This paper presents a one-wavelength loop antenna fed by an inductively coupled loop for on-body applications. An equivalent circuit for the inductively coupled loop antenna is proposed to synthesize the antenna system with a microchip. The designed tag is printed on a PVC substrate and placed close to a four-layer stratified elliptical cylinder human model. The card-type tag measures 85.5 × 54 × 0.76 mm3 and is suitable for use on a student ID card for a broad range of applications. The impedance bandwidth of the inductively coupled loop tag antenna is 60 MHz (880-940 MHz, 6.6%), which covers the operating UHF bands in U.S. and Taiwan. The measured reading distance ranges from 2.7 to 5.7 meters when placed at different positions on the chest of a human body in the open site.
"Inductively Coupled Loop Antenna Design for UHF RFID on-Body Applications," Progress In Electromagnetics Research,
Vol. 143, 315-330, 2013. doi:10.2528/PIER13080707
1. Finkenzeller, K., RFID Handbook: Fundamentals and Applications in Contactless Smart Cards and Identification, 2nd Ed., Wiley and Sons, 2003.
2. Lin, M. H. and C. W. Chiu, "Human-body effects on the design of card-type UHF RFID tag antennas," Proc. IEEE Symposium on Antennas and Propagation, 521-524, 2011.
3. Marrocco, G., "RFID antennas for the UHF remote monitoring of human subjects," IEEE Transactions on Antennas and Propagation, Vol. 55, No. 6, 1862-1870, Jun. 2007. doi:10.1109/TAP.2007.898626
4. Occhiuzzi, C., S. Cippitelli, and G. Marrocco, "Modeling, design and experimentation of wearable RFID sensor tag, ," IEEE Transactions on Antennas and Propagation, Vol. 58, No. 8, 2490-2498, Aug. 2010. doi:10.1109/TAP.2010.2050435
5. Rajagonpalan, H. and Y. Rahmat-Samii, "On-body RFID tag design for human monitoring applications," Proc. IEEE Symposium on Antennas and Propagation, 11-17, Jul. 2010.
6. Chiu, C. W., C. A. Ou, H. C. Wang, and Y. C. Chuang, "Slot antenna for UHF RFID tag close to the chest of a human body," Microwave and Optical Technology Letters, Vol. 53, No. 7, 1626-1631, Jul. 2013. doi:10.1002/mop.27610
7. Chen, W. T. and H. R. Chuang, "Numerical computation of human interaction with arbitrarily oriented superquadric loop antennas in personal communications," IEEE Transactions on Antennas and Propagation, Vol. 46, No. 6, 821-828, Jun. 1998. doi:10.1109/8.686768
8. Im, Y. T., J. H. Kim, and W. S. Park, "Matching techniques for miniaturized UHF RFID loop antennas," IEEE Antennas and Wireless Propagation Letters, Vol. 9, 266-270, 2009.
9. Wu, J., J. X. Li, X. S. Cui, and L. H. Mao, "Circular loop antenna for UHF RFID tags with inductively coupled structure," 2011 International Conference on Control, Automation and Systems Engineering (CASE), 1-4, Jul. 2011. doi:10.1109/ICCASE.2011.5997543
10. Liu, Q., Y. F. Yu, and Q. S. Huang, "Capacitively-loaded inductively-coupled fed loop antenna with an omnidirectional radiation pattern for UHF RFID tags," PIERS Proceedings, 195-197, Aug. 2013.
18. Feresidis, A. P., S. Wang, and J. C. Vardaxoglou, "Artificial magnetic conductor surfaces and their application to low-profile high-gain planar antennas," IEEE Transactions on Antennas and Propagation, Vol. 53, No. 1, 209-215, Jan. 2005. doi:10.1109/TAP.2004.840528
19. Sohn, J. R., K. Y. Kim, and H. S. Tae, "Comparative study on various artificial magnetic conductors for low-profile antenna," Progress In Electromagnetics Research, Vol. 61, 27-37, 2006. doi:10.2528/PIER06011701