Wideband and High Gain Circularly Polarized Microstrip Antenna Array using Metasurface

A metasurface based compact dual-feed
$2 \times 2$
circu-larly polarized antenna array is proposed in this paper to operate in the C band. Each single element consists of a stub inserted dual-feed square-shaped patch stacked between the ground and metasurface with
$4\times 4$
periodic unit cells. The sequential phase rotational approach is used to realize wideband circular polarization characteristics. The overall size of the
$2\times 2$
antenna array is 68 mm x 68 mm x 3.2 mm
$(1.25\lambda_{0}\times 1.25\lambda_{0}\times 0.059\lambda_{0})$
, at an operating frequency of 5.5 GHz. Metasurface based dual-feed 2 × 2 antenna array structure obtains -10 dB impedance bandwidth of 4.32-7.52 GHz (58.18%),3 dB axial ratio bandwidth of 4.48-6.62 GHz (38.9%), 3 dB gain bandwidth of 4.66-6.34 GHz (30.55 %), and simulated radiation efficiency greater than 83 %. The simulated results of the proposed circularly polarized antenna array exhibits good performance in terms of -10 dB impedance bandwidth, 3 dB axial ratio bandwidth, 3 dB gain bandwidth, gain, and radiation efficiency.