Effect of Atmospheric Turbulence on the Performance of Underwater Wireless SAC-OCDMA System

Absorption, scattering and atmospheric turbulence are three main degradation factors that significantly affects the performance of any underwater optical communication system. The effect of atmospheric turbulence on the bit error rate (BER) performance of an underwater wireless spectral-amplitude-coding optical code division multiple access (SAC-OCDMA) system using Modified Quadratic Congruence (MQC) code sequence is investigated, in this paper. To define the optical atmospheric turbulence, Gamma-Gamma model is employed. In this case, a general channel model is considered to attain more accurate result where the effect of absorption and scattering is also taken into consideration. The Rytov Variance can be considered as the measure of turbulence strength. Our investigation illustrates how the system's BER performance is affected if turbulence strength is varied.