Sweat-Powered, mm-Scale, Continuous-Time Sensor Systems With Bluetooth Low Energy (BLE) Backscatter
Jordan S. Besnoff, Hongtao Zhong, Shian Su, Kaveti Rajaram, Nitin Maiya, Supriya Krishna, Nate T. Garland, Amay Jairaj Bandodkar, David S. Ricketts · IEEE Access · 2024
Personal healthcare monitoring is a promising field, as continuous, individual-specific, real-time health information can enable better care and more precise diagnoses. One barrier to continuous monitoring lies in the power requirements and data retrieval needed for on-body sensors, as well as the need for measurements in different locations on the body. Ideally, these sensors would be self-powered, unobtrusive, and compatible with low-power communication systems. However, existing wireless self-powered on-body sensors are often limited by energy constraints, making real-time data transfer challenging with conventional Bluetooth communications. In this work, we present a wearable, self-powered on-body sensor system that utilizes an ultra-low-power backscatter radio scheme to enable real-time wireless communication, powered by sweat batteries, thus eliminating the need for external power. We demonstrate the capabilities of this system with a continuous, real-time electrocardiogram (ECG) system that transmits data to a cell phone held by the user.