Study On Jamming Technology Of ISAR Compressed Sensing Imaging

Inverse Synthetic Aperture Radar(ISAR)is capable of high resolution imaging of non-cooperative targets and has a wide range of military applications.The high resolution ISAR needs to transmit large bandwidth signals.It brings with the challenges of higher sampling rate of front-end ADC,larger data volume,and more and more difficult real-time processing.Compressed Sensing(CS)theory is expected to break through the above limitations,so it is widely used in ISAR imaging processing.ISAR imaging technology based on compressed sensing has the advantages of high image resolution,less data storage and transmission,etc.,which poses an increasing threat to high-value military targets.Therefore,the research on the jamming technology of ISAR compressed sensing imaging with advance layout has important practical significance and application value.Aiming at ISAR compressed sensing imaging,this thesis starts with the theory and method of ISAR compressed sensing imaging and ISAR deception jamming,and combines the sub-Nyquist sampling,intermittent sampling and forwarding interference with scattered waves.The response mechanism of ISAR to interference signals is studied.The key jamming technology of ISAR compressed sensing imaging is broken through.By combining theoretical analysis,simulation experiment,system realization and test verification,the active deception jamming technology for ISAR compressed sensing imaging was deeply studied.This thesis starts from the mechanism of ISAR compressed sensing imaging.Based on the fully study of the interference object,the formation of realistic and false targets in ISAR compressed sensing imaging processing is studied.In view of these problems,the main contents of this thesis are summarized as follows:Firstly,for the purpose of studying the basic principle of ISAR compressed sensing imaging,a method of ISAR high resolution imaging by using V-FM as the transmitting signal and using dual-channel compressed sensing to dechirp is proposed.Under the same conditions,the image quality of this method is better than that of transmitting LFM signal.In order to solve the problem that ISAR transmitting stepper frequency signals requires a high number of sub-carriers,a high resolution imaging method of sparse coded stepper frequency signals based on compressed sensing processing is proposed.The number of sub-pulses needed to obtain high resolution range images is greatly less than that needed to transmit step frequency signals.Secondly,in view of the problem that the interference mechanism and effect of traditional jamming methods for compressed sensing ISAR imaging are not clear,based on the basic theories and methods of sub-Nyquist sampling and intermittent sampling and forwarding jamming,sub-Nyquist sampling and intermittent sampling and forwarding jamming are the main jamming styles.Combined with the target scattering wave modulation,the ISAR imaging jamming signal model was established,and the characteristics of jamming signal were studied.The technology of sub-Nyquist sampling and intermittent sampling jamming for ISAR compressed sensing imaging is proposed.After the jamming signal is processed by ISAR compressed sensing imaging,the scattering characteristics of the false target formed are very close to those of the real target.The influence of different jamming parameters on the characteristics of false targets formed after compressive sensing processing was analyzed.The jamming effects of jamming signal on ISAR convectional imaging processing and ISAR compressed sensing imaging processing are compared and analyzed.Finally,aiming at the difficulty in carrying out field confrontation tests and the effectiveness of jamming technology cannot be directly verified,an experimental scheme for the verification of the jamming technology of ISAR compressed sensing imaging was designed.The detailed design of the hardware subsystem of the verification system are described and implemented.A kind of improved radar jamming system is developed to build the injection HWIL experimental verification system.By using the experimental verification system to simulate the target echo and generate the interference signal respectively,an ISAR target echo simulation method based on phase precision modulation is proposed and implemented.For the generated target echo,based on DRFM,the engineering implementation methods of sub-Nyquist and intermittent sampling are designed and implemented respectively.The compressed sensing imaging processing is carried out on the upper computer after the jamming data acquisition.By changing the jamming parameters of sub-Nyquist sampling and intermittent sampling,the HRRP and ISAR imaging of different compressed sensing ISAR imaging are get.The jamming effect is analyzed and summarized.The research results of this thesis are verified.