A Wideband Circularly Polarized Slotted Patch Antenna

A low profile left-hand circularly polarized (LHCP) omnidirectional antenna is presented. The proposed antenna is consisted of a metasurface-inspired periodic patch and a feeding patch. By introducing several curved slots on the feeding patch, the two orthogonal polarized components with equal magnitude and a 90° phase difference are generated to realize CP omnidirectional radiation pattern. The simulated results show that the antenna not only has a wide operating impedance bandwidth of 17.3% and a 3-dB axial ratio bandwidth of 12.2%, but also achieves a low profile of 0.06λo (λo is the wavelength at lower frequency in the free space).