Synthetic Aperture Radar Anti-jamming Technology Research

Synthetic Aperture Radar (SAR) is a kind of active microwave imaging radar. It can all-weather,all-day and timely get ground images of wide region and has fine penetrability to vegetation and ground.. SAR is pretty important to resources exploitation and military reconnaissance and has been widely used in diverse fields of civil and military.This paper delves into the research of SAR anti-jamming technology from two sides. First, author proposes the definition,classification of SAR anti-jamming and the standard of evaluating anti-jamming methods. Then on one hand, author makes researches of anti-jamming against pulse jamming,Gauss white noise jamming and radio frequency noise jamming from the side of signal processing. Author exercises much signal processing knowledge of time-domain sliding window accumulation,wavelet analysis, time-frequency analysis and linear prediction and carries out many simulation experiments. On the other hand, author proposes the anti-jamming methods of using a SAR similar to double-base radar and modulating the amplitude,the phase of emission signal and changing the frequency modulation slope from the side of changing SAR system model. Likewise author makes corresponding simulation experiments.Some valuable conclusions are summarized by theoretical analysis and simulation experiments : From the side of signal processing, pulse jamming can be deleted by the method of time-domain sliding window accumulation and can be restored by interpolative prediction.; Gauss white nose can be attenuated while jamming disperse point-target by the method of time-frequency analysis in time-frequency domain.; Radio frequency noise jamming can be deleted by the method of average range frequency spectrum and notching in frequency domain. From the side of changing SAR system, a SAR similar to double-base radar can avoid all noises, and modulating the amplitude,the phase of emission signal and changing the frequency modulation slope are fairly good anti-jamming methods.