High speed UOWC system using DP states with FRS-OCDMA code

This paper introduces a high transmission and secure Underwater Optical Wireless Communication (UOWC) system using Dual Polarization (DP) states, each of them carries three channels assigned with Optical Code Division Multiple Access (OCDMA) code; named, Fixed Right Shift (FRS). A comparison between different transmission powers is performed. The system performance is evaluated across five distinct water types; pure seawater (PS), clear ocean (CL), coastal ocean (CS), harbor I (HI), and harbor II (HII). Assessments encompass received power, Bit Error Rate (BER), eye diagrams, and Q-factor. Comparative analyses are conducted at data rates of 2.5, 5, and 10 Gbps across each water type. The results indicate that the Laser Diode (LD) sources with 15 dBm transmitted power yield higher received powers compared to that with 10 dBm. Additionally, the optimal system performance characterized by lower BER, higher Q-factor, and wider eye openings, is observed in water types with lower attenuation, such as PS and CL, and at lower data rates. Conversely, higher attenuation water types, like HI and HII, achieve lower performance metrics. Moreover, our model can successfully allow six channels, each delivering 10 Gbps data, propagate distances up to 35 m for PS, 22 m for CL, 13.6 m for CS, 7.1 m for HI, and 4.45 m for HII, demonstrating BER \(\sim {10}^{-4}\) $\sim {10}^{-4}$ and Q-factor of \(\sim\) $\sim$ 4.