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关键词： 射频识别读写器   天线阵列   小鼠定位跟踪  

摘要： 常见的定位技术用于笼内小鼠跟踪准确度不高。为提高笼内小鼠定位准确性,提出了一种基于射频识别(RFID)技术的笼内小鼠定位跟踪和行为分析系统,通过放置在饲养笼下方的RFID读写器天线阵列板实现定位跟踪,上位机软件可实时显示小鼠的活动轨迹图以便科研人员对小鼠进行行为分析。通过模拟实验和生物实验,该系统可准确定位4×6阵列中小鼠位置,定位准确率可达95%以上,其中,组成阵列的单元格尺寸仅为45 mm×45 mm。

关键词： 长短期记忆神经网络   射频识别   感知识别   时间序列   固定资产实时监测  

摘要： 针对传统基于射频识别的固定资产感知方法存在射频信号易受环境影响、多个标签互干扰、感知识别精度低等问题,提出一种基于射频识别(RFID)和长短期记忆神经网络(LSTM)的固定资产状态智能感知方法。为克服RFID信号接收时间非连续性导致的识别精度低问题,引入序列分析思想,使用LSTM对一段时间内接收到的RFID信号序列进行模式学习,构建基于RFID和LSTM的固定资产感知模型,实现固定资产位置的二分类辨识。所提方法在高校实验室条件下开展实测实验进行性能验证。结果表明,使用序列分析的固定资产状态感知模型辨识准确率可达99.26%,比传统基于离散时刻点的RFID感知模型辨识准确率高11.05%,且对多标签的识别准确率可达93.0%。

关键词： RFID   无线传感技术   呼吸监测   纺织基传感器   可穿戴  

摘要： 射频识别(Radio Frequency Identification,RFID)传感技术可实现多个用户的同时低功耗无线呼吸监测,在可穿戴智慧医疗健康领域倍受关注。在概述各种呼吸监测技术基础上,重点回顾了采用柔性RFID传感技术,特别是纺织基柔性传感器监测呼吸的基本原理和相关研究现状,比较分析了不同RFID传感方法用于呼吸监测的优缺点,最后提出了在呼吸监测领域应用纺织基RFID传感技术时面临的主要挑战和研究方向。

关键词： Antenna measurements   Protocols   Phantoms   Modulation   Wearable antennas   Transponders   RFID tags   Backscatter   Wireless networks   Decoding  

摘要： The interest in wearable antenna design has increased significantly due to its potential applications for humans, especially in the context of RF identification (RFID) technology. RFID transponders can wirelessly transmit identification numbers or sensor data over short distances. RFID systems comprise essential components, including a reader or interrogator, an RFID tag or transponder (receive and respond), as well as a comprehensive set of coding and decoding protocols [1], [2].

关键词： Angle of incidence   chipless RFID   coding den   fractal tags   RFID readers  

摘要： - The role of the orientation of the radio frequency identification (RFID) reader is vital in the RFIDbased communication system. This study presents the design and analysis of the impact of the orientation of the RFID reader (angle of incidence of the plane wave) on the detection and sensitivity characteristics of fractal chipless RFID tags. Four fractal (irregular) shaped tags are developed using four iterations of the Hilbert curve filling algorithm. The full-wave EM analysis of the designed tags in Matlab is performed by exporting them in Computer Simulation Technologies Micro-Wave Studio (CST MWS) in the frequency range of 2 to 20 GHz. Firstly, the performance of the tags is analyzed by observing the radar cross-section (RCS) of the tag for the fixed orientation of the incident plane wave in three different polarizations (horizontal, vertical, and oblique). Later, the variations in the EM spectrum (RCS results) are analyzed for oblique polarization by varying the incidence plane wave in both elevations (for two cases of 0 degrees and 90 degrees) and azimuth planes (sweeping from 0 degrees to 180 degrees with a step size of 10 degrees). The analysis of the proposed aggregated RCS response for all cases in oblique polarization produces higher coding capacity (169 bits), coding spatial capacity (16.504 bits/cm2), coding spectral capacity (9.826 bits/GHz), and coding density (0.960 bits/GHz/cm2) for the realized highly irregular tag using fourth-iteration (4T) of Hilbert curve filling algorithm. The proposed procedure of detection based on aggregated response makes the developed RFID communication system more secure and reliable.

关键词： Polydimethylsiloxane  

摘要： This study presents a bilayer polydimethylsiloxane (PDMS) composite microwave absorber, consisting of Fe2O3 and polytetrafluoroethylene (PTFE) fillers, to enhance the functioning of radio frequency identification (RFID) systems on conductive surfaces. The uniform Fe2O3/PDMS and PTFE/PDMS composites are prepared by mixing PDMS and respective filler through a desktop three-axis roller machine followed by curing at 80 °C for two hours. The composites are then joined to create a bilayer composite mat. The combination of a 70 wt% Fe2O3/PDMS composite with a 50 wt% PTFE/PDMS composite demonstrates the best performance. The Fe2O3/PDMS composite shows the high reflection loss of 47.98 dB and a total shielding of 4.1 dB, while the PTFE/PDMS composite exhibits the reflection loss of 47.0 dB and a total shielding of 0.6 dB. The optimized bilayer composite enables a tag recovery of approximately 87.57 %. These findings demonstrate its practical application in reducing interference and enhancing the RFID tag detection. © 2024 Elsevier Ltd

