Doppler Spectrum of Backscattered Field from Time-Varying Sea with a Low-Flying Small Target Above It

In this paper, the Doppler spectrum of backscattered echoes from moving target above time-varying sea surfaces is investigated by utilizing the quasi-stationary algorithm, i.e., approximating the time-domain problem by repeatedly implementing the frequency-domain method. In order to fast and accurately solve the composite scattering problem of time-varying sea surfaces with a Low-flying small target above it, a hybrid algorithm of Kirchhoff approximation (KA) and method method-of-moments (MoM) is utilized in this paper for analyzing the Doppler spectrum signatures. The effect of the speed of flying target on Doppler spectrum signatures of a low-flying small target above time-varying sea surface is investigated in this paper.