Abstract
A novel compact microstrip antenna is presented for tri-band RFID applications. The antenna consisting of a monopole like bent arm with a capacitively coupled small patch, printed on the alternative side of the ground plane, which might be common for multi-layer reader circuitry. By adjusting the dimension of the bent arm as well as the embedded bent and capacitive coupling, tri-band antenna has obtained in a small profile. The prototyped antenna shows broad impedance bandwidths (10 dB <= return loss) of 17.5, 32.7, and 25.5% accordingly in UHF (902-928MHz), 2.45GHz and 5.8GHz RFID bands with stable radiation characteristics. (C) 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1629-1632, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26044