{"title":"Human Activity Recognition: A Review of RFID and Wearable Sensor Technologies Powered by AI","authors":"Ria Kanjilal;Muhammed Furkan Kucuk;Ismail Uysal","doi":"10.1109/JRFID.2025.3561345","DOIUrl":"https://doi.org/10.1109/JRFID.2025.3561345","url":null,"abstract":"Human activity recognition (HAR) has garnered significant attention across diverse domains such as fitness enhancement, safety, elderly care, clinical monitoring, and smart environments. However, despite its potential, HAR faces challenges like handling noisy and diverse data, ensuring real-time performance, maintaining user privacy, and achieving high accuracy across varying contexts and activities. A primary challenge of HAR lies in maintaining consistency and accuracy during data collection amidst varied activities and environments. This review article provides a comprehensive overview of the advancements in AI-enhanced HAR methods, with a focus on radio frequency identification system, wearable devices, and smartphone sensor technologies. We delve into the frameworks of these technologies, detailing processes like data collection, preprocessing, and the application of machine learning and deep learning algorithms. Additionally, we outline the advantages and drawbacks of these techniques and provide a brief comparison between them.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"9 ","pages":"180-199"},"PeriodicalIF":2.3,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143883365","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":"MU-MIMO for Passive UHF RFID","authors":"Ryan Jones;Shuai Yang;Richard Penty;Michael Crisp","doi":"10.1109/JRFID.2025.3561497","DOIUrl":"https://doi.org/10.1109/JRFID.2025.3561497","url":null,"abstract":"Radio Frequency Identification (RFID) is frequently deployed in high tag density environments, where tag read rate can become a limiting factor. Current Class 1 Gen 2 (C1G2) RFID systems are limited in read rate by the Framed Slotted Aloha (FSA) scheduling algorithm and physical layer modulation parameters. We propose a multi-user MIMO (MU-MIMO) RFID system compatible with C1G2 which enables simultaneous communication with multiple tags, achieving greater read rates. Multiple monostatic reader antennas are exploited to recover collided tag data and perform channel estimation. These channel estimates are then used to precode the reader’s ACK signals across multiple transmit antennas into spatial channels such that the tags will receive separated acknowledgements. To evaluate potential performance gains, we calculate theoretical throughput improvements and empirically measure the signal-to-interference ratio (SIR) required for commercial passive tags to respond to collided acknowledgements. Furthermore, we perform simulations to determine the effect of increasing number of tag responses on channel estimation accuracy, and hence the received SIR at tags. An experiment is carried out using two monostatic transceivers with two emulated tags, showing successful channel recoveries and uncollided reader acknowledgments commands at the tags, and hence compatability with C1G2 protocol provided a reader can be developed meeting the timing requirements.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"9 ","pages":"215-226"},"PeriodicalIF":2.3,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896542","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":"Compact Folded Dipolar Patch Antenna With Broad Tuning Range for On-Metal Tag Design","authors":"Subbiah Alagiasundaram;Kim-Yee Lee;Eng-Hock Lim;Pei-Song Chee","doi":"10.1109/JRFID.2025.3561277","DOIUrl":"https://doi.org/10.1109/JRFID.2025.3561277","url":null,"abstract":"A compact dipolar patch antenna, which is embedded with a middle-layer patch internally, is proposed for designing an on-metal tag. Multiple tuning mechanisms have been employed for enabling frequency tuning over a wide bandwidth. First, the antenna’s shorting stubs are displaced diagonally to two opposite corners for lengthening the current paths. Then, the two patches are coupled capacitively for generating additional tuning reactance. Finally, multiple inductive slits have been incorporated with the patches for lowering the tag’s resonant frequency. Employment of the tuning mechanisms has successfully brought the tag resonance down to the UHF RFID passband. Notably, adjusting the slit length <inline-formula> <tex-math>$(i_{2})$ </tex-math></inline-formula> allows the tag’s resonant frequency to be tuned across a broad range from 834 MHz to 964 MHz. Despite its compact size of <inline-formula> <tex-math>$25times 25times 3.3$ </tex-math></inline-formula> mm3, the proposed tag can be read from a distance of 16 m (with 4W EIRP), which is much longer than most of the contemporary on-metal tags of this size.