Francesca M. C. Nanni;Alessio Mostaccio;Gaetano Marrocco
{"title":"Comparative Evaluation of Impedance-Matching Techniques for Sustainable Laser-Induced Graphene (LIG) UHF RFID Antennas","authors":"Francesca M. C. Nanni;Alessio Mostaccio;Gaetano Marrocco","doi":"10.1109/JRFID.2026.3654752","DOIUrl":"https://doi.org/10.1109/JRFID.2026.3654752","url":null,"abstract":"As the demand for RFID-enabled systems grows, sustainability and circularity are becoming key drivers of innovation in tag and antenna design. Laser-Induced Graphene (LIG) offers a low-impact and recyclable alternative to metal conductors, enabling green, chemical-free, and energy-efficient fabrication compatible with eco-friendly substrates and material recovery. Yet, its high surface resistance limits radiation efficiency and complicates impedance matching with highly reactive UHF-RFID chips. This work presents a numerical and experimental comparison of distributed and lumped matching techniques for LIG dipoles, quantifying their contribution to power loss and overall efficiency. Distributed networks (e.g., T-match, notch) introduce large insertion losses (10–20 dB) due to differential-mode currents, while lumped configurations minimize energy dissipation and preserve material efficiency. The best trade-off between performance and sustainability is obtained with a single inductor (enabling realized gains around −5 dBi) for medium impedances, whereas for loads with a very low real part, an eventually reusable small metallic loop is required to ensure conjugate matching with negligible environmental impact. The proposed guidelines enable energy- and material-efficient LIG-based RFID antennas, offering a practical route toward eco-compatible and circular wireless systems that combine high RF performance with sustainable design principles.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"10 ","pages":"66-75"},"PeriodicalIF":3.4,"publicationDate":"2026-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146082261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"RF-TCNet: A Lightweight Topology Compression Network for Drone RF Fingerprint Identification","authors":"Shun Zuo;Xianmin Bai;Chenxu Zhang;Yi Liu;Chunli Wang;Yanjun Zhang","doi":"10.1109/JRFID.2026.3654664","DOIUrl":"https://doi.org/10.1109/JRFID.2026.3654664","url":null,"abstract":"As drones become increasingly prevalent in both civilian and military applications, identifying their Radio Frequency (RF) characteristics is critical for airspace security and drone management. This paper proposes a lightweight network architecture RF-TCNet for drone RF fingerprint identification. A preprocessing method called Energy-Calibration Spectrum Generation (ECSG) is developed, which uses the global maximum amplitude to calibrate the spectrum energy and enhances feature contrast using decibel (dB) scaling transform to generate high-quality training data. Subsequently, the RF-TCNet is used for classification, which has approximately 0.1 M trainable parameters. Its core modules include Dynamic Frequency Attention (DFA) that emphasizes critical frequency elements and Energy Topology Pooling (ETP) that amplifies high-energy regions by eliminating redundant data. Experiments conducted on the DroneRFa and DroneRF datasets show that ECSG improved classification accuracy by 6.14% and 9.85%, respectively, compared to traditional preprocessing methods. With RF-TCNet, we achieve classification accuracies of 99.97% and 94.89% on these datasets while maintaining an extremely low number of parameters. The work improves the performance of drone RF signal recognition through efficient lightweight design and targeted preprocessing methods, providing a potential solution for resource constrained scenarios.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"10 ","pages":"76-89"},"PeriodicalIF":3.4,"publicationDate":"2026-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146082258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dual-Band Passive BLE Backscatter Tag With Clock-Coordinated Modulation","authors":"Diming Lin;Xiaoming Li;Xinkai Zhen;Jiawei He","doi":"10.1109/JRFID.2026.3653955","DOIUrl":"https://doi.org/10.1109/JRFID.2026.3653955","url":null,"abstract":"The large-scale deployment of Internet of Things (IoT) nodes has made low power consumption and high device compatibility key issues. The prevailing communication protocol for passive IoT devices is ISO/IEC 18000-6C. However, this protocol can only be implemented on the business side via dedicated readers, limiting its popularity among consumers. Bluetooth Low Energy (BLE) is