Dual-band circularly polarized hexagonal-slot antenna

A dual-band, circularly polarized, hexagonal-shaped slot antenna is proposed and studied using microstrip feed with L-shaped stub. The antenna consists of a hexagonal-shaped slot with a microstrip feed and L-shaped stub. An impedance transformer is used to improve the impedance matching of the slot antenna. The slot and feeding structure are fabricated on a low cost FR4 substrate. The measured results of the antenna prototype are 15.7% (3.2–3.75 GHz)\15.5% (4.42–5.1 GHz) for 3-dB axial ratio bandwidths and 8.6% (3.41–3.70 GHz)\15.5% (4.47–5.20 GHz) for VSWR