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关键词： Electric bike   Passive smart-tag   Power harvester   Pressure monitoring system   Radio frequency identification   Rectenna  

摘要： Thanks to the miniaturization of components and therefore the significant reduction of energy needs, the design of passive smart-tag incorporating intelligent sensors is now possible. The goal of this study is to develop a tire pressure sensor for an electric bike with battery-free. Therefore, there is no need to replace periodically the battery, so as cuts off maintenance costs and extend the life time of the smart-tags. An UHF RFID reader installed on the bicycle frame and connected to the battery e-bike transmits the RF power at 868 MHz toward each tag integrated in the wheel rims. Firstly, this article presents the whole hardware architecture of a passive smart-tag which had to respond of technics constraints and the complexity to integrate 2 antennas in a small package box. Secondly, the methods to ensure an ultra-low consumption are developed. Finally, practical tests are compared with simulations, and, validations are carried out showing the compliance and the industrialization of this innovative system. © 2022 The Authors

关键词： Radiofrequency identification   Directive antennas   Antennas   Estimation   Frequency measurement   Antenna measurements   Bandwidth   Direction of arrival (DOA)   leaky-wave antenna (LWA)   monopulse antenna   passive RFID   UHF  

摘要： A compact printed-circuit leaky-wave antenna is designed to synthesize frequency-scanned monopulse patterns in the UHF RFID band from 902 to 928 MHz. A high-permittivity ceramic substrate is used to maximize the angular scanning range in such a narrow band. Two operating modes, i.e., narrow-field and wide-field modes, can be chosen by properly selecting the frequency channels and antenna ports. This allows to adapt to different fields of view while maximizing the maximum reading distance, as demonstrated with a fabricated prototype.

关键词： Cloning   Radiofrequency identification   Probabilistic logic   Protocols   Reliability   Physical unclonable function   Informatics   Anonymous radio frequency identification (RFID) systems   attack probability   detection reliability   probabilistic cloning attack  

摘要： Radio frequency identification (RFID) systems have achieved wide applications in various scenarios, such as warehouse management, logistic tracking, smart transportation, etc. Despite the enormous benefits from the RFID systems, the security issues are still of great concern, such as the cloning attacks. In this article, we focus on the detection of probabilistic cloning attacks for the anonymous RFID systems, in which each cloned genuine tag suffers attacks from its clone tags with a certain probability. We propose an efficient detection protocol against the probabilistic cloning attacks in anonymous RFID systems named DAP, which can detect the probabilistic cloning attacks with the required detection reliability alpha if at least one tag is attacked with the probability no less than the threshold P-T. The proposed DAP protocol fully utilizes the inconsistency and unreconcilable collision caused by the probabilistic cloning attacks to effectively detect the probabilistic cloning *** parameters are theoretically analyzed to maximize the detection efficiency. The extensive simulations are conducted and the results demonstrate the effectiveness of the proposed DAP protocol.

关键词： speed   RFID   inventory   drones   labor   forecast  

摘要： Accurate inventory allows for more precise forecasting, including profit projections, easier monitoring, shorter outages, and fewer delivery interruptions. Moreover, the long hours of physical labor involved over such a broad area and the effect of inefficiencies could lead to less accurate inventory. Unreliable data and predictions, unannounced stoppages in operations, production delays and delivery, and a considerable loss of profit can all arise from inaccurate inventory. This paper extends our previous work with drones and RFID by evaluating: the number of flights needed to read all tags deployed in the field, the number of scans per pass, and the optimum drone speed for reading tags. The drone flight plan was divided into eight passes from southwest to northwest and back at a horizontal speed of 2.2, 1.7, and 1.1 m per second (m/s) at a vertically fixed altitude. The results showed that speed did not affect the number of new tags scanned (p-value > 0.05). Results showed that 90% of the tags were scanned in less than four trips (eight passes) at 1.7 m/s. Based on these results, the system can be used for large-scale nursery inventory and other industries that use RFID tags in outdoor environments. We presented two novel measurements on evaluating RFID reader efficiency by measuring how fast the reader can read and the shortest distance traveled by the RFID reader over tag.

关键词： circularly polarization   tri-band antenna   RFID portable reader   UHF   MW-RFID reader antenna  

摘要： A compact three-port tri-band circularly polarized (CP) antenna for radio-frequency identification (RFID) technique is introduced. Four inverted-F radiating elements fed with a 90 degrees phase delay feeding network realize the CP radiation at the FCC UHF-RFID band (0.902-0.928 GHz). With the slot-coupled feeding technique, Corner-truncated slot and patch have been employed to achieve CP radiation at MW-RFID bands (2.4-2.485/5.725-5.875 GHz). Decoupling structures are implemented to obtain excellent 20 dB port isolations during all operating bands. The relative impedance bandwidths in the three bands are 6.6%, 5.3%, and 5.1%, respectively, with peak gains of 2, 5.1, and 5.7 dBic.

