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Image quality degradation analysis induced by satellite platform harmonic vibration

The paper discusses how different frequencies vibrations influence the image quality and limit resolution. The main module of image quality degradation is based on the physical optical imaging process. This model builds up the accurate relationship between image space and object space, and reproduces entire imaging process from time-space joint relation. In this experiment, fixed amplitude harmonic vibrations with frequencies between 1Hz to 2000Hz applied to the 2-Dimesion unit impulse function image and standard knife edge image. Then those degenerated images are analyzed to measure the PSF (Point Spread Function) and MTF (Modulation Transfer Function). As the result, with the increase of the ratio of Te T0 , the PSF and MTF become constringent. When the ratio of Te to T0 is greater than 10, the maximum of relative error of the PSFs is less than 5%. This experiment reveals that the very high frequency vibrations have almost the same effects to degenerate the image as the relative lower frequency vibrations, which means that the frequency is not as important as the vibration amplitude.