RF Tags Research Articles

A Passive Harmonic RFID Tag and Interrogator Development

In this paper, a passive harmonic radio frequency identification (RFID) tag and a simple interrogator to actuate the tag and obtain the identity (ID)/IP address from the tag are presented. The harmonic RF tag was implemented using transceiver antennas, a lumped element-based non-linear transmission line (NLTL), an energy harvester and an ultra-low power digital modulation circuit. The digital modulation circuit generated the ID and the NLTL was modulated at that specific ID. The harmonic tag can operate at a minimum received power of −6 dBm. Combining antennas with the tag, a read range of 1.8 m was achieved at a transmitted power of 18 dBm at 434 MHz. A simple interrogator design was proposed to activate the tag and decode the transmitted ID. The design and working principle of the tag along with the interrogator are discussed in detail. The results of this paper are compared to data reported in open literature for alternate RFID designs.

Data Verification in Integrated RFID Systems

Radio frequency identification (RFID) is widely used as a tagging system to facilitate physical transactions in the real world. Thanks to the availability of inexpensive passive RF tags, RFID technology is now the catalyst of Internet of Things, i.e., every object can be uniquely identified in an Internet-like way. In the future, many individual RFID systems are likely to be integrated into a few exascale RFID systems. In an integrated RFID system, service providers (SPs) that offer RFID-based data service and clients that use the data service are different organizations. As a consequence, quality of data in terms of authenticity is of significant concern. In this paper, we first formulate a data verification problem in RFID systems and build a model of integrated RFID systems where multiple SPs and clients exist. Then, we propose two data verification protocols to ensure data generated by SPs associated with a particular tag and has not been modified. In addition, we implement our system as a prototype. The computer simulations, analyses, and testbeds based on the prototype all demonstrate that the proposed verifiable integrated RFID system achieves a high level of security and performance.

Multi-Dimensional Sparse-Coded Ambient Backscatter Communication for Massive IoT Networks

In this paper, we propose a multi-dimensional sparse-coded ambient backscatter communication (MSC-AmBC) system for long-range and high-rate massive Internet of things (IoT) networks. We utilize the characteristics of the ambient sources employing orthogonal frequency division multiplexing (OFDM) modulation to mitigate strong direct-link interference and improve signal detection of AmBC at the reader. Also, utilization of the sparsity originated from the duty-cycling operation of batteryless RF tags is proposed to increase the dimension of signal space of backscatter signals to achieve either diversity or multiplexing gains in AmBC. We propose optimal constellation mapping and reflection coefficient projection and expansion methods to effectively construct multi-dimensional constellation for high-order backscatter modulation while guaranteeing sufficient energy harvesting opportunities at these tags. Simulation results confirm the feasibility of the long-range and high-rate AmBC in massive IoT networks where a huge number of active ambient sources and passive RF tags coexist.

Cooperative Target Tracking and Signal Propagation Learning Using Mobile Sensors

Target tracking refers to positioning mobile objects over time. The targets may be hospital patients, park visitors, mall shoppers, warehouse assets, etc. We consider a novel cooperative system to track targets, where a target carries low-cost RF tag which not only beacons its ID, but also receives and rebroadcasts beacons of tags within a certain hop away. Mobile sensors, equipped with localization and communication modules, are used to capture and forward the beacons to a server to track the targets. Such multi-hop approach greatly extends the sensing range of the mobile sensors, or equivalently, the beaconing range of the tags, leading to cost-effective deployment. We propose Mosent, a highly accurate multi-hop system using mobile sensors for target tracking. To account for complex signal propagation in different indoor and outdoor environment, we represent the received signal strength (RSS) matrix overcoming the assumption on propagation model. Given sensor locations, beacons detected by the sensors and RSS matrix, Mosent jointly considers temporal and spatial information to track targets using a modified particle filter. Mosent has an optional, independent and offline module to learn spatial signal propagation in terms of RSS matrix using cooperative mobile sensors equipped with beaconing transceivers. We have implemented Mosent and conducted extensive experiments. Our results show that Mosent achieves 4.37m and 9.46m tracking error in the campus and the shopping mall, respectively, which outperforms other state-of-the-art approaches with significantly lower tracking error (often by more than 30%).

A Novel RFID Anti-Counterfeiting Based on Bisectional Multivariate Quadratic Equations

This article proposes a novel scheme for RFID anti-counterfeiting by applying bisectional multivariate quadratic equations (BMQE) system into an RF tag data encryption. In the key generation process, arbitrarily choose two matrix sets (denoted as A and B) and a base RAB such that [(AB) ⃗ ]=λ〖R_AB〗^T, and generate 2n BMQ polynomials (denoted as ρ) over finite field F_q. Therefore, (F_q, ρ) is taken as a public key and (A,B,λ) as a private key. In the encryption process, the EPC code is hashed into a message digest d_m. Then d_m is padded to d_m^' which is a non-zero 2n×2n matrix over F_q. With (A,B,λ)and d_m^', s_m is formed as an n-vector over F_2. Unlike the existing anti-counterfeit scheme, the one the authors proposed is based on quantum cryptography, thus it is robust enough to resist the existing attacks and has high security.

