Abstract:

To overcome the difficulty of accurately detecting more spatial dim and weak targets， this paper proposes a method to improve the detection sensitivity of the star sensor based on multi-frame stick of gyroscope measurement data. Before star maps are overlaid， the angular velocity measured by the gyroscope is processed， and fixed pattern noise is removed. With the bright stars in the map as the reference， the difference， the angular velocity deviation， between the moving vectors of the bright star calculated from angular velocity and that from the actual measurement are achieved. The accurate moving distance of the target in the map will be got based on the modified angular velocity. Then， the star points can be stuck precisely according to the accurate moving distance. The target energy is effectively accumulated and the background noise reduced by sticking. Simulation analysis and test verification show that the proposed method can effectively improve the target signal-to-noise ratio， improving the detection sensitivity.

Key words: dim target in space, gyroscope, angular velocity deviation, muti-frame stick, signal-to-noise ratio, sensitivity