Research On Anti Mainlobe Interference Technology Based On Polarization Separation

With the continuous development of the information war situation,radar plays an important role on the one hand,and on the other hand,it faces the survival problem,which means that radar must effectively deal with the missile attack and electromagnetic interference.For radar,the jamming mode can be divided into sidelobe jamming and mainlobe jamming.Scholars have carried out more in-depth research on the problem of sidelobe interference,but for the problem of mainlobe interference,it started late,and because the interference is located in the mainlobe,it is difficult to suppress the jamming while effectively recovering the target signal.According to the reliable research,the target and interference have obvious differences in the time domain,spatial domain and frequency domain,as well as in the polarization domain.Therefore,it has great potential to study and use polarization information against the mainlobe interference.Based on the difference between the target and the interference in the polarization domain,this paper will separate them,and retain the target signal while effectively suppressing the interference,so as to achieve the purpose of anti mainlobe interference.In this paper,firstly,the polarization and polarization sensitive array of electromagnetic wave are introduced,and a variety of anti-jamming algorithms based on polarization filtering are studied.The performance of these algorithms is discussed through theoretical derivation and simulation analysis,which lays a foundation for the following research.Secondly,taking the uniform linear array receiving model as an example,this paper discusses three traditional non polarization anti mainlobe interference algorithms,including blocking matrix preprocessing,eigen-projection preprocessing,oblique projection spatial filtering,and focuses on the analysis of the anti mainlobe interference performance of each algorithm,pointing out its advantages and disadvantages.In this paper,a joint estimation method of angle and polarization parameters is proposed,which is suitable for any polarization sensitive array,has high performance and low complexity under the condition of few snapshots or single snapshots.Based on the block sparse estimation model of polarization sensitive array,this method uses block orthogonal matching pursuit algorithm to realize the joint estimation of single snapshot spatial angle and polarization parameters in Range-Doppler domain,and further obtains the spatial angle spectrum and polarization spectrum of target and clutter.The results of simulation analysis and data processing show the effectiveness of the parameter estimation method.Finally,the jamming types of radar are introduced,and the characteristics of several typical jamming are analyzed through simulation experiments.After the establishment of different interference models,two mainlobe interference suppression methods based on polarization separation are proposed.Simulation analysis verifies the feasibility of the scheme.