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关键词： OFDM   Backscatter   Symbols   Receivers   Synchronization   Energy harvesting   Switches   Backscatter radio   RFID   sensor networks  

摘要： Backscatter radio only requires a simple switch, terminating the tag antenna between (at least) two loads. However, recent detection in ambient backscatter sensor networks assumes that the tag is receiver-equipped, able to synchronize its backscattering with the illuminating (ambient) transmission. Additional challenges with simple, potentially receiver-less, backscattering tags include: lack of cooperation with the legacy, ambient illuminator, asynchronous channel estimation, tag frame synchronization, energy harvesting for batteryless tag operation and multiple access. Part I addresses asynchronous channel estimation and detection with digital ambient signals and concrete analysis;Part II partially addresses all challenges with analog ambient signals and practical deployment.

关键词： holography   holographic label   RFID antenna   security label   UHF RFID   multilayer smart security labels  

摘要： Counterfeiting presents a major economic problem and an important risk for the public health and safety of individuals and countries. To make the counterfeiting process more difficult, and to ensure efficient authentication, a solution would be to attach anti-counterfeit labels that include a radio frequency identification (RFID) element to the products. This can allow real-time quality check along the entire supply chain. In this paper we present the technology optimized to obtain a multilayer holographic label with a high degree of security, patterned on a thin zinc sulfide film of a semi-transparent holographic foil rather than on the standard substrate for diffractive optical elements (metallized foil). The label is applied onto the product surface or packaging for anti-counterfeit protection. The developed multilayer structure contains various elements such as: a holographic background, nanotext-type elements, holographic elements, and an RFID antenna. The employed semi-transparent holographic foil offers the RFID antenna the possibility to transmit the electromagnetic signal through the label and thus to maximize the antenna footprint, achieving up to 10 m reading distance, with a 6 cm x 6 cm label, much smaller than the commercial standard (minimum 10 cm x 10 cm).

关键词： Smart logistics   Authentication   Object tracking   RFID   Internet of things  

摘要： Smart logistics play a crucial role for rapid industrialization and economic development of the countries. It not only assists in delivering the low cost services to the subscribers but also helps in bringing transparency in the supply chain management system with the creation of interactive ecosystem encompassing IoT, RFID and sensor-based objects. The realization of the concept of smart logistics includes the real-time communication and object tracking through 5G-oriented Internet of Things (IoT) and Information Communication Technology (ICT)-based smart devices. However, only technological advances are not enough until all intermediaries in the process of supply chain are reliable. Besides, the smart devices exchanging data are deficient in power and require energy friendly communication protocols. This requires the underlying protocols responsible for authenticating the entities in supply chain, to be secure as well as efficient. Recently, a few lightweight authentication protocols for object tracking and logistics including Anandhi et al. (https://***/10.1007/s11277-018-6033-6) have been presented. We ascertain that these schemes lack mutual authenticity and resistance to other forgery attacks. Considering the limitations in Anandhi et al. and other recently presented logistics and supply chain-based authenticated key agreements, we propose a new 5G enabled secure RFID authentication scheme for smart logistics. We analyze and validate the contributed model using formal security analysis based on random oracle model. The proposed scheme supports 19% more security features in comparison with other contemporary schemes. The performance evaluation results demonstrate promising findings for this scheme as compared to other studies.

关键词： circularly polarized   endfire   folded dipoles   quasi-Yagi   RFID  

摘要： A novel low-profile circularly polarized (CP) quasi-Yagi antenna with a wide 3-dB axial ratio (AR) bandwidth is proposed, which generates the endfire beam by combining magnetic microstrip cavity and folded electric dipoles with a 90ffi phase difference. The proposed antenna includes two shorting pins, which are employed to attain wider impedance bandwidth. Then, a phase delay line is added to connects two pairs of folded dipoles and a magnetic microstrip cavity to realize righthanded circularly polarized (RHCP). After optimization, a prototype with an overall size of 1:17 Chi 0:91 Chi 0:0387 lambda(3)(0) is designed. Simulated results demonstrate that the final model has 18:1% (5.01-6.01 GHz) 3dB AR bandwidth and 10 dB impedance bandwidth of 5:2%(5:67 5:97 GHz), respectively. In addition, experimental results demonstrate that the designed antenna is very applicable to the RFID system.

关键词： Industry 4   0   Smart manufacturing   RFID   Intelligent manufacturing systems   Digitalisation   Footwear industry   Industrial integration   Industrial informatisation  

摘要： In line with the emerging Industry 4.0 technologies and their challenges for implementation, this study presents the results of research that developed a novel industrial integrated information system based on open source and low-cost technologies. The proposed Control System via RFID for Online Monitoring and Optimisation of Production Lines uses hardware and software to analyse the production system flow and performance. A longitudinal in-depth case study in a manufacturing plant exposes the empirical challenges to developing and implementing intelligent manufacturing systems towards Industry 4.0 in practice. Findings demonstrated that the proposed system enables industrial information integration through supervision and generation of information from the shoop-floor contributing to the managerial decision-making process in real-time. Implications for practitioners and academics address some of the current challenges for implementing Industry 4.0 technologies and industrial information integration. This study extends the knowledge of industrial integration and RFID implementation within Industry 4.0 by presenting a real-life application based on open source and low-cost technologies. The insights and lessons gained in this study can potentially be generalised for future efforts across industry manufacturers with similar shop-floor.

