The DDD (Dolphin Deterrent Device) is an equipment able to keep the dolphins away from fishing nets, thanks to an efficient technique of interaction with their echo-localization system (sonar).
The DDD is an electronic device with a 16 bit microprocessor that controls the emission circuit for the randomization of the signals and the power part with the output transducer.
It is powered by internal (sealed) rechargeable batteries and generates an acoustic signal in case of insufficient charge.
The DDD are fixed to fishing equipment (nets, longlines, etc) and are activated automatically in contact with water. The position of DDDs in the networks varies depending on the type of fishing.
The level of the DDD emissions doesn’t produce any harm to mammals or fish; these last are insensitive to the frequencies emitted