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TheoH Bias-removal Method



David A. Howe, Jennifer A. Taylor, Tiffany Tassett


A version of Theo1 variance, called TheoBR variance (BR for ''bias-removed'' relative to the Allan variance), is constructed. This relative bias correction is applied over a range of the longest-recommended Allan tau values for a given data run. The oH deviation ('H' to indicate a hybrid combination of The oBR and Allan deviations) is the Allan deviation in short term and switches to the Th\^ e } oBR deviation in long term. In the presence of non-integer-power-law and mixed noise types, the approach is as effective and less cumbersome than past approaches, and requires little, if any, a priori knowledge or judgment of data being analyzed. The substantially gained properties of The o1 at large tau , to 50 % beyond the longest possible tau using the Allan deviation alone, can be obtained without Allan bias. Long-term frequency stability can be obtained in essentially one-third less time. For example, the two-month stability can be obtained with three months of data, rather than four months of data that is usually required for such a point.
Proceedings Title
Proc. 2006 Freq. Cont. Symp.
Conference Location


Howe, D. , Taylor, J. and Tassett, T. (2006), TheoH Bias-removal Method, Proc. 2006 Freq. Cont. Symp., , USA, [online], (Accessed March 2, 2024)
Created June 4, 2006, Updated October 12, 2021