On the Development of Space Object Optical and LWIR Cross Section Population Distributions from UHF Cross Sections.

摘要

The resident population of artificial satellites is ever-changing, with new spacecraft and debris being orbited almost daily and older space objects decaying or commanded to earth. Decisions about deployment of future surveillance systems, in most cases requiring 5-10 years of development work before being placed in operation, must be based on a projection of the workload and target detectability which will exist in the future. This report extends to optical detection a rationale used by ADCOM to develop a future radar population. Using this radar population and empirical relationships between optical and UHF radar cross sections in the 1973 satellite population, it predicts the mean optical scattering of sunlight to be 45% of the UHF radar scattering. An analytical model is used to approximate the long-wavelength infrared (LWIR) target brightness in more-complex analogy to radar cross section. This results in a prediction that the mean LWIR cross section will be some 55% greater than the UHF radar cross section but with an uncertainty of a factor 4 in the cross section, i.e., the mean LWIR cross section should lie between 0.4X to 6.2X the UHF cross section depending on the surface materials of the spacecraft. (Author)