Wideband and High Gain Circularly Polarized Microstrip Antenna Array using Metasurface

A metasurface based compact dual-feed 2x2 circularly 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 x 4 periodic unit cells. The sequential phase rotational approach is used to realize wideband circular polarization characteristics. The overall size of the 2x2 antenna array is 68 mmx68 mmx3.2 mm (1.25 lambda(0)x1.25 lambda(0)x0.059 lambda(0)), at an operating frequency of 5.5 GHz. Metasurface based dual-feed 2x2 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.