Research On Intra-Pulse Analysis And Target Detection Based On Radar Signal

Intra-pulse analysis and target detection of radar signals are two important functions of the radar system,but also the technical basis of its subsequent signal analysis and processing.In order to further improve the performance of the radar system and reduce the difficulty of the subsequent analysis and processing of the radar signal,the thesis carries out the intra-pulse analysis and target detection technology research based on the radar signal.On the basis of effectively recognizing the radar signal modulation mode,the problem of pulse arrival time and carrier frequency estimation in the pulse description word is studied emphatically.The realization process of intra-pulse analysis and target detection is designed in detail,and the simulation experiment is carried out based on the radar signal receiver processing system software.The main research results and conclusions are as follows:1.The author studied the modulation recognition of radar signal.Based on the analysis of the frequency-modulated signals and phase-coded signal,the author used frequency spectrum 3dB bandwidth of the two signals to realize inter-class classification of the above-mentioned signals.Afterwards,according to wavelet ridge,the author extracted instantaneous frequency characteristic sequence of radar signals and realized intra-class subdivision for frequency-modulated signals and phase-coded signals.The simulation results show that when the SNR is greater than 3dB,the accuracy rate of inter-class classification of FM signal and PSK signal is more than 90%.When SNR is more than 0dB,the accuracy rate of intra-class subdivision for FM signal and PSK signal are all about 100% steadily.2.The thesis focuses on the estimation of the intra-pulse parameters of the radar signal with pulse arrival time and carrier frequency.Aiming at the pulse arrival time,a high accuracy estimation method based on triangular wavelet is proposed.The method is applicable to the conventional rectangular envelope signal,LFM signal and PSK signal.The simulation results show that the proposed method's estimated accuracy is more than 20% higher than the reference algorithm for the pulse arrival time.Aiming at the problem of carrier frequency estimation of LFM signal,a DPT+FRFT two-dimensional interpolation algorithm is proposed.The simulation results show that the algorithm still maintains a small estimation error in the case of shortening the computation time of 50%.For the PSK signal carrier frequency,a method based on improved wavelet ridge fit adaptive MAT is proposed.The simulation results show that the relative estimation error of the algorithm can be less than 60 ppm when SNR is about 4dB.3.The author studied the target detection technology based on the radar signal.The overall design of the receiver system of the external radiation source radar signal processing is proposed.The realization process of the intra-pulse analysis subsystem and the target detection subsystem is designed in detail.The simulation software of the external radiation source signal processing receiver system is compiled and fully simulated experiment.The results show that the intra-pulse subsystem and the target detection subsystem meet the expected target and the engineering application requirements,.Finally,the accurate detection of the target is realized,which proves the higher application value of the system scheme.