Improved Time-frequency Filtering Using an Stft Analysis-modification-synthesis Method
نویسندگان
چکیده
Time-frequency representations provide a convenient method for analyzing signals whose frequency content changes with time, and speciically those signals with components that overlap in time and/or frequency. In this paper we suggest a technique for optimally concentrating components of a signal in the time-frequency plane via a particular choice of analysis window for the short-time Fourier transform (STFT), as well as an eecient method of optimal least-squares synthesis of a component of interest from the STFT. Using the described synthesis method in conjunction with an optimally localized STFT yields a very accurate estimate of a component that may not otherwise be separable from other components or noise in the signal.
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