宽测绘带合成孔径雷达(SAR)采用了不同的信号录取方式及成像算法,但现有的ScanSAR和循序扫描体制(TOPSAR)往往会造成场景分辨率的整体下降。针对这一问题,该文采用一种新的侧摆模式进行宽幅场景成像。该模式通过距离向波束角度的变化,以损失部分积累时间为代价,得到宽幅场景的回波信号,继而采用稀疏算法在方位向实现降采样成像。仿真结果表明,在波束变化轨迹确定后,星载雷达侧摆模式下稀疏SAR成像可有效增加场景幅宽,同时确保场景中心区域的高分辨成像。
Different signal acquisitions and imaging algorithms have been presented for the wide swath imaging. However, most of these methods used in ScanSAR and Terrain Observation by Progressive scans SAR (TOPSAR) decrease the azimuth resolution for the whole scene. To mitigate this issue, a new lateral swing mode for wide swath imaging is proposed. With the angle of the beam changing, the sparse representation is used to deal with the high bandwidth caused by the wide swath coverage, being the tradeoff against the azimuth resolution, and then the proposed algorithm can produce the unambiguous imaging for the wideswath scene. The simulation results validate the presented approach, which preserves the high resolution in the center of the scene for the wide swath imaging.