Performance investigation of UWOC system with multiuser diversity scheduling schemes in oceanic turbulence channels

Abstract

A multiuser diversity underwater wireless optical communication (MD-UWOC) system with four scheduling schemes was proposed and investigated over the aggregated log-normal fading channels. Specifically, for the Max SNR and selective multiuser diversity (SMUD), the analytical expressions of the throughput and average bit error rate (ABER) were derived with the help of Gauss quadrature rules and scaled complementary error function, which are also confirmed by Monte Carlo simulation. Results revealed that a higher throughput can be obtained for MD-UWOC system with increasing user numbers over oceanic turbulence, and this enhancement is more pronounced with increasing the rate of dissipation of mean squared temperature χT and the temperature–salinity balance parameterwfor Max SNR, SMUD and proportional fair scheduling (PFS) and modified PFS (MPFS) schemes. Besides, under weak turbulent ocean environment in the presence of absorption and scattering, the throughput performance deterioration due to the increasing link distances is more evident in coastal than that in clear ocean water for these four scheduling schemes. Furthermore, the study demonstrated the MPFS has worse throughput and ABER performances as compared to the other schemes while it provides a lower complexity approach to achieve a tradeoff between throughput and fairness compared with the conventional PFS.