DUAL-BAND CIRCULARLY POLARIZED ANTENNA USING COMBINED C-SHAPED AND L-SHAPED SLOTS EXCITED BY A MICROSTRIP LINE

摘要

An L-shaped slot loaded inside a C-shaped slot is used to realize a dual-band antenna fed by a microstrip line. Two circularly polarized waves are generated at the 1.57 and the 2.45 GHz band. The width in the C-slot is uniform, whereas the width in the L-slot is nonuniform. In the L-slot, the width in the vertical part is made wider than that in the horizontal part. We found that the width in the vertical part of the L-slot is an efficient tuning parameter. The antenna can achieve about 6% axial ratio bandwidth at both bands.