针对于缺少基于天基光学观测的空间目标姿态估计的问题，提出将无味卡尔曼滤波应用于基于天基光学观测的地球同步轨道目标姿态估计中.以光学横截面积代替星等作为观测量，提高观测方程的线性化水平，实现观测方程的简化；同时建立基于改进Phong模型的光学横截面积观测模型，在提高观测方程描述能力的同时，以角度作为模型的输入，极大地简化了计算，增强了实时性.最后，以贴敷聚酰亚胺薄膜及朗伯体材质的长方体为例，对比分析了姿态估计情况，验证了所提方法的有效性；并进一步对正六棱柱、正八棱柱进行了姿态估计.

In view of the lack of space objects' attitude estimation based on space-based optical observation, this paper applied the Unscented Kalman Filter (UKF) to the Geosynchronous Orbit objects' attitude estimation based on space-based optical observation. Taken the Optical Cross Section (OCS) instead of magnitude as observed variable, linearizing and simplifying the observation equation. In addition, an OCS observation model based on the improved Phong model was established, which improves the description ability of the observation equation. And the angle was used as the input of the model, which greatly simplifies the calculation and enhances the real-time capability. Finally, compare the attitude estimation of the Kapton cuboid and the Lambert cuboid, the effectiveness of this method is verified, and the attitude estimation of the regular hexagonal prism and eight prism is also carried.