Acoustic power and communication for extreme IoT

The Internet of Things (IoT) is expanding rapidly, enabled by advances in low-power electronics and an increasing demand for data-driven artificial intelligence. Yet, traditional wireless IoT technologies (e.g., Wi-Fi, Bluetooth, and inductive charging) are largely confined to air and fail in challenging environments like water, biological tissue, or metal. These domains are often inaccessible or remote, making wired power delivery or battery replacement impractical. In this talk, I present recent work using ultrasound as a medium for both wireless power delivery and data communication in such extreme environments. I examine the unique physical constraints that limit range, power transfer efficiency, and data throughput across various media, and outline common modeling and co-design approaches for optimizing the acoustic and system-level performance of IoT nodes. Next, I present emerging technologies that we developed to address these limitations, including 3-D-printed acoustic metamaterials for wave focusing and enhanced power efficiency, ultrasonic backscatter communication for low-power data transfer, low-power acoustic arrays for increasing range, and smart transducer design for simultaneous power and data operation. These advances support the deployment of intelligent, batteryless IoT nodes in these extreme environments, opening new possibilities for underwater networks, implantable biomedical devices, and infrastructure monitoring.