No question here, just a discussion.
I 'm currently toying with a GPS unit, through an Arduino Duemilanove.
I read its datasheet and manual, and I noticed the Datum parameter, which reconciles the GPS measurements with map topography of a certain area.
From what I gathered, a map's Datum is "linearizing" the flat map over a certain area, to minimize the fault due to the earth's spherical shape.
So I though it would be a good idea to change the GPS's Datum to Greece. BAM! 40m error on the measurements. I returned to the default Datum and I hardly get any error, maybe the expected 1.8m one.
That makes me think, what's the point of the Datum parameter for my GPS unit?
I 'm currently toying with a GPS unit, through an Arduino Duemilanove.
I read its datasheet and manual, and I noticed the Datum parameter, which reconciles the GPS measurements with map topography of a certain area.
From what I gathered, a map's Datum is "linearizing" the flat map over a certain area, to minimize the fault due to the earth's spherical shape.
So I though it would be a good idea to change the GPS's Datum to Greece. BAM! 40m error on the measurements. I returned to the default Datum and I hardly get any error, maybe the expected 1.8m one.
That makes me think, what's the point of the Datum parameter for my GPS unit?