National Physical Laboratory

The use of the Allan deviation for noise and drift measurements in radiometry applications

Further Information

Published: 8 March 2012

Authors: Andrew Levick, Martin Dury, Jane Ireland, Emma Woolliams and Nigel Fox

Related: Optical Radiation & Photonics

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All measurement systems have a resolution limited by random fluctuations (noise) or by variations in parameters with time (drift). The Allan deviation statistical method allows different noise and drift types to be readily identified at various timescales.

We have used the Allan deviation method to measure the noise and drift in the power of a supercontinuum laser with and without power-stabilisation feedback control.

The Allan deviation method clearly shows that the feedback control removes drift. The random uncertainty in the mean stabilized laser power, determined using the Allan deviation method, is <0.01 % for averaging times longer than 100 s.

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Last Updated: 14 Aug 2017
Created: 8 Mar 2012


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