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In this article, we present the design and realization of an electronically rewritable RF encoding particle (REP) for chipless RFID applications. This (REP) resonator geometry is integrated with two conductive bridging random access memory (CBRAM) based non-volatile RF switches, and could be electronically programmed using DC pulses to any of possible four resonant states to represent two bits of information. Emerging additive manufacturing (AM) technique based thermal transfer printing is utilized for the realization of this resonator on flexible and low cost Polyethylene terephthalate (PET) substrate. At present the size of the REP is such that five such REPs could be arranged on a standard credit card size tag. Also this REP encodes the most number of bits reported among non-volatile electronically rewritable REPs for chipless RFID applications - 2 bits, till date.

We report the design of a passive UHF RFID sensor compliant with the EPC Gen2 standard for tilt and temperature monitoring of fragile objects during transportation. The solution is based on the combination of a Farsens Rocky100 IC and a 3-axis accelerometer ADXL362 IC embedding a temperature sensor. The design is validated by simulation, measurement of the reading performance with a dedicated bench, and test of the RFID sensor in practical situations.

International audience; This study reports the design and experimental results of a fully-passive solid-state RF switch based on the Conductive Bridging Memory Technology, popularly known as CBRAM. The developed device is a shunt mode RF switch based on a Metal-Insulator-Metal (MIM) structure with Copper-Nafion-Aluminum switching layers on a Coplanar Waveguide (CPW) transmission line, operational in the DC to 3GHz range. DC pulses in the range +12V to-20V are used to operate the switch. The design is initially simulated using the FEM based CST microwave Studio and then realized and validated on a low cost FR4 substrate, and without using any sophisticated clean room technology.

A low-cost passive UHF RFID tag-based sensor is presented. The proposed tag-based sensor comprises a dual-feed patch antenna incorporated with passive sensor and passive RFID chips operating at UHF RFID bands. By introducing the passive sensor (i.e. resistive sensor nodes) in one of the tag antenna feed, low-cost wireless nodes with radio frequency identification and sensing capabilities are implemented. To remotely record the sensed data at any arbitrary distance from the reader, the other feed of the tag antenna is incorporated with only RFID chip and it serves as a reference node. By measuring the difference of the required minimum power transmitted by the reader to wake-up the RFID chips in both the reference and sensor nodes, the reader then can extract the sensed data (i.e. temperature) at the tag location.

In this paper we focus on the design of a miniaturized implantable RFID sensor to enable remote identification and sensing for orthopedic prosthesis dedicated to hips and knees. The current issues to overcome in the world of orthopedic surgery are a better tracking of patient's implants integrity during the whole cycle life of the prosthesis. Second, in case the prosthesis should be changed, it would be interesting to have a clear picture of the prosthesis model before the surgical operation to be sure that no surprise arises during the operation. The RFID is a technology which can perfectly match these required key points. A passive RFID tag doesn't need any local battery supply since it harvests energy from the electromagnetic (EM) field of the reader. In its simplest form it is composed of an antenna connected to a chip. The technology involved is shared mainly between HF technologies based on near field communication principle, and UHF technology (867 MHz in Europe). In this paper we study the possibility to design an implant based on UHF RFID tag. Even though, the wireless link losses are higher in human body tissues, the main interest to compare with HF RFID is the higher read range capability (up to several meters) which is more compatible with the aforementioned application for which a detection distance of 50 cm is needed. In order to sense if the prosthesis is properly inserted within the bone, and if it doesn't show any tilt, a pressure sensor is attached to the dedicated RFID IC SL900A from AMS with no additional components as shown in Fig. 1 (a). In order to miniaturize the implant, a ceramic chip antenna operating around 900 MHz is connected to the AMS IC (see Fig. 1 (b)). The whole assembly made of the pressure sensor, the IC and the antenna is coated with PDMS silicon-based resin. This makes a flexible 20×20mm2 RFID-enabled sensor operating at a distance in free space up to 0.6 meter in passive mode as shown in Fig. 1 (c).

Nowadays, flexible electronics is a challenging research area cause of the increase of electronics component request for “the internet of things”, the food safety and the medical diagnostic applications. In our research, we work with an unusual substrate for microtechnologies such as paper, which is flexible, brittle, and biodegradable. Also, it can be folded, cut, perforated, crumpled, etc. This article focuses on monitoring porous Anodic Aluminum Oxide (AAO) layer on paper-based substrate for the detection of humidity. Porous AAO is a material with cylindrical pore geometry and high aspect ratio. Further, this material has many advantages, such as, easy fabrication, pore diameter's uniformity with high pore density (1011/cm2) and its use like humidity sensors. In summary, the AAO process fabrication on paper substrate is challenging causes of his ease of implementation, cost-effective and the use of a highly economical, conformable and ecological substrate. In this study, an experimental setup had been developed to anodize an aluminum layer deposit on flexible substrate by using phosphoric acid. Various anodization parameters (voltage, current density, temperature and concentration) have been investigated to obtain an AAO layer with good electrical properties and high reliability on flexible substrate. An interdigital capacitance has been deposited on the best AAO layer produced to fabricate a moisture sensor. The different sensors produced had been characterized versus humidity concentration and frequency in a climatic chamber. Depending on the AAO morphology parameters, the average sensitivity can be tuned from 0.8 pF/RH% to 9 pF/RH%.