TIME-FREQUENCY DISTRIBUTION ANALYSIS OF SCATTERING FROM WAVE-GUIDE CAVITIES

Time-frequency distributions (TFD) describe a signal in terms of its j oint time and frequency content. In this paper, the TFD analysis of th e electromagnetic scattering from a circular waveguide cavity is inves tigated. Two time-frequency representations, the Wigner distribution a nd the running-window Fourier transform, are applied to the frequency- domain scattering data and the results are compared. For the cavity, p ropagating modes and cutoff frequencies can be determined from the TFD , whereas neither time nor frequency representations will directly pro vide such information.