Research On SAR Anti Deception Jamming Technology Based On Waveform Optimization

Synthetic Aperture Radar（SAR）is an active microwave remote sensing system.Compared with optical imaging,it is not affected by light and climatic conditions and can work in any weather at any time,so it has received extensive attention in civil and military fields.SAR is easily affected by jamming systems.Deception jamming can generate deception targets with low power,which is the research focus of jamming technology.Especially the modern jamming function based on digital radio frequency memory can quickly modulate and forward the intercepted radar detection signals,form false targets on SAR images,and interfere with real target recognition and judgment.The SAR anti-spoofing jamming technology based on waveform optimization refers to optimizing the design of the radar waveform,combining a certain transceiver strategy,and then through signal processing,so that the real target can be imaged correctly,and the false target can be defocused to achieve the purpose of anti-spoofing jamming.In the current research on anti-spoofing and jamming technology,waveform design is one of the key research objects.From the perspective of waveform optimization,this thesis studies LFM-phase encoding hybrid waveform,continuous phase jitter waveform,adaptive initial phase,and two-dimensional joint anti-jamming technology in range and azimuth.The main contents are as follows:1.The optimization method of LFM phase coded hybrid waveform is proposed.By integrating the autocorrelation function and cross-correlation function of phase coded signal,reasonably designing the objective function,the optimization model of LFM phase coded hybrid waveform is established,which improves the orthogonality of LFM phase coded hybrid waveform.On the premise of ensuring the imaging quality,the signal to interference ratio tolerance of anti-interference is improved.2.The optimization method of continuous phase jitter waveform is proposed.Taking the signal peak sidelobe ratio,integral sidelobe ratio and peak cross-correlation ratio as the optimization factors,the objective function is reasonably designed,and the optimization model of continuous phase jitter waveform is established.The imaging performance and orthogonality of continuous phase jitter waveform are improved,and the signal-to-interference ratio of anti-interference is improved.3.The optimal setting method of azimuth random initial phase is studied.By extracting the azimuth compression process and aiming at increasing the degree of signal mismatch,the optimal setting model of azimuth random initial phase is established,which weakens the shadow strip formed by false target in azimuth and improves the antiinterference ability in azimuth.4.The two-dimensional joint anti-jamming technology in range and azimuth is studied,and the principle of two-dimensional anti-jamming technology is analyzed.Through simulation experiments,the anti-jamming capabilities of one-dimensional and two-dimensional anti-jamming technologies are analyzed and compared,and the improvement of the two-dimensional anti-interference ability is verified.In this thesis,the above method is verified by theoretical analysis and experimental simulation.The results show that the above method can effectively filter out deceptive jamming targets,and the tolerance of Signal to interference ratio is increased,and the anti-jamming ability is improved.