[time-nuts] OT - GPS and North

[Florian Teply]

Am Saturday 21 November 2009 15:05:12 schrieb iovane at inwind.it:
> Does a stationary (not in motion) GPS receiver know where the North is?
>
> As far
> as I can understand, it doesn't, isn't it?
>
Umm, as far as i understand it, a single receiver with a single 
omnidirectional antenna (at least with rotational symmetry around the 
vertical axis) can't know where north is.
IF you just so happen to have a more clever setup, this indeed becomes 
possible. Basically, a GPS receiver happens to not compute his own location 
but the one of his antenna. So if you happen to have a receiver with enough 
correlators and stuff to properly connect two (or more) antennas and 
calculate positions for both, it could actually deduce true north. Bearings 
get better the more space you have between the antennas and the more 
averaging you can apply. Time for averaging doesn't seem much of an issue in 
a truly stationary setup, so just try to maximize separation of your 
antennas.

HTH,
Florian