Investigation on Micromotion Characteristics of Trimaran and Corner Reflector Based on the Motion of Six Degrees of Freedom

A trimaran is an advanced ship with high hydrodynamic performance, the study of its electromagnetic (EM) scattering characteristics in marine environments is of value to the detection of trimaran ships. This paper presents a method to evaluate the effect of corner reflectors on the scattering field of a trimaran. Based on the Reynolds-averaged Navier-Stokes (RANS) equations, the interpolation wave-making method (IWMM) is proposed for the prediction of the six degrees of freedom (6-DOF) motion of the trimaran and corner reflectors. This method takes into account the viscous effect of the flow field and the complexity of wave motion, which can be applied to the seakeeping prediction of ships under different sea states. Second, the influence of corner reflectors on the backscattering characteristics of the ship-sea scene is demonstrated by the geometrical optics and physical optics (GO-PO) algorithm. Finally, the Doppler spectrum characteristics of the composite scene are presented by the standard spectrum estimation method, which provides a reference for radar detection and identification of ships in the microwave band.