32. Frequency Estimation Techniques Associated Problems: Threshold Performance Key idea: The performance degrades when peaks in the noise spectrum exceed the peak of the frequency component. Dotted lines in the figure show the probability of this occurring.
33. Frequency Estimation Techniques Associated Problems: Threshold Performance [continued] For the multi-harmonic case, two threshold mechanisms occur: the noise outlier case and rational harmonic locking. This means that, sometimes, ½, 1/3, 2/3, 2 or 3 times the true frequency is estimated.