Absorption and scattering effects of Maalox, chlorophyll and sea salt on a micro-LED based underwater wireless optical communication
In this work, a blue gallium nitride (GaN) micro-LED based underwater optical communication (UWOC) system was built, and UWOCs with varied Maalox, chlorophyll and sea salt concentrations were studied. Data transmission performance of the UWOC and the influence of light attenuation were investigated systematically. Maximum data transmission rates at the distance of 2.3 m were 933, 800, 910 and 790 Mbps for experimental conditions with no impurity, 200.48 mg/m3 Maalox, 12.07 mg/m3 chlorophyll and 5kg/m3 sea salt, respectively, much higher than previously reported systems with commercial LEDs. It was found that increasing chlorophyll, Maalox and sea salt concentrations in water resulted in an increase of light attenuation, which led to the performance degradation of the UWOC. Further analysis suggests two light attenuation mechanisms, e.g. absorption by chlorophyll and scattering by Maalox, are responsible for the decrease of maximum data rate and the increase of bit error rate. Based on the absorption and scattering models, excellent fitting to the experimental attenuation coefficient can be achieved and light attenuation by absorption and scattering at different wavelengths was also investigated. We believe this work instructive to apply UWOC for practical applications.
Tian Pengfei,Cui Xugao,Chen Honglan,Wang Peiyao,Liu Xiaoyan,Chen Xinwei,Zhou Gufan,Zhang Shuailong,Lu Jie,Qiu Pengjiang,Qian Zeyuan,周 小林,Fang Zhilai,Zheng Lirong,Liu Ran. Absorption and scattering effects of Maalox, chlorophyll and sea salt on a micro-LED based underwater wireless optical communication[J].Chinese Optics Letters,2019,17(10):10.