Extraction of signals buried in noise Part II: Experimental results

In the second part of this series, we report application procedures and performances of "modified frequency extent denoising (MFED)" and "constant frequency extent denoising (CFED)". It is shown that MFED and CFED work independently of the nature of noise (colored or white, Gaussian or not) and locations of its spectral extent. Denoising is achieved without using a priori information on the signal and any sort of averaging in the time or frequency domain. Moreover, CFED depicts better white denoising performances than the modified periodogram method. Denoising ability of CFED applies with much better performances than bispectrum estimation and wavelet denoising when spectra of experimental random processes (Doppler velocimetry signals) and colored noise (Gaussian or not) superimposed to them, overlap. It is shown that CFED is a powerful denoising and analysis tool of buried random signals occurring in real world situations.

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