Vaisala WMT703 - Wind Direction Coasting; Vector Averaging; Figure 9 Example of Wind Direction Averaging

Chapter 3 ______________________________________________________ Functional Description
VAISALA _______________________________________________________________________ 31
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Figure 9 Example of Wind Direction Averaging
Wind Direction Coasting
Accurate wind direction measurement requires that the wind speed is at a
sufficient level. If you enable wind direction coasting, WMT700 does not
calculate wind direction when the wind speed drops below the selected
wind direction coasting threshold. The last calculated direction output
remains until the wind speed increases enough to reach the threshold and
WMT700 returns to normal operation.
Vector Averaging
When vector averaging has been selected, WMT700 calculates wind
speed and direction averages by adding up each x velocity and y velocity
measurement from the averaging time and then dividing the sum by the
number of measurements. WMT700 converts the resultant average x
velocity and average y velocity to polar direction and magnitude, which
returns the wind direction average in degrees and wind speed average in
the chosen units.
If the data acquisition system requests data before the initial averaging
time completes, the sensor returns the most recent complete measurement
data.