Electromagnetic (EM) scattering properties from the ship wakes on the two-dimensional (2-D) perfect electric conductor (PEC) sea surfaces are studied by utilizing the small-slope approximation (SSA) theory. Considering the limitations of using the ideal plane EM wave incident upon a rough sea surface of the limited size, the expressions of the scattered field and scattering amplitude are derived by utilizing the modified tapered incident field. Based on a simplified segmented ocean spectrum model, the bistatic and monostatic normalized radar cross sections (NRCS) from the PEC sea surfaces with and without ship wakes are calculated, respectively. Meanwhile, the variation of scattering coefficient as scattering angles is given and compared under different polarization states. The results show that the scattering from the PEC sea surfaces with ship wakes is evidently different from that without them in bistatic and monostatic scattering. This provides a basis to extract ship wake characteristics. Also it shows that the SSA is a very effective analysis method to deal with the EM scattering from the rough sea surface. Finally, the effect of different tapered factors on backscattering coefficient is discussed, and it is concluded that an artificial reflection from the boundaries and a scattering upwarping from low-grazing incidence can be avoided just when the tapered factor is relatively smaller. This gives the theoretical basis for the analysis of EM scattering characteristics of ship wakes on the PEC sea surface.
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