Complex Target Feature Database Construction And Echo Simulation System Design

With the development of high-resolution radar technology and radar target recognition technology,the target characteristic extraction methods have improved greatly.More comprehensive characteristic information can be extracted from radar echoes.Thus,the ideal echo model for point target is no longer suitable for comprehensive testing and performance verification of all functions of the radar system with high resolution and target recognition ability.While the extended target echo simulation,based on the fixed multi-scattering point model,is gradually hard to meet the increasingly stringent requirements for high fidelity echo simulation.Therefore,the echo simulation system employing real target feature information calculated by electromagnetic field numerical methods is fundamentally important for the development of high resolution radar system.The radar target characteristic modeling for complexed flying targets are researched for muti-function digital array radar in this paper.Target characteristics are calculated by electromagnetic computation software and target characteristic database is constructed,covering the whole space domain.Then,an echo simulation system for complexed dynamic targets is developed,which is based on the constructed target characteristic database.The main contents of this paper are as follows:Firstly,the target multi-scattering center model is adopted to analyze the influence of radar echo signal,involved with the target characteristic.Two important target characteristic,one dimensional range profile and angular glint,are chosen to construct the model of the target echo signal.Then,the one dimensional range profile and angular glint of the target are calculated with the help of the electromagnetic computing software FEKO and the target characteristic database is built based on the joint development platform of the application development framework QT and the database management system My SQL.Finally,a multi-channel intermediate frequency echo simulation system with 6U size modules is developed according to the VITA46.0standards.There are one high-performance signal processing circuit module and four multi-channel analog signal generating circuit modules in the system.The system software includes echo parameters calculation part installed in the digital signal processor(DSP)and the multi-channel radar echo signal generation part realized in field programmable gate array(FPGA).The designed PC based control and display APP is used to call the data from the target characteristic database and exchange inforamtion with the target echo simulation system,including the real-time visit to the database according to the dynamic target motion and the real-time parameter transmition to the system to maintain the authenticity and continuity of the generated echo signals.The designed simulation system has effectively accelated the functional testing and verification of the digital array radar,as well as the effectiveness of its target characteristic extraction and recognition functions.