Criminal activity is increasingly entering the ocean subsurface with acts such as illegal fishing and narco-submarining becoming points of contention. This among other illicit acts taking place in this domain imply a need for surveillance to render these activities apparent. However, subsurface Underwater Sensor Networking which is central to the surveillance is still generations behind terrestrial networking, therefore it is still challenging to monitor for subsurface activities. This is since the current signal transmission standard, acoustic communication, is limited in practical bandwidth and thus channel data-rate, this is, however, caveated with omni-directional propagation and supreme range rendering it reliable but incapable of carrying video or other data intensive sensor information. There is, however, an emerging technology based on optical (visible light) communication that can accommodate surveillance applications with superior data rates and energy savings. This investigation demonstrates how theoretically it is possible to achieve a network of underwater channels capable of sustaining a multimedia feed for monitoring subsurface activity using modern optical communication when in compared to an acoustic network. In addition, a simple topology was investigated that shows how the range limitations of this signaling can be extended by adding floating relay nodes. Through simulations in Network Simulator 3 (NS-3)/Aquasim-NG software it is shown that Visible Light wireless communication in visible light networks have a channel capacity high enough to carry out monitoring in strategic areas, referencing, optical modems that are available in the market. This implies that data-rates of 10 Mb/s are possible for the real-time video surveillance.
STEWART, C., FOUGH, N. and PRABHU, R. 2022. A simulation into the physical and network layers of optical communication network for the subsea video surveillance of illicit activity. In Bouma, H., Prabhu, R., Stokes, R.J. and Yitzhaky, Y. (eds.) Counterterrorism, crime fighting, forensics, and surveillance technologies VI: proceedings of the 6th Counterterrorism, crime fighting, forensics, and surveillance technologies, co-located with SPIE (Society of Photo-optical Instrumentation Engineers) Security + defence conference 2022, 5-6 September 2022, Berlin, Germany. Proceedings of SPIE, 12275. Bellingham, WA: SPIE [online], article 1227508. Available from: https://doi.org/10.1117/12.2641374