基于频域分析的ROSAR成像算法

在现有的ROSAR(Synthetic Aperture Radar with Rotating antennas)成像算法中,基于斜距泰勒级数展开的算法存在方位向失配问题,时域相关卷积算法不能快速校正距离弯曲.频域ROSAR成像算法采用驻相点原理,直接对ROSAR回波信号进行二维频域变换,保留回波信号的频谱特征,进而构造相应的频域去耦函数和频域匹配函数,实现频域距离弯曲校正和目标场景重构.仿真结果表明,该算法能够快速校正距离弯曲及有效克服方位向失配问题.

ROSAR imaging algorithm based on frequency analysis

In the existing imaging algorithms for synthetic aperture radar with rotating antennas(ROSAR),the methods based on the Taylor series expansion of the slant range suffer from mismatch problems in azimuth.In addition,the time-domain convolution method cannot rapidly correct the curvature.In the proposed ROSAR imaging algorithm in frequency domain,the echo was transformed into the two-dimension frequency domain directly using the stationary phase principle.In this case,spectral characteristics of the echo signal were retained completely.Thus,the correspondent decoupling function and matching function in frequency domain were constructed to achieve the range curvature correction and scene reconstruction.Simulation results demonstrate that the proposed algorithm can perform the curvature correction rapidly.Furthermore,the proposed algorithm can overcome the mismatch problems in azimuth effectively.