10 Gbps optical wireless communication system using laser diodes in coastal water environment

Nowadays, underwater optical wireless communication (UOWC) has gained more attention because it provides long-distance high data-rate transmission, which has high transmission bandwidth compared to acoustic communication and radio frequency communication system. Here, we have proposed and demonstrated an UOWC architecture using 450 nm blue laser diode (LD), 520 nm green LD and 650 nm red LD as optical transmitter using on–off keying non-return-to-zero modulation scheme. A record high data rate up to 10 Gbps over 38 m distance for green LD, 34 m distance for blue LD and 28 m distance for red LD for coastal water is successfully transmitted in the proposed system. The bit error rate of the transmitted data is found to be 2.3× \({10}^{-9}\) ${10}^{-9}$ over 38 m distance for green LD, 1.31× \({10}^{-9}\) ${10}^{-9}$ over 34 m distance for blue LD and 3.01× \({10}^{-9}\) ${10}^{-9}$ over 28 m distance for red LD. A very good Q value as well as an excellent open eye diagram has been achieved. So, the proposed system is suitable for UOWC with high data-rate transmission for coastal ocean water over significantly long distance.