It is clear that a barometer is more accurate in measuring altitude than GPS. However is it true that the barometer improves GPS position accuracy?
Would be a GPS device and a GPS+barometer device equally accurate if we didn't look at the altitude?
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Sign up to join this communityIt is clear that a barometer is more accurate in measuring altitude than GPS. However is it true that the barometer improves GPS position accuracy?
Would be a GPS device and a GPS+barometer device equally accurate if we didn't look at the altitude?
The science of sensor fusion provides, by the combination of multiple, seemingly redundant measurements, a reduction of variance in the combined measurement. Basically speaking, for independent, identically distributed noise processes, the signal to noise of combined $n$ measurements is increased by the factor of $\sqrt{n}$.
And in fact, commercial INS (Inertial Navigation Systems) include among the accelerometers, GPS recievers, and gyro sensors, an aneroid barometer, all of which feed into a Kalman filter resulting in a very accurate estimate of position, velocity and three axis attitude.
Examples include the LN100 fom Litton and Honeywell's EGI (Embedded GPS in INS) systems