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"9 ","pages":"170-179"},"PeriodicalIF":2.3,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143883334","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 High-Reliability PUF Solution for Securing RFID Systems Against Machine Learning","authors":"Abolfazl Rajaiyan;Yas Hosseini Tehrani;Seyed Mojtaba Atarodi","doi":"10.1109/JRFID.2025.3560996","DOIUrl":"https://doi.org/10.1109/JRFID.2025.3560996","url":null,"abstract":"For Radio Frequency Identification (RFID) security, reliable keys are essential. Physical Unclonable Functions (PUFs) prevent physical cloning, but they are sensitive to environmental variations and vulnerable to Machine Learning (ML) attacks. In this paper, a security system is proposed that aims to generate keys with high reliability and resistance to ML attacks. The entire system can be integrated into RFID tags. For reliable key generation, the proposed approach utilizes a two-step structure comprising a Coarse PUF and a Fine PUF, along with modified Ring Oscillator (RO) PUFs featuring varying ring counts. This design enhances resistance to machine learning (ML) attacks through challenge obfuscation. To further improve security against ML attacks, real-time power consumption is monitored using a novel analog circuit, and a hardware algorithm is developed based on the monitored power data. The proposed PUF (128-bit key generator) is implemented on an FPGA from the Xilinx family, specifically the Zynq-7 model. The robustness of the proposed PUF is evaluated through voltage and temperature variation tests. Experimental results demonstrate a Bit Error Rate (BER) of <inline-formula> <tex-math>$3.42times 10^{-5}$ </tex-math></inline-formula>, with uniqueness and uniformity values of 49.77% and 50.27%, respectively. While a conventional PUF exhibits a vulnerability of 91.23%, the implementation of the proposed system and hardware algorithm reduces this vulnerability to 50.17%. The obtained results confirm that the proposed system offers a significantly more secure and robust solution compared to other competitors.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"9 ","pages":"161-169"},"PeriodicalIF":2.3,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143875107","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}
Karl Adolphs-Saura;Ferran Paredes;Amirhossein Karami-Horestani;Pau Casacuberta;Paris Vélez;Ferran Martín
{"title":"Phase-Modulation All-Dielectric and “Green” Electromagnetic Encoders for Motion Sensing and Near-Field Chipless-RFID","authors":"Karl Adolphs-Saura;Ferran Paredes;Amirhossein Karami-Horestani;Pau Casacuberta;Paris Vélez;Ferran Martín","doi":"10.1109/JRFID.2025.3560736","DOIUrl":"https://doi.org/10.1109/JRFID.2025.3560736","url":null,"abstract":"In this paper, a new electromagnetic encoder system for motion sensing and near-field chipless-RFID applications is presented. The system consists of an encoder, based on chains of transversally oriented linear apertures in a dielectric substrate, and a reader with an open-ended quarter-wavelength resonator that is sensitive to the presence of the apertures. The reader can detect variations in the phase of the reflection coefficient due to the motion of the encoder. To validate the encoder system, two encoders are implemented in a low-loss rigid substrate, and four are fabricated in flexible substrates, such as paper and plastic (polyethylene terephthalate -PET). One of the rigid encoders is incremental (with a periodic chain of apertures) and the other one is quasi-absolute (with two aperture sizes), useful for both motion sensing and near-field chipless-RFID. For the encoders implemented in flexible substrates (quasi-absolute in all cases), the apertures are replaced with linear chains of small holes, with a period of <inline-formula> <tex-math>${p}{=}2$ </tex-math></inline-formula>.3 mm. The resulting density of bits per unit length is DPL <inline-formula> <tex-math>${=}4.35$ </tex-math></inline-formula> bit/cm. Such encoders provide a means to implement cost-effective and eco-friendly (“green”) systems.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"9 ","pages":"146-160"},"PeriodicalIF":2.3,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143875272","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":"Innovations in RFID and Wireless-IoT: Advancements in Smart Technologies and Sensing Applications Guest Editorial of the Special Issue on SpliTech 2024 Conference","authors":"Luca Catarinucci;Andrea Ria;Arnaud Vena","doi":"10.1109/JRFID.2025.3553925","DOIUrl":"https://doi.org/10.1109/JRFID.2025.3553925","url":null,"abstract":"","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"9 ","pages":"123-125"},"PeriodicalIF":2.3,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10949084","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Differential RCS of Multi-Port Tag Antenna With Synchronous Modulated Backscatter","authors":"Nicolas Barbot;Ionela Prodan;Pavel Nikitin","doi":"10.1109/JRFID.2025.3557078","DOIUrl":"https://doi.org/10.1109/JRFID.2025.3557078","url":null,"abstract":"This paper introduces a new method, called multi-port load modulation, allowing one to improve the delta RCS of any passive transponder. By switching simultaneously the loads connected to a multi-port antenna, we show that the associated delta RCS can be higher than the one predicted by the equations of R. Green in 1963. We demonstrate analytically that the delta RCS of the multi-port tag can be improved by 6 dB compared to a single port antenna. This improvement corresponds to an increase of the round-trip read range of 41%. This result can still be improved if the modulation of the structural mode adds constructively with the modulation of the antenna mode. Simulation and measurement of a fully compliant dual-port tag validate the model and achieve a large part of the predicted improvement.