International audienceIncreasing the coding capacity of chipless RFID tags is a key factor while considering the development of miniaturized tags. A novel hybrid coding technique by combining phase deviation and frequency position encoding is proposed here. A coding capacity of 22.9 bits is obtained simply with five resonators within a reduced dimension of 2 cm × 4 cm. The proposed tag is based on 5 'C' like metallic strip resonators having resonance frequency within the band of 2.5 GHz to 7.5 GHz. The tag is potentially low-cost since only one conductive layer is needed for the fabrication. Different tag configurations are designed and validated with measurement results in bi-static configuration. A good agreement between measurement and simulation validates the theoretical predictions

International audienceThis 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

International audienceDesigning 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

Abstract-A compact printed and planar Multiple-Input MultipleOutput (MIMO) for Ultra Wideband (UWB) communications is presented. Two circular disc monopole antenna elements constitute the proposed UWB-MIMO antenna operating over the frequency band of 3.2-10.6 GHz. The isolation between the antenna ports has been enhanced to the value of more than 15 dB throughout the frequency band of interest. This enhancement is achieved by taking the advantage of an inverted-Y shaped stub that is being inserted on the ground plane of UWB-MIMO antenna. The insertion of the stub has also facilitated reduction of the size of the antenna, i.e., overall dimensions of the antenna are 40 × 68 mm 2 . The proposed antenna is investigated both numerically and experimentally.

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International audienceThis 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

International audienceIn 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

International audienceEntering "RFID" on your Web browser will return you more than 50 million links. This huge number of references is a result of the impact of radio-frequency identification (RFID) technology worldwide [1]. Indeed, RFID technology is exploited in numerous domains, with thousands of applications, including more and more seen in everyday life. The RFID market is worth several billion dollars today, and its growth is more than 10% per year [2], [3]. There are two main classes of RFID devices. Figure 1 illustrates the main features of each class. The most known and broadly used class is the one based on the use of an integrated circuit (IC) chip in which the information is stored and that is connected to an antenna; the two together form the "tag." Such a technology exhibits several advantages, including flexibility and versatility in terms of the application. Nevertheless, it has some drawbacks mostly in terms of cost, robustness, reliability, data security, and poor recyclability of tags. More properties and new functionalities, such as sensing capabilities and tag-totag communication [4], are continually being developed, leading to the new paradigm of Internet of Things [5]