Composite EM scattering and Doppler spectral analysis for time-varying Sea surfaces and a target above it

Recent years have seen a large number of efficient analytical and numerical techniques for exact calculations of rough surface and target composite scattering. In this paper, an efficient hybrid method combining physical optics (PO) with physical optics (PO) is used to research on the electromagnetic (EM) scattering from a PEC target above a dielectric sea surface, and the scattering of a static target on the time-varying sea surface is calculated. Then the average Doppler spectra of backscattered signals obtained from such simulations are compared for different incident angles and polarizations, it shows a broadening of the Doppler spectra for composite model.