The effect that jitter and phase noise have on the precision of amplitude estimation of the fundamental and harmonics of a periodic signal is studied. The analysis carried out is applicable to both Three-Parameter Sine Fitting as well as Coherent Discrete Fourier Transform procedures. An analytical expression for the standard deviation of estimated amplitude is presented. It shows that it is proportional to the jitter/phase noise standard deviation (for small amounts of jitter/phase noise) and inversely proportional to the square root of the number of data samples. The expression presented can be used to compute the estimation confidence intervals or determine the minimum number of samples that should be acquired in order to guarantee a given bound on the estimation precision.
Alegria, F. C. (2012). Precision of harmonic amplitude estimation on jitter corrupted data using sine fitting. Signal Processing, 92(3), 807–818. https://doi.org/10.1016/j.sigpro.2011.09.027