Fast and secure tag authentication in large-scale RFID systems using skip graphs

Fast and secure object monitoring and management using Radio Frequency Identification (RFID) technologies is crucial to Internet of Things (IoT) systems. Structured key-based private authentication protocols securely identify individual RF tags in the logarithmic order by having group keys shared by several tags. However, should some portion of tags in the system be physically compromised, the degree of privacy of the other tags will decrease. This is because tampered group keys disclosed from the compromised tags can be correlated. Thus, preserving the degree of tags’ privacy in keeping with fast authentication speed is equivalent to reducing the correlation probability of group keys. Toward this goal, we propose Randomized Skip Graphs-Based Authentication (RSGA) that significantly improves the tags’ privacy in terms of anonymity with reasonable amount of key storage cost by using a skip graph key structure. Then, we augment RSGA with a key updating mechanism to securely update secret keys and a path pruning algorithm to further facilitate its authentication process. Our extensive computer simulation as well as mathematical analyses present that the proposed RSGA achieves its design goals.

Self-Powered Timekeeping and Synchronization Using Fowler–Nordheim Tunneling-Based Floating-Gate Integrators

Self-powered timers provide a mechanism to achieve temporal synchronization between two passive devices (for e.g., RF tags, credit/access cards, and thumb drives) without the need for any external powering or clocks. As a result, the timers could be used to implement dynamic SecureID type authentication involving random keys and tokens that need to be periodically generated and synchronized. We report a novel solid-state self-powered timer, which exploits a self-compensating mechanism in the physics of Fowler–Nordheim quantum transport of electrons tunneling onto a floating gate. The proposed devices have been fabricated using standard CMOS processing and are demonstrated to be operational for durations greater than three years using extrapolation studies. The fabricated devices were also found to be extremely robust to device mismatch and as a result of which, the proposed self-powered timers can be synchronized with respect to each other with an accuracy greater than 0.5%.

COMPENSATION OF TEMPERATURE DISTORTIONS OF PULSE CHARACTERISTICS OF RFID ON THE SURFACE OF ACOUSTIC WAVES WITHIN A WIDE INTERVAL OF WORKING TEMPERATURES

The results of numerical simulation of the temperature code in the form of the five-symbol Barker code for compensation of distortion of the impulse characteristics of the RF tag on the SAW with the time-positioned phase-shift keyed code have been presented. The dependences of the maximum of the WCF of the five-symbol Barker code on the temperature for multiple options of the mutual arrangement of individual pulses forming the temperature code have been investigated.

Magnetolastic Smart Tags Using Electroformed Cobalt Iron Boron

Microfabricated magnetoelastic resonators forming the basis for a new, passive, wireless tagging technology platform have been developed. These magnetoelastic tags operate on the principle of Joule magnetostriction (i.e., a large change in material shape induced by an applied AC magnetic field) to produce magnetic signals and are an alternative technology to existing inductive RF tags. Lithographically patterned and electrochemically deposited (ECD) cobalt iron boron (CoFeB) alloy films are used to create the longitudinal mode magnetoelastic resonators. Due to the greater thickness and low-stress nature of electrodeposited films, these resonators can be released like other MEMS devices via a sacrificial layer to form free-standing structures. This batch fabrication technique also allows for multiple resonators of varying lengths and magnetic bias angles resulting in a multi-frequency signal that becomes the tag identity. Hysteresis curves to measure fundamental material magnetic properties that affect tag performance such as magnetic saturation, coercivity, and susceptibility were measured. Process flows for microfabricating resonators along with resonator design, modeling and characterization results will be presented. Future design concepts for tags with environmental sensing functions using this novel material set will be briefly discussed.

