Abstract
The misalignment of mobile underwater wireless optical communication (UWOC) systems, compounded by turbulence in underwater scenarios, is a practical problem that can be resolved through various means. This work describes a pulse-position-modulation-based (PPM-based) diffused-line-of-sight UWOC system that offers a solution to this issue. PPM is found to be power-efficient and, in terms of bit-error-ratio performance, outperforms on-off keying modulation and orthogonal frequency-division multiplexing modulation in complex dynamic underwater channels. Through indoor experiments and outdoor deployment, we validated the robustness of the proposed PPM-based mobile UWOC system. This work sheds light on the practical implementation of UWOC networks for relieving the strict pointing-acquisition-and-tracking requirements when an underwater apparatus is transmitting or receiving signals on the fly.
Highlights
Underwater sensor networks (USNs) are essential components in the growing demand to monitor the oceans for commercial, scientific, and military purposes
This paper reports the first experimental study of how mobility affects underwater wireless optical communication (UWOC) systems by focusing on the performance of various signal modulation schemes when a communication apparatus is moving at varying speeds
We propose the use of Pulse-position modulation (PPM) in the case of a mobile link in complex dynamic underwater channels taking advantage of DLOS broad beam laser-based communication
Summary
Underwater sensor networks (USNs) are essential components in the growing demand to monitor the oceans for commercial, scientific, and military purposes. Underwater wireless optical communication (UWOC) offers a transformative alternative for IoUT because of its high transmission speeds (∼ 2.25 × 108 m/s), large bandwidth (GHz), high power efficiency, and medium-range working distances (tens to hundreds of meters) [7]–[14]. These merits are favorable for increasing the capacity of the UWOC system, which results in the possibility of building large-scale USNs. The modulation scheme plays an important role in UWOC. Studies that applied Pulse-position modulation (PPM) and orthogonal frequency-division multiplexing (OFDM) modulation have demonstrated high data rates and relatively long-distance communication in stationary indoor-setup. Our results show that by using PPM, a DLOS UWOC system carried by an ROV could be more reliably applied in real underwater scenarios
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
