Shen Shijian, Nie Xin, Zhang Xinggan
School of Electronic Science and Engineering, Nanjing University, Nanjing 210023, China.
Nanjing Research Institute of Electronics Technology, Nanjing 210039, China.
Sensors (Basel). 2018 Feb 3;18(2):455. doi: 10.3390/s18020455.
Gaofen-3 (GF-3) is China' first C-band multi-polarization synthetic aperture radar (SAR) satellite, which also provides the sliding spotlight mode for the first time. Sliding-spotlight mode is a novel mode to realize imaging with not only high resolution, but also wide swath. Several key technologies for sliding spotlight mode in spaceborne SAR with high resolution are investigated in this paper, mainly including the imaging parameters, the methods of velocity estimation and ambiguity elimination, and the imaging algorithms. Based on the chosen Convolution BackProjection (CBP) and PFA (Polar Format Algorithm) imaging algorithms, a fast implementation method of CBP and a modified PFA method suitable for sliding spotlight mode are proposed, and the processing flows are derived in detail. Finally, the algorithms are validated by simulations and measured data.
高分三号（GF-3）是中国首颗C波段多极化合成孔径雷达（SAR）卫星，它还首次提供了滑动聚光灯模式。滑动聚光灯模式是一种既能实现高分辨率成像又能实现宽测绘带成像的新型模式。本文研究了星载SAR滑动聚光灯模式下的几项高分辨率关键技术，主要包括成像参数、速度估计和模糊消除方法以及成像算法。基于所选用的卷积反投影（CBP）和极坐标格式算法（PFA）成像算法，提出了CBP的快速实现方法和一种适用于滑动聚光灯模式的改进PFA方法，并详细推导了处理流程。最后，通过仿真和实测数据对算法进行了验证。