스마트 웰니스 로봇 플랫폼 개발에 관한 연구

본 논문에서는 노령화 사회에서 노인들의 기본 건강과 생활을 케어 할 수 있는 홈 웰니스 로봇 플랫폼을 개발한다. 실내 환경에서 웰니스 서비스에 초점을 맞추어 로봇 및 센서 플랫폼을 구현한다. 로봇플랫폼에서는 정밀제어 이동기능과 정교한 로봇 팔 및 핸드를 개발하고 인간친화형 로봇구조로 설계되어진다. 이동로봇은 옴니휠 기반의 쾌속 시스템으로 제어된다. 로봇팔은 섬세한 조작기능을 수행할 수 있도록 인간의 팔과 유사한 구조로 구현한다. 센서 플랫폼에서는 RF태그와 스테레오 카메라를 활용하여 로봇자신과 대상물체의 위치 인식시스템을 구축한다. 정확한 위치와 자세 인식을 위하여 센서 융합 알고리즘이 제안된다. 끝으로 웰니스 로봇 플랫폼의 좋은 성능들이 실시간 시험 구동을 통하여 확인되어 진다. This paper developed a home wellness robot platform to perform the roles in basic health care and life care in an aging society. A robotic platform and a sensory platform were implemented for an indoor wellness service. In the robotic platform, the precise mobility and the dexterous manipulation are not only developed in a symbiotic service-robot, but they also ensure the robot architecture of human friendliness. The mobile robot was made in the agile system, which consists of Omni-wheels. The manipulator was made in the anthropomorphic system to carry out dexterous handwork. In the sensing platform, RF tags and stereo camera were used for self and target localization. They were processed independently and cooperatively for accurate position and posture. The wellness robot platform was integrated in a real-time system. Finally, its good performance was confirmed through live indoor tests for health and life care.

From radio telemetry to ultra-low-power sensor networks: tracking bats in the wild

Sensor networks have successfully been used for wildlife monitoring and tracking of different species. When it comes to small animals such as smaller birds, mammals, or even insects, the current approach is to use extremely lightweight RF tags located using radio telemetry. A new quantum leap in technology is needed to overcome this limitation and enable new ways to observe larger numbers of small animals. In an interdisciplinary team, we are working on the different aspects of such a new technology. In particular, we report on our findings on a sensor- network-based tracking solution for bats. Our system is based on integrated localization and wireless communication protocols for ultra-lowpower systems. This requires coding techniques for improved reliability as well as ranging solutions for tracking hunting bats. We address the technological and methodical problems related to system design, software support, and protocol design. First field experiments have been conducted that showcase the capabilities of our system.

Analysis of RFID Based Positioning Technique Using Received Signal Strength and Directional Antenna

Automatic robot navigation is being utilized in many industries for the purpose of high speed work delivery. Color follower, fix path follower robots are current solution to this activities but dynamic path configuration is not possible in these robots. Hence new system proposes effective and fully dynamic path follower robots using RFID and directional antenna. Radio Frequency Identification (RFID) system permits automatic identification of objects with RFID tags using radio waves which have been widely used in mobile robot navigation, localization and mapping both in indoor and outdoor environment. This article presents a navigation strategy for autonomous mobile robot using passive RFID system. Proposed robot system is provided with RFID tag functionality which will load tag number and direction instruction. At some turning point, user will put RF tag, this tag will be read by RF reader which is placed on robot. As per direction instruction robot will change the direction and reach to the destination. Also as per the movement, robot will send its GPS location to PC (Personal Computer) which will be displayed on PC. Hence main goal is to provide more reliable and low energy consumption based indoor positioning system which will be achieved using directional antenna.

A Low-IF Tag-Based Motion Compensation Technique for Mobile Doppler Radar Life Signs Monitoring

This paper presents low IF techniques for noninvasive detection of vital signs from a mobile short-range Doppler radar platform. Stationary continuous-wave Doppler radar has been used for displacement measurement and vital signs detection. However, on a mobile platform, measurements become challenging due to motion artifacts induced by the platform. In this work, a complete compensated single transceiver radar system for vital signs detection in the presence of platform movement is demonstrated. In earlier related work, motion of the radar module was determined using cameras installed on site. However, practical mobile monitoring applications would preclude the use of such stationary cameras. In this work, an RF tag and a low IF radar architecture with an adaptive noise cancellation technique is employed to extract desired vital signs motion information even in the presence of large platform motion.

Working on the Railroad

When people learn that over one million railcars in North America are equipped with two radio-frequency identification (RFID) tags, they are surprised. When they are also told that the railcars have been equipped with RF tags for over 20 years, they are shocked. Most people's perception of the railroads is that it is an old industry that is slow to adopt new technology. This is far from the truth.

