Design Of Radar Waveforms For Anti Smart Jamming

Because of the flexible forms and good performances of smart jamming, it has gradually become an important research direction of the radar jamming technology, it has both the characteristics of suppressing and deception jamming, posing a serious threat to the radar system.Basing on LPI and parameter agility, we designed some radar waveforms, which are capable of anti-smart jamming. The thesis consists of three parts as below:(1)The basic principle and classification methods of suppressing and deception jamming are described, furthermore, we studied the mechanism of smart jamming, then analyzed the jamming method and jamming effect of pulse convolution jamming and noise convolution jamming.(2)Aiming at designing LPI radar waveforms, the thesis began with the Interception Factor, and designed the waveforms with low peak power, large timewidth and bandwidth product, complex modulation method to improve the LPI performance of radar. Firstly, the thesis introduced four commonly used radar waveforms, designed two kinds of combined signals, and analyzed their LPI performances. Secondly, we researched the basic principles of OFDM, the basic OFDM radar waveform and two kinds of Multicarrier Phase Coded(MCPC) waveforms are analyzed. It proves that combined modulation and MCPC are more promising for future application.(3)In order to design the parameter agility waveforms, we designed the phase coded waveform using two chaotic sequences(Logistic and ICMIC) and analyzed their antijamming performances under different conditions. Then phase jitter and center frequency agility radar waveforms are designed based on the linear frequency modulation(LFM), The study found that the center frequency agility radar waveform had better anti-jamming performance. At last, we designed a radar waveform using both center frequency agility and chaotic phase coded methods, significantly enhanced the LPI performance.