Outer-scale effects on beam-wander and angle-of-arrival variances.

Single-integral equations are developed for the angle-of-arrival and beam-wander variances of propagated gaussian and uniform-intensity beams through refractive turbulence with a finite outer scale. The equations developed for Gaussian beams include initial wave-front curvature, diffraction, and turbulent spreading effects. Form-fitting expressions are used in both cases to reduce second- and third-order integral equations into equivalent single-integral forms. Numerical calculations with these new approximations give results within a few percent of the results obtained by using the more rigorous multiple integral expressions. Spectral analysis indicates that the refractive-index turbule size with the greatest influence on beam wander and angle of arrival is proportional to the outer-scale size.