基于四元数的姿态变换关系在SAR运动补偿中的应用

SAR运动补偿技术是SAR系统获得高质量图像的关键。当雷达载体发生横滚角、俯仰角和偏航角运动时，天线平台需要得到实时的姿态角以稳定天线的指向，而捷联惯导系统能满足这一要求。捷联矩阵的实时修正是捷联系统姿态解算的主要任务，考虑到系统实时性和稳定性的要求，用一种新的方法推导了四元数与姿态角的变换关系，并根据此关系分析了载机角运动误差对SAR成像的影响。基于四元数的方法能减少SAR运动补偿中复杂的三角函数运算，提高了运算效率，增强了系统的实时性。

The Application of Transformation Relationship between Quaternion and Attitudes to SAR Motion Compensation

Since factors such as turbulence and pilot error make it impossible for an aircraft to flight along the nominal straight flight path, SAR motion compensation technology is crucial to acquiring high quality image. When the aircraft changes in the roll, pitch or heading, it is necessary to track the real time attitudes to stabilize the antenna pointing. While the strapdown inertial navigation system can fulfill the requirement. The instant attitude updating is one of the main tasks of attitude measurement for strapdown system. Consideration of the real time ability and stable performance, a new derivation method of the transformation equations between quaternion and attitudes is proposed. The influence of angle motion in airplane on SAR imaging is analyzed based on the derived equations. The method given in the paper can highly reduce the operation of triangle function and improve the efficiency of the system.