Research On Imaging And Anti-Jamming Of Missile-Borne Spotlight Mode SAR

Synthetic aperture radar is a high-resolution imaging radar which is widely used in modern military and scientific field.Due to its unique synthetic aperture principle and other related techniques,it has a high resolution in azimuth and distance.Spotlight mode missile-borne SAR has the advantage of high-resolution imaging of small scenes,so it is the focus of research in radar-related fields.In this dissertation,the main contents is the imaging algorithm of spotlight mode missile-borne SAR and anti-jamming measures,which are introduced as the follow:1.Study on the two kinds of spotlight mode missile-borne SAR imaging algorithm: Polar Format Algorithm(PFA)and Frequency Scaling Algorithm(FSA).Firstly,according to the geometric model of the spotlight mode missile-borne SAR,the correlation function expression of radar echo signal is derived.Then,based on the idea of PF algorithm and FS algorithm,the imaging theory of the echo signal is deduced.Finally,the two imaging algorithms are simulated by Matlab,verifying the effectiveness of the imaging algorithm.2.Study the deception jamming imaging of the spotlight mode missile-borne SAR.According to the principle of active spoofing interference,the radar is disturbed and the interference echo signal function form is deduced based on the interference model.Based on the PF algorithm and FS algorithm,the distance spoofing interference,azimuthal spoofing interference and two directions joint fraud jamming for false imaging are studied.Finally,we use Matlab to simulate the three kinds of jamming false targets,and verify the effectiveness of the jamming measures.3.The anti-jamming technology of the spotlight mode missile-borne SAR is studied.By analyzing the generation mechanism of active spoofing interference andstudying the difference between real target echo and false target echo,and the random phase anti-jamming method and frequency-modulated polarity agility changeanti-jamming method are adopted,and a new anti-jamming methodcombining two anti-jamming algorithms is proposed,which has the advantage of the both of therandom phase anti-jamming methodand frequency-modulated polarity agility changeanti-jamming method.Finally,we use Matlab to simulate the anti-jamming method,and verify the effectiveness of anti-jamming for active spoofing interference.At the end of this dissertation,the research work is summarized and suggestions are made for the next work.