Time-frequency subspaces and their application to time-varying filtering

Abstract

A method is presented for time-frequency filtering, i.e., filtering with pass and stop regions directly defined in the time-frequency plane. The filtering is performed by projecting the input signal on a time-frequency signal subspace corresponding to the time-frequency pass region prescribed. This projection takes the form of a linear time-varying filter where the filter's impulse response is constructed using Wigner distribution signal synthesis techniques.