Two-scale solution for atmospheric scintillation from a point source

In a previous paper [ J. Opt. Soc. Am. A2, 2133 ( 1985)] we presented three-dimensional numerical solutions for the scintillation index versus the range for a plane wave propagating in the atmosphere, based on the two-scale approximate solution to the fourth-moment equation. In that paper the refraction-index fluctuations were represented by a modified Kolmogorov spectrum, which included an inner scale. In the present paper we present the equivalent results for a point source. The spectrum here is modeled by a function that is somewhat different from that used in the previous paper, and we discuss the relation between the two. The results of the present paper are of interest because they can be compared with recent experimental data.