Work

GS-Tag: Design of a Generic Sensor Tag Based on RF Switches and COTS RFID System

Year: 2025

Type: article

Abstract: With the development of the Internet of Things (IoT), substantial research efforts have been devoted to extending the sensing capability of commercial off-the-shelf (COTS) radio-frequency identification (RFID) tags. State-of-the-art approaches either demand sophisticated hardware redesign or are constrained to specific sensing capability, leading to increased costs and limited scalability. In this paper, we present the design of a generic sensor tag (GS-Tag) based on RF switches and COTS RFID system for transmission of generic sensor data. RF switches are connected in parallel with the RFID chip, and the GS-Tag modulates the sensor data by controlling the RF switches. Specifically, with the RF switches turned on, the tag’s chip is short-circuited, rendering it unreadable; conversely, turning off the RF switches makes the tag readable. The reader demodulates the data through the compatible electronic product code (EPC) protocol. A subtle dual RF switch scheme is adopted to extend the communication range. In addition to the battery-powered solution, we integrate an RF energy-harvesting module, develop a high-efficiency energy management circuit, and design an efficient task scheduling strategy to enable the GS-Tag to operate in a battery-free mode. We implement a prototype of GS-Tag with COTS RFID devices. Comprehensive experiments demonstrate that our designed GS-Tag can achieve an average packet reception rate (PRR) exceeding 99%, exhibits robustness to environmental disturbance, and facilitates coexistence of six GS-Tags with an average PRR of over 91%. Due to the dual RF switch scheme, the communication range of GS-Tag extends to 12 m. Besides, GS-Tag has an extremely low power consumption of just 3.98 μ W. A practical application is developed to accurately monitor temperature and ambient light intensity in an office environment while maintaining low power consumption. Our designed GS-Tag presents a cost-effective and compatible solution for expanding the sensing capabilities of COTS RFID system.

Source: ACM Transactions on Sensor Networks

DOI: 10.1145/3744563