Radio Frequency Identiflcation Tag Research Articles

A NOVEL DESIGN OF COMPACT DIPOLE ANTENNA FOR 900 MHZ AND 2.4 GHZ RFID TAG APPLICATIONS

A novel design of fractal dipole antenna has been presented for RFID (Radio Frequency Identiflcation) tag applications, which is based on the fractal theory. The antenna consists of two third iteration triangle fractal arms, and has been designed to work at 900MHz (GSM) and 2.4GHz (ISM), and its size is 89mm£29mm£1:6mm. The simulated results for various characteristics of the antenna have been shown using flnite element technique based commercial software ANSOFT HFSS. The simulated and measured impedance results are in good agreement.

A LONG-RANGE COMPUTATIONAL RFID TAG FOR TEMPERATURE AND ACCELERATION SENSING APPLICATIONS

In this paper, the design, realization, and experimental validation of a battery-assisted radio frequency identiflcation (RFID) tag featuring sensing and computation capabilities are presented. The sensor-augmented RFID tag comprises an ultra-low-power microcontroller, temperature sensor, 3-axis accelerometer, non-volatile storage, and a new-generation I 2 C-RFID chip for communication with standard UHF EPCglobal Class-1 Generation-2 readers. A preliminary printed-circuit-board prototype, connected to a 3-V/225-mAh lithium battery, provides a lifetime up to approximately 3 years when sensing and RFID-based communication tasks are performed every 10 seconds. Moreover, the device exhibits indoor transmission ranges up to 22m, 6m, and 5m when attached to foam, concrete, and wood respectively. The encouraging results achieved for an emulated application scenario demonstrate the suitability of the device to be adopted in contexts where temperature and acceleration sensing are required.

COMPACT LOOP ANTENNA FOR NEAR-FIELD AND FAR-FIELD UHF RFID APPLICATIONS

A novel type of radio frequency identiflcation (RFID) reader antenna is proposed for mobile ultra-high frequency (UHF) RFID device. By folded-dipole loop structure with parasitic element, a small antenna size of 31⁄31⁄1:6mm 3 is achieved. The antenna with difierent parasitic element size can work on difierent UHF RFID bands. The antenna prototype is fabricated and the measured bandwidth is around 13.5MHz (915.5{929MHz), which covers the China RFID Band (920{925MHz). The measured reading distance achieves 65mm with the near-fleld RFID tag and 1.17m with the far-fleld tag. The measurement agrees well with simulated result and shows that antenna is desirable for both near-fleld and far-fleld UHF RFID applications.

PLATFORM-ROBUST PASSIVE UHF RFID TAGS: A CASE-STUDY IN ROBOTICS

The use of Radio Frequency IDentiflcation (RFID) technology in a large array of contexts is a matter of fact. In many cases, such as in robotic applications, the RFID tags should satisfy speciflc requisites so that read range, platform robustness, radiation properties, cost, and size must be properly taken into account during the design phase. In this work, the speciflc requirements of tags for RFID-assisted localization and navigation of mobile robots are highlighted and discussed. On such basis, an ad-hoc platform-robust RFID tag is designed, realized and exhaustively tested through both simulations and measurements. The achieved results are impressive and demonstrate the appropriateness of the proposed tag to operate in application scenarios where performance stability is mandatory.

DETERMINATION OF DIELECTRIC PROPERTY OF CONSTRUCTION MATERIAL PRODUCTS USING A NOVEL RFID SENSOR

This paper presents a concept, by which radio frequency (RF) tags are employed as remotely read dielectric-property sensors to determine qualities of some construction material products (CMPs); e.g., light weight concrete (LWC), mortar specimens and concrete. Using the dependency of the read range of the passive RF identiflcation (RFID) sensor system on the electromagnetic properties of CMPs near or in contact with RFID tags, the qualities of CMPs can be determined through their estimated dielectric properties. Theoretical formulation is provided, and numerical simulations are performed for optimal design of passive RFID tag antennas suitable for RFID sensors and for read-range calculations. In addition, a series of measurements is performed to measure read ranges of the passive RFID sensor system for an LWC as an example of CMPs, and these measured read ranges will be processed appropriately to inversely determine the dielectric constant of the LWC under test, which in turn provides information on its qualities. It is found that the novel RFID sensor can be employed to determine the dielectric properties of the LWC under test with reasonable accuracy.

AUTOMATED RFID-BASED IDENTIFICATION SYSTEM FOR STEEL COILS

This paper describes the radio frequency identiflcation (RFID)-based steel coil identiflcation system for supply chain management in the steel and iron industry. During crane operation, coil information is automatically updated by reading an RFID tag which is attached to the coil. One of the technical challenges associated with the RFID-based coil identiflcation is the fall of the identiflcation performance due to neighboring metallic objects. In order to cope with this problem, a system was developed in two directions. First, an efiective tag attachment method considering the work process and the environmental conditions was proposed. Second, an antenna case was developed to improve the reading performance by minimizing the in∞uence from the attached surface and focusing the RF signal to the target tag. The simulation and experimental results at the POSCO steel company verify that the proposed system can sense the target RFID tag successfully.

