Infrared characteristics of on-orbit targets based on space-based optical observation

摘要

A modeling method of infrared characteristics of the on-orbit target was presented by a comprehensive consideration of the influence of structure, material, background, attitude and surface self-shadowing of the target at the larger scale. A physical and mathematical model of background radiation was established based on the blackbody radiation theory. The target surface was divided into regions based on structure and material properties and each region was divided into grids by finite element method. Bidirectional Reflection Distribution Function (BRDF) measured in advance was introduced to describe infrared reflection characteristics of each grid and a mathematical model on reflected radiation of the target was built by summing reflection of each grid. The thermal equilibrium temperature of the target surface was calculated by node network method and a mathematical model on emitted radiation of the target was built. Then a body coordinate system was set to describe the relative positions of the target, background radiation sources and detector by coordinate conversion and determine contributed surfaces of the target to the detector. Simulation of the target infrared characteristics on orbit was achieved. The results provide a feasibility of using material properties for satellite detection to within the accuracy of materials measurement and real-time simulation capabilities of computer.