| When calculating the scattering problems related to random rough surfaces,the numerical methods have good computational accuracy.However,with the increase of the unknown quantity of the target,the demand for the computing resources becomes larger and the computation efficiency is reduced.The main works of this dissertation are listed as follows:First,several analytical approximate methods for electromagnetic scattering of random rough surfaces are analyzed.Analytical approximate methods are KA,SPM and SSA.Then the rough surface is regarded as an infinite plane,and the scattering of the above target is analyzed by Green's function in the half space.In actual conditions,the rough surface has the height of fluctuation,and then based on the rough surface Green's function,the composite scattering of the random rough surface and the target is calculated.The calculation of the rough surface Green's function is time-consuming.Finally,the electromagnetic scattering of the compound target is analyzed on the basis of SSA and the calculation speed is improved.Finally,the target single station scattered field data are acquired from the traditional sweeping frequency and angle to perform two-dimensional ISAR imaging.Modeling and imaging analysis of electromagnetic scattering characteristics for random rough targets.Firstly,the modeling and calculation of simple random rough standard objects are described.For the actual complex and electrically large random targets,the target scattering is divided into coherent and incoherent scattering.The surface microstructure of the target surface is analyzed by the rough surface scattering theory.And it can realize the scattering of target.Finally,for the time-consuming problem of calculating the monostatic field of a target with a certain frequency band and angle in the traditional imaging process,a ISAR imaging formula based on the SBR method was deduced.Two dimensional ISAR imaging of complex random rough targets is realized. |
PDF Full Text Request