Conformal Magnetic Composite RFID for Wearable RF and Bio-Monitoring Applications

©2008 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or distribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.10.1109/TMTT.2008.2006810This paper introduces for the first time a novel flexible magnetic composite material for RF identification (RFID) and wearable RF antennas. First, one conformal RFID tag working at 480 MHz is designed and fabricated as a benchmarking prototype and the miniaturization concept is verified. Then, the impact of the material is thoroughly investigated using a hybrid method involving electromagnetic and statistical tools. Two separate statistical experiments are performed, one for the analysis of the impact of the relative permittivity and permeability of the proposed material and the other for the evaluation of the impact of the dielectric and magnetic loss on the antenna performance. Finally, the effect of the bending of the antenna is investigated, both on the S-parameters and on the radiation pattern. The successful implementation of the flexible magnetic composite material enables the significant miniaturization of RF passives and antennas in UHF frequency bands, especially when conformal modules that can be easily fine-tuned are required in critical biomedical and pharmaceutical applications

Characteristics of a Linearly Tapered Slot Antenna (LTSA) Conformed Longitudinally Around a Cylinder

The family of tapered slot antennas (TSA s) is suitable for numerous applications. Their ease of fabrication, wide bandwidth, and high gain make them desirable for military and commercial systems. Fabrication on thin, flexible substrates allows the TSA to be conformed over a given body, such as an aircraft wing or a piece of clothing for wearable networks. Previously, a Double Exponentially Tapered Slot Antenna (DETSA) was conformed around an exponential curvature, which showed that the main beam skewed towards the direction of curvature. This paper presents a Linearly Tapered Slot Antenna (LTSA) conformed longitudinally around a cylinder. Measured and simulated radiation patterns and the direction of maximum H co-polarization (Hco) as a function of the cylinder radius are presented

3-D-Printing-Based Selective-Ink-Deposition Technique Enabling Complex Antenna and RF Structures for 5G Applications up to 6 GHz

This paper introduces a novel additive-manufacturing technique to obtain high-resolution selective-ink-deposition on complex 3-D objects, packages, and modules for 5G applications. The technique consists of embossing the desired pattern directly on the 3-D printed dielectric surface and then applying ink with a suitable tool. This approach is tested in combination with stereolithography 3-D printing technology to obtain selectively metallized 3-D circuits. In particular, the "clear" resin from FormLab is utilized for the 3-D printed dielectric, while the metallization is performed with silver nanoparticle ink from Suntronic. As a preliminary study, test samples containing lines with different widths are manufactured, demonstrating a pitch down to $135~\mu \text {m}$ and satisfactory sheet resistance of $0.011~\Omega /\text {sq.}$ (the electromagnetic characterization of the dielectric resin is reported in the Appendix). Then, two broadband multiport RF structures are developed to show the versatility of the proposed technology. First, an ultrawideband 3-D crossover, operating in the range 100 MHz–5 GHz, is conceived to test the suitability of the proposed technology to perform selective metallization on curved semienclosed areas. Then, the technology is applied to a multiple-input–multiple-output (MIMO) antenna system, based on four proximity-fed annular slot antennas, arranged on the lateral sides of a cube and decoupled by introducing a cross-shaped structure in the interior of the cube. This circuit offers a broad range of metallization challenges, as it features embossed and engraved parts, high-resolution patterns (line widths down to 0.7 mm) and sharp edges. Each slot radiates unidirectionally with the same polarization and uses the cube and its internal cross-shaped structure as a resonant cavity. The antenna system is designed to operate in the band 3.4–3.8 GHz, which is one of the sub-6-GHz 5G bands in Europe, and it is thought for hotspot and access-point applications. The final antenna topology is composed of only two blocks, weighs 21.29 g, and occupies a volume of $44.4\times 45.8\times 45.8\,\,\text {mm}^{3}$ , featuring an envelope correlation coefficient (ECC) lower than 0.005 and a total active reflection coefficient (TARC) lower than −6 dB in all the bands of interests

