A Novel Dual-Key Authentication via Wireless Power Transfer for Secure SWIPT-Based IoT Systems

This article presents a novel mechanism to enhance security of battery-free, wirelessly powered IoT devices, in line with the Simultaneous Wireless Information and Power Transfer paradigm. The proposed authentication method uses a combination of public and private keys implemented on the Wireless Power Transfer link enabled by the backscattering of the power wave. This mechanism operates independently of the wireless communication protocol, ensuring a universal compatibility across IoT devices without increasing their energy consumption. This approach has been implemented and tested on a battery-free wireless Sensing Node within a LoRaWAN-based Wireless Sensor Network. The power wave is modulated with a digital Public Key by the power source, and a digital Private Key is generated by the Backscattering Rectifier of the battery-free wireless Sensing Node to guarantee a dynamic authentication frame to prevent it from being copied and reused in replay attacks.