Exploring the Effect of a Wavy Sea Surface on NLOS-UOWC Systems: A Novel Deterministic Approach

Abstract

This work presents a novel approach to modeling an underwater optical wireless communications (UOWC) channel based on a deterministic analysis specifically for non-line-of-sight (NLOS) configurations. The model considers the presence of a wavy ocean surface, providing a more accurate representation of realistic conditions. By expanding the possibilities for communication in complex underwater environments, our model offers a comprehensive analysis of the ocean waves’ impact. A significant achievement of this study is the capacity of the model to accurately compute the variable size of the width of the beam (footprint) on the receiver plane reflected by the sea surface and the time intervals during which the receiver remains illuminated. Additionally, the model determines the precise position of the reflected beam on the receiver plane and accurately identifies the time intervals during which communication is feasible, offering invaluable insight into the system performance under oceanic wave variability. The results confirmed that oceanic wave variability induces severe misalignment in optical links, creating intermittent opportunities for effective communication. The optical–geometric analysis contributed significantly to understanding the novel impact of ocean waves on NLOS-UOWC systems. These findings enhance the preliminary considerations in NLOS link design, particularly in scenarios with autonomous underwater vehicles in constant motion, aiding in the reduction of pointing errors. © 2025 by the authors.

Paulo Samaniego-Rojas

PhD Student

PhD student at the University of Málaga working on wireless optical communications, with interest in experimental optical links, underwater optical wireless communications, channel emulation and real-time system implementation.

José María Garrido-Balsells

Professor of Telecommunications Engineering

Professor at the University of Málaga working on wireless optical communications, free-space optical links, underwater optical wireless communications, optical channel modelling and experimental communication systems.

Beatriz del Castillo-Vázquez

Associate Professor of Telecommunications Engineering

Associate Professor at the University of Málaga working on wireless optical communications, free-space optical links, underwater optical wireless communications, optical channel modelling and system-level performance analysis.

Antonio Puerta-Notario

Emeritus Professor / Senior Researcher

Emeritus Professor at the University of Málaga with a long-standing research activity in signal theory, optical wireless communications, visible light communications, free-space optical links and communication system modelling.

Antonio García-Zambrana

Professor of Telecommunications Engineering

Professor at the University of Málaga working on wireless optical communications, free-space optical links, underwater optical wireless communications, visible light communications, and FPGA/RFSoC-based real-time prototyping.