Traditional RFID Research Articles

An Innovative Method Based on Wavelet Analysis for Chipless RFID Tag Detection

Chipless RFID tags have attractive low-cost advantages. However, traditional RFID anti-collision algorithms cannot be applied due to a lack of computing and processing capabilities. Problems with multitag detection must be solved to commercialize chipless RFID tags. In this paper, an innovative method for frequency-domain chipless RFID tag detection is proposed. The tags’ scattered signals are processed via wavelet analysis, and a time–frequency plot that can read the code is obtained. When the distance between tags is too close to distinguish in the time–frequency plot, independent component analysis is used to separate individual scattered signals from mixed echo signals; then, the code is read by means of wavelet analysis. To validate the proposed method, C-shaped frequency-domain chipless RFID tag models and a multitag detection simulation scenario were constructed in selected software. The short-time matrix pencil method (STMPM), short-time Fourier transform (STFT), and the proposed method were compared. When the tag spacing is 0.05 m, the code can be read successfully. Compared with the STMPM, the proposed method greatly reduces the computational quantity and shortens the reading time. Furthermore, adjustment of the window width and search step parameters is avoided.

A Fully Integrated RFID Reader SoC.

The traditional RFID reader module relies on a discrete original design. This design integrates a microcontroller, high-frequency RFID reader IC and other multiple chips onto a PCB board, leading to bottlenecks in cost, power consumption, stability and reliability. To align with the trend towards high integration, miniaturization and low power consumption in RFID reader, this paper introduces a fully integrated RFID Reader SoC. The SoC employs the open-source Cortex-M0 core to integrate the RF transceiver, analog circuits, baseband protocol processing, memory and interface circuits into one chip. It's compatible with ISO/IEC 14443 A-type and B-type and ISO/IEC 15693 transmission protocols and rates. Manufactured using a 0.18 μm process, the chip is compatible with multiple standards. The optimized design of the digital baseband control circuit results in a chip area of only 11.95 mm2 offering clear advantages in both area and integration compared to similar work.

Combined Temperature and Humidity Chipless RFID Sensor

A temperature and humidity chipless RFID sensor is presented in this paper. The tag ID as well as the two physical parameters are extracted using a traditional chipless RFID tag and interrogation procedure. No specific material, i.e. particularly sensitive to the quantities to be measured, is used for ease of implementation. The method is based on a model which describes precisely the evolution of the scatterer’s resonance frequency as a function of temperature and humidity. The materials permittivity (impacted by these two quantities) and dilatation (impacted only by the temperature) are taken into consideration to estimate these two physical quantities independently and simultaneously using only the measurement of the resonance frequencies of two scatterers. Measurements in a controlled environment and in a real environment are achieved showing the potential of this approach for the sensor application. The sensing limitation as well as the possibility of this approach to characterize the temperature and humidity dependencies of unknown materials are also presented.

Design of a new anti-metal RFID temperature tag antenna based on short-circuit stub structure

With the increasing maturity of the power Internet of things (pIoT), radio frequency identification technology (RFID), is more applied to the fault monitoring of power equipment, of which the temperature monitoring of power equipment is one of the focuses of fault monitoring. When the traditional RFID temperature measurement tag is applied to high-voltage electrical equipment, it often produces metallic interference to the RFID temperature measurement tag antenna because it is attached to the surface of metal conductor, such as large synchronous machine and high-voltage transmission line, which greatly shortens the identification range of the traditional RFID temperature measurement tag on the metal surface and even cannot work normally. To solve the problems above, a new anti-metal RFID temperature tag antenna is designed in this paper. The internal antenna of the RFID temperature measurement tag adopts the anti-metal design based on the short-circuit stub structure, so that the temperature measurement tag can achieve the purpose of good anti-metal performance. Finally, through the simulation of HFSS, this paper verifies that the designed RFID temperature measurement tag can not only resist metal effect, but also be well applied to complex metal environment.