by far the most common type of connection. However, it requires a crystal oscillator to generate the necessary high-precision clock signal. For passive applications, using a crystal oscillator increases power consumption, cost and size. This paper addresses the integration of BLE uplink logic into RFID tag chips by providing a high-precision BLE clock via an air interface using clock-coordinated modulated wave technology. This enables passive IoT tags to access common consumer smart devices. A dual-band passive chip has been fabricated using the TSMC <inline-formula> <tex-math>$0.18~mu $ </tex-math></inline-formula>m process. The resulting device measures 1.24 mm2, has an average power consumption of <inline-formula> <tex-math>$16.4~mu $ </tex-math></inline-formula>W and a communication range of 12.9 m.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"10 ","pages":"60-65"},"PeriodicalIF":3.4,"publicationDate":"2026-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Guest Editorial Special Issue on the 12th Annual IEEE International Conference on Wireless for Space and Extreme Environments (WiSEE 2024)","authors":"Holger Maune;Eduardo A. Rojas Nastrucci","doi":"10.1109/JRFID.2026.3652935","DOIUrl":"https://doi.org/10.1109/JRFID.2026.3652935","url":null,"abstract":"The IEEE International Conference on Wireless for Space and Extreme Environments (WiSEE) has established itself as a premier interdisciplinary forum for researchers, engineers, and practitioners addressing the unique challenges of wireless technologies operating in space, aerospace, and other harsh or remote environments. Since its inception in 2013, WiSEE has demonstrated steady growth and increasing technical breadth. After the disruptions caused by the COVID-19 pandemic, the 2024 edition of WiSEE clearly reflected the renewed momentum of the community and the continued relevance of research on wireless systems for extreme environments. WiSEE 2024 was co-located with IEEE RFID Conference on RFID Technology and Applications (RFID-TA 2024), further strengthening the interaction between the RFID and wireless-for-extreme-environments research communities.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"10 ","pages":"i-ii"},"PeriodicalIF":3.4,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146175810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Compact Implantable UHF-RFID Rectenna Tag for Implantable Bolus-Based Wireless Animal Tracking","authors":"Supakit Kawdungta;Danai Torrungrueng;Hsi-Tseng Chou","doi":"10.1109/JRFID.2026.3652809","DOIUrl":"https://doi.org/10.1109/JRFID.2026.3652809","url":null,"abstract":"This paper proposes a compact implantable ultra-high frequency (UHF) radio frequency identification (RFID) rectenna tag designed for integration into an implantable bolus for in-body wireless animal tracking. The integrated design achieves dual functionality: passive RFID tag (920–925 MHz) and RF energy harvesting via a Schottky diode rectifier. The rectenna tag structure incorporates a meandered dipole antenna with T-matching, optimized for conjugate impedance matching with a passive RFID chip operating in the 920–925 MHz band. A loop structure is integrated with a Schottky diode to enable RF-to-DC power conversion. Full-wave simulations within high-dielectric media (<inline-formula> <tex-math>$varepsilon text {r} =40$ </tex-math></inline-formula>–80) modeling internal bolus conditions demonstrate an input impedance of 30 + j<inline-formula> <tex-math>$300~Omega $ </tex-math></inline-formula>, exhibiting an omnidirectional radiation pattern with a gain of −19.0 dBi (RFID port) and −18.0 dBi (rectenna port), and a specific absorption rate (SAR) in 1 g of 0.231 W/kg and 0.336 W/kg, respectively. The system demonstrates an RF power harvesting efficiency of up to 10-20%. A prototype was fabricated and tested in water, achieving maximum read ranges of 2.0 m (free space) and 1.4 m (aqueous environment). Measured gains were −15.0 dBi (RFID port) and −18.0 dBi (Rectenna port). The measured SAR also remained at 0.27 W/kg (RFID tag port) and 0.35 W/kg (Rectenna port), well within established safety limits. These results validate the proposed rectenna tag as a promising solution for efficient and safe in-body animal tracking via implantable bolus tags. The system integrates a passive RFID chip and RF-DC rectifier, enabling dual-functionality: battery-free real-time animal identification and self-powered physiological sensing (e.g., rumen temperature/pH) for livestock health monitoring.