A Modified CSA Based on Joint Time-Doppler Resampling for MEO SAR Stripmap Mode

作者：Liu, Wenkang; Sun, Guang-Cai^*; Xia, Xiang-Gen; Chen, Jianlai; Guo, Liang^*; Xing, Mengdao

来源：IEEE Transactions on Geoscience and Remote Sensing, 2018, 56(6): 3573-3586.

DOI：10.1109/TGRS.2018.2802545

• 2-D space variance
• azimuth resampling
• chirp scaling (CS)
• medium-earth-orbit (MEO) synthetic aperture radar (SAR)
• stripmap mode

Image formation of large scenes is still challenging in medium-earth-orbit (MEO) synthetic aperture radar (SAR) due to the existence of severe 2-D space variance. In this paper, the properties of space variance are analyzed in detail, and then a variable-coefficient fourth-order range model is adopted to model the space-variant range history of every target in a large scene accurately. A method integrating a modified chirp scaling algorithm with joint time-Doppler resampling is proposed to address the range-variant range cell migration, as well as the azimuth-variant frequency-modulation rate and higher order Doppler parameters. The computational burden and alternative implementation approaches are also discussed. Finally, processing of simulated data for MEO SAR with 2-m resolution is presented to validate the proposed algorithm.

• 出版日期2018-6
• 单位西安电子科技大学