Dolphin 'sonar' inspires clutter-penetrating radar

The twin inverted pulse radar (TWIPR) is reportedly able to distinguish true ‘targets’, such as certain types of electronic circuits that may be used in explosive or espionage devices, from ‘clutter’ (usually other metallic items) that may be mistaken for a genuine target by traditional radar and metal detectors.

The new system has been developed by a team led by Prof Tim Leighton from Southampton University’s Institute of Sound and Vibration Research and is based on twin inverted pulse sonar (TWIPS).

TWIPS exploits the natural abilities of dolphins to process their sonar signals to distinguish between targets and clutter in bubbly water. Some dolphins have been observed to blow ‘bubble nets’ around schools of fish, which force the fish to cluster together, and their sonar would not work if they could not distinguish the fish from the bubbles.

The technique uses a signal consisting of two pulses in quick succession, one identical to the other, but phase inverted. Prof Leighton, along with Prof Paul White and students Dan Finfer and Gim Hwa Chua, showed that TWIPS could enhance linear scatter from the target, while simultaneously suppressing nonlinear scattering from oceanic bubbles.