6.9.4 SMOOTHING DATA
It is not always possible to eliminate all noise, especially with very low level sensors, but noise looks terrible when plotted and can raise doubts about otherwise excellent data. There are two simple ways to eliminate noise from the data:
1.Apply a moving average to the data if you want to retain the same apparent accuracy.
2.Remove the information from the noisy range. For example, if a 12 bit A/D converter is at +/- 5 volts (10 volts full scale) then one LSB = 10 / 4096 = 0.00244mV. If your system is inducing +/- 0.007mV of noise (+/- 3 counts), round all the readings by +/- 3 counts. In this way the reading's value reflects the true accuracy of the system.
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