Microstructure-guided spatial sensing for low-power IoT

Abstract

This demonstration presents a working prototype of Owlet, an alternative design for spatial sensing of acoustic signals. To overcome the fundamental limitations in form-factor, power consumption, and hardware requirements with array-based techniques, Owlet explores wave's interaction with acoustic structures for sensing. By combining passive acoustic microstructures with microphones, we envision achieving the same functionalities as microphone and speaker arrays with less power consumption and in a smaller form factor. Our design uses a 3D-printed metamaterial structure over a microphone to introduce a carefully designed spatial signature to the recorded signal. Owlet prototype shows 3.6° median error in Direction-of-Arrival (DoA) estimation and 10 cm median error in source localization while using a 1.5cm × 1.3cm acoustic structure for sensing.