Multi-harmonic frequency identification through multistage adaptive notch filter and least squares

The identification and accurate measurement of multi-harmonic frequency components is often required for characterization of various signals and systems. This paper proposes a new method for Multi-harmonic frequency identification based on adaptive notch filtering and least squares fitting. The adaptive notch filtering algorithm is employed for estimation of coarse frequency components. From the initial estimates of the frequency components a least square fitting method is applied to accurately identify the amplitude, phase and frequency estimates.