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关键词： Tangible interaction   Touch interaction   Tabletop   Dual reality   Crisis management   Robots  

摘要： Robots are becoming more and more present in many domains of our daily lives. Their usage encompasses industry, home automation, space exploration, and military operations. Robots can also be used in crisis management situations, where it is impossible to access or dangerous to send humans into the intervention area. The present work compares users' performances on tangible and on touch user interfaces, for a crisis management application on tabletop. The studied task consists of remotely controlling robots in a simulated disaster/intervention area using a tabletop equipped with a layer of RFID antennas, by displacing mini-robots on its surface matching the situation of the real robots on the ground. Dual reality enforces an accurate and up-to-date mapping between the real robots and the mini robots on the tabletop surface. Our findings show that tangible interaction outperforms touch interaction in effectiveness, efficiency and usability, in a task of remote control of one and two robots;only when the user manipulates a single robot remains the efficiency dimension unchanged between tangible and touch interaction. Results also show that tangible interaction technique does not significantly lower the users' workload. We finally expose a post-experiment interview and questionnaire results, assessing the participants' overall satisfaction and agreement on using tangible objects on a tabletop.

关键词： Apertures   Dielectrics   Antennas   Security   Metals   Wireless communication   Uplink   Electromagnetic shielding   radio frequency identification (RFID)   wireless security  

摘要： Radio frequency identification (RFID) is a widely used approach for a short-range contactless data exchange, i.e., employed in billing systems. During the last years, unauthorized access has become an issue, as it has been proven on numerous unpleasant occasions. A typical theft scheme is based on approaching a victim with a card reader. However, a straightforward adaptation of the reader's antenna elements allows performing the attack from a distance, opening a severe security loophole. Here, we propose and demonstrate hardware-based protection capable of preventing a far-field attack of this kind. Our solution is based on an RFID chip shielding with an opaque metal. The Faraday type of the enclosure has a small aperture, which suppresses electromagnetic field leakage from the device. This property affects both up and down interrogation links, virtually making the far-field attack impossible. Activation of the card is done by holding it in hand-this way, it is made accessible to an authorized readout, which still remains wireless. The physical principle of the operation is placing a high-index dielectric structure next to a subwavelength aperture, making it electromagnetically larger and, as a result, supporting the field leakage. Our experimental prototype, validated by several different users, shows the capability to diminish far-field attacks on ultrahigh frequency (UHF) RFID tags. This hardware security solution can find usage in numerous applications, such as biometric passports, credit cards, and many others, where unauthorized access to sensitive data is highly undesirable.

关键词： chipless sensor radio-frequency identification   frequency selective surfaces   item encoding   polyamide   Kapton   relative humidity   radar cross section  

摘要： This paper presents a polarization-independent 11-bit chipless RFID tag based on frequency-selective surface which has been designed for encoding and relative humidity (RH) sensing applications. The 10 exterior U-shaped resonators are used for item encoding whereas Kapton has been incorporated with the interior resonator for RH sensing. This radio-frequency identification (RFID) tag operates in S- and C-frequency bands. The proposed design offers enhanced fractional bandwidth up to 88% with the density of 4.46 bits/cm(2). Both single- and dual-layer tags have been investigated. The simulated results are in good agreement with measured results and a comparison with existing literature is presented to show the performance. Simple geometry, high code density, large frequency signature bandwidth, high magnitude bit, high radar cross-section, and angular stability for more than 75 degrees are the unique outcomes of the proposed design. In addition, RH sensing has been achieved by integrating the Kapton on the same RFID tag.

