Research On SAR Target Distribution And Deceptive Jamming Technology

SAR plays an important role in electronic warfare because of its advantages of allweather,all-time,strong penetration and high resolution.In order to protect our important military information,it is particularly important to research SAR deceptive jamming technology used to conceal our targets and confuse the enemy.At present,most of the SAR deception jamming technologies produce false target signals with low similarity and poor real-time performance,which can not achieve good deception jamming effect.To this end,the following research has been done in this thesis :Firstly,this thesis describes the basic principle of SAR,the mechanism of deceptive jamming and the geometric features,scattering center model,gray level features and texture features of SAR images.Then,the principle of speckle and statistical distribution model of SAR image are emphatically introduced,and the typical SAR scene is reconstructed using statistical distribution model.The reconstruction results show that the method can not meet the reconstruction of high-similarity scene.Then,this thesis introduces the traditional deceptive jamming mechanism of SAR for distributed targets,and uses this method to simulate and analyze the deceptive of targets and scenes.It is found that there are some problems in the final deceptive jamming image,such as edge and shadow distortion of false targets,high energy of false targets or scenes.Then the problems of traditional deceptive jamming of SAR are analyzed.In order to improve the similarity of SAR deception jamming,this thesis studies the deception jamming method of SAR,which makes full use of the incremental scattering distribution of real and false scene information.Firstly,the method is studied under the assumption that the radar parameters and the real scene are known.Before the simulation,some steps in the simulation are introduced in detail.False scenes are generated by image quilting technology.False scenes are screened from two aspects of logical coincidence and high similarity.Template library is built by extracting texture primitives of scenes to improve the speed of generating false scenes.Then,the deception jamming method of SAR with incremental scattering distribution is used to simulate the target,and the method is compared with the traditional method from the angle of recognition.The results show that the deception jamming effect of incremental scattering distribution is better.Then the deception jamming of the scene is simulated,and the better jamming effect is obtained,but the negative value is more when calculating the increment of scattering distribution.Therefore,this method is improved by modulating the amplitude and contrast of the false scene to reduce the negative value in the increment of scattering distribution.The simulation results show that the improved method has better deception jamming effect.Finally,some problems in deceptive jamming of SAR are studied in this thesis.The main purpose is to improve the similarity of deceptive jamming of SAR.Firstly,the method of how to get the real scene when the real scene information is unknown is studied,and the simulation and comparison of deceptive jamming are carried out.The edge problem in actual deception jamming is analyzed and dealt with,and good results are obtained.Then,the deception jamming equation is deduced and analyzed.Starting from the traditional and scattering distribution increment deception jamming methods of SAR,the relationship between the signal-to-clutter ratio and the transmitting power of jammer is studied and analyzed in deception jamming of target,and the target jamming strategy under different background is formed.Starting from the deceptive jamming in scene,the relationship between the interference signal ratio and the transmitting power of jammer is studied,and the jamming strategies in different false and real scenarios are formed.