DARPA’s TUNA program develops fiber optical undersea communication Network for backup in contested environment

The capability of Russia and China to disrupt American military wireless and satellite communications using electronic warfare has been rising.  This is athreat to US Navy operations that require connectivity among a diverse set of platforms, including submarines, surface ships, aircraft, and shore sites. The links among these platforms support a wide range of applications, including command and control, battle management, the dissemination of common operational and tactical pictures, sensor-data dissemination, the tracking and engagement of time-sensitive and other targets, and many other C4ISR functions.

One of the measures Defense Department is taking is to develop a rapidly deployable high speed backup data network . DARPA launched  Tactical Undersea Network Architectures (TUNA) program  in 2015 that seeked to develop and demonstrate novel technology options and designs to  for existing tactical data networks in a contested environment using small diameter optical fiber and buoy relay nodes.   DARPA developed a network of  “radio relay mounted on sea buoy”, deployed from ships or planes, that are tethered together by fiber optic cables to create  data network. These very-small-diameter fiber-optic cables will be able to last 30 days in the rough ocean environment, which is long enough to provide essential connectivity until primary methods of communications are restored.

“SATCOM has its limitations. Signal isn’t always available, and there are constraints on the speed and volume of communications.” “The goal of the DARPA’s Tactical Undersea Network Architectures (TUNA) program is to ensure that US forces retain an information advantage even in contested environments where potential adversaries may attempt to disrupt other communication channels,” said LGS Innovations CEO Kevin Kelly.

DARPA’s Tactical Undersea Network Architecture (TUNA) program  completed its initial phase in 2017, successfully developing concepts and technologies aimed at restoring connectivity for U.S. forces when traditional tactical networks are knocked offline or otherwise unavailable. “Phase 1 of the program included successful modeling, simulation, and at-sea tests of unique fiber-cable and buoy-component technologies needed to make such an undersea architecture work,” said John Kamp, program manager in DARPA’s Strategic Technology Office. “Teams were able to design strong, hair-thin, buoyant fiber-optic cables able to withstand the pressure, saltwater, and currents of the ocean, as well as develop novel power generation concepts.”

The program entered the next phase in 2017, which calls for the demonstration of a prototype of the system at sea. Having now entered its second and final phase, the program is advancing to design and implement an integrated end-to-end system, and to test and evaluate this system in laboratory and at-sea demonstrations. In this next phase Oceaneering experts demonstrated a prototype of the system at sea. The project aims at using optical fiber to restore radio frequency (RF) tactical data networks temporarily in a contested environment via an undersea optical fiber backbone. As a test case for the TUNA concept, teams are using Link 16—a common tactical data network used by U.S. and allied forces’ aircraft, ships, and ground vehicles.

One of the important component of  U.S. Navy’s, maritime strategy is “All Domain Access,” whose one of its five pillars is Assured command and control, which requires US communications networks to operate reliably and securely in the face of enemy jamming and hacking. Navy is also developing optically tethered communications buoys for communications with military satellites, a retrievable tethered fiber optic buoy for communications and surveillance between submarine and satellite. Navy is also developing an integrated Network of distributed and netted sensors with unmanned underwater vehicles (UUVs), submarines, and surface and aerial platforms. The objective is to gain situational awareness of the undersea battlespace to locate and engage threats rapidly in littoral areas. The network elements shall be connected by mobile ad hoc network of wireless nodes that can function cooperatively and spontaneously without a fixed infrastructure.