Modeling And Simulation Of Spaceborne AMTI Radar System

Spaceborne air moving target indication(AMTI)radar uses satellites as a platform and has advantages over traditional radars,such as wide detection range,strong survivability,and less restraint.It has great application value in the military field and has become the focus of current radar technology research.However,spaceborne AMTI radar is difficult to implement and complex in design,so far it has not been put into practical use.Therefore,the use of computer simulation technology to model and simulate the spaceborne AMTI radar system can not only carry out the key technologies of the spaceborne AMTI radar system quickly and effectively,but also provide a powerful basis for the evaluation of the system's target detection performance.Focuses on the research of spaceborne AMTI radar,the two key parts of echo generation and space-time adaptive processing(STAP)are analyzed in this thesis.Based on this,a radar simulation system which can realize the AMTI processing process is built and verified.The requirements of the spaceborne AMTI radar simulation system is analyzed,and the design plan of the spaceborne AMTI radar simulation system is proposed in this thesis.Firstly,the simulation system is divided into antenna module,echo generation module,equivalent yaw compensation module,STAP processing module,constant false alarm rate(CFAR)detection module and target speed estimation module.Secondly,the geometric relationship between the spaceborne radar and the earth is analyzed,the relationship between various parameters is deduced and simulated,and the range aliasing phenomenon and Doppler effect of the spaceborne radar are discussed and analyzed.Then the echo model of spaceborne radar is established to simulate the two-dimensional space-time echo signal;the influence of earth rotation,range ambiguity and Doppler ambiguity on spaceborne radar clutter is analyzed,and the correctness of the echo model is verified by simulating the power spectrum,angle Doppler trace and range Doppler spectrum of spaceborne clutter in different scenes;at the same time,starting from the optimal STAP,the effects of Doppler ambiguity,range ambiguity and earth rotation on the clutter suppression performance are simulated and compared.;aiming at the shortcomings of full-dimensional STAP in practical applications,two dimensionality reduction STAP algorithms of multi-channel joint adaptive processing(m DT)and joint local processing(JDL)are analyzed and their performance is compared by simulation.Aiming at the problem that the earth's rotation causes the clutter to produce distance non-stationary and the target detection performance decreases,the Doppler compensation method is adopted to reduce the influence of the earth's rotation.The effectiveness of this method is verified by simulation.Finally,the Simulink platform is used to build a spaceborne AMTI radar simulation system.Through the simulation test,it can be found that the system can complete the spaceborne AMTI processing flow,and has the functions of echo generation,clutter suppression,moving target detection and Target velocity estimation.The modular idea is used to model the spaceborne AMTI radar simulation system,and Simulink is used to build the simulation system in this thesis.The realized simulation system has the characteristics of low coupling,and different STAP algorithms can be used to process the echo data to achieve moving target detection and target speed estimation,which has a certain value for the simulation research and engineering application of spaceborne AMTI radar.