Average spreading and beam quality evolution of Gaussian array beams propagating through oceanic turbulence

Abstract

The propagation properties of a radial Gaussian beam array through oceanic turbulence are studied analytically. The analytical expressions for the average intensity and the beam quality (power-in-the-bucket (PIB) and M2-factor) of a radial beam array in a turbulent ocean are derived based on an account of statistical optics methods, the extended Huygens-Fresnel principle, and the second order moments of the Wigner distribution function. The influences of w, ε, and χT on the average intensity are investigated. The array divergence increases and the laser beam spreads as the salinity-induced dominant, ε decreased, and χT increased. Further, the analytical expression of PIB and the M2-factor in the target plane is obtained. The changes of PIB and the M2-factor with three oceanic turbulence parameters indicate that the stronger turbulence with a larger w, smaller ε, and larger χT results in the value of PIB decreasing, the value of the M2-factor increasing, and the beam quality degrading.