you can forecast how many satellites are going to be visible, 
for example on this page :
http://mappinghacks.com/projects/gpscal/query.shtml