关键词： Amplitude   backscatter   chipless   RFID   UWB-IR  

摘要： In order to encrypt/encode data based on the magnitude level of the radar cross-section (RCS), we propose an approach with a precise estimation considering the resonant characteristics of a multipatch backscatter-based chipless radio frequency identification (RFID) dedicated for chipless tags depolarization. The working principle is based on the polarization mismatch between the tag and the reader antenna to control the magnitude of the backscatter, which allows a reliable detection in real environments. We introduce in this paper a new 4-bit chipless RFID tag with an enhanced RCS, based on a triangular patch antenna with multiple resonators. Additionally, we propose an ultra-wideband impulse radar (UWB-IR)-based reader that interrogates the chipless tag with a UWB pulse, and the received backscatter was studied in both time- and frequency-domains. The antenna was operating from 4.7 to 6.1 GHz, a band allocated for RFID systems. The obtained experimental measurement results in the environment of anechoic chamber were exceptionally relevant to validate the simulation results.

关键词： passive wireless sensor   high temperature application   LC resonator   metamaterial   RFID   indium tin oxide   electroconductive ceramic sensor   solid-state sensor   ceramic capacitor  

摘要： In this work, an all-ceramic passive wireless inductor-capacitor (LC) resonator was presented for stable temperature sensing up to 1200 degrees C in air. Instead of using conventional metallic electrodes, the LC resonators are modeled and fabricated with thermally stable and highly electroconductive ceramic oxide. The LC resonator was modeled in ANSYS HFSS to operate in a low-frequency region (50 MHz) within 50 x 50 mm geometry using the actual material properties of the circuit elements. The LC resonator was composed of a parallel plate capacitor coupled with a planar inductor deposited on an Al2O3 substrate using screen-printing, and the ceramic pattern was sintered at 1250 degrees C for 4 h in an ambient atmosphere. The sensitivity (average change in resonant frequency with respect to temperature) from 200-1200 degrees C was similar to 170 kHz/degrees C. The temperature-dependent electrical conductivity of the tin-doped indium oxide (ITO, 10% SnO2 doping) on the quality factor showed an increase of Q(f) from 36 to 43 between 200 degrees C and 1200 degrees C. The proposed ITO electrodes - displayed improved sensitivity and quality factor at elevated temperatures, proving them to be an excellent candidate for temperature sensing in harsh environments. The microstructural analysis of the co-sintered LC resonator was performed using a scanning electron microscope (SEM) which showed that there are no cross-sectional and topographical defects after several thermal treatments.

关键词： Transportation   M-RFID   GPS   LBS   Black spot   Exposure   Likelihood   Impact  

摘要： The need of developing systems that address traffic matters such as traffic control and accidents has led to the development of a number of techniques, methods and tools to address road usability issues. Many automated models have been proposed and applied in different scenarios such as road oddities. Despite of the advantages of these models the major problem of road accidents continue to pose problem glob-ally. This has created the need to come up with more user-effective approaches to address road accidents. Main objective of this research therefore is to identify and address the gap in Location Based Services (LBS). A model that combines RFID and GPS technology to provide Location Based Services via audio alerts to drivers as they approach black spots is presented. The model provides location based services to dri-vers as they approach black spots causing them to adjust their driving accordingly (i.e. speeding, overtak-ing). Since LBS technologies have different limitations, most researchers have focused on addressing accuracy limitation by proposing hybrid technologies. Accuracy requirement varies depending on appli-cation area. The analysis of the different technologies revealed that in vehicle transportation medium accuracy is effective. This research focused on availability aspect which is a key requirement in LBS. To achieve this a model made up of RFID & GPS is formulated. Higher availability of significant alerts at black spots is registered through simulation as compared to alerts when the technologies are applied sepa-rately. Black spot accidents are therefore managed due to safer driving around black spots. This can lead to reduction in exposure to accidents, likelihood of occurrence and impact in the event of an incident. Usability metrics is used to determine effectiveness of the model. (c) 2022 THE AUTHORS. Published by Elsevier B.V. on behalf of Faculty of Computers and Information, Cairo University. This is an open access article under the CC BY-N

关键词： chipless RFID   reader antenna   multiple narrow-band   multi-frequency   cubic interpolation  

