Ultra slim and small UHF RFID tag design for mounting on curved surfaces

This paper proposes a UHF flexible passive tag antenna for Radio Frequency Identification (RFID) which operates at 902–928 MHz frequency band. As main contribution, we design an electrically small and slim tag antenna by using a flexible commercial substrate. The small antenna has dimensions of 13 mm × 28 mm × 0.35 mm. The geometry of the tag antenna was optimized, using a Genetic Algorithm, to maximize its read range. The antenna performance was evaluated on flat and curve surfaces, by means of simulations of input impedance, reflection coefficient, gain and read range. Measurements of reflection coefficient were also developed. Results prove that the tag antenna can be wrapped on cylindrical surfaces with read ranges above one meter, suitable for applications related to industrial asset management, access control and identification of small objects such as hardware tools, tin cans, spray bottles and tin PET cylindrical containers.