Crossed Dipole Antenna for RFID applications

With the rapid development of the Internet of Things (IoT), the radio frequency identification (RFID) system becomes increasingly important. Nevertheless, RFID presents a series of technological challenges that have been addressed by different research groups in the last decade. One of these challenges is to increase the data storage capacity of readers and tags. This letter introduces a crossed dipole antenna for 2.45 GHz ISM band RFID readers. The crossed dipoles are composed of four trapezoidal patch arms, are fed by a 50Ω coaxial probe and are placed above a square reflector to obtain omnidirectional radiation. The achieved results show that with the advantage of centered feed, the CDA proves a symmetric radiation pattern across the entire operating bandwidth with high return loss, good impedance matching and efficiency better than 95%. The proposed CDA is low profile, low cost, and present good performances for use on microwave RFID readers.