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arXiv · 2609.29214

From WPT to Encrypted Telemetry: A Battery-Free Backscattering-based Polarimetric Wireless Sensor

Taki Eddine Djidjekh·Loïc Thomas·Quentin Bernyer·Gaël Loubet·Daniela Dragomirescu·Alexandru Takacs
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Abstract

This work introduces an indoor Battery-Free Wireless Sensing Node powered through radiative Wireless Power Transfer (WPT). The proposed platform targets secure, energyefficient active sensing and overcomes key limitations of many prior battery-free approaches, which commonly provide neither on-node computation nor cryptographic protection. The node combines temperature, humidity, pressure and Volatile Organic Compound (VOC) measurements with a low-power microcontroller that executes sensor calibration, derives a VOC index, formats the payload, and applies AES-128 encryption before wireless transmission. Energy harvesting and communication are enabled by a 1-bit controlled Backscatter Rectenna (BR), which both scavenges incident RF power and produces an orthogonally polarized backscattered signal for robust polarimetric operation. Experimental results validate reliable multi-sensor readout and encrypted data transfer, while maintaining a very low energy budget for the complete sense-compute-encrypt-transmit cycle.

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Taki Eddine Djidjekh, Loïc Thomas, Quentin Bernyer, Gaël Loubet, Daniela Dragomirescu, Alexandru Takacs. 2026-09-24. From WPT to Encrypted Telemetry: A Battery-Free Backscattering-based Polarimetric Wireless Sensor. https://arxiv.org/abs/2609.29214

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