双基地角时变下的逆合成孔径雷达越分辨单元徙动校正算法

发布时间：2018-09-19 11:53

【摘要】：采用双基地逆合成孔径雷达距离-多普勒算法成像时,目标尺寸较大或累积转角过大,会引起越分辨单元徙动现象,影响成像质量.针对双基地角时变下逆合成孔径雷达成像的越分辨单元徙动问题,提出了一种校正算法.首先,建立了双基地逆合成孔径雷达回波模型,分析了越分辨单元徙动的产生机理,并通过广义的Keystone变换实现了越距离单元徙动的校正,同时消除了目标非匀速转动对成像的影响.然后,基于图像对比度最大准则估计了图像的等效旋转中心位置,并对距离向绝对定标,进而构造补偿相位项,完成了越多普勒单元徙动的校正.仿真实验结果表明,此方法能够有效地校正双基地角时变下的越分辨单元徙动,提高成像质量.
[Abstract]:When bistatic inverse synthetic Aperture Radar range-Doppler algorithm is used, the size of the target is large or the cumulative rotation angle is too large, which will cause the migration of the cross-resolution unit and affect the imaging quality. A correction algorithm is proposed to solve the problem of cross-resolution cell migration in bistatic angle time-varying inverse synthetic aperture radar (SAR) imaging. Firstly, the echo model of bistatic inverse synthetic aperture radar is established, and the mechanism of cell migration is analyzed, and the migration correction is realized by generalized Keystone transform. At the same time, the effect of the non-uniform rotation of the target on the imaging is eliminated. Then, based on the maximum contrast criterion, the equivalent rotation center position of the image is estimated, and the distance is absolutely calibrated, then the compensated phase term is constructed, and the migration correction of the cross Doppler unit is completed. The simulation results show that the proposed method can effectively correct the migration of the cross-resolution unit under bistatic angle time-varying and improve the imaging quality.
【作者单位】：军械工程学院电子与光学工程系;北京理工大学信息与电子学院;
【基金】：国家自然科学基金(批准号:61271373) 上海航天科技创新基金(批准号:SAST201240)资助的课题~~
【分类号】：TN958

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