Like a watchdog

Cerberus is the name of the hellhound in Greek mythology. He guards the entrance to the underworld and makes sure that nobody escapes. Atlas Elektronik UK, based in Dorchester, England, named its sonar Cerberus by analogy. This seems to make sense, as Cerberus keeps watch deep down, under water.
You don't have to anchor off the coast of Somalia or seek peace and quiet in the Strait of Malacca to protect yourself against uninvited visitors from the maritime underworld. Diving equipment is now available and affordable almost everywhere, criminal energy is free, and opportunity makes thieves, even in the Mediterranean and the Caribbean.

And because yacht owners, captains and crews not only want to be warned of thieves in good time, the British have now channelled their experience with military equipment into the crew-friendly Cerberus Yacht Sonar. With a diameter of 30 centimetres and a slightly greater height, the useful warning device is not much larger than a wastepaper basket and, at 23 kilograms, is only slightly heavier, and is in any case portable for yacht and crew in every respect. The device reports the sounds and resonances of a diver from the Cerberus stand - or rather, hanging location - up to one nautical mile away. Cerberus hangs with its cable at depths of up to 75 metres.

The crew can track the movement of the diving object on a monitor. The system works both as a stand-alone solution and integrated into other safety technology such as video surveillance. Cerberus not only detects divers, but also swimmers and large and small underwater vehicles. The small buoy can also distinguish between fish and keel and stern water noises. This reduces false alarms.

A signal can be set for the approach of an object as well as for movement away from the yacht, for example a guest snorkelling out of the safety area around the yacht.
Cerberus also registers multiple signals at any time and tracks their movements. With Cerberus, Atlas Elektronik always increases caution on yachts. That much is certain.