Research On Characteristics Of Clutter In The Composite Scene Of A Moving Target And Sea Surface

Our country is a large maritime country.The rational development and utilization of marine resources is of great significance to our country's national defense security and safeguarding maritime rights and interests.In order to promote the development of our country's marine industry,it is necessary to strengthen the theoretical research and technological development of marine electromagnetic technology.The research on the composite scattering of rough sea surface and target is particularly important,which is of great significance for civil applications,military defense security,remote sensing detection and so on.Especially in the field of microwave remote sensing detection,mastering the clutter characteristics of the composite scene of sea surface and target is the prerequisite for improving the target detection.Therefore,the hybrid high-frequency algorithm is employed to investigate the clutter characteristics of composite scene of the actual dynamic sea surface and moving target in this thesis.The main research contents are as follows:1.Based on the common sea spectrum model,the three-dimensional dynamic sea surface is constructed combing the two-dimensional ocean energy spectrum ELH spectrum and the Longuet-Higgins direction function.In addition,the geometric model of three-dimensional dynamic sea surface for different wind directions and wind speeds are generated with the use of Monte Carlo method(linear filtering method).2.The basic principles of Semi-Deterministic Facet Scattering Model(SDSFM)is presented,and the effectiveness of SDFSM is verified by comparing the simulated scattering coefficient of sea surface with the measured data.Then based on the SDSFM,the sea surface scattering coefficients for different frequencies and wind speeds are calculated.And the influence of different parameters on the backscattering coefficient of sea surface is analyzed.Furthermore,the amplitude distribution and spatial-temporal correlation characteristics of sea clutter are introduced.The scattering echo sequence of dynamic sea surface under different radar parameters and sea conditions are generated by SDFSM,and the amplitude distribution and spatial-temporal correlation characteristics are analyzed.3.The electromagnetic scattering model of target is constructed based on SBR.Then the SBR is combined with SDFSM to establish the composite scattering model of the sea surface and complex targets(missiles,ships).The composite scattering characteristics of sea surface and target under different sea conditions are analyzed.Meanwhile,the spatial amplitude distribution and spatial-temporal correlation characteristics of the sea surface and ship target composite scattering under different conditions are discussed.4.The composite scattering echo model of the dynamic sea surface and moving targets(missiles,ships)is established.The scattering echo data of the sea surface and moving targets with different parameters are simulated.Then the sea surface is divided into areas,and the clutter statistical characteristics for different areas are analyzed.The effect of target motion parameters on the spatial-temporal correlation characteristics is further studied.