Research On Algorithm Of Frequency Modulated Continuous Wave Inverse Synthetic Aperture Radar

Inverse Synthetic Aperture Radar(ISAR)has high resolution imaging capability for moving targets,which uses wideband signals to obtain high range resolution,and uses Doppler principle to obtain high azimuth resolution.Compared with optical imaging equipment,ISAR is less affected by the weather,and can detect targets all-day time.The Frequency Modulation Continuous Wave Inverse Synthetic Aperture Radar(FMCW ISAR)emits a chirped continuous wave signal with the characteristics of wide time width and low peak power,which simplifies the power amplifier at the transmitting end,it not only has the advantages of traditional radar,but also has small volume.The system has a simple structure and low cost,and has a wide range of applications in actual environment.This paper will study the FMCW ISAR system and its imaging algorithm.This paper first discusses the characteristics of the FMCW ISAR echo signal and the difference with the pulse system radar echo signal,and improves the traditional RD algorithm to adapt to the FMCW ISAR.The method of estimating the Doppler centroid in the azimuth compression of RD algorithm is investigated and discussed,and the imaging of measured data is performed.With the problem of high sidelobe of the radar imaging due to the limited bandwidth of the radar,CLEAN algorithm is introduced to improve the imaging quality of astronomical images,which has a good effect on sidelobe suppression without widening the width of the main lobe.However,because of the complexity of the actual environment,a joint sidelobe algorithm is proposed for the influence of the non-ideal of the main lobe and the sidelobe on the CLEAN algorithm,it has good effects on simulations.Finally,the principle of each part of FMCW ISAR system is introduced,and the actual monitoring experiment of moving vehicles is carried out.By using of the optimization method of this paper for data processing,the optimization of the results verifies the efficiency and effectiveness of the proposed algorithm.