太赫兹引信面目标散射特性

Multiple time-frequency analysis methods are used to study the echo signal scattering characteristics of two typical area targets (semi-desert grassland and alpine swamp) in Tibet. The results reveal the two-point scattering phenomenon of area targets of the terahertz fuze under the typical angle of falls of 65°and 85°. Based on Geometrical Theory Diffraction(GTD), the area target echo model of a terahertz fuze is established. The echo signal characteristics of multi-point scattering area targets and the application limitations of multiple time-frequency methods are analyzed. To address the problems of the loss of frequency components and the poor frequency component energy concentration in the analysis process, a new wavelet-rearrangement pseudo-Wigner time-frequency analysis method (Mor-RPWVD) is proposed. Distance weighting and time-frequency information fusion are employed to further improve the cross-term interference suppression ability and energy concentration of the time-frequency method. The analysis of the measured data has verified the good time-frequency analysis ability of wavelet-rearrangement pseudo-Wegener (Mor-RPWVD) under multi-point scattering conditions.