关键词： RFID   UHF   capacity measurement   capacitive sensors   active identifier   semi-passive identifier   textronic   textronic sensors   textronic RFID identifier  

摘要： This article presents an innovative combination of textile electrical circuits with advanced capabilities of electronic RFID sensors, indicating the revolutionary nature of the development of textronics, which is used in various areas of life, from fashion to medicine. A review of the literature relating to the construction of textronic RFID identifiers and capacitive textronic sensors is performed. Various approaches to measuring capacity using RFID tags are discussed. This article focuses on presenting the concept of a capacitive sensor with an RFID interface, consisting of a microelectronic part and a textile part. The textile part is based on the WL4007 material, where antennas and capacitive sensors are embroidered using SPARKFUN DEV 11791 conductive thread. The antenna is a half-wave dipole designed to operate at a frequency of 860 MHZ. The microelectronic part is sewn to the textile part and consists of a microcontroller, an RFID-integrated circuit and a coupling loop, placed on the PCB. The embroidered antenna is coupled with a loop on the microelectronic module. This article focuses on presenting various designs of textronic electrodes, enabling various types of measurements. Article presents capacitance measurements of individual sensor electrodes, made using a measuring bridge and a built RFID tag. The sensors' capacity measurement results are shown.

关键词： Apis mellifera   bee orientation   crop pollination   protected cropping   RFID   sweet cherry  

摘要： Advancements in agricultural production have seen the rapid adoption of protected cropping systems globally. Such systems have been optimized for plant growth and efficiency, with little understanding of the potential impacts to key insect pollinators. Here, we investigate the effect of bird netting and polythene rain covers on the health and performance of honey bees (Apis mellifera L.) during the pollination of sweet cherry crops. Over two consecutive seasons, 12 full-strength colonies were equipped with tagged bees and radio frequency identification (RFID) systems. The colonies were equally divided between open control, bird netted and polythene (semi-permanent VOEN in 2019 and retractable Cravo in 2020) groups. Over 1300 individual bees were monitored for the duration of the commercial pollination period to determine behavioural parameters such as foraging commencement age, number and duration of trips and overall survival. Bees began foraging within the optimum age range (mean 15.7-24.1 days) under all covering types, with little indication of prolonged stress or increased mortality during the short season. Polythene covers (VOEN & Cravo) were found to significantly increase the total time needed for bees to orientate successfully. Once orientated, bees placed under covers conducted up to 155% more foraging trips, with a longer cumulative duration. Covering type was found to significantly impact the amount and type of pollen collected, with the most restrictive system (VOEN) yielding the highest proportion of cherry pollen. Overall, we found little evidence to suggest that the tested protective covers have a detrimental impact to honey bee foraging in cherry crops.

关键词： Robots   Location awareness   Radiofrequency identification   Hidden Markov models   Real-time systems   Trajectory   Service robots   RFID   real-time tracking   high speed  

摘要： This paper presents GLAC, the first 3D localization system that enables millimeter-level object manipulation for robotics using only COTS RFID devices. The key insight of GLAC is that mobility reduces ambiguity (One-to-many mapping relationship between phase and distance) and thus improves accuracy. Unlike state-of-the-art systems that require extra time or hardware to boost performance, it draws the power of modeling mobility in a delicate way. In particular, we build a novel framework for real-time tracking using the Hidden Markov Model (HMM). In our framework, multiple Kalman filters are designed to take a single phase observation for updating mobility states, and a fast inference algorithm is proposed to efficiently process an exponentially large number of candidate trajectories. We prototype GLAC with only UHF tags and a commercial reader of four antennas. Comprehensive experiments show that the median position accuracies of x/y/z dimensions are within 1 cm for both LoS and NLoS cases. The median position accuracy for slow-moving targets is 0.41 cm, which is 2.2 x, 17.3 x , and 14.9 x better than TurboTrack, Tagoram, and RF-IDraw, respectively. Also, its median velocity accuracy is at least 20 x better than all three competitors for fast-moving targets. Besides accuracy, it achieves more than 4 x localization time gains over state-of-the-art systems.

关键词： Collision Arbitration   Internet of Things   RFID   Q-Algorithm  

摘要： In the realm of large-scale identification deployments, the EPCglobal Class -1 Generation -2 (Gen2) standard serves as a cornerstone, facilitating rapid processing of numerous passive RFID tags. The Q-Algorithm has garnered considerable attention for its potential to markedly enhance the efficiency of Gen2-based RFID systems with minimal adjustments. This paper introduces a groundbreaking iteration of the Q-Algorithm, termed Time-Efficient Q-Algorithm (SwiftQ), specifically designed to push the boundaries of time efficiency within Gen2-based RFID systems. Through exhaustive simulations, our study substantiates that SwiftQ outperforms existing algorithms by a significant margin, demonstrating exceptional expediency that positions it as a formidable contender in the landscape of large-scale identification environments. By prioritizing time efficiency, SwiftQ offers a promising solution to meet the escalating demands of contemporary Internet of Things applications, underscoring its potential to catalyze advancements in RFID technology for diverse industrial and logistical contexts.