Inkjet‐/3D‐Printed Paper/Polymer‐Based "Green" RFID and Wireless Sensor Nodes: The Final Step to Bridge Cognitive Intelligence

Presented at the Nano@Tech Meeting on January 12, 2016 at 12:00 p.m. in room 1116-1118 of the Marcus Nanotechnology Building on the Georgia Tech campus.Manos M. Tentzeris received the Diploma (magna cum laude) degree in electrical and computer engineering from the National Technical University of Athens and the M.S. and Ph.D. degrees in electrical engineering and computer science from the University of Michigan. He has helped develop academic programs in highly integrated/multilayer packaging for RF and wire- less applications using ceramic and organic flexible materials, paper-based RFIDs and sensors, biosensors, wearable electronics, inkjet-printed electronics, green electronics and power scavenging, nanotechnology applications in RF, microwave MEM's, and SOP-integrated (UWB, multiband, millimeter wave, and conformal) antennas, and heads the ATHENA Research Group. He has been a Visiting Professor at the Technical University of Munich, GTRl-lreland, and LAAS-CNRS in Toulouse, France. He has served as the Head of the GT-ECE Electromagnetics Technical Interest Group, as the Georgia Electronic Design Center Associate Director for RF ID/Sensors Research, and as the Georgia Tech NSF-Packaging Research Center Associate Director for RF Research and the RF Alliance Leader. He is currently a Professor with the School of ECE at Georgia Tech. He has given more than 100 invited talks to various universities and companies all over the world and has published more than 580 papers in refereed journals and conference proceedings, five books, and 21 book chapters. He is the recipient of numerous awards, most recently the 2015 IET Microwaves, Antennas and Propagation Premium Award and the 2014 Georgia Tech ECE Distinguished Faculty Achievement Award.Runtime: 53:29 minutesIn this talk, inkjet-printed flexible antennas, RF electronics and sensors fabricated on paper and other polymer (e.g.LCP) substrates are introduced as a system-level solution for ultra-low-cost mass production of UHF Radio Frequency Identification (RFID) Tags and Wireless Sensor Nodes (WSN) in an approach that could be easily extended to other microwave and wireless applications. The talk will cover examples from UHF up to the millimeter-wave frequency ranges. A compact inkjet-printed UHF "passive-RFID" antenna using the classic T-match approach and designed to match IC's complex impedance, is presented as a the first demonstrating prototype for this technology. Then, Prof. Tentzeris will briefly touch up the state-of-the-art area of fully-integrated wireless sensor modules on paper or flexible LCP and show the first ever 20 sensor integration with an RFID tag module on paper, as well as numerous 30 multilayer paper-based and LCP-based RF/microwave structures, that could potentially set the foundation for the truly convergent wireless sensor ad-hoc networks of the future with enhanced cognitive intelligence and "rugged" packaging. Prof. Tentzeris will discuss issues concerning the power sources of "near-perpetual" RF modules, including flexible minaturized batteries as well as power-scavenging approaches involving thermal, EM, vibration and solar energy forms. The final step of the presentation will involve examples from wearable (e.g. biomonitoring) antennas and RF modules, as well as the first examples of the integration of inkjet-printed nanotechnology-based (e.g.CNT) sensors on paper and organic substrates. It has to be noted that the talk will review and present challenges for inkjet-printed organic active and nonlinear devices as well as future directions in the area of environmentally-friendly ("green") RF electronics and "smart-skin' conformal sensors

Liquid RF Antennas, Electronics and Sensors: A Modeling Challenge

Abstract In this paper we present a novel approach for the modeling of multi-phase liquid RF electronics and sensors problems. The deployment of level-set based multi-phase simulation could potentially lead to the development of a new generation of computationally efficient approaches that could bridge the gap between Maxwell and solid/liquidinterface equations. Numerous examples of liquid antennas and multi-phase wireless biosensors will be presented at the conference to verify the accuracy and validity of the above approach in a variety of liquid radio-frequency wearable, implantable and printable topologies