Closed-loop and open-loop authentication protocols for blockchain-based IoT systems

Designers of smart environments based on radio frequency identification devices have a challenging task to build secure mutual authentication protocols. These systems are classified into two major factions which are traditional closed-loop systems, and open-loop systems. To the best of our knowledge, all of the mutual authentication protocols previously introduced for these two categories rely on a centralized database but they fail to address decentralized mutual authentication and their related attacks. Thanks to the blockchain technology, which is a novel distributed technology, in this paper, we propose two decentralized mutual authentication protocols for IoT systems. Our first scheme is utilized for traditional closed-loop RFID systems (called CLAB), and the second one applies to open-loop RFID systems (called OLAB). Meanwhile, we examine the security of the Chebyshev chaotic map-based authentication algorithm and confirm that this algorithm is unprotected against tag and reader impersonation attacks. Likewise, we present a denial of service (DoS), tag impersonation, and reader impersonation attacks against the Chebyshev chaotic-map based protocol when employed in open-loop IoT networks. Moreover, we discover a full secret recovery attack against a recent RFID mutual authentication protocol which is based on blockchain. Finally, we use the BAN-logic method to approve the security characteristics of our CLAB and OLAB proposals.

ROPHS: Determine Real-Time Status of a Multi-Carriage Logistics Train at Airport

Tracking ground support equipment (GSE) in a high accuracy manner is crucial for both airport safety and optimal management of airport assets but the related researches and products are scarce. Tracking a multi-carriage logistics train is obviously most challenging compared with other single-carriage GSE. In this paper, we design a real-time on-board positioning and heading system (ROPHS) to obtain the real-time status of a multi-carriage logistics train which consists of a powered leading vehicle and one or several non-powered trailing vehicles. The status includes: (a) the accurate positions and velocities of any points on this train, and (b) the alterable number and linking sequence of trailing vehicles at any time of a trip. Technically, the hardware of the system relies on real-time kinematic (RTK) to obtain geolocation of the leading vehicle, and on gyroscopes, magnetometers and accelerometers to obtain headings of all vehicles. A geometry based recurrence algorithm is afterwards presented to calculate the positions of any trailing vehicles. In the end, the multiple model based tracking algorithm is proposed to compute the precision-improved locations and real-time velocities of the whole train. Different from existing traditional GPS or RFID based positioning techniques, the proposed system can reach centimeter-level accuracy, which enables collisions detection, especially those latent collisions that cannot be easily monitored or foreseen by crews’ visual inspection.

Super Lightweight Mobile RFID Authentication Protocol for Bit Replacement Operation

In the traditional RFID system, the secure wired channel communication is used between the reader and the server, and the new mobile RFID system is different from the traditional RFID system. The reader and the server communicate based on the wireless channel. This makes authentication protocols applicable to traditional RFID systems not applicable to mobile RFID systems. To solve this defect, a two-way authentication protocol MSB is proposed for ultra-lightweight mobile radio frequency identification system based on bit replacement operation. MSB (most significant bit) encrypts information based on bitwise operations, and the amount of computation of the communication entity is reduced. Tags, readers, and servers first authenticate and then communicate. MSB can be resistant to common attacks. The security analysis of the protocol shows that the protocol has high security attributes, and the performance analysis of the protocol shows that the protocol has the characteristics of low calculation volume. The formal analysis of the protocol is given based on GNY logic.

An octagonal-shaped conductive HC12 & LIBERATOR-40 thread embroidered chipless RFID for general IoT applications

This paper presents the design, fabrication and testing of two embroidered chipless octagonal-shaped RFID tags on cotton fabric for wearable applications. The first tag is designed by using silver-coated polyamide conductive fibre (HC12) and the second tag is embroidered by using highly conductive Vectran (LIBERATOR 40) which is highly conductive multifilament yarn spun from Liquid Crystal Polymers (LCP), on cotton fabrics. In contrast to the traditional RFID tag, the chipless RFID tagging, the ID code is not saved in the memory, instead, it uses the physical features of the tag to send data. The proposed tag's design uses a Frequency Selective Surface (FSS) technique for the frequency range of 8–18 GHz. These tags are designed using CST studio and precisely fabricated by using commercial ZSK Technical Embroidery System JCZA (0109–550). The tag design is composed of six concentric octagonal loop resonators with one unitary element. The electromagnetic scattering waves behaviour and Singularity Expansion Method (SEM) based circuit modelling for the octagonal-shaped tag is performed, and the coupling coefficients are evaluated. The desired data bits are obtained by a series of comparative experiments for Radar Cross Section (RCS) in an anechoic chamber. The experimental results obtained show that the 4-bit data is accurately retrieved with the variation of distance by up to 1.8 m at 0 dB m. Moreover, the average transition from minimum ‘0’ to maximum 1’ is -27 dB for both designs. Furthermore, the experimental results for on-body RCS measurements and the bending effects on both tags down to 7 mm is observed. This octagonal embroidered Chipless RFID tag is a fully textile design which is compact and can be deployed commercially in various IoT applications.

