Hybrid Terrestrial -Underwater Optical Communications Link
DOI:
https://doi.org/10.24237/djes.2025.18409Keywords:
Multiple FSO/FOC, EDFA-FOC, UOWC , NLOS , Atmospheric attenuationAbstract
This study presents the design and performance evaluation of a hybrid optical communication system capable of supporting high-rate data transmission across both terrestrial and underwater environments. Conventional free-space optical (FSO) and underwater optical wireless communication (UOWC) systems have typically been investigated in isolation, limiting their applicability in scenarios requiring seamless air–water connectivity. To overcome this limitation, we propose and analyze an integrated hybrid FSO–UOWC system using OptiSystem simulations. The system incorporates an Erbium-Doped Fiber Amplifier (EDFA) to compensate for atmospheric attenuation and improve the received optical signal. Simulation results demonstrate that the proposed design significantly enhances link quality, with the received signal power improving from –29.5 dBm (without EDFA) to –5.48 dBm (with EDFA). Correspondingly, the quality factor increased from 16.18 to 60.05, ensuring reliable transmission with a bit error rate (BER) maintained below 10⁻⁹. The hybrid link also supports reliable operation over water depths of up to 30 m, extending its practical applicability for marine monitoring, defense, and offshore communication networks. Compared to conventional single-medium solutions, the proposed system provides higher capacity, longer range, and improved robustness against alignment and attenuation challenges at the air–water interface. Overall, this work highlights a novel hybrid optical framework that effectively bridges terrestrial and underwater channels, offering a promising solution for next-generation broadband optical communication systems.
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Copyright (c) 2025 Satea Hikmat Alnajjar, Mohammed K. Al-obaidi, Mahmood J Ahmad, Baraa Munqith Albaker
This work is licensed under a Creative Commons Attribution 4.0 International License.