摘要： In this article, a chipless RFID reader antenna based on a modified rectangular-resonator is presented. The reader antenna is fabricated and measured to validate multiple narrowband resonance behavior. The measurement results show that the reader antenna can detect 11-bit multi-frequency coded chipless tag and depict gains of 4.7 and 5.2 dBi at 0.58 and 2.4 GHz, respectively. The cubic interpolation approach as a signal processing technique is applied at the reader end to eliminate the unnecessary drops at the measurement. Further study of Chu and Mclean's fundamental limit demonstrates that the physical dimensions of the proposed antenna and the radiation characteristics fulfilling the limitations. The multiple narrow-band responses of the reader antenna can be suitable to detect multi-bit tags which are of high demand because a multibit tag can be used for multiple frequency applications for hassle-free wireless environment, viz. tracking, retailing, identification, and healthcare utilities.

关键词： Electro-textile   Interface   UHF-RFID   Antenna   Mix use   On body  

摘要： Textile Ultra High Frequency (UHF, 865-868 MHz) Radio Frequency Identification (RFID) devices meet difficulties from connection of solid chips and textile antennas. In this work, three electro-textile interfaces integrated with the corresponding textile UHF-RFID antennas as the solutions are proposed and compared. The simulated and measured impedance curves of the corresponding antennas are all close and the radiation performance (realized gain) are designed to be near (about 1.4 dBi). According to the Friis formula, the simulated and measured read ranges of the interfaces with the corresponding antennas in air are obtained (all above 4.5 m). For reliability validation, mixed use feasibility tests are implemented and the results show the read ranges of each interface used on other two designs have tolerable read range decrease (< 2 m but all above 3.41 m).In addition, the read ranges of the designs on body are all above 2.05 m. Due to the small sizes of the interfaces, stable performance on body and good reliability, the proposed interfaces solutions are proved feasible.

关键词： Radio frequency identification   Missing tag identification   Highly dynamic system   Time efficiency  

摘要： The future real-world applications is bound up with Radio frequency identification (RFID) technology as it develops dramatically fast, especially in the field of warehouse management and inventory control, etc. In such applications, identifying missing tags to determine which goods are missing is an important issue. However, since only static scenarios with no new tag movement are considered, existing missing tag identification protocols hardly work well in more common dynamic scenarios where there are tags entering the system or missing frequently. In highly dynamic RFID systems, identifying missing tags becomes more challenge under the interference of unknown tags. Existing methods suppress this interference by filtering unknown tags, which is time-consuming and inefficient. In this paper, for high dynamic RFID systems, we propose an efficiently and accurately protocol HDMI to identify missing tags. By combining the reply slot location of the tags and the reply bits, HDMI identifies missing tags and filters the unknown tags simultaneously, which maximizes the slot utilization. We also optimize the setting of key parameters to reduce execution time while ensuring recognition accuracy. Simulation results show that, compared with state-of-art protocols, HDMI has a higher accuracy rate and better time efficiency in identifying missing tags.

关键词： Wireless sensor networks   Wireless communication   Monitoring   RFID tags   Automobiles   Sensors   Radio frequency   Automotive   batteryless   hybrid RFID   sensor  

摘要： In this paper, a hybrid RFID tag and reader system is proposed for wireless and batteryless automotive sensors. The hybrid RFID tag operates in dual mode, which includes conventional RFID operation, and tag active transmission. The reader provides the carrier in conventional RFID communication, using which the tag performs backscatter modulation. In tag active transmit mode, the reader does not provide any carrier, and the tag synthesizes its own carrier for communication. The hybrid tag can communicate with the reader for a range of 21 in. A commercial seat belt sensor was integrated with the tag and a working prototype of the complete system was demonstrated. Time response is a critical parameter for the whole system to work coherently and hence the operational states were modeled for time estimation and address the key parameters. Individual subsystems within the tag and reader circuits are presented in detail to capture the complete system. The proposed system can reduce the effective on-time of the reader significantly and the analysis shows that the reader transmit time can be reduced as much as 90% compared to the conventional RFID reader. The system was validated by designing, fabricating, and testing of the tag and reader circuits within a lab environment.