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"9 ","pages":"126-134"},"PeriodicalIF":2.3,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143817831","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":"Adaptive Millimeter Wave Channel Switching Based on Real-Time Weather Data Using Fuzzy Logic Control","authors":"Abdulmajid Mrebit;Esmail Abuhdima;Jian Liu;Amirhossein Nazeri;Nabeyou Tadessa;Naomi Rolle;Jason Laing;Gurcan Comert;Chin-Tser Huang;Pierluigi Pisu","doi":"10.1109/JRFID.2025.3575098","DOIUrl":"https://doi.org/10.1109/JRFID.2025.3575098","url":null,"abstract":"Millimeter wave (mmWave) communication systems offer high data rates, but these systems are highly susceptible to environmental factors, particularly weather conditions such as rain, dust, and sand. This paper presents a novel approach to enhance the reliability of mmWave communication by implementing a Fuzzy Controller System (FCS) for dynamic channel switching. The proposed system integrates real-time measured weather data, such as rain rate, with the fuzzy logic controller to intelligently select the optimum frequency channel with the least attenuation under current atmospheric conditions. The fuzzy controller makes adaptive switching decisions by continuously analyzing environmental changes to maintain signal quality and system performance. Experimental results and simulations demonstrate that incorporating real measured data significantly improves the system’s ability to respond to weather variability, ensuring stable and efficient mmWave communication. This work provides a practical framework for implementing intelligent, weather-aware channel-switching mechanisms in next-generation wireless communication networks.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"9 ","pages":"377-383"},"PeriodicalIF":2.3,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144502876","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":"Power Efficient and Long Range Precision Agriculture Monitoring System","authors":"Radhika Raina;Kamal Jeet Singh;Suman Kumar","doi":"10.1109/JRFID.2025.3574759","DOIUrl":"https://doi.org/10.1109/JRFID.2025.3574759","url":null,"abstract":"Precision agriculture, also referred to as precision farming or smart farming, uses technology to improve the efficiency, sustainability and productivity of agricultural practices. Traditional precision agriculture systems often suffer from limited communication range and high power consumption, which restrict their scalability and long term deployment in large scale farms. Furthermore, existing literature lacks integrated solutions that address both range extension and power minimization in precision agriculture monitoring. To bridge this gap, multiple power efficient soil moisture monitoring nodes are deployed in the farm which transmit data using Bluetooth Low Energy (BLE) technology. Also, this paper investigates the power consumption of the entire precision agriculture monitoring system, including both the sensor nodes and the gateway, which has not been addressed in the previous research works. Soil moisture node has a battery lifetime of 114.18 hrs with 620 mAh / 3V battery. The soil moisture data is received by the gateway (receiver) which then sends data to the cloud. Also, Low Noise Amplifier (LNA) is used at the receiver which reduces the packet loss and increases the range of soil moisture monitoring nodes. Additionally, light intensity (VCNL4040), anemometer, temperature and humidity (SHT40) sensors are interfaced with the gateway which sends data to the cloud directly using Global System for Mobile Communication (GSM) technology. Therefore, this paper proposes novel and power-efficient agricultural monitoring device that also acts as a gateway has a battery life of 106.74 hrs with 15600 mAh / 4.2 V battery. Additionally, the mean absolute errors calculated for the soil moisture sensor (ZSSC3123), VCNL4040, SHT40 and anemometer using reference sensors are 0.1, 1.9, 1.33 and 1.42 respectively.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"9 ","pages":"330-339"},"PeriodicalIF":2.3,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144299381","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}
Rahul Bhattacharyya;Fatima Villa Gonzalez;Pavel Nikitin
{"title":"Material Sensing Using RAIN RFID Tags With Auto-Tuning Capabilities","authors":"Rahul Bhattacharyya;Fatima Villa Gonzalez;Pavel Nikitin","doi":"10.1109/JRFID.2025.3575043","DOIUrl":"https://doi.org/10.1109/JRFID.2025.3575043","url":null,"abstract":"In this paper, we demonstrate how the power-on-tag-forward (POTF) and reverse (POTR) resonance frequencies can be estimated simply by measuring changes in the autotune (AT) code of RAIN RFID chips capable of making capacitance adjustments for enhanced antenna impedance matching. We show how this approach allows us to reliably estimate these characteristic frequencies — and, by extension, the dielectric and magnetic properties — of objects using a simple reading of the AT state values in the chip memory. Therefore, we eliminate the need for full POTF and/or POTR curve measurement and the need for read distance estimation and environmental calibration. The proposed method shows repeatability using 6 diverse RAIN RFID tags with T-matched antenna designs and self-tuning ICs, deployed on 7 dielectrics and 1 magnetic material. Current limitations and future research directions are also discussed.","PeriodicalId":73291,"journal":{"name":"IEEE journal of radio frequency identification","volume":"9 ","pages":"340-349"},"PeriodicalIF":2.3,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144323046","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}