Abstract
For a reader antenna of RFID mobile terminal, the circular polarized antenna composed of an unbalanced fed ultra low profile inverted L antenna and a L-shaped slot on a rectangular conducting plane is investigated. S_<11> less than -10dB and the axial ratio less than 3 dB are satisfied at the frequencies from 854.5 MHz to 1052.1 MHz. The current distribution on the antenna and the electric field distribution on the slot is studied and the mechanism of generation of circular polarization is discussed. In the numerical analysis, the electromagnetic simulator WIPL-D based on the Method of Moments is used.
