Design of Circularly Polarization H-shaped Apertures-coupled Microstrip Patch Antenna Array

A kind of circularly polarized microstrip antenna is designed in S band. The Wilkinson power divider integrated with the microstrip 90 deg phase shifter is used each unit and the patch is coupled by two orthogonal H-shaped, which can enhance the isolation of the two ports and improve the circularly polarized performance. The antenna array gain is about 14 dB. The axial-ratio value within 3dB from -20 deg to 20 deg. The cross-polarization levels in zenith direction are better than -23 dB. This results indicate that the proposed antenna realizes a good circularly polarization performance.