Angular spread and directionality of cosh-Gaussian array beams propagating through atmospheric turbulence

The closed-form expressions for the mean-squared beam width and the angular spread of cosh-Gaussian (ChG) array beams propagating through atmospheric turbulence are derived by the integral transform technique. The condition in which ChG array beams have the same directionality as single Gaussian beam is given. It is shown that the angular spread of ChG array beams for coherent combination is smaller than that for incoherent combination, while the latter is less sensitive to turbulence. For coherent combination, the angular spread oscillates when the decentered parameter, waist width and relative separation distance of beams vary. And the oscillatory behavior becomes weaker in turbulence. For incoherent combination, the angular spread is independent of the relative separation distance of be