Flexible, Compact Acoustic Transducer Arrays

For military applications, acoustic arrays can provide target signatures and locations of aircrafts, vehicles, weapons and personnel. Additional benefits of arrays include immunity to jamming, low cost, low weight and low power consumption. Acoustic beamforming using conventional arrays typically require 10~100s of microphones and have an aperture size ranging from several inches to several feet. Conventional acoustic arrays have seen limited usage in aerial reconnaissance for Army applications due to the size requirements for beamforming. While the size requirements for beamforming is somewhat constrained by the aperture, the array size can be miniaturized by microfabricated microphones and made conformal to a curved surface through the use of a flexible substrate. Our proposed solution is to implement an acoustic array design for broadband using microelectromechanical systems (MEMS)-based, piezoelectric microphones mounted on a compact, flexible substrate. Additional features of the array include a hybrid electronics packaging for signal conditioning and acoustic metamaterials for array performance enhancement. The development of a compact, flexible acoustic array is ideal for small UAS platform where conventional acoustic arrays are impractical.