Multi-Sine Fitting Algorithm enhancement for sinusoidal signal characterization

In the Multi-Sine Fitting Algorithm (MSFA) based on four parameters sine fitting a problem is the evaluation of the initial condition of the fundamental harmonic frequency, to guarantee the convergence since it is not assured for each initial condition. To overcome this problem, a method devoted to the improved evaluation of initial condition for the MSFA is presented. In particular, the method is based on the algebraic derivative approach in the frequency domain. Numerical and experimental tests confirm the potentiality of the method and the advantages in term of higher accuracy, in comparison with others methods.

Research highlights
► The problem of frequency initial condition estimation for the MSFA is summarized.
► The use of a method based on the algebraic derivative approach in the frequency domain is proposed.
► Numerical and experiments results are shown to characterize the method.