星载双站SAR采用距离-多普勒算法的保相成像

星载双站合成孔径雷达(SAR)的成像可以采用距离-多普勒(RD)算法.算法的距离模型可使用二次模型和直线模型,针对系统双站的特点,讨论了高精度距离模型参数的求取方法.传统RD算法采用二次模型,在斜视情况下,二次模型可能会有较大误差,主要是会影响方位向压缩,因此讨论采用直线模型对应的方位压缩因子进行成像,从而改善方位向旁瓣.成像中为了使算法能够保相,需采用合适的方位向压缩因子,使其不破坏所成像的相位信息.

Phase-preserving Imaging for Spaceborne Bistatic SAR by Range-Doppler Algorithm

Range-Doppler algorithm can be applied to imaging of spaceborne bistatic SAR. Range models used by the algorithm include quadratic model and beeline model. Considering the bistatic character of the system, method of getting precise range model parameters was studied. RD algorithm was deduced using quadratic model. In squint side-looking situation, quadratic model may have inignorable error. The error mainly can influence azimuth compression. In order to suppress azimuth sidelobe, imaging using azimuth compressing function according to beeline model was studied. For preserving image phase, right azimuth compressing function should be used to avoid destruction of the phase.