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"10 ","pages":"47-59"},"PeriodicalIF":3.4,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Edge-Assisted Domain Adaptive Passive RF-Based Sensing for Localization and Activity Recognition","authors":"Ankur Pandey;Mohammad Zeeshan;Joaquín Torres-Sospedra;Atul Kumar;Sudhir Kumar","doi":"10.1109/JRFID.2026.3651054","DOIUrl":"https://doi.org/10.1109/JRFID.2026.3651054","url":null,"abstract":"Ultra-High Frequency (UHF) Radio Frequency Identification (RFID) technology enables scalable, passive device-free location and activity recognition (LAR) in smart warehouses, assisted living environments, and industrial Internet of Things (IoT) through the deployment of commercial off-the-shelf (COTS) readers. However, it is observed that performance degrades across different environments due to domain shifts resulting from changes in shelving layouts, inventory density, metallic interference, tag orientation, worker dynamics, and multi-reader configurations. This work proposes CycleSiamese, a lightweight, class-aware domain adaptation framework suitable for passive RFID systems, which integrates cycle-consistent Received Signal Strength (RSS) transformations with a Siamese classifier, for LAR using minimal labeled target samples. Evaluated on the COTS UHF RFID floor dataset featuring Impinj Monza 4 Quiet Tag (QT) passive tags beneath an apartment floor interrogated by an Impinj Speedway Revolution R420 reader for device-free ambient assisted living monitoring, the proposed method reduces linear inter-personal domain discrepancy from 21.58 to 2.16 (88 % reduction), achieving 82.2 % Human Activity Recognition (HAR) accuracy with limited target samples. Further, the proposed method is successfully validated on three additional Radio Frequency (RF)-based datasets, which include temporal drift, device heterogeneity, and dynamic environments, while supporting real-time edge deployment on resource-constrained RFID gateways.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"10 ","pages":"35-46"},"PeriodicalIF":3.4,"publicationDate":"2026-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145982380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Material Sensing Using Arrays of Open Dipole RAIN RFID Tags","authors":"Fatima Villa-Gonzalez;Rahul Bhattacharyya;Pavel Nikitin","doi":"10.1109/JRFID.2026.3680834","DOIUrl":"https://doi.org/10.1109/JRFID.2026.3680834","url":null,"abstract":"This work demonstrates how open dipole (OD) RAIN RFID tags and tag-arrays can be used for material characterization in a standard compliant way. Unlike T-matched antennas, OD designs exhibit reduced resonance complexity, with a single minimum in the power-on-tag-forward (POTF) and a single maximum in the power-on-tag-reverse (POTR) response. We introduce a setup-invariant metric based on the transmitted and received reader powers at tag threshold, which preserves resonance information while eliminating the need for calibration. In addition, we demonstrate that auto-tune (AT) code changes in self-tuning ICs of OD tags provide clear and narrowband min-max transitions that remain stable over a wide range of transmit powers, providing high tuning flexibility and enabling sensing at fixed reader power. Building on this, we propose a novel approach for material sensing, leveraging the AT-code transitions within the narrow UHF RFID band using arrays of individually tuned OD tags. We demonstrate the repeatability of open dipole-based sensing using 6 commercial OD RAIN RFID tags to estimate the effective dielectric permittivity of 7 materials, obtaining lower variance than T-matched antennas for high <inline-formula> <tex-math>$varepsilon _{r}$ </tex-math></inline-formula> dielectrics. Furthermore, we propose a custom three OD tag array capable of discriminating between four specific materials and air within the UHF band, demonstrating the sensing capability of this new method in compliance with regulatory standards.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"10 ","pages":"287-301"},"PeriodicalIF":3.