Numerical solution for the fourth-order coherence function of a plane wave propagating in a two-dimensional Kolmogorovian medium

We present a numerical solution for the fourth-order coherence function of a plane wave propagating in a random medium. The random medium is taken to be two dimensional, homogeneous, and isotropic with a universal Kolmogorov (pure) power-law form. Our results differ from previous numerical calculations principally in the way in which the scintillation index approaches saturation. We display the full spatial dependence of the fourth moment and the spatial evolution of the covariance function of the intensity fluctuations. Our results are compared with previously obtained numerical results, with several asymptotic expressions, and with recent analytical methods.