Microstrip patch antenna for RFID applications

Abstract

The microstrip patch antenna is a popular printed resonant antenna for narrow-band microwave wireless link applications such as radio frequency identification (RFID) systems that require semi-hemispherical coverage. In this paper, a 865 MHz microstrip patch antenna fed by a microstrip line designed on a substrate is considerably studied and thoroughly analyzed. The antenna has been designed using the 3D High Frequency Structure Simulator (HFSS). The initial design provides a gain of 4.2 dBi, while the final optimized design achieved a total antenna gain of 5.6 dBi and a return loss or reflection coefficient (S11) of −35dB at 865 MHz for 116 mm patch length. Modeling and optimization of the presented microstrip patch antenna has produced results that are suitable for RFID applications.