Modeling Simulation And Characteristic Analysis Of Radar Chaff Interference Echo

Chaff interference,especially the emergence of new chaff jamming weapons,has seriously affected the performance of radar seekers to detect and identify targets.In order to improve the ability of the anti-ship radar seeker to accurately strike the target,it is necessary to fully "know" the chaff and grasp the echo characteristics of the chaff,and select new features against the chaff interference from different dimensions.Based on the modeling and simulation of radar chaff interference echo,the paper focuses on the chaff interference faced by the anti-ship radar seeker,and systematically studies the chaff echo from multiple dimensions such as time domain,frequency domain and polarization domain.The research also designs a foil strip echo model system software for simulation and characterization functions.The research results of the thesis can provide certain theoretical reference and technical support in the research of new radar seeker system design and anti-interference technology.The specific work of the thesis is as follows:Firstly,the chaff echo is modeled and simulated.The physical properties of chaff are studied from the aspect of chaff geometry.The rationality of the research object and its parameter selection is expounded.Based on the kinematics modeling and electromagnetic modeling of a single chaff,the chaff echo signal is obtained according to the chaff echo generation mechanism and the chaff cloud statistical model.The results show that the chaff echo can reflect the influence of environmental parameters,self-parameters and radar parameters on the echo characteristics of the chaff.The accuracy of the chaff echo meets the requirements of the subsequent research of the paper;Secondly,the characteristics of the chaff echo are analyzed in the time domain and the frequency domain.In the time domain,the statistical properties of the chaff echo amplitude and the average RCS statistical properties were studied.In the frequency domain,the characteristics of the spectral width feature are analyzed.The influence of the incident angle of the radar,the incident wavelength of the radar,the standard deviation of the moving speed of the chaff,and the standard deviation of the rotational speed of the chaff on the spectral width feature are discussed.And the separability measure function is used to quantitatively analyze the separability performance of the spectral width feature in distinguishing between ships and chaff.The results show that the echo power spectrum width can be used as a feature quantity to distinguish between true and false targets,and the feature quantity is mainly affected by the standard incident wavelength of the radar and the moving speed of the chaff.Thirdly,the characteristic analysis of the chaff echo is performed in the polarization domain.Aiming at the problem that the existing feature quantity has a poor recognition effect against the new vertical polarization chaff,this paper improves the existing feature quantity and gives the new feature quantity.Then the theoretical variation law of new feature quantity with radar incident angle,radar incident wavelength and chaff attitude is analyzed,and a large number of echo simulation data are sampled to verify the theoretical law of new feature quantity with parameter variation.And the divisibility measure function is used to quantitatively analyze the separability performance of the new feature quantity in distinguishing between ship and chaff.The research results show that the modified new feature quantity can be used as the feature quantity when distinguishing between true and false targets,and the corresponding feature quantity has corresponding value range with the change of parameters.Finally,based on the MATLAB GUI interface,a chaff interference echo modeling simulation and characterization software system was developed.And introduced the design idea of the system software,the function of each module and the operation instructions.The results of the study are helpful to the experimenter's operations and related research.