A. Ali Babar

Small and Flexible Metal Mountable Passive UHF RFID Tag on High-Dielectric Polymer-Ceramic Composite Substrate

A small and flexible metal mountable UHF RFID tag antenna, utilizing a high-permittivity substrate material is presented. The tag is composed of a small single-layer T-matched dipole antenna, on a flexible ceramic (BaTiO3) polymer (polydimethylsiloxane) composite substrate, with a thickness of 1.5 mm. The flexibility of the substrate allows it to be mounted on flat and cylindrical metallic surfaces. The performance of the developed tag is evaluated through simulations and measurements on both flat and cylindrical metallic platforms of various sizes. The results show that the tag achieves state-of-the-art size-performance ratio while meeting the key requirements of an affordable RFID tag with a simple and flexible structure.

Fabrication of embroidered UHF RFID tags

A laboratory-fabrication of embroidered antennas for ultra high frequency (UHF) radio frequency identification (RFID) tags is presented. The embroidered antenna patterns are formed from conductive thread using software controlled embroidery machine. Measurements of fully assembled embroidered UHF RFID tag verify that competitive tag performance can be achieved with the presented fabrication method.

Inkjet-printable UHF RFID tag antenna on a flexible ceramic- polymer composite substrate

The utilization of inkjet-printing technique to develop a printable UHF RFID tag antenna on flexible ceramic-polymer composite material is demonstrated. The substrate material is fabricated using high permittivity Barium Titanate (BaTiO3) ceramic powder mixed with polydimethylsiloxane (PDMS) polymer. A UHF RFID tag antenna is inkjet-printed using silver nano-particle to exploit the potential advantages of high dielectric flexible composite material when used as a tag substrate. Our preliminary results yielded a small flexible UHF RFID tag antenna with read range comparable to commercially available tag antennas.

Practical read range evaluation of wearable embroidered UHF RFID tag

In this study, the on-body read range performance of a wearable ultra-high frequency (UHF) radio frequency identification (RFID) tag is evaluated. The tag is fabricated using conductive thread and an embroidery machine. A measurement scenario is described, in which such an embroidered tag is attached to human clothing. The measurement results demonstrate the practical read ranges of the tag utilizing the new concept of using conductive threads. A maximum read range of 1.30 meters is attained.

RFID Tags for Challenging Environments: Flexible High-Dielectric Materials and Ink-Jet Printing Technology for Compact Platform Tolerant RFID Tags

In the rapidly evolving world of innovations and development, there is a growing need to have efficient and reliable communication systems. Wireless communication has gained great importance in recent years [1]. It has enabled the development of new wireless technologies such as auto-identification, mobile communications, global positioning, satellite, and other digital communication systems for various walks of life [2]. One of the most distinct parts of a wireless device is its radio unit or transmit/receive unit. The antenna in a radio unit plays an important role in achieving a high-performance wireless system. There are several design challenges and environmental factors that limit and affect the performance of an antenna and hence the performance of a communication system [3], [4]. Advanced new techniques are required to improve the performance and reliability of communications systems.

Performance of RFID bowtie tag antenna with different impedance matching

In this paper the performance of passive UHF RFID bow tie tag with different impedance matching was analyzed by simulation and measurement. Tag antenna design differs from conventional antennas. In tag design, when the PRC of tag is up to -7 dB or -8dB, it can be considered as good tag and even as low as -5 dB PRC is sufficient for several application. However, Co-Design is recommended for the application specific solutions to ensure proper operation of RFID tags and avoid unnecessary lost of performance.

Washing durability of embroidered polymer coated RFID tags

Embroidered RFID tags can be used in fabric integrated on-body applications such as tracking and access control. Moreover, embroidered antennas are important also in other wearable, body-centric wireless systems. The durability of the embroidered tag antenna is essential for garment-integrated applications due to the high probability to encounter different environmental conditions. In this paper, the effect of washing on an embroidered RFID tag with a polydimethylsiloxane (PDMS) polymer coating is investigated by measuring the realized gain of the antenna before and after each washing procedure. It was found that coating the embroidered tag antenna with a polymer increased its washing durability.

A novel wireless inkjet-printed chipless sensor for moisture detection utilizing carbon nanotube

A new chipless sensor for water droplet detection is proposed. This concept is demonstrated by inkjet-printing a dual rhombic loop scatterer on a flexible substrate having a size of 4×2cm2 only. This sensor operates in the ISM band at 2.45 GHz. The scatterer is doped with a thin layer of carbon nanotube-based organic ink to enhance its sensitivity in the presence of water. Strong water molecule adsorption by the carbon nanotubes helps to detect and record when a water drop has been in contact with the sensor. The sensors electromagnetic response is modified permanently so that a “water event” can be detected later. Simulation and wireless measurement results validate this new concept.

Exploiting the characteristics of paraffin as a substrate for UHF RFID and antenna applications

In this paper, the characteristics and possible applications of a new antenna substrate material which is developed using paraffin wax is discussed. The substrate is a low loss material and helps to achieve high performance antennas for various applications. This type of low cost substrate material can be molded into different shapes and forms. They can be used as antenna substrate materials in various cold storage and room temperature environments, for prototyping and several other applications. They can also be useful in designing heat sensing RFID tag antennas, due to the change in the dielectric properties of paraffin in high temperature environments. The results demonstrate the performance of the UHF planar antenna and an RFID tag fabricated on the new substrate.