RFID-based Respiration Monitoring using Temperature Sensing

Abnormal breathing can be a symptom of unhealthy status, but conventional diagnostic exams involve cumbersome and intrusive instrumentation. Wireless wearable technologies may hence provide an attractive alternative, but state-of-the-art solutions are generally bulky, include complex electronics, and require a local power source to communicate by using a BLE (Bluetooth Low Energy) interface. Epidermal battery-less devices enabled by Radio Frequency IDentification (RFID) technology are instead gaining increasing interest. Indeed, data sensing and transmission become fully wireless, and the electronic complexity can be kept small thanks to new generation RFID Integrated Circuits (ICs) that are provided with built-in sensors. In particular, this paper will focus on the latest advancements in the field of RFID breath sensor-devices that wirelessly monitor respiration by measuring the temperature gradients of the air flowing through the airways. The main innovations span from improvements in the lightweight design of the devices and materials, the enhancement of the sensing capabilities by doubling the embedded sensors on the same device, and, most importantly, the thorough experimentation performed to assess the clinical meaningfulness of temperature breathing waveforms with respect to conventional clinical-grade flow-based methods.