Study On High Efficient Jamming And Effectiveness Evaluation Method Of Missile-borne Spotlight SAR

Synthetic Aperture Radar(SAR)has many advantages,such as high resolution and strong anti-jamming capability.The application of missile-borne SAR in the sea battlefield environment is gradually increasing,and the research on the method of SAR jamming to the sea is becoming more and more important.In this dissertation,the working principle ? mode and imaging algorithm of missile-borne spotlight mode SAR are analyzed.Based on the above analysis,the weak points of missile-borne spotlight mode SAR are proposed,which are based on the aspects such as working environment,signal processing,mode characteristics and target motion characteristics.And then the corresponding jamming strategy is developed.Then,the jamming method of missile-borne spotlight mode SAR to the sea is studied from three aspects: signal processing,sea battlefield environment and moving target characteristics.Finally,Performance evaluation is studied.The main research contents and achievements are as follows:1.Research on the range shift-Azimuth Doppler jamming method.This method is based on the characteristics of the LFM signal,and the azimuth signal can also be approximated to the LFM signal.It is researched through the Doppler modulation in azimuth and frequency shift in range.Theoretical analysis and simulation results illustrate their validity;2.Research on the clutter modulation jamming which is based on the special working environment of the missile-borne SAR.Give the different clutter models and propose the modulation method.Theoretical analysis and simulation results show that the jamming method can achieve the effect of suppressing the variable size and multi-dimensional matching coverage;3.Research on the method of missile SAR jamming for moving targets.Firstly,the influence of the typical motion on the SAR imaging is analyzed,and the theoretical derivation results are given.Then,on the basis of the above analysis,the jamming method for the moving target can be proposed through modulating the false motion information after the stationary target echo.Theoretical analysis and simulation results show that the method can achieve the effect of jamming the moving target.4.Research on range-azimuth combined modulation jamming method for moving targets.The method is based on the time-frequency coupling characteristic of LFM signal and the motion characteristic of the moving target,The jamming result of the range-azimuth joint modulation for the moving target can be achieved by modulating the fixed frequency of the intercepted target echo and modulating some false motion information.5.The evaluation system of SAR jamming efficiency is summarized.The objective evaluation of several interference methods in this paper is carried out by using the correlation indexes such as mean,variance,similarity of structure,correlation coefficient and so on.