Optimal data transmission in backscatter communication for passive sensing systems

Computational Radio Frequency IDentification (CRFID) is a device that integrates passive sensing and computing applications, which is powered by electromagnetic waves and read by the off-the-shelf Ultra High Frequency Radio Frequency IDentification (UHF RFID) readers. Traditional RFID only identifies the ID of the tag, and CRFID is different from traditional RFID. CRFID needs to transmit a large amount of sensing and computing data in the mobile sensing scene. However, the current Electronic Product Code, Class-1 Generation-2 (EPC C1G2) protocol mainly aims at the transmission of multi-tag and minor data. When a large amount of data need to be fed back, a more reliable communication mechanism must be used to ensure the efficiency of data exchange. The main strategy of this paper is to adjust the data frame length of the CRFID response dynamically to improve the efficiency and reliability of CRFID backscattering communication according to energy acquisition and channel complexity. This is done by constructing a dynamic data frame length model and optimizing the command set of the interface protocol. Then, according to the actual situation of the uplink, a dynamic data validation method is designed, which reduces the data transmission delay and the probability of retransmitting, and improves the throughput. The simulation results show that the proposed scheme is superior to the existing methods. Under different energy harvesting and channel conditions, the dynamic data frame length and verification method can approach the theoretical optimum.

Probing into the Physical Layer: Moving Tag Detection for Large-Scale RFID Systems

Logistics monitoring is a fundamental application that utilizes RFID systems to manage numerous tagged-objects. Due to the frequent rearrangement of tagged-objects, a fast RFID-based tracking approach is highly desired for accurate logistics distribution. However, traditional RFID systems usually take tens of seconds to interrogate hundreds of RFID tags, not to mention the time delay involved to locate all the tags, which severely prevents from in-time tracking. To address this issue, we reduce the problem domain by first distinguishing the motion status of the tagged-objects, i.e., “stationary” or “moving”, and then tracking the moving objects with the state-of-the-art localization schemes, which significantly reduces the efforts of tracking all the objects. Toward this end, we propose a moving tag detection mechanism, which achieves the time efficiency by exploiting the useless collision signal in RFID systems. In particular, we extract two kinds of physical-layer features (namely, phase profile and backscatter link frequency ) from the collision signal received by the USRP to distinguish tags at different positions. We further develop the Graph Matching (GM) method and Coherent Phase Variance (CPV) method to detect the moving tagged-objects. Experiment results show that our approach can accurately detect the moving objects while reducing 80 percent inventory time compared with the state-of-art solutions.

Design of Secure Enhanced Privacy Protection Electronic Hotel-card Based on QR Code

The development of the Internet and economy urges researchers to look for a safe and more economical way to secure online hotel-users’ private information. This study is rooted in online-hotel user personal privacy and some information protection. The traditional RFID hotel-room card was replaced by the proposed QR e-ID, which combines cryptography, verification code, passwords and multi-directional identity authentication module. All of the privacy information should be registered in the data register center (DRC) with encrypted mode. In order to ensure safety in case if the QR e-ID is used by unknown person it needs a password. The main goal of this study is to investigate how the co-use of computers and mobile devices protect online hotel-users’ private information, in addition, reduce the hotel operating costs effectively. The results of the study also provide guidelines to IT developers for future directions in virtual assets protection.

Application-Adaptable Chipless RFID Tag.

Chipless RFID has gained prominence due to its application versatility and cost and complexity advantages over traditional RFID. However, chipless RFID tags are typically designed for a specific application instead of being deployable for a multitude of applications. In this paper, a new approach to adaptable chipless RFID tag is proposed that can be optimized for a variety of applications, including materials characterization with tags as embedded sensors. Additionally, the designed approach renders tags that can be interrogated with a linearly polarized probe and achieves bit densities up to 27.57 bits/cm2.

A re-transmitted chipless tag using CSRR coupled structure

To reduce the cost of the traditional RFID tags, a re-transmitted chipless tag based on high Q CSRR structure working on UWB frequency band is proposed, which is composed of two orthogonal polarization transmitting and receiving microstrip broadband monopole antennas, loaded with multiple CSRR resonators. Data encoding is utilized the hybrid encoding technology by the significantly spectral signature of the high-Q CSRR resonator and the different amplitude on the same frequency point. The coding capacity is achieved 84 bits, which is far greater than other structures chipless tag. Several typical re-transmitted chipless tags based on CSRR structure are designed by HFSS software. The results of simulation and test are well agreeable to verify the feasibility of the proposed tag such tag, and it has low cost, narrow bandwidth and compact structure. It can be applied to low-cost logistics, production line management and other fields.

