研究了不同成像方式下的卫星颤振光学成像退化机理,建立一套完整的卫星颤振光学成像退化模型。模型包含成像模式和颤振两大模块,以面阵凝视和TDI扫描两种成像方式建立退化模型。分析卫星颤振来源,将颤振分为线性运动、正弦颤振、随机运动以及组合颤振四种运动形式。对具有典型意义的地球静止轨道上的卫星进行仿真成像和分析,得到卫星颤振参数临界值。为验证仿真分析的结果,建立了一套模拟遥感成像的地面半物理仿真实验系统。通过对系统加载颤振激励,可得到模拟卫星颤振退化图像。利用调制传递函数(MTF)作为像质评价指标,发现理论模型计算值与实验实际获取结果具有很好的吻合性,从而证明了颤振成像退化仿真的正确性和有效性。
The mechanism of optical degradation for remote sensing imaging is analyzed under vibration, and the corresponding simulation model is built, which includes imaging module and vibrating module. The imaging module discusses how the plane-array camera and TDI camera work and the imaging module divides the vibration into four categories, including linear one, sinusoidal one, random one, and combined all of above. For the geosynchronous earth orbit satellite, the critical value of vibration is calculated by using the simulation model mentioned above. To verify the reliability of the proposed theoretical analysis, a properly designed semi-physical simulation system has been built. Loading a certain vibration parameter as the vibration source, the system can get a simulated degraded image. Using Modulation Transfer Function (MTF) to measure image quality, the images calculated from the simulation model and obtained by the semi-physical system present a good agreement, which verifies the accuracy and practical applicability of the proposed theoretical analysis.