中文摘要：

高轨合成孔径雷达星地构型几何复杂，低轨合成孔径雷达系统设计中距离方位不耦合的假设不再成立，常规的带宽和合成孔径时间设计方法在高轨中不再适用．针对上述问题，提出了一种适用于高轨的系统带宽与合成孔径时间优化设计方法．首先根据高轨合成孔径雷达斜距平面与地距平面的几何映射关系，得到了解析的地表分辨率表示方法；然后针对实际应用对合成孔径雷达地表分辨率大小和形状（尽量接近圆）的要求，提出了一种信号带宽与合成孔径时间优化设计方法；最后以高轨椭圆轨道为例，给出了设计实例，分辨率分析结果与后向投影法成像结果吻合，同时给出了相应的带宽与合成孔径时间设计结果．仿真结果验证了文中方法在高轨合成孔径雷达系统设计中的有效性．

英文摘要：

The complex relative motions between the Radar platform and the targets are more complex in geosynchronous Synthetic aperture radar （GEO SAR）. The assumption that range and azimuth are uncoupled in Low-Earth-Orbit SAR does not hold in GEO SAR. The common calculation method for bandwidth and synthetic aperture time cannot be used in GEO SAR. In this paper, a method suit able for GEO SAR is proposed to design imaging parameters including the bandwidth and synthetic aperture time. First, a resolution analysis method with analytical expression is deduced based on geometrical mapping, and then based this expression, the bandwidth and the synthetic aperture time are optimized to meet the resolution＇s needs on value and shape （close to a circle）. Finally, a design example in a GEO ellipse orbit is given, and the resolution analysis result corresponds to the image obtained by the Back Projection （BP） method. The designed bandwidth and synthetic aperture time are also provided. Simulation results validate the effectiveness of the proposed method in the GEO SAR system design.