Underwater wireless communication is essential for monitoring and protecting critical subsea infrastructures, but the ocean is a very hostile environment for signals. Unlike in the air, underwater communication systems must deal with strong signal loss, limited bandwidth, long delays, low data rates, high error rates and significant background noise.

The publication “Underwater communication system technologies” reviews the three main families of underwater communication: acoustic, electromagnetic (EM) and optical systems. It explains how each technology works, which physical properties of seawater affect it, and why their performance is very different from what we expect from terrestrial and aerial communication networks.

For UnderSec, this overview provides a shared technical baseline for choosing and combining the right technologies to support surveillance, sensing and secure communications around underwater critical infrastructure. Understanding these constraints is key to designing realistic systems for subsea security, rather than assuming that “underwater 5G” will behave like land-based networks.