Research On Fast Algorithm For Composite Electromagnetic Scattering From Sea Surface And Target

In recent years,many countries attach great importance to the development and utilization of marine resources.Our country has a large of sea area.While America returned to the Asia Pacific and many states stept in the South China Sea issue along with military equipment and expenditure increased in many countries,which makes the sea battlefield situation increasingly serious.So it is an inexorable trend to improve maritime targets’ reconnaissance and anti-reconnaissance capability,stealth and anti-stealth ability as well as management and control ability of the sea surface battlefield.Meanwhile,enhancing the study of the composite electromagnetic scattering characteristics of the rough sea surface and the target is becoming an important means.In present period,the research in this field focuses on the theory of single target,and the research method are usually the numerical methods.Because the surface roughness of the sea surface,the numerical method used to analysis the sea surface are always requires massive computation and a lot of time.So it is necessary to research the fast algorithm to analysis the composite electromagnetic scattering of rough sea surface.The paper(mainly)studies the electromagnetic scattering of multi-target composite on and above the rough sea surface,and the fast algorithm of the composite electromagnetic scattering of 2D target on 1D rough sea surface.The main work of the paper include:1,The present situation at home and abroad was researched based on the fast algorithm of the composite scattering of the target above the rough sea surface.2,Build the complex model of the single target above the rough sea surface and the multi-target above the rough sea surface.Derived the integral equation and matrix equation of the complex model besides the VV polarization.And then,the electromagnetic scattering characteristics of the complex model was analyzed using the Method of Moment(MOM),and the electromagnetic scattering characteristics under different parameters was analyzed.3,Use the algorithm method-the method of moment in the Kirchhoff approximation to analyze the electromagnetic scattering of the target on and above the rough sea surface.The formulas of the hybrid algorithm in different polarization are derived in detail and the scattering coefficients are calculated.The calculation results using the hybrid algorithm was compared with the method of moment.Results show that the hybrid algorithm can obtain higher accuracy,and reduce the computation time efficiently.And then,the applicability and limitations of the hybrid algorithm was discussed.4,Use the GPU parallel algorithm combined with FDTD to analyze the electromagnetic scattering characteristics of multi-target on and above the rough sea surface.The parallelization program was derived in detail.Then the GPU parallel method was analyzed and verified.The result using the GPU parallel algorithm combined FDTD was compared with the method of moment.Results show that,in some cases,the GPU parallel algorithm combined with FDTD can ensure the accuracy and reduce the computation time.Through the above work,the method of moment and the hybrid algorithm and the GPU parallel combined with FDTD was used to analyze the composite electromagnetic scattering characteristics of 2D target above the rough sea surface.The research of the fast algorithm enriches the research results of electromagnetic scattering and has a certain application value.