- #1
Roughmar
- 6
- 0
I am afraid that this is either too specific and\or that this is in the wrong forum (if the latter is the case, if moderators could change this, I'd appreciate :).
I'm trying to do an application that uses the GPS data that comes from NMEA files.
On a particular sentence (RMC) there is a value indicating "speed". After looking about it, I found a place that described this speed as in "Speed over ground, Knots".
I have two doubts regarding this value:
Exactly what does it mean? Is it the speed having the ground as a reference, or a projection on the ground, making it a 2D speed (not caring about differences in the altitude.)?
Also, how accurate is it? How is it calculated?
I'm trying to do an application that uses the GPS data that comes from NMEA files.
On a particular sentence (RMC) there is a value indicating "speed". After looking about it, I found a place that described this speed as in "Speed over ground, Knots".
I have two doubts regarding this value:
Exactly what does it mean? Is it the speed having the ground as a reference, or a projection on the ground, making it a 2D speed (not caring about differences in the altitude.)?
Also, how accurate is it? How is it calculated?