摘要
为实现大视场成像技术指标,通过对比空间相机推扫与摆扫成像方式的视场,提出了摆扫成像方式。然后以齐次坐标变换为基础,用矩阵分析方法将其与摆镜转动矩阵结合,建立了摆扫成像像移匹配模型。在假定轨道高度为1 200km,像元尺寸为8.75μm,三片96×4 096 TDICCD拼接下的焦平面进行模拟仿真,经计算得出,在摆镜角速度为0.6(°)/s时,摆镜对飞行器的反向动量产生的角速度仅为0.000 1(°)/s,不及横滚角速度的1/10。最后通过对影响像移速度的参量进行误差分配,应用蒙特卡洛法进行误差综合,仿真结果表明:当摆镜角速度误差不大于0.000 3(°)/s时,MTF>0.95,对成像品质基本无影响。仿真结果与理论分析相符合,对工程有一定的意义。
To achieve a large field of view （FOV） imaging technology target, a whiskbroom imaging is proposed through comparing the FOV of pushbroom and whiskbroom imaging. Then, based on homogeneous coordinate transformation, this paper combines the pendulum mirror rotation matrix and homogeneous coor- dinate transformation matrix by using matrix analysis method, and establishes a whiskbroom model for image motion matching. Computer simulation is done on the assumption of the orbit height of 1 200 km, pixel size of 8.75 lam, and focal plane of three pieces of 96 x 4 096 TDICCD splicing. The results show that when the angu- lar velocity of the pendulum mirror wx= 0.6（°）/s, according to the momentum conservation principle, the an- gular velocity of the spacecraft was only 0.000 l（°）/s, less than 1/10 of the rolling angular velocity. Finally, by allocating the errors of the parameters which influence the image motion velocity, Monte Carlo method is ap- plied to analyze the residual. The results indicate that an error of pendulum mirror angular velocity △wx less than 0.000 3（°）/s has little effect on imaging quality to achieve a MTF larger than 0.95. The simulation result is consistent with the theoretical analysis, and it provides a practical guidance for engineering application.
出处
《航天返回与遥感》
北大核心
2015年第6期39-47,共9页
Spacecraft Recovery & Remote Sensing
基金
国家863高技术研究发展计划资助项目(No.863-2-5-1-13B)
关键词
大视场
摆扫成像
坐标变换
蒙特卡洛调制传递函数
空间相机
Large field of view
whiskbroom imaging
coordinate transformation
Monte Carlo
modula-tion transfer function
space camera
