Research On Detection Technology Of Dim LEO Target In Space-based Large FOV Optical Image

With the increase of human space activities,the problem of space debris is getting worse.In order to safeguard the security of space environment,many countries are actively developing space target surveillance technology.The background of this paper is the project “research on key technology of LEO target for space-based large FOV optical surveillance”.This paper focuses on the several key technologies of space-based optical dim space target detection,which provide theoretical basis and technical support for space target surveillance.The main research content includes the following three parts:In the first part,the pretreatment algorithms of space-based large FOV image are researched.Firstly,the space radiation environment and radiation effect in space-based observation are analyzed.Then,combined with the gray feature,the distribution feature and the geometric feature of the space radiation noise,a radiation interference suppression algorithm based on multi-feature is proposed.Finally,the experimental results show that the algorithm can effectively suppress the space radiation noise.In the second part,the research on star target detection and suppression algorithm for space-based large FOV is carried out.First of all,an algorithm based on improved Hausdorff distance is proposed for inter-frame moving star target,which can match the sequence image quickly and efficiently.Based on this,a star target detection and suppression algorithm based on image sequence matching is proposed,combining centroid registration and expansion difference to complete the star target suppression.Lastly,the simulation results demonstrate that the algorithm can effectively eliminate the star target.In the third part,the dim space target detection method for space-based large FOV is researched.To start with,the motion characteristics of LEO space target in space-based large FOV observation system are analyzed.Then,based on the research of the first part and the second part,combined with the motion rule of space object,a dim space target detection algorithm based on RANSAC is proposed,which use curve model to confirm the space target.At last,the effectiveness of the proposed algorithm is verified by experiments.