Research On Clutter Modeling And Target Detection Based On Non-cooperative Moving Radar Emitter

Non-cooperative radar emitter target detection technology is always a subject of concern in the field of radar target detection.Along with the development of the era,complicated electromagnetic environment and the effective implementation of the modernization of concealed weapons environment is gradually increasing trend,non-cooperative radar emitter system works using outside sources,and has low cost,fast stealth detection,and the advantages of preventing electromagnetic interference and anti stealth,provides the non-cooperative radar target detection is relatively convenient,expand the search scope of the basic theory and equipment.However,due to clutter,data registration,direct wave power,signal uncertainty and delay caused by the moving state of radiation source,it brings many difficulties and challenges to target detection.For radiation source caused by moving clutter complications,which may lead to a difficult target detection,this paper puts forward the clutter modeling based on non-cooperative radar emitter,according to the noise of the clutter modeling dynamic processing,in view of the signal uncertainty,signal delay,direct wave suppression,target detection inaccuracy problem,In this paper,a non-cooperative radar emitter target detection system based on dynamic clutter is constructed.The specific research contents are as follows:(1)Aiming at the problem of clutter Doppler frequency shift occurring in the radar configuration scenario due to the relative motion of clutter existing between the bistatic radar emitter and the receiving station and the ground object,the clutter modeling method of non-cooperative radar emitter is proposed.This method firstly established according to the cooperative movement radar radiation source and the geometry of the fixed ground station system and mathematical model,and then according to the model to describe the characteristics of doppler broadening,according to the current situation of cooperation of radiation source movement characteristics lead to build spectrum doppler characteristics,and the influence of noise distribution in the study of theory analysis and simulation.The results show that the hybrid wave property becomes more stable with the increase of propagation distance.In different configurations,the more irregular the motion state of the radiation source,the higher the clutter degree of freedom and the higher the complexity of clutter spectrum.The clutter modeling method of non-cooperative radar emitters extends the applicable range of clutter model and simplifies the calculation,which lays a foundation for dynamic clutter processing and target detection of non-cooperative radar emitters.(2)In order to reflect the clutter state caused by the motion of the early warning aircraft of the non-cooperative radar radiation source system,a dynamic processing method of clutter is proposed according to the characteristics of clutter spectrum.The clutter distribution under four different distribution conditions is analyzed by this method.Then,according to the velocity vector of the radiation source under the current condition,the clutter spectrum is calculated,and these different characteristic clutter distributions are distinguished by using the clutter spectrum data,and the analog signals received by the receiving station are added into the clutter distribution which has been distinguished.Finally,clutter signals of radiation source in different configurations can be obtained.Simulation results show that the four kinds of clutter distribution can wipe a seed according to its different scope to distinguish,the clutter distribution under different radiation sources velocity vector,and the results and get the conclusion that the spectrum itself,means that the radiation source under different conditions,the condition of clutter itself also is different,this also shows that the correctness of the dynamic clutter.(3)at present non-cooperative radar emitter object detection system of direct wave,clutter filter,such as difficult problem,constructs the dynamic clutter fitting sources by motion state of radar system simulation process,the system to verify whether the moving clutter can be involved in the radar target detection system,set up,first has carried on the dynamic target display parameters according to the clutter characteristics,Then the target signal is filtered out and the system is analyzed and tested.Simulation results show that: Join the clutter and don't add clutter signal has a significant difference between the two,by analyzing the direct wave suppression,noise filter and constant false alarm processing of signal,the system can get clear targets information,and through the adaptive beamforming,can get the target Angle information,the goal of comprehensive information error less than1%,the above results verify the validity of the model.