APERTURE-AVERAGING FACTOR FOR OPTICAL SCINTILLATIONS OF PLANE AND SPHERICAL WAVES IN THE ATMOSPHERE

Previous analyses of aperture averaging of optical scintillations in the turbulent atmosphere have generally involved either numerical integrations or approximation formulas based on asymptotic results for large apertures. Here I develop the exact expressions for the aperture-averaging factor in the weak-turbulence regime for both plane and spherical waves. For computational ease, accurate approximation or interpolation formulas that can be applied in most cases of interest with greater accuracy than previous approximations are also developed.