Study On Environmental Modeling And Electromagnetic Scattering Characteristic Of Space Debris

With burgeoning activities of space exploration, space debris is used to be a threat to spacecraft, and its increasing will take over more and more orbits around the earth. Research on electromagnetic scattering characteristic of space debris is very important to formulate mitigating measures which is helpful to use orbits effectively. According to environmental model of space debris and scale transformation theory of ellipsoidal target, this dissertation discusses the electromagnetic scattering characteristic of space dangerous debris and dusty particles, and the main works are as following:Firstly, this dissertation introduces space debris prediction model and space density function. The long-run and short-run prediction model, as well as average space density derived and obtained. The numerical result shows that space debris will increase if activities of space exploration are more than before, and a crest value of space density occurs over the earth's polar region. Secondly, the electromagnetic scattering analytic solution of ellipsoidal target has been deduced by the scale transformation theory, in the process of which we calculates electromagnetic scattering characteristic of ellipsoidal target that contains perfect conductor and dielectric. Thirdly, the charging model of space dust and the scattering characteristic of electronic shielding cloud are obtained; The permittivity and conductivity of dusty plasma are deduced in detail which contains particle collisions and dusty charging. In the background of dusty plasma, scattering characteristic of space dangerous debris is dealt with scale transformation theory. Finally, we discuss electron density of background ionosphere and ionosphere irregularities, in which the quasi-parabolic model is used. It is significant to do research on characteristic of radio wave propagation in background ionosphere, and in which scattering characteristic of one debris and multi-debris is also discussed. When the ionosphere irregularities occurs in the ionosphere, we analyses the scattering characteristic of space dangerous debris. Characteristics of electromagnetic scattering from multi-debris are also examined according to single-scattering theory and space density of space debris.