COMPACT DUAL BAND TAG ANTENNA DESIGN FOR RADIO FREQUENCY IDENTIFICATION (RFID) APPLICATION

The increasing need for automatic identiflcation and object tracking in supply chains has led to the development of radio frequency identiflcation (RFID) systems. High frequency (HF) and ultra-high frequency (UHF) bands are frequently used because of their advantages over other bands. Although many HF and UHF band tags exist, some are unsuitable to handle the hostile environment of a supply chain. Therefore, this paper contributes to the research on a dual band RFID tag antenna operating on both the HF (13.56MHz) and the UHF (919MHz to 923MHz) band, the UHF band used in Malaysia, by embracing the advantages of both HF and UHF bands to overcome the previously mentioned problems. The compact design is constructed by locating the UHF band antenna inside the HF band antenna and by reducing the number of turns of the HF band antenna compared to previous designs. The i10dB bandwidth for the proposed design covers 12.9MHz to 14.2MHz for the HF band and 914.0MHz to 929.0MHz for the UHF band. The proposed antenna also overcomes the degradation problem by obtaining a high e-ciency around 94% and a gain of 3.709dB.

A SRR-BASED NEAR FIELD RFID ANTENNA

In this paper, a compact near fleld reader antenna is proposed for ultra-high frequency (UHF) radio frequency identiflcation (RFID) applications. The antenna structure is composed of two split-ring-resonators (SRRs) and miniaturized to a special small size of 21 ⁄ 21 ⁄ 1:6mm 3 for mobile RFID application. The measured bandwidth of antenna prototype is 13MHz (914.5{927.5MHz) with re∞ection coe-cient less than i10dB, which covers the China RFID band II (920{925MHz). Simulation shows that the proposed antenna achieves a strong and uniform magnetic fleld distribution in the near fleld region, and the reading range is up to 42mm with near fleld RFID tag. Through modifying the parameters of SRRs, the antenna can operate on difierent UHF RFID bands (Europe band, China band I&II etc.).

COMPACT METAL MOUNTABLE UHF RFID TAG ON A BARIUM TITANATE BASED SUBSTRATE

The development of a compact metal mountable Radio- Frequency IDentiflcation (RFID) tag antenna on a ceramic substrate based on Barium Titanate is presented. The performance limitations and design trade-ofis of metal mountable RFID tag antennas are reviewed and the favorable features of a high-permittivity antenna substrate for the development of antennas for metal mountable RFID tags are discussed. The simulation-based tag antenna design process is outlined and the measured read range of the developed metal mountable tag on conductive platforms of various sizes is presented.

SMART PROTOTYPING TECHNIQUES FOR UHF RFID TAGS: ELECTROMAGNETIC CHARACTERIZATION AND COMPARISON WITH TRADITIONAL APPROACHES

Over the last few years, the active and growing interest in Radiofrequency Identiflcation (RFID) technology has stimulated a conspicuous research activity involving design and realization of passive label-type UHF RFID tags customized for speciflc applications. In most of the literature, presented and discussed tags are prototyped by using either rough-and-ready procedures or photolithography techniques on rigid Printed Circuit Boards. However, for several reasons, such approaches are not the most recommended, in particular they are rather time-consuming and, moreover, they give rise to low quality devices in one case, and to cumbersome and rigid tags in the other. In this work, two alternative prototyping techniques suitable for cost-efiective, time-saving and high-performance built-in-lab tags are introduced and discussed. The former is based on the joint use of ∞exible PCBs and solid ink printers. The latter makes use of a cutting plotter to precisely shape the tag antenna on thin copper sheets. Afterwards, a selection of tags, designed and manufactured by using both traditional and alternative techniques, is rigorously characterized from the electromagnetic point of view in terms of input impedance and whole tag sensitivity by means of appropriate measurement setups. Results are then compared, thus guiding the tag designer towards the most appropriate technique on the basis of speciflc needs.

A MULTI BAND MINI PRINTED OMNI DIRECTIONAL ANTENNA WITH V-SHAPED FOR RFID APPLICATIONS

This paper presents a mini multi-band printed omni- directional antenna with v-shaped structure for radio frequency identiflcation (RFID) applications. The proposed multi-band antenna is developed from the initial v-shaped design which is only capable of working as a single-band antenna. By deploying a concept of dipole antenna to an initial design, the proposed antenna is accomplished to operate with two difierent modes of RFID system which are passive and active modes at frequencies of 915MHz and 2.45GHz respectively. The passive RFID tag is invented when a chip of Ultra High Frequency (UHF) is integrated with a proposed multi-band antenna. This passive tag, which is able to radiate with the measured signal strength, shows that the reading ranges are boosted almost two times compared to the conventional inlay antenna. The maximum reading range of passive RFID tag with inlay antenna is 5m, though a reading range up to 10m is achievable through the deployment of the proposed antenna at a measurement fleld. Implicitly, the measurements carried out on the antenna are in good agreement with the simulated values. Moreover, the size of the mobile passive RFID tag has been substantially as 100mm £ 70mm, even though the antenna is fabricated with an inexpensive FR-4 substrate material. With the reasonable gain, coupled with cheaper material and smaller size, the proposed antenna

