Design of RFID Reader Antenna for WLAN/WiMAX Application

In the era of the fast-growing communication world, wireless communication plays a vital role in transferring information between senders and the receivers. RFID (Radio Frequency Identification and Detection) communication is making ease to monitor, data capture, and identify different types of equipment and assets. There is a need to develop a reader antenna which uses hybrid technology and integrate with the indoor applications. In this paper, a new design of reader microstrip patch antenna is proposed using CST Microwave Studio simulation software. A low weight, circularly polarized antenna is proposed using FR4 as a substrate with dielectric constant $\varepsilon_{r}=4.2$ and loss tangent $tan\ \delta=0.025$. Characteristics of microstrip patch antenna such as VSWR, gain, S11, and radiation pattern were analyzed at resonant frequency of 5.43GHz. The result was verified by the fabrication of the antenna, resonating at 5.5 GHz and found to be used for Indoor Localization of inventory management and supply chain administration. VSWR of the antenna is 1.05 and the gain of the antenna is 2.05 dBi. The overall size occupied by the antenna is $50\times 50 \times 1.6\ \text{mm}$.