Harmonic extension of an adaptive notch filter for frequency tracking

Adaptive frequency tracking is useful in a broad range of applications, and many schemes have been introduced in the recent years for that purpose. Starting from the observation that, in some situations, an harmonic component is also present in the signal of interest, we propose in this paper to extend frequency tracking to harmonic frequencies in order to improve convergence properties. We apply this idea to a specific adaptive frequency tracking algorithm and obtain through theoretical analysis and computer simulations the performance gain of this new scheme.