一种补偿因子区域不变的CS成像算法

为提高星载合成孔径雷达（SAR）成像的实时性，减小补偿因子的运算量，提出了一种补偿因子区域不变的Chirp Scaling（CS）成像算法. 这种改进的CS算法根据补偿因子的相位误差确定一个更新步长，在每个步长内更新一次补偿因子，即相邻单元内的数据与相同的补偿因子相乘. 利用这种改进的CS算法对点阵目标和实测目标进行了仿真验证，得到的SAR图像质量与传统CS算法的结果相差很小. 这种补偿因子区域不变的CS成像算法在满足精度的前提下使得补偿因子的运算量成倍减小，大大减小了实时成像的压力，能够有效降低星上实时处理系统的规模，从而降低系统功耗. 

A New Chirp Scaling Algorithm Using Region-Constant Phase Multipliers

In order to enhance real-time imaging performance of spaceborne synthetic aperture radar (SAR) and reduce the computation of phase multipliers, a new Chirp Scaling (CS) algorithm was presented, which uses region-constant phase multipliers (RCPM) at some adjacent points. In the RCPM algorithm, an updating step needs to be set based on the relative errors of the phase compensation. Then signals of points within an updating step were multiplied by the same phase multiplier. Using this improved CS algorithm, the simulation verification between point objectives and measurement objectives was done, and the difference between the SAR image quality and the result of the traditional CS algorithm is small. The RCPM imaging algorithm can greatly simplify the computation of phase compensation under the premise of the accuracy and can reduce the burden of real-time imaging. It can reduce the size of real-time imaging and storage resources.