If truth is the first casualty of war, then communications come a close second. To keep the US Navy and allied fleets operating when data systems are disrupted, DARPA is conducting its Tactical Undersea Network Architectures (TUNA) program, which has completed its first phase of development. The tactical data network uses a system of rapidly-deployable buoys and advanced fiber optic technology to temporarily reestablish data networks at sea, that may have been destroyed due to enemy action or other forces.
According to DARPA, TUNA is a self-powering, quickly-deployable RF network that uses buoys connected by thin underwater fiber optic cables that are designed to last up to 30 days – the agency believes is enough time to bring the damaged primary network back online. The recently completed Phase 1 was intended to develop concepts and technologies in the fields of modelling and simulation, as well as at-sea testing of the buoys and cables.
A major part of this phase was finding a way of powering the network. The University of Washington's Applied Physics Laboratory (APL) found a solution in its Wave Energy Buoys that Self-deploy (WEBS). Designed to be folded into a cylinder that can be dropped from a ship or aircraft, these buoys are a triangle of floats that scissor in and out as they ride on the waves, to generate electricity for the data system.
DARPA says that TUNA Phase 2 will involve building an end-to-end system for laboratory and sea evaluation.
The video below describes TUNA and Phase 1 of its development.
Source: DARPA