Low-Power Mixed-Signal System for Processing Electric Network Frequency in IoT Devices
Charana S. S. Sonnadara, Mudi Zhang, Min Hua Wu, Sahil S. Shah · 2023
Internet-of-Thing (IoT) devices are ubiquitously used for monitoring critical infrastructures such as data centers, clean rooms, and healthcare facilities. Significant effort is made to authenticate and attest data generated by the sensors onboard the IoT device. Power signature is a promising modality to spatially and temporally localize the data generated by such IoT devices. Specifically, Electric Network Frequency (ENF) extracted from devices that are powered using the electric grid is used to verify the location of the sensor. This article presents a proof-of-concept low-power mixed-signal method to extract the ENF signal and authenticate the device's location. The system utilizes two Gm-C band-pass filters with Winner Take All circuits to estimate the device's location crudely. The entire system consumes a power of 12.2uW to extract the ENF signal.