Research on the Enhancement Method of Small Moving Targets with Low Signal-to-Noise Ratio

Small moving targets with low signal-to-noise ratio have the characteristics of weak intensity and small size. For stationary targets, it can be enhanced by the time-domain multi-frame accumulation algorithm. However, for small moving targets, the traditional direct multi-frame accumulation method cannot effectively enhance the target due to the change of the position of the target between frames and the spread of target energy. Based on this feature, this paper proposes an enhancement method based on uniform moving small targets. Because the target moves at a uniform speed between frames, the target smear image can be obtained by directly accumulating multiple frames of the collected target image sequence according to the stationary target, and then according to the smear information, the real moving speed of the target can be reversed. Finally, according to this speed, the small target image sequence is shifted and accumulated by multiple frames. In order to verify the effectiveness of the proposed method, the experiment is designed to simulate the motion of a small target by carrying a faint point light source on a motorised slide at constant speed, collecting data for correlation processing. The experimental results show that the method proposed in this paper can quickly and accurately estimate the speed of the small target moving between frames. The accumulation of small target images shifted according to this speed can significantly enhance the target and improve the signal-to-noise ratio.