The performance of underwater visible light communication (UVLC) system is severely affected by absorption, scattering and turbulence. In this article, we study the performance of spectral efficient DC-biased optical orthogonal frequency division multiplexing (DCO-OFDM) in combination with the transceiver spatial diversity in turbulence channel. Based on the approximation of the weighted sum of lognormal random variables (RVs), we derived a theoretical exact bit error rate (BER) for DCO-OFDM systems with spatial diversity. The simulation results are compared with the analytical prediction, confirming the validity of the analysis. It is shown that spatial diversity can effectively reduce the turbulence-induced channel fading. The obtained results can be useful for designing, predicting, and evaluating the DCO-OFDM UVLC system in a weak oceanic turbulence condition.

中文翻译：

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空间分集DCO-OFDM在弱湍流水下可见光通信信道中的性能

水下可见光通信（UVLC）系统的性能受到吸收、散射和湍流的严重影响。在本文中，我们研究了频谱高效直流偏置光正交频分复用 (DCO-OFDM) 与湍流信道中收发器空间分集的性能。基于对数正态随机变量 (RV) 加权和的近似值，我们推导出了具有空间分集的 DCO-OFDM 系统的理论准确误码率 (BER)。将仿真结果与分析预测进行比较，证实了分析的有效性。结果表明，空间分集可以有效地减少湍流引起的信道衰落。获得的结果可用于设计、预测、