ABSTRACT
Radio frequency identification devices (RFID) have been used widely in industrial and medical applications. Specifically, RFIDs have been applied in asset tracking and security systems by several companies extensively. RFID can store and retrieve data using RFID tags/transponders remotely. One way to increase the RFID communication distance is to improve the performance of the antenna used in the system. RFIDs are commonly used with sensors to acquire and measure physical variables such as temperature, pressure, tensile strength, and so on during the operation of electronic and mechanical devices and materials. A passive RFID tag consists of two critical components: microchip and antenna. Microstrip patch antennas are widely used RFID antennas because of their various advantages such as low profile, light weight, easy fabrication, and conformability to mounting hosts in addition to size reduction and bandwidth enhancement.
