TIME-FREQUENCY ANALYSIS OF SCATTERING DATA USING THE WAVELET TRANSFORM

Scattering data from radar targets are analyzed in the time-frequency domain by using wavelet transform, and the scattering mechanisms are i nvestigated. The wavelet transform used here is a powerful tool For th e analysis of scattering data, because it can provide better insights into scattering mechanisms that are not immediately apparent in either the time or frequency domain. First, two types of wavelet transforms that are applied to the time domain data and to the frequency domain d ata are defined, and the multi-resolution characteristics of them are discussed. Next, the scattering data from a conducting cylinder, two p arallel conducting cylinders, a parallel-plate waveguide cavity, and a rectangular cavity in the underground are analyzed by using these wav elet transforms to reveal the scattering mechanisms. In the resulting time-frequency displays, the scattering mechanisms including specular reflection, creeping wave, resonance, and dispersion are clearly obser ved and identified.