圆轨迹环视SAR成像处理

圆轨迹环视合成孔径雷达（synthetic aperture radar, SAR）是一种能够实现广域观测的新模式合成孔径雷达，由于它特殊的运动轨迹，直线SAR的成像算法不能直接应用于圆轨迹环视SAR数据处理。然而，对于圆轨迹环视SAR系统而言，其响应函数具有“沿角度维平移不变”的特性。因此可以利用这一特性，借鉴条带SAR成像算法的思想，在频域研究圆轨迹环视SAR数据的成像方法。推导了圆轨迹环视SAR回波信号的精确二维频谱表达式，并在距离多普勒域给出了一种圆轨迹环视SAR成像方法。仿真实验验证了算法的有效性。

Imaging processing of circular trace scanning SAR

Circular trace scanning synthetic aperture radar (CTS-SAR) is a new operation mode radar, which can be used for wide observation. Because of the special track of the circular trace scanning SAR, the imaging algorithms of SAR in linear track cannot be used in processing the circular trace scanning SAR data directly. However, the response functions of the circular trace scanning SAR system can remain the consistency by changing the same aspect angle both of the target and the starting position of the radar. Because of this characteristic, the circular SAR can be processed in the azimuth frequency domain by using the imaging algorithm of SAR in linear track for reference. The exact signal spectrum expressions of circular trace scanning SAR are derived. An imaging algorithm in range-Doppler domain is presented. The simulations show the good performance of the proposed algorithm.