A Novel Hybrid Anticollision Algorithm for RFID System Based on Grouped Dynamic Framed Recognition and Binary Tree Recursive Process

Recently, RFID technology has come into end-user applications for monitoring, tracking, and so forth. In RFID system, a reader identifies a set of tags over a shared wireless channel. When multiple tags communicate with the same reader simultaneously, all packages will be lost and no tag can be recognized, which is known as tag collision. Tag collision is a significantly important issue for fast tag identification. We firstly make a thorough analysis among a variety of traditional RFID anticollision algorithms. Then a novel hybrid anticollision algorithm called T-GDFSA is proposed. Tags are assigned to different groups based on the initial tag estimation and then experience several dynamic read frames for identification. When a collision occurs in current slot, a tree-based recursive process will be deployed immediately. T-GDFSA combines the advantages of ALOHA-based and tree-based together and acquires higher system throughput by reducing unnecessary idle and collision slots and lower communication complexity by decreasing the data transmitted, which makes it identify tags faster with less power consumption. Simulations show that the theoretical values match well the simulation results. Moreover, T-GDFSA also has a good tolerance for the inaccuracy of initial tag estimation and the length variation of tag's ID.

Achieving Collision-Free Communication by Time of Charge in WRSN

The Wireless Identification and Sensing Platform (WISP) Sample et al. (IEEE T Instrum Meas 57(11):2608---2615, 2008) has become a very promising experimental platform of wireless rechargeable sensor networks (WRSN), which integrates the sensing and computation capabilities to the traditional RFID tags. In such kind of networks, the simultaneous transmission may introduce severe communication collisions, which have attracted various research efforts for resolving such collisions at the MAC layer. However, different from existing works, we avoid such communication collisions through proper reader movement by exploiting the differences in the time of charge among rechargeable sensor nodes. We formulate the optimization problem and prove that complexity of the optimal solution is NP-hard, and propose a simple yet effective algorithm to optimize both the reader stop location and stop time for minimizing the total communication delay. Extensive simulations under different system settings show that our design can largely reduce the communication delay and outperform the baseline design by at least 20 %.

항만물류 특성을 반영한 컨테이너 정보시스템 설계

항만물류는 그 특성상 global visibility와 traceability가 요구된다. 그러나 현재까지 항만물류에 적용된 전통적인 RFID기술로는 이러한 요구에 부응할 수 없다. 최근의 IP-USN 또는 M2M과 같은 기술들은 네트워크가 구성되어 있어야 한다는 전제와 대량의 컨테이너가 장치되어 있는 항만물류 거점에서는 폭발적인 통신량으로 인한 문제가 발생한다. 또한 최근의 항만물류 관련 이해관계자들의 요구는 보다 적극적인 대응을 할 수 있는 기술과 방법을 요구하고 있다. 이러한 요구와 문제를 해결하기 위해 본 논문에서는 IP-RFID 기반의 스마트 항만물류서비스시스템을 제안한다. IP-RFID 기반의 스마트 항만물류서비스시스템은 스마트 RFID 태그와 센서, 그리고 인터넷에 연결해 주는AP를 태그와 분리하여 통신 문제를 해결하였다. 온도센서, 습도센서, 충격센서, GPS 등이 연결된 태그는 컨테이너에 부착되어 언제 어디서든 원하는 정보를 실시간으로 획득할 수 있어 글로벌한 추적과 투명성을 보장받을 수 있다. The nature of port logistics requires global visibility and traceability. However, the traditional RFID technology still applied cannot meet these demands. IP-USN and M2M in port logistics have faced challenges of the prerequisite of network composition and immense communications at the base where a grand number of containers are installed. To resolve the issue, this study suggests an IP-RFID-based smart port logistics service platform. The IP-RFID-based port logistics service system resolved the communication problem by separating the RFID tag and AP, which allows internet connection, from the tag. The tags connected with thermo-sensors, humidity sensors, pressure sensors, GPS, etc. are attached to the containers insuring global visibility and traceability, key factors in logistics, by obtaining desired real-time information regardless of time and location.

