Abstract. The differential phase-shift keying-based dual-hop underwater wireless optical communication-free-space optics (UWOC-FSO) convergent system is proposed for UOWSNs and Internet of Underwater Things (IoUT) applications. In the proposed system, the collected sensor data are transmitted to a decode-and-forward relay using underwater optical wireless communication links modeled as gamma–gamma distribution. The relay transmits the signal to the terrestrial destination using free-space optical link modeled as Malaga distribution. The end-to-end performance of the system (novel expression for asymptotic bit error rate) is derived and analyzed over combined channel model (including the effects of attenuation, turbulence, and pointing errors for both FSO and UWOC channels). The in-depth study is carried out for different weather conditions of FSO (attenuation—very clear, haze, rain, and fog; turbulence—weak and strong; and pointing error—weak and strong based on the g values 1, 2, and 6) and UWOC (attenuation—clear, coastal ocean, and turbid harbor; turbulence—weak, moderate, and strong; and pointing error—weak and strong based on the g values 1, 2, and 6), respectively. The proposed system is highly useful in coastal environments, where the climate is changing adequately as clear, rain, haze, and fog.

中文翻译：

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具有指向误差的不同湍流和天气条件下会聚水下无线光通信自由空间光学系统在组合信道模型上的渐近误码率分析

摘要。基于差分相移键控的双跳水下无线光通信自由空间光学 (UWOC-FSO) 会聚系统被提出用于 UOWSNs 和水下物联网 (IoOUT) 应用。在所提出的系统中，收集的传感器数据使用建模为伽马-伽马分布的水下光无线通信链路传输到解码转发中继。中继使用建模为马拉加分布的自由空间光链路将信号传输到地面目的地。系统的端到端性能（渐近误码率的新表达式）是通过组合信道模型（包括 FSO 和 UWOC 信道的衰减、湍流和指向误差的影响）推导出和分析的。针对FSO的不同天气条件（衰减——极晴、阴霾、雨、雾；湍流——弱强；指向误差——弱强）进行了深入研究，基于g值1、2和6) 和 UWOC（衰减——清澈、沿海海洋和浑浊的港口；湍流——弱、中和强；和指向误差——分别基于 g 值 1、2 和 6 的弱和强）。提议的系统在沿海环境中非常有用，在那里气候变化很大，如晴、雨、霾和雾。分别。提议的系统在沿海环境中非常有用，在那里气候变化很大，如晴、雨、霾和雾。分别。提议的系统在沿海环境中非常有用，在那里气候变化很大，如晴、雨、霾和雾。