Study On Dual-speed SAR Imaging And Parameter Estimation Of Moving Targets

In the field of modern radar signal processing, moving targets detection, imaging and locatingbased on synthetic aperture radar (SAR) is a hot issue. Usually, most SAR imaging algorithms aredesigned for focusing stationary targets, the image of moving targets are blurred and mis-located dueto the time-variant Doppler parameters. There are two categories of systems with the moving targetsdetection and imaging, including single channel and multi-channel system. In this thesis, a dual-speedsingle SAR system for moving targets imaging and parameter estimation is studied. In such systemthe radar platform flies with two different speeds in the radar observation time to obtain two imageswith the information of the moving targets, flowing which the moving targets can be detected, andtheir location and velocity can be estimated accurately. So the moving targets can be refocused at theirreal positions. The main work is as follows:The first chapter is a brief introduction to the history and development of SAR. Respectively, thesignificance and development of moving targets detection and imaging are studied. And the movingtargets detection and imaging classification are briefly introduced. Finally, the main research contentsof this article are pointed out.The second chapter studies the basic theory of moving target imaging in detail. First of all thelinear Range Doppler algorithm for stationary targets is introduced briefly. Based on this, the model ofmoving targets imaging is proposed, and the theory of moving targets imaging is described. Then, theecho response of moving targets is analyzed. It selectively analyses the function relationships betweenthe movement of targets and the Doppler centroid and Doppler rate, in additional, describes theimpact to the moving target imaging. Finally, several groups of simulation verify the theoreticalanalysis of this chapter.The third chapter studies moving targets imaging algorithm based on dual-speed SAR in detail.First, a dual-speed SAR moving targets imaging model is given and analyzed theoretically. Then theperformance of the moving target imaging is analyzed with some simulations based on dual-speedSAR. The moving target is focus with its real position. Finally, when considering the practicalapplication of moving target imaging based on dual-speed SAR, two situations are taken into account,focusing on the radar platform with constant acceleration. A practical method is proposed andsimulation verification. In the fourth chapter the parameter estimation of moving targets based on dual-speed SAR isstudied. First Doppler parameters of moving targets are estimated based on Radon transform andRadon-Wigner transform. Then, the value relationships of the position and velocity of the movingtarget with two Doppler parameters based on dual-speed SAR are analyzed in detail, the equations ofparameter estimation are made. Finally, some simulations are completed, and estimation of the aboveparameters is achieved efficient.The fifth chapter is the conclusion of the article. The summary of the full text of the work iscarried out and the possible direction to be further researched is pointed out.