Howtosignalprocessing
- How do you calculate Allan variance?
- What is Allan variance and how is it used?
- How is Allan deviation measured?
- What is Tau in Allan variance?
How do you calculate Allan variance?
Interpretation of value
Allan variance is defined as one half of the time average of the squares of the differences between successive readings of the frequency deviation sampled over the sampling period.
What is Allan variance and how is it used?
Allan variance is a statistical analysis tool for identifying various noise types that exist in a signal. Developed in the mid-1960s, the Allan variance was used to measure the frequency stability of precision oscillators. Later, this technique was applied to other areas as well.
How is Allan deviation measured?
The beat frequency method is the standard method to measure Allan variance, or more precisely to measure the frequency deviation of the DUT from the frequency standard. The total power at the respective offset frequency is read from the spectrum analyzer display.
What is Tau in Allan variance?
Allan variance is used to measure the frequency stability of oscillation for a sequence of data in the time domain. It can also be used to determine the intrinsic noise in a system as a function of the averaging time. The averaging time series τ can be specified as τ = m/fs.
