Arnaud Vena

High-Capacity Chipless RFID Tag Insensitive to the Polarization

Designing a reader for chipless RFID is a hard task since both the polarization and operating frequency agility have to be implemented. The new tag design proposed in this paper is polarization independent, making the design of the reader easier since only linear polarization is needed to detect the tag. The proposed chipless tag is based on multiple circular ring patch resonators. The coding capacity of this tag reaches 19 bits within a compact surface of cm . Further, the frequency band is within 3.1 to 10.6 GHz to be compliant with FCC and ECC regulations for UWB. This new design is experimentally validated in the frequency domain using bi-static measurement set-up. Both amplitude and group delay responses of the tag are investigated and carried out.

A Depolarizing Chipless RFID Tag for Robust Detection and Its FCC Compliant UWB Reading System

A new chipless RF identification (RFID) tag design is presented in this paper to ease the detection of items in a real environment. For this purpose, we present multiple scatterers able to depolarize the incident wave to create a response in the orthogonal polarization. Measurements in anechoic chamber and in a real environment, when the tags are positioned on dielectric and metal objects, show their higher detection capability. For the first time, a study on the technique to increase the detection area with a simplified calibration step is carried out. This makes possible the detection of the tag on objects of various sizes and compositions, which is required in the majority of RFID applications.

Design of Compact and Auto-Compensated Single-Layer Chipless RFID Tag

This paper presents a new radio frequency identification (RFID) chipless tag that is highly compact and potentially low-cost. This tag has a lot of advantages, such as being fully printable on products since no ground plane is needed for fabrication. The actual issue of the chipless tag family having a single layer, that is, their detuning effect, is compensated for the first time by a correction technique based on the use of a sensing resonator. The design is based on multiple λ/4 coplanar strip-line resonators where resonant frequencies can be shifted by setting an additional short circuit at particular locations. An accurate model is proposed to easily link the footprint of the structure to the resonant frequency. Considering a frequency resolution of 50 MHz for the reading system and a tag dimension of 15 × 20 mm2, 9 b can be encoded in the frequency band 2.0-5.5 GHz. Several experimental results validate the proposed design as well as its implementation in a realistic application and environment.

A Fully Printable Chipless RFID Tag With Detuning Correction Technique

This article presents a new chipless RFID tag operating in the frequency span 2 to 4 GHz. In particular the tag does not require any ground plane and it is made of 20 scatterers giving 20 b as coding capacity, for a compact size of 70 25 , compatible with a credit-card format. Its fabrication process is potentially very cheap because it needs only one conductive layer, so that it can be fully printed directly on the product. To overcome the detuning effect inherent to a single layer tag and make this design robust to the environment versatility, a simple compensation technique is introduced and experimented for the first time. Measurements have been performed frequency domain, using amplitude and the group delay response. The exploitation of group delay appears to be very reliable and promising way to retrieve the coded information.

Design of Chipless RFID Tags Printed on Paper by Flexography

In this paper, we demonstrate for the first time that a 19-bit chipless tag based on a paper substrate can be realized using the flexography technique, which is an industrial high-speed printing process. The chipless tag is able to operate within the ultra-wide band (UWB) and has a reasonable size ( 7×3 cm 2) compared to state-of-the-art versions. Thus, it is possible to use this design for various identification applications that require a low unit cost of tags. Both the simulation and measurement results are shown, and performance comparisons are provided between several realization processes, such as classical chemical etching, flexography printing, and catalyst inkjet printing.

Design and Implementation of Electro-Textile Ground Planes for Wearable UHF RFID Patch Tag Antennas

Localization, wireless monitoring, and emerging body-centric wireless systems demand low-cost and low-power devices that are efficient, maintenance-free, and comfortable to wear. Patch-type UHF radio frequency identification (RFID) tag antennas realized using electro-textiles are promising candidates for this purpose. In this letter, we design a patch-type tag antenna operating at 900 MHz and investigate how different types of ground planes using electro-textiles affect the antenna performance. Various conductive fabrics and embroidery structures are considered. We demonstrate that depending on the ground plane structure and density, it is possible to influence the tag impedance behavior and radiation characteristics. Furthermore, wireless reflectometry measurements are conducted to characterize the sheet resistance for the investigated electro-textiles. We then use the sheet resistance in modeling the conductive fabric ground planes in a full-wave electromagnetic solver. Our results contribute to deeper understanding of the complex electro-textiles structures and guidelines for future practical wearable antenna designs.

A Fully Inkjet-Printed Wireless and Chipless Sensor for CO 2 and Temperature Detection

A study on a low-cost wireless fully inkjet-printed chipless sensor on a flexible laminate with three different inks is presented. It is based on two split ring resonator 90° oriented between each other to allow for independent responses on two polarizations. A deposit of a polymer/single walled carbon nanotube composite ink is used to allow for the detection of CO2 as well as temperature. In this paper, it is shown that the inkjet printing of a polymer-based coating on top of the sensing/reactive deposit can significantly reduce the sensitivity to CO2, whereas the temperature sensitivity stays at same. Simulations and experimental results verify the repeatability of this topology.

A compact chipless RFID tag using polarization diversity for encoding and sensing

The chipless RFID tag presented exploits the advantage offered by polarization diversity to encode more information within a given surface size. It is based on 3 split ring resonators with variable gap configuration. Depending on the used linear polarization, different resonant modes can be measured for the same resonator so that the coding capacity is increased. Since the used structure is very sensitive to polarization angle, this interesting behavior can be used to detect a rotation angle of an item with 20° of accuracy. On the other hand, contrary to most of chipless tags that need UWB operating frequencies, the proposed tag is based on diversity polarization and only narrow frequency bands are needed. Using only 3 resonant frequencies in the 3.4 GHz to 7.1 GHz band, a capacity of coding of 6 bits is reached within a tag of size 3×3 cm2. Measurements done using a bi-static radar configuration in the frequency domain validate this new concept.

Implementation of a Dual-Interrogation-Mode Embroidered RFID-Enabled Strain Sensor

This letter studies a dual-interrogation-mode (hybrid chip-enabled/chipless) technique to detect an embroidered radio frequency identification (RFID)-enabled sensor. We have created a hybrid RFID strain sensor utilizing both chipped and chipless approaches. A comparison between the read-range extraction technique, which relies upon the detection of the threshold power that is required to activate an RFID IC, and a radar-cross-section (RCS)-based technique that does not require any protocol is presented. An embroidered RFID sensor with an electrical length that is directly linked to the applied strain is realized and interrogated using both techniques. The sensitivities for the chipless radar technique and for the chip-enabled read range extraction technique are 0.66% and 0.43% frequency shift, respectively, for 1% strain variation. Simulations and measurements validate the dual interrogation mode and provide the proof of concept that a chip-enabled RFID sensor tag can be detected accurately utilizing backscattering RCS measurements.

A compact chipless RFID tag with environment sensing capability

This paper presents a chipless RFID tag having both identification and sensing capability. It is based on 5 resonant scatterers that behave as signal processing antennas in the band from 2.5 to 7.5 GHz. Only one scatterer is used to monitor a physical parameter variation, while the four others allow identifying the remote sensor with 13 bits. To make a resonator sensitive to the temperature or humidity, a material based on Silicon Nanowire is deposited on the tag surface using a very simple process. The tag needs only one conductive layer so that it can be directly printed on product making by the way a unit cost potentially very low. Measurements done using a bi static radar configuration in the frequency domain validate this new concept.