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147665349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Durable Conductive Ink Enabling Washable Textile Electronics for RFID and WPT Devices","authors":"Yi-Cang Lai;Gaozhi Xiao;Wilson Hou-Sheng Huang","doi":"10.1109/JRFID.2026.3681532","DOIUrl":"https://doi.org/10.1109/JRFID.2026.3681532","url":null,"abstract":"Coil structures are fundamental components in high-frequency (HF) radio frequency identification (RFID) and wireless power transfer (WPT) systems. Integrating such structures into textiles enables new possibilities for wearable and flexible electronic devices. However, washability remains one of the key challenges in textile electronics, since exposure to water, detergent, and mechanical agitation can significantly degrade the performance of conductive materials. In this study, a washable conductive silver–neoprene ink was developed for screen printing textile-based coil structures. The ink formulation was optimized to achieve a balanced combination of electrical conductivity, mechanical flexibility, and strong adhesion to textile substrates. Experimental results show that the printed coils maintain low resistance and stable electrical performance even after multiple laundering cycles. The improved durability originates from the elastomeric neoprene binder, which preserves the conductive network integrity under repeated mechanical deformation and washing. These results demonstrate the potential of the proposed conductive ink for the fabrication of durable textile electronic systems, including wearable RFID tags and textile-integrated wireless charging modules.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"10 ","pages":"324-333"},"PeriodicalIF":3.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147696614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Giovanni Andrea Casula;Giorgio Montisci;Giuseppe Valente
{"title":"A Low-Cost 3D-Printed Broadband Sinusoidal-Shaped Patch Antenna With Coplanar Microstrip Feed","authors":"Giovanni Andrea Casula;Giorgio Montisci;Giuseppe Valente","doi":"10.1109/JRFID.2026.3674681","DOIUrl":"https://doi.org/10.1109/JRFID.2026.3674681","url":null,"abstract":"This paper introduces an advanced architecture for wideband microstrip patch antennas (MPAs) that addresses the intrinsic limitations of narrow impedance bandwidth and significant feed-line losses associated with thick dielectric substrates. The proposed solution integrates two primary innovations: a sinusoidal vertical patch profile, enabled by precision 3-D printing, and a locally hollowed substrate for active loss mitigation. Unlike traditional designs that utilize a uniformly thick dielectric to maximize bandwidth at the expense of efficiency, this approach confines the supporting material strictly to a thin dielectric layer beneath the radiating patch. This structure significantly reduces dielectric losses and suppresses surface wave excitation along the coplanar microstrip feed line. Leveraging this 3-D geometry, wideband impedance matching is achieved using a single open-ended stub integrated within the hollowed region. Experimental results demonstrate a fractional impedance bandwidth exceeding 26.5%, representing a 40% improvement over state-of-the-art coplanar-fed designs and reaching performance levels comparable to more complex, less-integrable coaxial probe-fed antennas. Furthermore, the 3-D curvature effectively reduces the antenna projected resonant size, providing a compact footprint ideal for the high-density integrated circuits of modern communication systems.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"10 ","pages":"232-242"},"PeriodicalIF":3.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147606335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Calibrated IQ Backscatter Modulator and Associated Receiver","authors":"Meng Yang;Nicolas Barbot","doi":"10.1109/JRFID.2026.3675902","DOIUrl":"https://doi.org/10.1109/JRFID.2026.3675902","url":null,"abstract":"In this paper, we present a calibrated IQ backscatter modulator and its associated receiver. The backscatter modulator can generate any impedance value or reflection coefficient. This modulator is controlled by two analog voltages which can be controlled by a simple micro-controller using two digital to analog converters (or two low-pass filtered pulse-width modulation signals). A 2-step calibration procedure allows one to accurately control the impedance and the associated reflection coefficient values to realize any analog or digital backscatter modulation. Moreover, a specific receiver is used to demodulate the backscattered signal produced by this IQ backscatter modulator. This receiver allows one to compensate for the effects of the backscatter channel and the detuning of the antenna. Using both this modulator and this receiver, any backscattered message can be exchanged between a tag and a reader at a fraction of the complexity and power of active transceivers.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"10 ","pages":"208-215"},"PeriodicalIF":3.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147558065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}