Design of small RFID reader antenna

Several designs for RFID reader antenna are proposed. All designs are based on planar dipole antenna without ground plane and aimed at obtaining either small dimension or mechanical stability. Also the idea is to obtain a design which can be simply modified to serve as a transponder antenna. For that reason special care is devoted to impedance matching which is achieved by modifying the feed segment of the antenna. The presented designs were first simulated and optimized to obtain the desired impedance, and then prototypes were realized. Simulated and measured results were then compared showing good agreement.