Removal in Instrumentation and Measurements
For DC measurements 1/f noise can be particularly troublesome as it is very significant at low frequencies, tending to infinity with integration/averaging at DC. At very low frequencies, you can think of the noise as becoming drift, although the mechanisms causing drift are usually distinct from flicker noise.
One powerful technique involves moving the signal of interest to a higher frequency, and using a phase-sensitive detector to measure it. For example the signal of interest can be chopped with a frequency. Now the signal chain carries an AC, not DC, signal. Accordingly, you can filter out the DC by using AC-coupled stages. This filtering of DC also attenuates the flicker noise. You then use a synchronous detector, that samples the peaks of the AC signal, which are equivalent to the original DC value.
Read more about this topic: Flicker Noise
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