Multi-Modal NFC for Industrial Sensors

Near-field communication (NFC) is increasingly being explored for sensing and embedded system applications beyond consumer smartphones, particularly in domains such as smart factories and smart lighting. However, existing NFC deployments are constrained by the limited range, power delivery, and communication reliability of portable readers, restricting their applicability in industrial systems requiring battery-less operation and real-time data exchange. This paper presents a Passive-Active NFC framework for battery-less sensing and embedded applications, enabled by energy-harvesting NFC integrated circuits (ICs) and ultra-low-power microcontrollers. The framework defines four operational states: Static Passive, Static Active, Dynamic Passive (batteryless), and Dynamic Active, allowing flexible transitions between sensing, computation, and communication modes. Experimental evaluation is conducted using industrial Type 5 NFC ICs and both handheld and industrial NFC readers, with analysis of power consumption, communication range, reliability, and data integrity. To support reliable data transfer, a novel NFC Communication Control Protocol is introduced to mitigate corruption during dynamic operation and concurrent communication events. Results demonstrate that industrial NFC readers can extend batteryless operating range up to an order of magnitude compared to consumer devices, while maintaining reliable data acquisition and transmission. The proposed framework enables robust batteryless sensing systems suitable for industrial applications.