Effects of inner scale on beam wander of stochastic electromagnetic beams through atmospheric turbulence

The beam wander properties of electromagnetic Gaussian Schell-model (EGSM) beam propagating in atmospheric turbulence are investigated based on the extended Huygens–Fresnel principle, the second-order moments of the Wigner distribution function (WDF) and the Andrews beam wander theory. The simplified integral formulae for the root-mean-square (rms) beam wander and the relative beam wander of EGSM beams in turbulence have been derived. Our results indicate that in a strong turbulence, the rms beam wander increases obviously with increasing inner scale, and the influence of inner scale of turbulence on the rms beam wander can not be ignored in strong turbulence. The evolution behaviors of the rms beam wander and relative beam wander in atmospheric turbulence are quite different which depend on the initial beam width, the transverse coherence width, the inner and outer scales of turbulence. Both the rms beam wander and relative beam wander can be effectively reduced by increasing the initial beam width and decreasing the transverse coherence width.