The Research On Correlation Of Radar Echo In Active Jamming Environment

The advanced and reliable anti-jamming technology which is applicated on radars is a prerequisite for radars to work properly in complex electromagnetic environments,and is also a powerful guarantee for achieving the superior status of electronic warfare.For more than three decades,domestic and foreign scholars have put forward a variety of indicators for measuring radar anti-jamming performance in order to be able to evaluate and quantify radar anti-active interference performance.However,as the radar system and the electromagnetic space environment it faces are becoming more and more complex and changeable,it has not yet formed a unified understanding of the radar anti-active interference performance evaluation and the selection of relevant indicators.In view of the effective construction and flexible configuration of the electromagnetic environment required for existing radar equipment testing,this thesis focuses on the correlation of radar echoes under active interference environment,and reveals the environmental elements of radar active interference and radar echoes.A scientific and effective method is used to study the correlation between various interferences and radar target echoes in an active jamming environment.Based on the strengths of the huge amount of active jamming in the jamming model library and radar target echoes,the interference model can be classified.And grading.This thesis can more quickly and efficiently build the necessary threatening interference environment for all types of radar equipment tests,and can also evaluate or classify the anti-jamming effectiveness of each type of radar.This thesis focuses on the current active interference environment,including suppression interference and deception interference,by extracting various characteristic parameters of the target echo or interference signal in the radar received signal,and then from the signal The processing point of view performs a certain transformation on the characteristic parameters so that the specificity of the signal is clearly differentiated.Then based on feature extraction,the correlations between the above-mentioned active interferences and radar target echoes are analyzed through MATLAB modeling and simulation.First of all,based on the analysis of the status quo of active jamming signals for the suppression of jamming signals,this thesis introduces the correlation analysis method based on frequency domain feature extraction.And on the basis of the feature extraction of the pulse,a complete pulse repetition period feature extraction method was used.Secondly,aiming at deceptive interference signals,by extracting signal features,this thesis analyzes the specificity of feature parameters,and improves or complements existing methods.Aiming at the deficiencies of correlation analysis methods based on time-domain and frequency-domain feature parameters,a correlation analysis method based on Euclidean distance,gray correlation degree,plural resemblance coefficient and time-frequency image-feature was proposed.Under the condition with different SNR and noise reduction,the correlations between the five kinds of deceptive interferences and target echoes were analyzed.The simulation results showed that the correlation analysis methods based on these four feature parameters could distinguish the correlation between the five kinds of interference and the target echoes higher.Finally,this thesis explores and analyzes the factors that affect the correlation between active deception jamming and radar target echo,and initially reveals the most important factors affecting the correlation between the five active jamming jamming and radar target echoes.How these factors affect the change in the correlation between each type of active decoy jamming and radar target echo.