Published in Ahn, Y. J., Harackiewicz, F.J., Kim, S. J., Park, M. J., Chung, Y. S., & Lee, B. (2008). Electrically small loop antenna for UHF band RFID tag. Antennas and Propagation Society International Symposium, 2008. AP-S 2008, 1 - 4. doi: 10.1109/APS.2008.4619847 ©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 redistribution 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.


UHF band RFID tag antenna which has a similar radiation pattern of the electrically small loop antenna is presented. The structure of the proposed tag antenna is a small circular dipole array on the xy-plane, and the antenna is fed by inductively coupled loop to flow a uniform amplitude and in phased current along its circumference. Since its radiation pattern has an omnidirectional pattern in the xy-plane, the proposed tag antenna can reduce the interference among adjacent tag antennas arranged parallel to xy-plane.