Research On Waveform Design Method Of Low Sidelobe Radar

Modern radar systems use pulse compression technology to improve the ability to detect long-range targets.The pulse compression processing of traditional large time-wide bandwidth product radar signals can significantly improve the signal-to-noise ratio and radar range resolution.The pulse compression output of the traditional waveform has a high range sidelobe.Excessively high range sidelobes will lose weak targets and produce false targets.In order to reduce the distance sidelobe of pulse compression and meet the needs of small target detection in radar observation scenarios,this article introduces orthogonal frequency division multiplexing technology to optimize the design of low sidelobe radars.The main research work is as follows:1.According to the basic concept of OFDM radar,the cyclic prefix of OFDM in communication is introduced into the radar system.The OFDM radar signal model based on CP is constructed.And the basic principle of its echo signal pulse compression algorithm is given.Through simulation experiments,the effectiveness of suppressing range sidelobes is verified,laying a foundation for subsequent research.2.Combining the basic concept of m-sequence coded signal,this article performs msequence phase code modulation on CP-based OFDM radar signal,and analyzes the influence of m-sequence on CP-based OFDM radar signal range sidelobe suppression.Then based on the basic concept and principle of genetic algorithm,genetic algorithm is applied to radar signal optimization,mainly by using genetic algorithm to optimize m-sequence,so as to suppress the sidelobes of OFDM radar.Through simulation experiments,it is verified that genetic algorithm can improve the sidelobe suppression effect of m-sequence OFDM radar signal based on CP.3.This article applies swarm intelligence optimization algorithm to OFDM radar low sidelobe waveform optimization design.Based on particle swarm optimization,seagull optimization algorithm,equilibrium optimizer and slime mould algorithm,the pulse compression sidelobe of OFDM radar is suppressed.Through simulation experiments,these algorithms are effective for the low-range sidelobe design of CP-based OFDM radar.Compare the above group intelligent optimization algorithms by using evaluation criteria such as peak sidelobe level and mean sidelobe level,comprehensive analysis shows the applicability of the four algorithms in CP-based OFDM radar low-range sidelobe design.