关键词： RFIDtex systems   textronic transponder   identification efficiency   dynamic RFID systems   anticollision protocol  

摘要： The study on the numerical model of communication processes implemented in RFID systems, in which textile electronic (RFIDtex) tags are used, is presented in the paper. The efficiency analysis covers the case of dynamic identification of a large amount of RFIDtex tags that are located in a spatial interrogation zone of a typical Internet of Textile Things (IoTT) application. Simulations carried out in order to verify the efficiency of the identification process are confirmed by measurements on the dedicated laboratory stand. Since the application of the experiment is located in the area of a maintenance-free store to detect and distinguish textile products, particular attention is paid to reconstruction of conditions and object arrangements that are typical for this type of space. The model and experiment are developed on the basis of RFIDtex transponders that are restricted under the patent claim PL231291. The obtained results prove that within the scope of the assumed number of RFIDtex transponders, the user has great freedom in choosing the parameters of the communication protocol.

关键词： Inventory Inaccuracy   Counting   RFID   Simulation   Transaction Errors  

摘要： Inventory management decisions are one of the essential factors influencing the profitability of each supply chain member. However, in the real world and due to errors, the physical inventory and the inventory on the information system are frequently not matched, impacting the decision-making regarding inventory control. As a result, managers are constantly looking for ways to eliminate or reduce inventory errors. This study examines a retailer's inventory control problem with transaction errors over time. For this purpose, a single-item multiperiod model that adheres to a periodic review policy will be used. Therefore, the impact of two solutions, inventory counting and using RFID technology, on eliminating or reducing errors is assessed. In the section on inventory counting, unlike most papers that consider a counting cycle for inventory, it will be determined at the end of which period the inventory counting should be performed by acquiring the profit functions and their parameters. Also, when using RFID technology, it may occasionally fail to track the products, so the profit function is acquired with this error rate in mind. Moreover, it is determined when the inventory on the information system should be reset to eliminate errors accumulated over time. Furthermore, because these solutions each have costs, the discrete-event simulation approach calculates their profitability. Also, the profit changing of these solutions will be analyzed about various parameters.

关键词： RFID   IoT   machine learning   tag direction   outlier detection   data balancing  

摘要： In recent years, radio frequency identification (RFID) technology has been utilized to monitor product movements within a supply chain in real time. By utilizing RFID technology, the products can be tracked automatically in real-time. However, the RFID cannot detect the movement and direction of the tag. This study investigates the performance of machine learning (ML) algorithms to detect the movement and direction of passive RFID tags. The dataset utilized in this study was created by considering a variety of conceivable tag motions and directions that may occur in actual warehouse settings, such as going inside and out of the gate, moving close to the gate, turning around, and static tags. The statistical features are derived from the received signal strength (RSS) and the timestamp of tags. Our proposed model combined Isolation Forest (iForest) outlier detection, Synthetic Minority Over Sampling Technique (SMOTE) and Random Forest (RF) has shown the highest accuracy up to 94.251% as compared to other ML models in detecting the movement and direction of RFID tags. In addition, we demonstrated the proposed classification model could be applied to a web-based monitoring system, so that tagged products that move in or out through a gate can be correctly identified. This study is expected to improve the RFID gate on detecting the status of products (being received or delivered) automatically.

关键词： Radio-frequency identification (RFID)   RFID network planning   Evolutionary algorithm   RFID receiving gate   Automotive industry   Logistics  

摘要： Radio frequency identification (RFID) is a widespread technology used in several different industries. One of its common use cases in logistics is the automation of goods receipt. RFID gates are often deployed, to automatically detect tagged items or load carriers during their passage through the goods receipt gate. At present, however, the design of RFID gates is often based on estimations, and their commissioning is mostly approached via trial and error. Even if the RFID network planning problem is known in the literature, existing algorithms cannot be applied to the design of RFID gates due to some limitations. In this paper, we propose a new evolutionary RFID network planning algorithm to design RFID gates optimally. The objective of our algorithm is to minimise the number of antennas and to adjust their mounting heights and angles. The algorithm ensures a tag coverage of at least 99%, prevents reflections on the ground, and can be used in the future as a standard for planning and commissioning RFID-enabled goods receipt gates. To demonstrate the applicability of our algorithm, we deployed it in a case study involving logistics of the automotive sector. The results of the deployment confirm the quality of our approach, as the RFID gate optimised by the algorithm deployed 4 antennas, with a vertical coverage rate of 99.96%, an horizontal coverage rate of 89.66%, and very interesting values of other evaluation functions, namely load balance and overlapping rate.

关键词： Feature extraction   Radiofrequency identification   Object recognition   Monitoring   Data preprocessing   Data mining   Antennas   Convolutional neural network (CNN)   feature extraction   object identification   radio frequency identification (RFID)  

摘要： In this article, we design and implement RF-Ray, a system that can detect whether the internal object of a package is illegally replaced using radio frequency (RF) identification tags in dynamic transport without opening the package, preventing the replacement of objects and enhancing the safety of the object in transport. RF-Ray is based on the principle that different objects have different reflective features to tag signals, and we extract the reflective features of the object from multipath signals by building a feature extraction model, which is based on a convolutional neural network. We propose solutions to all challenges encountered and conduct extensive experiments to verify system's accuracy. Our results show that RF-Ray can achieve an accuracy rate of over 97%. Compared with Echoscope, TagRay, and Tagscan, RF-Ray can guarantee high accuracy to identify the internal object in the package in dynamic scenes. In addition, we conduct an experimental analysis of factors that affect the performance of the system, and experiments demonstrate that RF-Ray has a good performance.