Evaluation of UW-Lidar system performance under various conditions

Abstract

Optical underwater communication offers significant advantages over conventional acoustic communication, including elevated data speeds, reduced latency, lower power usage, and a more compact design. Construction complexity and safety requirements are constantly increasing as the world expands its underwater infrastructure. Water type, absorption, scattering, and other propagation losses influence the distance and range of optical beams underwater.

This study presents the simulation and design of an underwater light detection and ranging (UW-Lidar) system, which is based on a special design of an optical frequency generator (OFsG) system. Our goal is to enhance the performance of Lidar for underwater applications, specifically in terms of target detector precision. We also investigated the system performance for various conditions, such as different laser beam sources, seawater shallow degrees, and target distances. We utilized Distributed Bragg reflector (DBR) lasers as optical sources, emitting 10 mW of power in the visible spectrum range, specifically the blue-green wavelengths. These wavelengths have low attenuation and can allow for high-bandwidth transmission over short distances. We tested the proposed system’s performance in detecting targets at varying distances (20–40–60 m) in various shallow seawaters for different laser beam source based on Doppler frequency shift between transmitted and reflected signal. The results indicate that the best system performance is when the laser frequency belongs to 550 THz. This system can detect the targets with good received power and an accuracy of up to 0.0414 m in pure water and 0.8513 m in turbid water. The proposed system was simulated used VPI design suite 9.8.