Effect of spatial diversity on underwater optical wireless communication

Underwater optical wireless communication systems have recently increased in use due to their high data rate transmission feature. However, turbulence is the compelling factor in the propagation of optical waves in underwater environments. Intensity fluctuations and performance degradation due to turbulence are observed. In this thesis, a spatial diversity model designed to reduce the effects of ocean turbulence is used and performance improvements are investigated. In our designed model, a point detector is used on the receiver side and annular array beam is used on the transmitter side. The average received intensity and the mean square of the intensity are found by using the Huygens-Fresnel principle. Later, the scintillation index and bit error rate are found for the model created with the found parameters. The scintillation index and bit error rate (BER) were compared and evaluated according to the values of the rate of dissipation of kinetic energy per unit mass of fluid, ratio of temperature to salinity contributions to the refractive index spectrum, source size, ring radius, field amplitude, the rate of dissipation of the mean-squared temperature, Kolmogorov inner scale, propagation distance and wavelength. Calculations were made using the MATLAB program and graphics were created. In this thesis, it is aimed to observe the decreases in scintillation and BER calculation for beam propagation in underwater turbulent environment.