Open AccessSpatially correlated gamma-gamma scintillation in atmospheric optical channels
Author(s) -
José María Garrido-Balsells,
Antonio Jurado-Navas,
José F. Paris,
Miguel Castillo-Vázquez,
Antonio Puerta-Notario
Publication year - 2014
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.021820
Subject(s) - scintillation , spatial correlation , probability density function , gamma distribution , optics , statistical physics , independent and identically distributed random variables , exponential function , monte carlo method , physics , free space optical communication , exponential distribution , turbulence , correlation function (quantum field theory) , exponential decay , random variable , optical communication , computational physics , statistics , mathematics , spectral density , mathematical analysis , meteorology , quantum mechanics , detector
In this paper, novel analytical closed-form expressions are derived for the probability density function of the sum of identically distributed correlated gamma-gamma random variables that models an optical atmospheric channel communication with receiver spatial diversity. The mathematical expressions here proposed provide a general procedure to obtain information about the scintillation effects induced by turbulence over a diversity reception scheme implementing equal-gain combining method. Both, validity and accuracy of the obtained statistical distribution are corroborated by comparing the analytical results to numerical results obtained by Monte-Carlo simulations. These simulations are particularized for constant, exponential and circular correlation models, corresponding to three different receivers spatial configurations. In addition, the extreme situations of no correlation and fully correlated received signals are also studied. The presented expressions lead to a simple and easy-to-compute analytical procedure of analyzing atmospheric optical communications systems with correlated spatial diversity.