Very Low Profile High Gain Helix Antenna with Fabry-Perot Cavity for UHF RFID

International audienceDecreasing the size of the UHF Radio Frequency Identification (RFID) reader antenna without reducing the tag reading performance is a challenging problem. A low profile helix antenna (0.3 lambda) with high gain for RFID reader is presented in this paper. The size reduction and high gain are obtained by feeding a cylindrical cavity closed by a frequency selective surface as Fabry-Perot structures. The cavity structure has been simulated and optimized with HFSS software. The structure has a total size of 692x692x155mm(3) and presents good performance, such as an high gain of 14.8dBic over a large bandwidth with a good axial ratio