Advanced Carbon-Fiber Composite Materials for RFID Tag Antenna Applications

In this paper we explore the use of carbon fiber composites (CFC) in radio-frequency identification (RFID) antenna applications both numerically and experimentally. For this purpose, we use two kinds of CFC materials as the radiating element. We consider two types of RFID antennas: the T-match bowtie antenna, and the meander line antenna. The electromagnetic (EM) model of CFC antennas is developed using the Microwave Studio software for numerical analysis. By characterizing samples of CFC material an accurate model of the composite is obtained to be used in the antenna simulation. The composite RFID antenna performance is investigated and compared with a metal antenna. The performance of the antenna can be controlled using the anisotropic property of reinforced continuous carbon fiber composite material. The bandwidth, radiation resistance, and gain/read-range of the RFID antenna can be adjusted by changing the thickness, conductivity, and fiber orientation of the composite material. Because the CFC antenna has a much higher bandwidth, it can be more effective than a metal antenna in RFID.