A COMPACT FRACTAL DIPOLE ANTENNA FOR 915MHz AND 2.4GHz RFID TAG APPLICATIONS

A compact printed dipole antenna using fractal shape for Radio Frequency IDentiflcation (RFID) is presented. The proposed antenna consists of a third iteration fractal tree structure with the aim of reducing the antenna size. It occupies a volume of 78£30£1:58mm 3 and the radiator is composed of two arms. The antenna has been designed and optimized to cover the bi-band for passive RFID tag at 915MHz and 2.4GHz. A parametric study of the proposed antenna was carried out in order to optimize the main parameters. Details of the proposed antenna design and measurement results are presented and discussed.

TIME-DOMAIN MEASUREMENT OF TIME-CODED UWB CHIPLESS RFID TAGS

Chipless ultra-wideband (UWB) has been proposed as a low-cost alternative for radiofrequency identiflcation (RFID). In this paper, a comprehensible theoretical introduction to time-domain operation of a UWB RFID tag is described, and a circuit model is proposed. For commercial applications low-cost RFID readers are demanded. To this end, this paper addresses the measurement of time-coded UWB chipless tags for RFID in time domain. Two difierent setups to detect time-coded tags are presented, one based on commercial UWB impulse radar (IR) and the other based on a vector network analyzer (VNA). The experimental results show the feasibility of using an IR-UWB radar as a UWB RFID reader, achieving very good read ranges.

Threshold Power-based Radiation Pattern Measurement of Passive UHF RFID Tags

This paper is concentrated on explaining threshold power-based radiation pattern measurement of passive ultra-high frequency (UHF) radio frequency identiflcation (RFID) tags. This measurement technique is wireless and the tag is measured in active state, i.e., in operation with the microchip. Information about the radiation pattern of an RFID tag is important in analyzing the strongest operation directions of the tag both in air and attached to identifled objects. In this paper we present examples of measured radiation patterns of a passive UHF RFID tag. 1. INTRODUCTION Measuring the radiation pattern of passive ultra-high frequency (UHF) radio frequency identiflca- tion (RFID) tags is challenging due to the special characteristics of RFID systems. Traditional antenna measurements where cables and matching circuits are attached to antennas are not recom- mendable because attaching cables afiects the properties of tag antennas. In addition, these kinds of measurements do not give proper information about the functioning of the tag. Therefore, novel and contactless radiation pattern measurement systems have been proposed to be used in RFID tag antenna radiation pattern measurement (1{3). In this paper, we will measure tag's radiation pattern with threshold-power based method in active mode, i.e., when the tag is characterized in operation with the microchip. Radiation pattern measurement of RFID tags is important in characterization of tag functioning. Similarly as the traditional antenna radiation pattern measurement, it gives information about the best radiation directions of the tag. More importantly, radiation pattern of a tag can be measured when the tag has been attached to the identifled object. This way the efiect of the identifled material on the radiation pattern of the tag can be verifled. Figure 1 presents the components of a passive UHF RFID system. The operation abilities of passive UHF RFID systems depend mainly on two fundamental operational principles of passive UHF tags (3): 1. The capability of the tag for wireless energy collection from the reader, i.e., tag's energy harvesting. This depends on the impedance matching between the tag's antenna and the microchip and the microchip's sensitivity. The energy harvesting information provides factors that deflne a minimum transmission power level for the reader unit to turn the tag on over a certain reading distance, i.e., tag's threshold power. 2. The strength and clarity of desired backscattered signal from the tag, i.e., the radar cross section (RCS) properties of the tag.

PLANAR ANTENNAS FOR PASSIVE UHF RFID TAG

In this paper, design, fabrication, and testing of Radio Frequency Identiflcation (RFID) antennas for the European Telecom- munications Standards Institute (ETSI) and Federal Communications Commission (FCC) bands are discussed. The designs proposed in this paper are for UHF RFID tag that conforms to EPCglobal C1G2 1.2.0. The exceptional characteristics of the RFID are investigated in terms of antenna-IC matching and radiation e-ciency. The proposed RFID antennas have been fabricated on 5 mil thick Flexible Copper Clad Laminate and the read range of the proposed RFID antennas is exper- imentally tested. Measured free air read range of all proposed designs is over 4m. The performance of the tag antenna design a-xed to var- ious objects is also tested with read range measurements. The results show that the antenna designs can be used for tagging cardboard and plastic objects.