Acquisition of High Resolution Image by Virtual Stabilization of Observation Satellite

Jitter motion of imaging-type instruments is one of the significant sources of image degradation. The stabilization mechanism is often specified by requiring that image motion be less than some value over certain time interval. In the case of observation satellites, pointing stability of the attitude control system is specified. This is an excellent starting point, but may result in the attitude control system with more capability, hence higher cost and longer development period. Therefore in this paper, a virtual pointing stabilization method is proposed. In this method, the pointing error closely related to the image spatial resolution is numerically compensated at the image processing phase in place of the mechanical stabilization. The pointing error includes both deterministic elements and stochastic ones, and both of them degrade the spatial resolution. In the proposing method, multiple images for a same target are acquired with short exposure time. Then they are composed after compensation of the deterministic pointing error. At last, effects of the stochastic pointing error are compensated by an image restoration filter. Effectiveness of the proposed method is verified through both experiments with a grand test bed and numerical simulations with a complex attitude dynamics model.