Emerging Concepts for Revolutionizing Underwater Visible Light Communication: A Review

Research on wireless information transfer in underwater environments using visible light communications (VLC) is rapidly expanding. Conventional radio frequency (RF) and Acoustic systems used in underwater settings face several limitations, such as low bandwidth and significant attenuation. To address these constraints, underwater visible light communication (UVLC) leverages the visible spectrum to provide a green, clean and safe communication solution. The key advantages of UVLC include high data transfer speeds, Minimal delay, and less power consumption, making it suitable for a variety of underwater ocean exploration tasks. This paper presents a comprehensive review of emerging technologies that enhance the performance of UVLC systems. Specifically, it explores the integration and impact of Non-Orthogonal Multiple Access (NOMA), Intelligent Reflecting Surfaces (IRS), Cognitive Radio (CR), Space-Time Block Codes (STBC), and Machine Learning (ML) within underwater communication networks. For each technology, the paper examines the roles of NOMA for spectral efficiency, IRS for link reliability, CR for dynamic spectrum access, STBC for diversity gain, and ML for system optimization and prediction. This review aims to provide future research by highlighting current advancements and integration challenges in the development of next-generation UVLC systems.