Radar Scattering From the Composite Ship-Ocean Scene: Doppler Spectrum Analysis Based on the Motion of Six Degrees of Freedom

In general, a ship moves with translation and rotation under the action of water. The investigation of the motion of ship is useful for the scattering echo simulation. In this communication, we firstly focus on modeling and simulation for the motion of ship in six degrees of freedom in two dimensional (2-D) sea surface based on the program public domain strip method (PDSTRIP). Then, some further simulations and the influence of various parameters (such as the polarization, incident angle and wind direction) on the Doppler spectrum are analyzed to prove that the facet-based asymptotical model is an effective model to investigate the EM scattering from the 2-D sea surface. Finally, in consideration of the motion of ship in six degrees of freedom, the radar echo and Doppler spectrum of the dynamic composite maritime scene are then studied based on the proposed specular reflection weighted four-path model. It is found that the motion of ship has the most significant effect on the RCS and Doppler spectrum.