太阳同步椭圆轨道偏流角分布规律与像质分析

提出一种根据轨道根数与TDICCD 成像原理模拟遥感器推扫成像过程，实现偏流角计算，并基于最终仿真图像的PSF 分布评价图像质量的方法，以截止频率MTF 为评价标准，研究太阳同步椭圆轨道的偏流角分布规律。结果表明:与常规圆轨道相比，近地点幅角为0的椭圆轨道在近地点一侧偏流角与轨道半长轴成线性关系，与轨道离心率成三次函数关系。使用KH-12 卫星采用的椭圆轨道参数进行成像仿真，以穿航MTF 下降5%为约束对成像质量进行分析，结果表明:相同推扫级次下，椭圆轨道近地点一侧的偏流角更小，成像质量更高。

Drift angle distribution and image quality decreasing of solar synchronizing elliptic orbit

Drift angle distribution of elliptic solar synchronic orbit was discussed with an image simulating method based on orbit elements and TDICCD imaging mechanism. Image quality was evaluated based on PSF distribution of the simulated final image, and drift angle calculation was carried out. Results show that drift angle of elliptic orbit is linear to half -major -axis and cubic polynomial to orbit eccentricity when argument of perigee is 0. Image quality distribution aimed at KH-12 camera's critical inclination orbit due to angle drifting in case MTF 0.95 was discussed. Results show that smaller drift angle at neighborhood of the perigee of elliptic orbit and higher image quality can be achieved under same integral number.