Cloud-Based RFID Mutual Authentication Protocol without Leaking Location Privacy to the Cloud

With the rapid developments of the IoT (Internet of Things) and the cloud computing, cloud-based RFID systems attract more attention. Users can reduce their cost of deploying and maintaining the RFID system by purchasing cloud services. However, the security threats of cloud-based RFID systems are more serious than those of traditional RFID systems. In cloud-based RFID systems, the connection between the reader and the cloud database is not secure and cloud service provider is not trusted. Therefore, the users have to encrypt their data stored in the cloud database to prevent the leakage of privacy. In addition, the reader’s location privacy should be protected to avoid its leak to the cloud provider. In this paper, a cloud-based RFID mutual authentication protocol without leaking location privacy to the cloud is proposed. It provides real-time mutual authentication between the reader and the tag and protects the reader’s location privacy by introducing the location privacy cloud. Compared with traditional backend-server-based schemes and serverless schemes, the proposed scheme has obvious advantages in deployment cost, scalability, real-time authentication, and the tag’s computational complexity.

A potential weakness in RFID-based Internet-of-things systems

In recent years, a large body of research has been devoted to the security and privacy of RFID that is expected to become a critical component of IoT (Internet of Things). Most of these studies have been conducted under the assumption that an RFID system consists of the following elements: RFID tags, a reader and a back-end server. However, in IoT scenario it is supposed that a high density of RFID readers will be deployed and networked to the system over the Internet. Hence, a multi-reader RFID environment circumstance, where readers may be mobile handsets like mobile phones, should be involved in the security analysis of RFID based IoT systems. In this paper, we point out that RFID authentication protocols in the IoT need new security mechanisms that consider untrustworthy RFID entities, compromised readers or insecure communication channel between the readers and the back-end servers. Thus, traditional RFID security schemes designed for closed-loop systems cannot fulfill security and privacy demands, if they are directly adapted to the IoT environment. To emphasize this discrimination, we demonstrate that a secure protocol in a closed-loop RFID system may jeopardize the security of the system in this new RFID concept. Furthermore, we address this fault by investigating the security of a recent IoT RFID authentication protocol, named as AKE-MRFID. We exploit security flaws that have gone unnoticed in the design and present three attacks: de-synchronization, replay and reader impersonation attacks. To defend against the aforementioned attacks, we amend the protocol with a stateful variant so that it holds the claimed security properties.

Context-Aware Defenses to RFID Unauthorized Reading and Relay Attacks

Many RFID tags store valuable information privy to their users that can easily be subject to unauthorized reading, leading to owner tracking, or impersonation. RFID tags are also susceptible to different forms of relay attacks. This paper presents novel sensing-enabled defenses to unauthorized reading and relay attacks against RFID systems without necessitating any changes to the traditional RFID usage model. Specifically, this paper proposes the use of cyber-physical interfaces, on-board tag sensors, to (automatically) acquire useful contextual information about the tag's environment (or its owner, or the tag itself). First, such context recognition is leveraged for the purpose of selective tag unlocking-the tag will respond selectively to reader interrogations. In particular, novel mechanisms based on an owner's posture recognition are presented. Second, context recognition is used as a basis for transaction verification in order to provide protection against a severe form of relay attacks involving malicious RFID readers. A new mechanism is developed that can determine the proximity between a valid tag and a valid reader by correlating certain (specifically audio) sensor data extracted from the two devices. Our evaluation of the proposed mechanisms demonstrate their feasibility in significantly raising the bar against RFID attacks.

Single tag sharing scheme for multiple-object RFID applications

RFID systems have been widely adopted in various industrial as well as personal applications. However, traditional RFID systems are limited to address only one tag for each application object. This limitation hinders the usability of RFID applications because it is difficult, if not impossible, to distinguish many tags simultaneously with existing RFID systems. In this paper, we propose a new RFID tag structure to support multiple-objects that can be easily shared by many different RFID applications. That is, the proposed RFID tag structure supports that a tag maintains several different objects and allows those applications to access them simultaneously. We also propose an authentication protocol to support multiple-object RFID applications. Especially, we focus on the efficiency of the authentication protocol by considering different security levels in RFID applications. The proposed protocol includes two types of authentication procedures. In the proposed protocol, an object has its security level and goes through one of different authentication procedures suitable for its security level. We report the results of a simulation to test the performance of the proposed scheme. In our simulation, we considered the safety of our scheme against potential attacks and evaluated the efficiency of the proposed protocol.