Multiband Circularly Polarized Microstrip Reader Antenna for RFID Applications

The ability of a thing (in the Internet of Things) to identify itself wirelessly, using Radio Frequency waves makes them Ubiquitous. The ease of Tracking, Monitoring, Identifying and Data capturing can be owed to Radio Frequency IDentification (RFID) Systems. An RFID system consists of Reader and Tag, where they use antennas for transmitting an interrogation signal and identification data respectively. Here we propose a compact microstrip patch antenna for Ultra High Frequency (UHF) and Super High Frequency (SHF). The antenna is triband and operates at 926 MHz of UHF while at 2.48 GHz and 5.8 GHz in Microwave (another name for SHF) band. Beyond RFID applications the microwave band is defined to be used for WLAN applications by IEEE 802.11b and 802.11a standards. The performance analysis of the proposed antenna design shows that it well meets the requirements of the RFID mobile reader.