Space-Based Detection Of Space Debris By Photometric And Polarimetric Characteristics

With the annual increase in human space activities,space debris has also increased year by year.The existence of space debris has seriously affected the safety of space activities.In order to ensure the safe operation of the spacecraft,space debris needs to be detected and tracked.Then orbit determination,identification cataloging,investigation and analysis are performed.On this basis,orbit maneuvering is implemented to ensure that the spacecraft cannot be collided.In addition,in order to ensure space safety,existing space debris will also be removed by means of off-track,recovery,and burning.Therefore,the detection of space debris is particularly important.In the past,ground-based radars had limited observation scope,and there were many inconveniences in terms of geography and politics of the external peripheral stations.Ground-based telescopes had atmospheric interference and could not observe all-weather and all-day.In this paper,space-based detection technology is used to study the space-based space debris detection method based on photometric and polarimetric information.The main work of the dissertation is as follows:Firstly,research on small-scale space debris detection technology was conducted,and a space-based space debris detection scheme based on photometric and polarization information was proposed.When the observation platform is far from the space debris(about 100km),a 10 cm space debris is similar to a point target,and the photometric detection can be performed.When the phase angle changes from 0° to 90°,the equivalent visual magnitude of space debris is between 6.9 and 8.2;when the observation distance is less than 20 km,the point target gradually exhibits the characteristics of the body target.Through the imaging observation of the polarization detection channel,the surface roughness,texture,contour and other geometric and physical characteristics of the debris can be further obtained.Secondly,for the photometric detection of space debris with a size of about 10 cm(detection distance of about 100 km)and polarization imaging of space debris with a size of 30 cm(detection distance of about 20 km),the optical specifications are demonstrated respectively.The structure selection and optimization design of the co-calibrating dual-channel optical system were carried out.The imaging quality evaluation and tolerance analysis were performed to verify the feasibility of the scheme.Thirdly,polarization spectral imaging experiments were performed on six typical spacecraft surface materials and one satellite solar panel model(electroplated navy blue paint).The typical target polarization characteristics data was obtained,which can provide support for the identification of space debris materials.Compared with the intensity image,the polarization image can enhance the details of the image and texture performance,and the angle of polarization image performed better.The degree of polarization of the yellow polyester film is generally higher than other materials in various bands,especially at 850.8nm.It is much higher than the degree of polarization of other materials at the same wavelength.Using this feature,the yellow polyester film can be distinguished from the other six materials.