Compact Perturbed Hexagonal Microstrip Antenna for Dual-Band Circular Polarization

A novel dual-band circularly polarized multi-layer microstrip antenna for 3.5-/5.2-/5.8-GHz applications is presented. A stacked-patch configuration is used for the compact dual-band antenna design, and good circular polarization performance is achieved by adjusting the size of truncated corners and inserted slits of the hexagonal patches. The antenna generates circular polarization radiation at 3.49 and 5.18 GHz with good return loss and broadside radiation patterns. The measured peak gains of the antenna are 3.5 and 5.1 dBi at the lower and upper bands, respectively. In addition, the antenna occupies a small radiating area of 15.6 × 16 mm 2 .