這項工作研究了以雷射二極體為光源，用於水下無線光通訊 (UOWC) 的藍光雷射 450nm 系統。實驗室裡長1.5m和3m裝滿水的水箱模擬加入各種要素的自來水。我們分別使用155Mbps、622Mbps、1.25Gbps的數據速率，經過准直透鏡聚焦後的藍光雷射打入水箱。為了增加光線的傳輸距離，鏡子放置在水箱外面。對誤碼率 (BER) 和接收光功率的測量進行了評估，以評估和分析 UOWC 系統性能。第一種情況，UOWC 系統使用不同密度的水進行測量，其中 1.01、1.02 和 1.03 海水密度由比重計測量。此系統能在密度 1.03的水中達到 3.0 m。水流作為外部參數進行模擬水箱中不同的水密度。在我們提出的系統中，密度1.03的水流可以在 1.5 m的距離內實現 4.907 x 10-4 的 BER。而在更高的溫度下，BER 可以達到 2.18x10-6。由於傳輸信號質量受水中密度的影響，較高的密度將導致更差的 BER，並且需要更多的光功率來傳輸。我們分別在 15°C、20°C、26°C、35°C 和 40°C 進行溫度實驗，以模擬較低溫度、室溫和較高溫度。BER在最低溫度下能達到1.966 x 10-5。然而，由於較高的溫度會影響較低的密度，因此在 40°C 時信號質量更好並達2.187 x 10-6。第二種情況，UOWC 系統測量了幾種類型的水，研究了自來水、氯水、葉綠素和海水的水質。對於這些沒有雜質的實驗條件，我們使用相同的數據速率分別放入108 克氯、7 毫升葉綠素和 2.4 千克海鹽。人們發現，增加水中海鹽、氯和葉綠素的質量會通過增加光衰減來降低 UOWC 的性能。人們發現，氯衰減、葉綠素吸收和海水粒子散射的影響是導致最大數據速率降低和誤碼率增加的原因。

This work investigated a blue laser 450nm system for underwater wireless optical communication (UOWC) based on diodes was developed. The 1.5 m and 3 m lengths of the water tank filled with water conduct in the laboratory simulate the open various water. We used 155Mbps, 622Mbps, 1.25Gbps data rate, blue laser light that has been collimated with a collimated lens is injected into the water tank. In order to increase the transmission distance of the light, a mirror was placed outside the water tank. The measurement of bit error rate (BER) and receive optical power were assessed to evaluate and to analyze the UOWC system performance. First scenario, the UOWC system is measured with several types of water densities, which 1.01, 1.02, and 1.03 sea water densities that measured by hydrometers. This system is capable to achieve 3.0 meters in 1.03 dense water. Water flow was conducted as external parameters to simulate different water densities in the water tank. In our proposed system, water flow in the 1.03 water density can achieve BER of 4.907 x 10-4 over a 1.5-meter distance. At higher temperatures, the BER can reach 2.18x10-6. Since the transmission signal quality is affected by the water densities, higher water densities will result in much worse BER and require more optical power to transmit. We conducted temperature experiments at 15°C, 20°C, 26°C, 35°C, and 40°C to simulate lower temperatures, room temperatures, and higher temperatures. The BER can achieve until 1.966 x 10-5 in the lowest temperature that we use. However, the signal quality in the 40°C has better and achieve until 2.187 x 10-6 due to a higher temperature can affect a lower density. Second scenario, the UOWC system is measured with several types of water qualities, which tap water, chlorine water, chlorophyll, and sea water qualities were studied. We used same data rates, for these experimental conditions with no impurity, 108 g Chlorine, 7 ml chlorophyll, and 2.4 kg sea salt. It was discovered that increasing the qualities of sea salt, chlorine, and chlorophyll in water decreased the performance of the UOWC by increasing light attenuation. It was discovered that the effects of chlorine attenuation, chlorophyll absorption, and scattering by sea water particles are what cause the maximum data rates to decrease and increase in bit error rate.

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