RFID Double-Loop Tags with Novel Meandering Lines Design for Health Monitoring Application

Ibtissame Bouhassoune,Rachid Saadane,Khalid Minaoui

doi:10.1155/2019/5076139

Ibtissame Bouhassoune, Rachid Saadane + Show 1 more

Open Access

https://doi.org/10.1155/2019/5076139

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Abstract

In this paper, we propose a design of two compact and miniaturized RFID epidermal tags in the UHF band for health monitoring applications. The two conceptions of meandered double-loop antennas with T-match configuration, namely, a double-loop antenna with meandered line in the horizontal direction and a double-loop antenna with meandered lines in two directions, are placed at very close distance from the human body. The proposed tags are composed of bio-silicone substrate, to protect the human skin from the electromagnetic waves, and a copper conductor loaded by T-match configuration, to suit the complex impedance of the antenna to that of the chip. We have performed numerical simulations of these conceptions of two tags using the HFSS and CST solvers. Our results show two optimal sizes with a high communication performance, good matching features, and a large read range. We placed afterwards these two optimized tags in an elliptical environment to test their flexibility and examine their performance on different parts of the human body.

Highlights

E radiofrequency identification (RFID) system is composed of remote tags and interrogators or readers devices. e former has the potentiality to properly collect the energy from the readers and store the data in the microchip, while the latter transmit and receive the radio waves to communicate with tags [1]
E epidermal RFID tags are placed in direct touch with human skin, and fabricated with a very thin, flexible, and biocompatible material, acting as an insulator between the conductor/electronic components and the skin
The cohabitation of passive tag elements with the human skin represents a complex challenge due to high losses in human tissues which strongly affect the general properties of the antenna. e electromagnetic waves emitted by the reader are either reflected or absorbed by the human tissue, and the performance of the wireless communication diminishes [3]

Summary

Introduction

One of the most striking evolutions of radiofrequency identification (RFID) is manifested in the epidermal RFID family for human health monitoring applications and indoor/outdoor tracking systems. is new RFID technology plays two roles, the first one is to identify different objects, and the second one is to sense physiological parameters of the human body (temperature, pressure, heartbeat, etc.). Some successful works in the healthcare technology have extended the epidermal RFID systems to the UHF band (840–960 MHz). They are highly influenced by high dielectric objects as the human skin, but in principle, they can provide a long activation distance range. Various developments in the UHF RFID technology for human monitoring applications presented so far are interested to the innovative biosensor/tag with miniaturized size, reduced cost for wearable applications, like a famous slotted patch tag combined with a motion sensor, or fabricated with textile materials, which permits to decouple the antenna from the lossy human tissues [5, 6], and double T-slotted patch designed for wristbands applications [7].

Electromagnetic Equations for UHF RFID Technology

Antennas Conception

Matching Features and Radiation Performances of the