New mathematical model for the intensity PDF of a laser beam propagating through turbulent media

A new doubly stochastic probability distribution function (PDF), namely the two parameter gamma-gamma distribution, is developed to describe the intensity fluctuations of a laser beam propagating through turbulent media. The lognormal distribution is the traditional governing distribution in the weak region; however in strong turbulence the intensity of a laser beam is better described by Beckman's PDF and lognormal modified PDF. It is shown in this analysis that the gamma-gamma PDFs in the strong region. The gamma-gamma PDF is compared here with recently published simulation data over a range of atmospheric conditions. Although the parameters of the gamma-gamma PDF are determined based on best fitted curves, the purpose of this analysis is to explore the existence of such a universal PDF. Unlike all other models, the gamma-gamma has a closed form CDF, making it of extreme importance for real time calculations.