Electronic warfare and its permutations have long been an interest of mine; in fact, back in the 1980's, they were part of my job. My knowledge of the field is long out of date, of course. Computers, microprocessors and distributed processing have altered it out of almost all recognition compared to the equipment I used, which seems almost steam-driven by comparison . . . but many of the basic tasks of electronic warfare remain the same.
One of the most important is to deny the enemy the ability to communicate. If his sensors can't warn of an incoming threat, or his ships, aircraft and other units can't tell each other what they're doing or where they're going, all sorts of complications result. That's why the Defense Advanced Research Projects Agency (DARPA) has been working on an emergency communications system for the US Navy, designed to temporarily replace existing networks when they're taken down by enemy action or otherwise unusable. In a press release, DARPA says:
DARPA’s Tactical Undersea Network Architecture (TUNA) program ... seeks to develop and demonstrate novel, optical-fiber-based technology options and designs to temporarily restore radio frequency (RF) tactical data networks in a contested environment via an undersea optical fiber backbone.
The concept involves deploying RF network node buoys—dropped from aircraft or ships, for example—that would be connected via thin underwater fiber-optic cables. The very-small-diameter fiber-optic cables being developed are designed to last 30 days in the rough ocean environment—long enough to provide essential connectivity until primary methods of communications are restored.
There's more at the link.
Here's a video showing what DARPA has in mind.
That's some seriously impressive skull-sweat. A fiber-optic cable can't be jammed or interfered with, apart from cutting it; and small surface buoys linked by trailing, underwater fiber-optic cables will be very hard to even detect, let alone disrupt. If DARPA and the US Navy can figure out ways of deploying them that an enemy can't stop, or use to track them down and destroy them, this will be a game-changer in tactical naval communications. They might even be able to add an underwater communications component to them, so that submarines can use the network to talk to surface ships, aircraft, or even their home bases.
This is pretty nifty. Congratulations to all concerned.