Low profile UHF RFID antenna design with EBG structures

A low profile UHF RFID antenna is designed using Electromagnetic Bang Gap (EBG) structures with high permittivity materials. The effect of dielectric permittivity constant, dielectric thickness, feed location, feed types such as probe-fed and inset-fed on antenna gain, bandwidth, and return loss when matching to the feed point has been done using transmission line and cavity models which have been studied extensively with 3D electromagnetic simulator, HFSS. The optimum microstrip patch antenna design method to have an increased reading distance with low profile is presented in detail. The results have been compared with existing results and improvement has been demonstrated.