Low Probability Of Intercept Radar Waveform Design And Performance Analysis

Since radar has great application in military field, various of electronic interferences even anti-radiation missile have also been large applied. Low Probability of Intercept (LPI) radar appears in this environment. The research of LPI technology make radar can fight against with all kinds of electronic interferences and anti-radiation missile attacks effectively,so as to improve radar survival rate in complicated electronic environment.This paper starts from the present developing situation of LPI radar, and have deduced the LPI factor expression according to the LPI principle, analyzed the influence factors of LPI factor, also discussed the relevant measures to implement low intercept technology. The study of this paper mainly has two aspects:waveform design and performance analysis.First,this paper analyzes the inherent and related characteristics of frequency modulated continuous wave, phase encoding signal and their combined signal respectively, it shows that both frequency modulated continuous wave and phase encoding signal can get big timewidth and bandwidth product with the same detecting range as pulse radar with lower peak power. Secondly, according to the fuzzy function and complexity of signal structure, linear frequency modulated fuzzy graph is inclined blade, and doppler is not sensitive, but it exists range doppler coupling; Fuzzy graph of phase encoding signal is close to ideal "pushpin" type,it doesn’t exist mutual coupling fuzzy. This paper focus to derive the fuzzy function expression of LFM+Barker and MAC+P4. The simulation shows that combined signal has a "plate nail" type fuzzy graph, with higher resolution, complicate forms and hard to be recognized and interfered by scout.Due to the low intercept is a "relative" concept, in the light of different intercept receivers, this paper analyzes the receiver type, sensitivity and intercept distance,and proposes the low utilized factor of LPI radar signal, simulates and compares utilized factors of LFM,Barker,LFM+Barker signal and P4,MAC,P4+MAC signal using solution of linear modulation and circulation spectral density methods.It shows that solution of linear modulation can get high processing gain by processing LFM signal,and LFM+Barker combined signal’s utilized factor is smaller than LFM and Barker. Circulate spectral density method can extract carrier frequency, bandwidth and other parameters of signal.The processing gain of combined signal intercepted by scout is the least, so the utilizated rate of combined signal is lower than single signal.