In this internet-connected age, all of our devices are constantly
communicating with each other. Chances are you've got a phone, a laptop, a television, a car radio, maybe a smart home device or some other WiFi-capable appliance, along with a smartwatch or Bluetooth speaker. All of these devices are talking with each other and the wider world constantly.This is all done through radio signals. All of your devices communicate by sending and receiving radio signals at specific frequencies. But why don't cellphone calls collide against Wi-Fi signals? Mostly, it's because there are agreed-upon standards for what devices get to broadcast at what frequency. The radio spectrum is heavily partitioned so different kinds of traffic stay in their own lanes and all the data gets where it needs to go.A similar situation is playing out underwater. Under the sea, there are submarines, research vessels, robots, buoys, and tracking tags on animals, and they've all got to communicate. But radio signals don't work underwater, so the established radio communication standards are useless. Instead, underwater signals are sent via acoustic waves, but until recently there was no standard for which frequencies to use.
That's all been changed now, thanks to a new standard being pioneered by NATO. Called JANUS—after the Roman god of gateways—the new system partitions the range of possible underwater communication frequencies and lets everything communicate with everything else.The JANUS protocol establishes a single frequency—11.5 kilohertz—that is reserved for initial communication between two systems, as well as frequencies for announcing a system's presence to everyone nearby. Once two crafts or robots make contact with each other, they can switch to a different frequency for extended communication.JANUS is opening the door to a better way to communicate underwater. Because of this new standard, all kinds of new collaborations are now possible. Entire fleets of robots can communicate with each other at a distance, communications buoys can send signals from the air into the water, and everyone can finally talk to one another.
