摘要
传统SAR成像技术产生的运动目标图像是散焦的,且其成像位置偏离真实位置,为了得到运动目标的真实运动及位置信息,必须对其重新定位。运动目标的定位关键在于多普勒参数的估计,分数阶Fourier变换作为一种时频分析方法已经被广泛用于运动目标的多普勒参数估计。对分数阶Fourier变换应用于运动目标多普勒参数的估计中的特点进行了详细的分析与推导,并将其与能量均衡法结合,得到了一种不需要成像即可定位运动目标的算法,并通过仿真实验验证了该算法的有效性。
If the returns from moving targets are processed in the conventional imaging way,the resulting SAR image will appear blurred and be misplaced in azimuth direction.The relocation must be carried out in order to get the real speeds and locations of moving targets.The key problem of relocation is to estimate Doppler parameters.As a time-frequency analysis method,fractional Fourier transform has been widely applied to estimating Doppler parameters.In this paper,the characteristic of using FRFT for estimating Doppler parameters has been analyzed and deduced.Combining the FRFT with the energy-equilibrium method,we proposed a method which can relocate moving targets without imaging them.The simulation results show that this method is effective.
出处
《雷达科学与技术》
2010年第4期329-334,共6页
Radar Science and Technology
