Much of underwater wireless communication, so far, has been attributed to the use of acoustic frequencies due to the significantly low absorption than radio frequencies (RF). Ongoing advances in using light for communication through the concept of visible light communication (VLC) make optical wireless relevant to advancing the state--of--the-- art in underwater wireless communication systems. The optical spectrum presents a favorable mode for communicating underwater due to the low signal absorption levels, particularly in the ultraviolet, violet, blue and green wavelengths. Prior work in underwater VLC has largely been theoretical and this research takes a radical high-risk approach to develop empirical models for underwater VLC across real-world configurations and settings. The research takes a transformative approach and explores photo-acoustic hybrid communication in which acoustic and optical wireless communication modes co-exist and complement each other. Photo-acoustic underwater communication modalities can help advance plethora of applications including underwater navigation, exploration, sensing and tactical communications. This research advances the field of underwater networking by bridging the knowledge gap in building realistic underwater photo-acoustic systems through extensive experimentation in real-world conditions and creates a rich open public dataset. This research maintains a strategic collaboration with the Gwinnett County Water Innovation Center near Atlanta, Georgia, thus expanding the outreach of this work and advancing underwater research using advanced facilities. In addition to dissemination of research outcomes through publications, the research involves female student groups from the university Girls-Who-Code (GWC) chapter in underwater research data collection and experiments.
The intellectual merits of this research are derived along two thrusts executed over a 2-year timeline: Thrust 1 - Empirical Modeling of Underwater VLC Channels. This thrust focuses on extensive underwater channel modeling experimentation and data collection in lab and real-world underwater sites. The data points are used to perform empirical modeling of underwater VLC channels along various spatial dimensions (horizontal, vertical, line-of-sight, non line-of-sight), along different physical parameters (salinity, turbidity, temperature and oiliness), and in mobile scenarios. Thrust 2 - Photo-Acoustic Underwater Communication Feasibility Studies. This thrust focuses on the feasibility of integrating the hardware and software of optical wireless (UV and VLC), with acoustic systems. The research conducts experiments across different use-cases for photo-acoustic communication and sensing, particularly for navigation and tracking and device-device communication. In summary, the key outcomes of this research include empirical models for underwater VLC channels, insights from photo-acoustic communication feasibility experimental studies and open datasets for underwater VLC.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.