地球同步轨道二维扫描像移补偿技术建模与分析

在建立二维扫描观测模型的基础上,提出了基于椭球体地球模型的二维扫描像移补偿方案,给出了任意空间观测到的目标位置的快速迭代算法,并以真实轨道和仿真姿态数据验证了像移补偿模型的实际性能。仿真结果表明,对于长周期(大于一个东西方向扫描行周期)轨道和姿态偏差,可以通过调整仪器坐标系内的扫描轨迹来实现像移补偿;同时,在现有轨道测量和控制条件下,轨道因素引起的瞬时方位角和俯仰角补偿量在0.01°~0.1°量级,且随轨道位置不同而变化。FY-2C卫星在轨偏航轴姿态失配修正实例证实了上述模型的有效性。

Image Shift Compensation Modeling and Analysis for Two-Dimensional Scanning on Geostationary Orbit

Based on the model of two-dimensional scanning observation, the two-deimensional image shift compensation (ISC) model is proposed with an ellipsoid model for the Earth. Meanwhile, a fast iterative algorithm is also set up for the position determination of the observed objects from space. The real performances of this model are validated with some practical orbital elements and simulated attitudes. The results show that, for the long-term (namely more than one scanning period in the west-east direction) errors from orbit and attitude, ISC is realized by adjusting the scanning traces in the instrumental reference frame. The instant compensations in both azimuth and elevation are in the order of 0.01°～0.1° under the condition of the existing orbit measurement and control capabilities, and vary with the orbital positions. A real example of adjusting attitude misalignments in yaw direction of FY-2C validates the performance of the above model further.