Design and Implementation about Secure Smart Electricity Meter Sealing Based on RF Tag

Design and Implementation about Secure Smart Electricity Meter Sealing Based on RF Tag

Enhancement of RF Tag Backscatter Efficiency With Low-Power Reflection Amplifiers

Increasing backscatter tag communication ranges is crucial for the development of low-power long-range wireless sensor networks. A major limitation for increasing the signal-to-noise ratio (SNR) for RF identification tags lies in the fact that tag antennas are terminated with passive loads for modulation, which yields reflection-coefficient values less than unity. Recent work in the field has exploited reflection amplifiers that achieve reflection-coefficient values larger than unity to increase the communication range. However, most of these systems rely on increasing the reflection coefficient at one modulation state only, which is suboptimal. In this paper, an analysis is given for the optimal way to utilize a reflection amplifier and how this compares to suboptimal practices. To demonstrate the concept, a tag is designed that achieves reflection-coefficient values higher than unity for both states in the 900-930-MHz band. The two values are antipodal, thus maximizing the tag SNR for a given amplifier. The system comprises of an ultra-low-power reflection amplifier with up to 10.2-dB gain and sub-milliwatt power consumption, and a phase-shift modulator that selectively alternates the phase of the backscatter signal between 0 ° and 180 ° . The reflection amplifier-phase modulator system is experimentally characterized in terms of gain, power consumption, and backscatter efficiency.

Printed Transistors on Paper: Towards Smart Consumer Product Packaging

The integration of fully printed transistors on low cost paper substrates compatible with roll‐to‐roll processes is demonstrated here. Printed electronics promises to enable a range of technologies on paper including printed sensors, RF tags, and displays. However, progress has been slow due to the paper roughness and ink absorption. This is solved here by employing gravure printing to print local smoothing pads that also act as an absorption barrier. This innovative local smoothing process retains desirable paper properties such as foldability, breathability, and biodegradability outside of electronically active areas. Atomic force microscopy measurements show significant improvements in roughness. The polymer ink and printing parameters are optimized to minimize ink absorption and printing artifacts when printing the smoothing layer. Organic thin film transistors (OTFT) are fabricated on top of this locally smoothed paper. OTFTs exhibit performance on par with previously reported printed transistors on plastic utilizing the same materials system (pBTTT semiconductor, poly‐4‐vinylphenol dielectric). OTFTs deliver saturation mobility approaching 0.1 cm2V–1s–1 and on‐off‐ratio of 3.2 × 104. This attests to the quality of the local smoothing, and points to a promising path for realizing electronics on paper.

Performance Improvement of Group Coding with RF Tags on Missing Objects Detection and Data Recovery

Radio Frequency Identification (RFID) provides a non-line-of-sight and contactless approach for object identification. In the supply chain, objects are usually assembled into a group and RFID system enables us to quickly identify a group of objects. However, RFID system only provide the identified objects ID, unable to provide the missing objects IDs. This paper concerns the problem of missing objects detection and missing unique IDs recovery. In supply chain, a traditional method of items lost detection is encoding a group of objects ID before the shipment, and decoding when examine the integrity of the objects. In this paper, we propose a new scheme for missing objects detection and missing IDs recovery, which is called Linearly Independent Vectors Based Group Coding, abbreviated LIVGC. A numerical simulation reveals that the proposed method have higher recovery rate (>20%) than the EGC scheme in the same length of redundancy code.

OBSTACLE DETECTION AND ELECTRONIC NAVIGATION SYSTEM FOR VISUALLY IMPAIRED PERSONS

In This Paper we present a real time domain obstacle detection system for the visually impaired persons to improve their mobility in daily life with the help of obstacle detection sensor installed in their walking stick .System is having a lower cost so it is easily purchasable so it can have a major significance in life of visually impaired persons. This Paper proposes a system to detect any object attached to the floor regardless to their height [1]. Obstacle on the floor in the front of user can be reliably detected in real time using the proposed system implemented by the IR sensor installed on the walk stick of the visually impaired person. Project also contains a navigation system for visually impaired persons to make the life of such persons easier up to some extent. This project is suited for the area where the possibility of blind person is high (like blind school, college)[6]. For transport facility of blind we have first decided the common bus roots of blind then we have placed RF tag to all those buses with unique code. At the second side we have placed RF reader, microcontroller and voice processor. The RF reader receive unique code, microcontroller process this code with defined code, if match found, voice processor get activated and starts speaking bus name, initial destination and final destination. The obstacle detection is also included in the project with voice. The system aims at increasing the mobility of visually impaired people by offering new sensing abilities.

Adaptive Noise Cancellation for Two Frequency Radar Using Frequency Doubling Passive RF Tags

The use of an adaptive noise-cancellation technique has been explored in order to separate multiple sources of motion for a two-frequency Doppler radar system. A 2.45-GHz fundamental Doppler radar system was used together with a harmonic Doppler radar receiver to measure and identify two moving reflectors; one with a harmonic tag and one without. While the tagged motion alone was detected by the harmonic receiver, least mean squares and normalized least mean squares algorithms were applied to the fundamental receiver output to filter out the tagged-related motion content and successfully isolate the information content associated with only the non-tagged motion. Simulations were performed to study the effect of various parameters on the performance of the algorithms, and experiments were conducted to validate the feasibility of the method.