Research On Echo Simulation And Signal Generation Method For Complex Modulated Radar Signals

Radar simulators are used to perform target environment simulation,target echo simulation,noise simulation,that is economical,efficient,and reproducible.The complex modulation signal has the advantage of good anti-interception,In this thesis,a complex modulation radar signal echo simulation method is designed and implemented.This method can generate Phase coded Signal,FSK Signal,Double Linear frequency modulation Signal,Sine FM Signal,Polynomial FM Signal,Chirp and two-phase coding combined modulation Signal.The motion characteristics simulation and distance characteristic simulation of point target can be performed by setting the signal parameters.This thesis focuses on the algorithm theory and key technologies of the above-mentioned complex modulation signal point target echo generation,and implements the complex modulation radar signal echo simulation algorithm on FPGA(field programmable array).Main works are as follows:1.Aiming at six complex modulation signals mentioned in this thesis,which are Phase coded Signal,FSK Signal,Double Linear frequency modulation Signal,Sine FM Signal,Polynomial FM Signal,Chirp and two-phase coding combined modulation Signal.This thesis do research on the specific generation methods and implementation methods of these six kinds of intermediate frequency complex modulation signals.2.Aiming at the target motion characteristics simulation and distance characteristic simulation,the FPGA implementation method of high-speed parallel frequency shift and the implementation method of parallel delay are researched.Through the design of the echo signal-to-noise ratio,a high-efficiency power controllable Gaussian white noise efficient generation method is realized.3.Aiming at the frequency response distortion problem of DAC zero-order keeper,a distortion preprocessing method based on digital filter is studied.Based on the structure of parallel FFA filter,the high efficient implementation of 16-channel parallel filter is studied and compared the resource consumption with traditional multi-filter structure.4.The hardware structure of the complex modulation radar echo signal generation and the FPGA implementation flow are described in detail,the specific functions and resource consumption of each module in the FPGA are analyzed,and compared with the traditional methods,the function and index test were completed on the hardware platform,which verified the feasibility and efficiency of the algorithm.