Adaptive interference removal based on concentration of the STFT
We propose a new method for adaptively removing noise and interference from a signal. In this method unwanted components are removed from the short time Fourier transform (STFT) surface, and the clean signal is estimated by integrating the modified STFT with respect to frequency. Isolation of the signal and interference components is facilitated by a concentration process based on the phase of the STFT differentiated with respect to time. The concentrated STFT is a linear representation, free of cross terms and having the property that signal and interference components are easily recognized because their distributions are more concentrated in frequency. Interference removal may be accomplished by removing unwanted components from the concentrated STFT, and the clean signal may be estimated by integration of the modified concentrated STFT. We demonstrate the advantages of the proposed method over conventional methods.
short time fourier transform adaptive filter spectral subtraction instantaneous frequency channelized instantaneous frequency time-frequency signal estimation reassignment