Performance Analysis of MIMO-QAM System with Pointing Errors in Underwater Málaga Turbulence Channel

The ocean turbulence and the pointing error caused by the jitter of transmitters and receivers will degrade the performance of underwater wireless optical communication (UWOC) links. To effectively alleviate the influence of ocean turbulence and pointing error, the general turbulence model, i.e., Málaga model, is adopted to characterize weak, medium, and strong ocean turbulence, and the maximal-ratio combining (MRC) diversity is employed in the MIMO receiver of the UWOC system with pointing error in this paper. Using Meijer's G-function and Laplace transform of moment generating function (MGF), the approximate expressions of the system average BER and the outage probability are derived theoretically. The impacts of the number of transceiver antennas, the receiver aperture, the QAM modulation order, the ocean turbulence strength, and the pointing error on the average BER and outage probability are numerically analyzed to verify its effectiveness in alleviating ocean turbulence and pointing error.