Visible imaging characteristics of the space target based on bidirectional reflection distribution function

A modelling method for visible imaging characteristics of a space target is presented. Background radiation of a space target consists of direct solar radiation, reflected radiation from the earth and the moon, and that from other stars. The target surface was divided into grids and the light reflection properties of each grid are described by introducing a bidirectional reflection distribution function (BRDF) model obtained in advance. Then a mathematical model for the visible imaging properties of the space target was built using given parameters of the optical detection system. Visual surfaces of the target to detection system were determined by a vector coordinate method. Simulation of the target optical imaging characteristics in orbit was achieved according to its given physical dimensions and parameters. The results show the method is feasible and robust for optical characteristics of the space target. It can provide a facility for real-time analysis of optical imaging characteristics of space targets.