Methods for Prediction of Atmospheric Effects on Laser Guidance Systems.

摘要

This report describes mathematical models which predict effects of atmospheric turbulence,molecular absorption and scattering,aerosol absorption and scattering,and radiative transport. Turbulence-induced angle-of-arrival fluctuations of a laser target designator are formulated to permit calculation of the fluctuation power spectrum. A numerical procedure employing the fast Fourier transform is used to convert the frequency-dependent power spectrum into the time domain giving angular beam wander. A separate computation gives the angular beamspread due to atmospheric turbulence. Descriptions of other models to determine molecular line absorption and aerosol absorption and scattering are also given. Models developed during this effort also provide first-order radiative transfer predictions and a multiple scattering model using Monte Carlo predictions. Utilization instructions are included for each of the models. (Author)