Robust optimum design of PIFA for RFID mobile dongle applications

In this paper, a dongle-type RFID PIFA (Planar Inverted F-Antenna) structure with a resonance frequency of 920 MHz is optimized taking into account the robustness against noise factors. To achieve this, a global optimum is first sought out by means of the evolution strategy and then the robust design of the optimized antenna structure is obtained by introducing the Taguchi loss function. The validity of the proposed design method is proved through the comparison of the computed and experimental results.