Study Of SAR Deception Jamming Method Based On Modulation Characteristics

With the ability of SAR (synthetic aperture radar) to obtain information gettinghigher and higher, it has a great significance to research a more accurate SAR deceptionjamming method to protect important military targets information from being stolen byenemies through the SAR system. As most of the existing SAR deception jammingmethods still stay on the level of generated similarity lower false target signal, it isdifficult to achieve a purpose of real deception jamming. Therefore, the researches onthe extraction of the fine features of the SAR typical target and deception jammingalgorithm based on modulating and achieving real deception jamming to enemyadvanced SAR imaging system are of great significance to our army modernization ofnational defense technology development.This dissertation firstly introduces the basic principles of SAR and thecharacteristics of SAR images, and then analyses the mechanism of deception jamming.At the same time, the effect picture of the deception jamming is obtained by simulations.Finally, the dissertation summarizes the characteristics of SAR deception jamming andthe existing difficulties.By analysis of the typical military target datas such as tanks, buildings and bridgesand combining the target properties, this dissertation uses CFAR segmentation methodwhich is based on statistical model to segment the target area and make a featureextraction and selection. Through simulation experiments, this dissertation gives adetailed analysis of the characteristics and finally obtains several typical characteristicswhich can illustrate SAR image target area features. They can be viewed importantfeatures to deceive the scene and assess the deception scene effect.On the basis of feature extraction, the dissertation researches a method of SARtarget region of strong scattering center distribution generation based on the abstributedscattering center model and proposes a deception jamming algorithm based onmodulation characteristics. The SAR spoofing scene is formed by simulationexperiments; the effectiveness of the algorithm is verified; At last, the deception thescene fidelity is evaluated by calculating the distance of two times. The dissertation has studied the influences of several typical radar parameter erroron deception jamming imaging.Through analysis and simulation experiments show that:center frequency error, the Doppler frequency rate and velocity error will affect thepositioning accuracy of deception scene. The theoretical analysis and simulationexperiments give the following results: the FM slope error affect the focusing effect ofthe deceptive scene imaging and lead to decreasing of the peak and broadening of themain lobe.Finally, the range of allowable error of different bandwidth chirps isanalyzed.