关键词： ultra high-frequency   radio frequency identification   dynamic measurement   salt mist   conduc-tivity   concentration control reading distance  

摘要： Aiming at the problem that salt mist seriously affects the reading performance of radio frequency identification (R FID) tags, the salt mist effects on the performance of RFID tags are researched through simulation and measurement. The reading range of RFID tags in the salt mist environment is reduced because the boundary conditions of the test chamber reduce the antenna efficiency and gain. As the concentration of the salt mist in the test chamber increases, the environmental conductivity in the test chamber increases, and the RFID reading distance of the tag decreases. In this paper, a theoretical formula is proposed for calculating RFID reading distance in salt mist environment. Besides, RFID dynamic identification based on the salt mist environment platform is designed. Corresponding functions are obtained by fitting the experimental data. This function establishes the relationship between salt mist concentration and the RFID reading distance. The experiment shows this theoretical formula is feasible, and the system has high practicability. At the same time, the system shows that the reading distance decreases as long as the concentration of the salt mist increases.

关键词： chipless RFID   Arabic alphabets   printable RFID   cheap RFID   paper-based RFID   radar cross-section (RCS)   font type   font size  

摘要： This work presents the design and analysis of newly developed reconfigurable, flexible, inexpensive, optically-controlled, and fully printable chipless Arabic alphabet-based radio frequency identification (RFID) tags. The etching of the metallic copper tag strip is performed on a flexible simple thin paper substrate (epsilon(r) = 2.31) backed by a metallic ground plane. The analysis of investigated tags is performed in CST MWS in the frequency range of 1-12 GHz for the determination of the unique signature resonance characteristics of each tag in terms of its back-scattered horizontal and vertical mono-static radar cross section (RCS). The analysis reflects that each tag has its own unique electromagnetic signature (EMS) due to the changing current distribution of metallic resonator. This EMS of each tag could be used for the robust detection and recognition of all realized 28 Arabic alphabet tags. The study also discusses, for the first time, the effect of the change in font type and size of realized tags on their EMS. The robustness and reliability of the obtained EMS of letter tags is confirmed by comparing the RCS results for selective letter tags using FDTD and MoM numerical methods, which shows very good agreement. The proposed tags could be used for smart internet of things (IoT) and product marketing applications.

关键词： Indoor localization   Transceiver separation system   Received signal strength   Three-point localization method  

摘要： The indoor localization problem is considered for the transceiver separation radio frequency identification (RFID) system suffering from random noises and multipath interference. An RSS difference method is presented to preprocess the measured RSS to reduce the complexity of system modeling. Then, an improved three-point localization algorithm is designed to estimate the target location. Specifically, two solutions based on 2-norm and non-convex optimization are respectively proposed to weaken the influence of the noises and multipath on positioning performance. The simulation results show that the proposed method can significantly improve the localization accuracy and provide satisfactory robustness in different indoor environments.

关键词： Analytical models   Time-frequency analysis   Linear systems   Scattering   Resonant frequency   Radiofrequency identification   Predictive models   Chipless radio frequency identification (RFID)   Doppler effect   radar cross section (RCS)   read range   scatterers  

摘要： This article demonstrates how motion effect can be exploited to read moving chipless radio frequency identification (RFID) tags at larger distances compared to what has been reached without taking into account the movement. According to the Doppler effect, due to the time-variant behavior of moving chipless tags, the tag backscattered field contains frequency components different from those that are transmitted. These motion-induced frequency components can be utilized to efficiently detect the tag at large distances, in a real environment composed of stationary objects. A circuit-based analytical model verified by full-wave simulations is presented to effectively predict the quasi-stationary backscattered field from moving scatterers, with fast computation process. The developed analytic model is applied to rotating dipole scatterers and is used to design chipless tags, including an identifier. In terms of identification, good agreement is observed between the measurement results and those are predicted by the model. Finally, read range enhancement is proven experimentally by a real environment measurement where the chipless tags are readable at distances up to several meters.

关键词： Probabilistic loss assessment   Rapid loss assessment   Near-real-time loss assessment   Performance-based earthquake engineering   Structural deformation condition   RFID  

摘要： A rapid probabilistic seismic loss (e.g., repair time and repair cost) assessment methodology for building structures is developed based on radio frequency identification (RFID) based wireless deformation sensors. The sensors can detect whether the multiple preset tensile deformation thresholds of structural components are exceeded, and the structural deformation data are recorded in RFID tags. Then, the RIFD tags are scanned and the deformations are collected by an RFID interrogator, carried into the damaged building after earthquakes, without requirement of removals of coverings such as drywall. The sensors provide valuable deformation information that can be utilized to estimate the probability distributions of repair time (RT) and repair cost (RC) of the building. In this paper, a seismic loss assessment methodology that combines the FEMA P-58 fragility database with Bayes' theorem is proposed to exploit the information provided by the RFID sensors. The assessment is rapid because dynamic response analysis is not required in the post-earthquake phase. The feasibility of the technique is examined using a tension only concentrically braced steel beam-through frame. The accuracy of the technique is tested by an alternative method. The uncertainties for seismic loss assessment are significantly reduced owing to the available deformation condition information.