Beam Wander Effects on Scintillation Theory of Gaussian Beam through Anisotropic Non-Kolmogorov Atmospheric Turbulence for Optical Wireless Communication

Beam wander effects have been discussed as the main reason for the failure of the first-order Rytov approximation to properly predict the scintillation index of Gaussian beam through the atmospheric turbulent channel of optical wireless communication. This paper investigates the beam wander effects on scintillation theory of Gaussian beam based on the new generalized anisotropic non-Kolmogorov power spectrum, where all the influence of the anisotropy of turbulence, the general spectral power law, and the finite turbulence inner and outer scales are considered simultaneously. For both horizontal path and uplink path, novel expressions of the beam wander, the wander-induced pointing error variance and the beam-wander-induced scintillation index are derived. Numerical simulations are performed to show the significant influence of beam wander on the scintillation index in the propagation of Gaussian beam.