Low-cost one-bit MEMS microphone arrays for in-air acoustic imaging using FPGA's

Recent advancements in MEMS microphone integration have led to the production of low-cost digital MEMS microphones which are suitable for applications in the ultrasonic acoustic spectrum. Using these microphones instead of their analog counterparts can greatly simplify board- and system-design and reduce overall construction cost of an array built with these sensors. In this paper we will propose an architecture for using these low-cost one-bit MEMS microphones to construct a microphone array and demonstrate their applicability in beamforming-based acoustic imaging algorithms targeted at 3D sonar sensors. We developed a small prototype array do demonstrate that these microphones are well suited for array applications, and the proposed system architecture, developed around an FPGA-SOC, is shown to be ideally suited to interface with a large number of these microphones.