Filtering of frequency modulated signals embedded in α-stable noise using robust DFT forms

A task of frequency modulated (FM) signal filtering by means of robust DFT is considered. It is shown that in the case of non-Gaussian noise with symmetric heavy-tailed pdf a standard DFT cannot efficiently suppress outliers that contaminate the signal. Three robust DFT forms are described and the procedure adaptive to tail behavior based on the myriad estimate for deriving real and imaginary spectral components is proposed. It is demonstrated that the use of the described and proposed approaches leads to considerable improvement of signal estimate in comparison with techniques based on standard DFT. Such improvement (MSE reduction) is provided for a wide range of parameters of noise with symmetric α-stable distribution.