Semi-Global Multi-Frequency Estimation in the Presence of Deadzone and Saturation
D. Carnevale, Alessandro Astolfi · IEEE Transactions on Automatic Control · 2014
A hybrid observer to estimate the frequencies of a signal composed of a finite number of sinusoids and measured through saturation and deadzone nonlinearities is proposed. The observer design exploits the Immersion and Invariance technique combined with a classic high-gain approach, yielding semi-global exponential convergence to zero of the estimation errors. Simulation results are provided to illustrate the effectiveness of the observer.