Research On Simulation Of High-dynamic Star Images In Near Space

Near Space is the height of space between20and100km. As near space aircraft istaking more and more attention, its relative technology are developed rapidly. At thepresent stage, advantages provided by celestial navigation system are much more than theothers. Simulating star images captured by star sensor on the near space aircraft in pc inorder to study the performance of the navigation algorithm is necessary, which can avoidthe expensive costs and endless period. Recent studies focused on simulation of ideal starmap, but the studies of near space environment on the star maps are lacking. Therefore,this paper focused on the simulation of high dynamic star map in near space.At first, we present the research status of star maps simulation, analysis the principleand procedure. which analyzed the and deduced formulas of key problems, such aspreparation of star catalog, search of star information, coordinate transformation, energymapping to gray and point spread function of star.Secondly, we analysis the influence of near space environment on the star images andbased on the analyses we create a simulation model. We study the influence of vibration inaircraft, aberration, atmosphere refraction, aero-optical effects and the noise respectively:establish relation between power spectral density and random amplitude in quantification;analysis the influences of aberration caused by speed of aircraft, diurnal and annual courseof the Earth; established the model of atmosphere refraction changed with height; realizedvisualization simulation of aero-optical effects by superposition several random spotfunctions.