A Miniature Antenna for 2.45 GHz RFID Tag

Abstract

On the basic of fractal theory and folded technique, a miniature antenna for 2.45 GHz radio frequency identification (RFID) tag applications is designed and analyzed in the present paper. In order to realize the miniaturization of tag antenna, a Hilbert fractal structure is used. Impedance matching between antenna and IC chip is of great importance for improving tag performances. A folded technique is employed to achieve impedance matching flexibly. The value of input impedance of tag antenna can be varied readily only by tuning the high of folded line. The dimensions for the designed tag antenna at 2.45GHz are 23.32mm×7.66mm, and its return loss, bandwidth, and gain are analyzed by HFSS. The detection distance is estimated by Friis transfer theory. Analysis results demonstrate that the tag antenna designed in this paper may satisfy the requirements of RFID tag applications.

Microstrip back-cavity Hilbert Fractal Antenna for experimental detection of breast tumors

“…electrical permittivity and conductivity at 2.45 GHz [9][10][11][12] and thicknesses experienced in average for each tissue layer. Due to its compactness, a Hilbert Fractal Antenna (HFA) is chosen for the initial antenna design [13]. The antenna dimensions and shape are optimized using CST microwave studio software.…”

Miniature antenna for breast tumor detection

“…An HFA (Hilbert Fractal Antenna) for RFID (Radio Frequency Identification) tag applications is chosen for the basic antenna design [9]. Thanks to the compact shape of this antenna that makes it possible to investigate tumors in a relatively small area of the women's body.…”

“…Phantom breast model.The electrical characteristics (electrical permittivity and conductivity) for the different tissues of the phantom breast up to 2.45 GHz are given in table II[8][9][10][11].…”