Scintillation index and outage probability of vortex Gaussian beams for horizontal links in weak atmospheric turbulence

Abstract By using Rytov method, for the Gaussian vortex beam, off-axis scintillation index of is examined in horizontal laser communication links operating in weakly turbulent atmosphere. Performances of laser communication systems, defined by the outage probability in this study, is evaluated by the use of lognormal distributed intensity in finding the scintillation index. Off-axis scintillation index of vortex Gaussian beams is analytically derived and evaluated in horizontal atmospheric link. The scintillation index obtained from the figures drawn versus the source size and propagation length is used to calculate the outage probability. It is found that turbulence affects vortex Gaussian beam less when compared with Gaussian beams that are non-vortex. Our important finding is that the scintillation index reduces when the topological charge increases.