A biomimetic coupled circuit based microphone array inspired by the fly Ormia ochracea

Miniaturization of microphone arrays poses challenges to attain accurate localization performance due to shrinking aperture. The fly Ormia ochracea is able to determine the direction of sound source with an astonishing degree of precision，even though its ears are extremely small. Inspired by this, an equivalent analog circuit is designed to mimic the coupled ear system of the fly for sound source localization. This coupled circuit receives two signals with tiny phase difference from a space closed two-microphone array, and produces two signals with obvious intensity difference. The response sensitivity can be adjusted through the coupled circuit parameters. The directional characteristics of the coupled circuit have been demonstrated in the experiment. The designed miniature microphone array can localize the sound source with low computational burden by using the intensity difference. This system has significant advantages in various applications where the array size is limited.