LPI Radar Signal Design

The war in today's world is the confrontation of electronic technology,radar can detect and track the target,play an important role in the electronic warfare,and the radar is facing some threats include to electronic interference,stealth technology,low altitude penetration and anti-radar missiles,in order to improve the viability of the radar,low intercept technology came into being.The design of the signal waveform is critical to improve the low intercept performance of the radar,MCPC signal is introduced into the field of LPI radar because of its large time-bandwidth product,excellent immunity to interference,and good low intercept performance.This paper introduces the traditional LPI radar signals,including phase coded signal,LFM signal and mixed modulation signal,analyzes their detection performance and low intercept performance,and points out the shortcomings.Then the source and signal structure of the MCPC signal are introduced,due to the signal has a large PMEPR,this paper analyzes the influence of carrier frequency weighting on PMEPR in detail.In order to analyze the detection performance of the signal,this paper deduces the fuzzy function of MCPC signal and analyzes the influencing factors of the autocorrelation function.Aiming at the problem of design of MCPC signal parameters,two LPI MCPC signals with good performance are designed with fuzzy function,PMEPR,and low intercept performance.The first is to optimize the problem that the PMEPR of MCPC signal based on chaotic two-phase code is too large by the time domain iteration clipping method.The second is to use the properties of GCS to encode the frequency domain data of the MCPC signal into a GCS,then carry out the carrier frequency amplitude weighting.The simulation results show that the optimized MCPC signal based on chaotic two-phase code is similar to that of the MCPC signal based on GCS,and when the SNR is-5d B,the enemy can not find the existence of the signal by time frequency analysis.Compared with traditional LPI radar signal,P4-based ISMCPC signal and COCS MCPC signal,these two LPI MCPC signals have better detection performance and low intercept performance.