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摘要: 星载合成孔径雷达(SAR)通过采用不同成像模式,实现分辨率与成像带宽度的不同性能组合。常规星载SAR模式的成像带沿着卫星航迹方向,走向单一;但实际目标场景的地理走向多种多样,与沿卫星航迹方向的成像带地理走向不匹配的情况普遍出现,导致数采周期长或方位分辨低、存储与计算资源浪费。星载SAR非沿迹成像模式是解决该问题的新思路,其通过生成与卫星航迹不同向的直线型或曲线型的成像带,匹配于目标场景的实际地理走向,对目标场景进行“地理定制化”成像。该文主要从信息获取、成像处理等方面,讨论了星载SAR非沿迹成像新模式的主要机遇与挑战,并通过计算机仿真实现了星载SAR非沿迹成像模式的原理性验证。Abstract: Spaceborne Synthetic Aperture Radar (SAR) can achieve various performance combinations of resolution and observation bandwidth by adjusting the working modes. The imaging swath of the traditional spaceborne SAR working mode is along the satellite orbit, and the geographical trend is single; however, the geographical shape and direction of the surface scene are diverse and generally do not match the imaging swath along the orbit, resulting in a long data acquisition period, low azimuth resolution, and storage waste of computing resources. To this end, the spaceborne SAR Non-along-track imaging mode is a new method for spaceborne SAR scene matching that is characterized by an imaging zone that is no longer mechanically along the satellite orbit but is generated according to the actual geographical direction of the scene to achieve “customization” that matches the scene imaging. In this paper, the main opportunities and challenges faced by the new mode of spaceborne SAR scene matching are discussed from the aspects of information acquisition and imaging processing, and the principled verification of the spaceborne SAR Non-along-track imaging mode is provided through a computer simulation.
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Key words:
- Spaceborne SAR /
- Non-along-track imaging mode /
- Data acquisition /
- Imaging processing
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表 1 主要仿真参数
Table 1. Key simulation parameters
参数 数值 载频 10 GHz 脉冲宽度 20 μs 轨道高度 550 km 距离向波束宽度 0.6° 方位向波束宽度 0.6° 带宽 88.5 MHz 方位点数 147765 距离点数 163664 -
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